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// Copyright (C) Moondance Labs Ltd.
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// This file is part of Tanssi.
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// Tanssi is free software: you can redistribute it and/or modify
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// it under the terms of the GNU General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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// Tanssi is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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// GNU General Public License for more details.
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// You should have received a copy of the GNU General Public License
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// along with Tanssi.  If not, see <http://www.gnu.org/licenses/>.
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//! Container Chain Spawner
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//!
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//! Controls the starting and stopping of container chains.
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//!
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//! For more information about when the database is deleted, check the
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//! [Keep db flowchart](https://raw.githubusercontent.com/moondance-labs/tanssi/master/docs/keep_db_flowchart.png)
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use {
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    crate::{
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        cli::ContainerChainCli,
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        monitor::{SpawnedContainer, SpawnedContainersMonitor},
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        rpc::generate_rpc_builder::GenerateRpcBuilder,
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        service::{
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            start_node_impl_container, ContainerChainClient, MinimalContainerRuntimeApi,
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            ParachainClient,
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        },
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    },
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    cumulus_primitives_core::ParaId,
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    cumulus_relay_chain_interface::RelayChainInterface,
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    dancebox_runtime::{opaque::Block as OpaqueBlock, Block},
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    dc_orchestrator_chain_interface::{OrchestratorChainInterface, PHash},
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    frame_support::{CloneNoBound, DefaultNoBound},
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    fs2::FileExt,
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    futures::FutureExt,
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    node_common::command::generate_genesis_block,
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    pallet_author_noting_runtime_api::AuthorNotingApi,
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    polkadot_primitives::CollatorPair,
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    sc_cli::{Database, SyncMode},
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    sc_network::config::MultiaddrWithPeerId,
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    sc_service::SpawnTaskHandle,
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    sc_transaction_pool::TransactionPoolHandle,
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    sp_api::ProvideRuntimeApi,
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    sp_core::H256,
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    sp_keystore::KeystorePtr,
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    sp_runtime::traits::Block as BlockT,
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    std::{
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        any::Any,
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        collections::{HashMap, HashSet},
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        marker::PhantomData,
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        path::{Path, PathBuf},
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        sync::{Arc, Mutex},
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        time::Instant,
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    },
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    tokio::{
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        sync::{mpsc, oneshot},
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        time::{sleep, Duration},
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    },
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    tokio_util::sync::CancellationToken,
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};
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/// Timeout to wait for the database to close before starting it again, used in `wait_for_paritydb_lock`.
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/// This is the max timeout, if the db is closed in 1 second then that function will only wait 1 second.
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const MAX_DB_RESTART_TIMEOUT: Duration = Duration::from_secs(60);
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/// Block diff threshold above which we decide it will be faster to delete the database and
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/// use warp sync, rather than using full sync to download a large number of blocks.
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/// This is only needed because warp sync does not support syncing from a state that is not
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/// genesis, it falls back to full sync in that case.
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/// 30_000 blocks = 50 hours at 6s/block.
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/// Assuming a syncing speed of 100 blocks per second, this will take 5 minutes to sync.
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const MAX_BLOCK_DIFF_FOR_FULL_SYNC: u32 = 30_000;
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/// Task that handles spawning a stopping container chains based on assignment.
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/// The main loop is [rx_loop](ContainerChainSpawner::rx_loop).
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pub struct ContainerChainSpawner<
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    RuntimeApi: MinimalContainerRuntimeApi,
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    TGenerateRpcBuilder: GenerateRpcBuilder<RuntimeApi>,
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> {
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    /// Start container chain params
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    pub params: ContainerChainSpawnParams<RuntimeApi, TGenerateRpcBuilder>,
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    /// State
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    pub state: Arc<Mutex<ContainerChainSpawnerState>>,
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    /// Before the first assignment, there is a db cleanup process that removes folders of container
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    /// chains that we are no longer assigned to.
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    pub db_folder_cleanup_done: bool,
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    /// Async callback that enables collation on the orchestrator chain
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    pub collate_on_tanssi:
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        Arc<dyn Fn() -> (CancellationToken, futures::channel::oneshot::Receiver<()>) + Send + Sync>,
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    /// Stores the cancellation token used to stop the orchestrator chain collator process.
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    /// When this is None, the orchestrator collator is not running.
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    pub collation_cancellation_constructs:
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        Option<(CancellationToken, futures::channel::oneshot::Receiver<()>)>,
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}
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/// Struct with all the params needed to start a container chain node given the CLI arguments,
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/// and creating the ChainSpec from on-chain data from the orchestrator chain.
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/// These params must be the same for all container chains, params that change such as the
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/// `container_chain_para_id` should be passed as separate arguments to the [try_spawn] function.
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///
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/// This struct MUST NOT contain types (outside of `Option<CollationParams>`) obtained through
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/// running an embeded orchestrator node, as this will prevent spawning a container chain in a node
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/// connected to an orchestrator node through WebSocket.
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#[derive(CloneNoBound)]
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pub struct ContainerChainSpawnParams<
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    RuntimeApi: MinimalContainerRuntimeApi,
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    TGenerateRpcBuilder: GenerateRpcBuilder<RuntimeApi>,
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> {
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    pub orchestrator_chain_interface: Arc<dyn OrchestratorChainInterface>,
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    pub container_chain_cli: ContainerChainCli,
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    pub tokio_handle: tokio::runtime::Handle,
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    pub chain_type: sc_chain_spec::ChainType,
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    pub relay_chain: String,
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    pub relay_chain_interface: Arc<dyn RelayChainInterface>,
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    pub sync_keystore: KeystorePtr,
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    pub orchestrator_para_id: ParaId,
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    pub spawn_handle: SpawnTaskHandle,
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    pub collation_params: Option<CollationParams>,
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    pub data_preserver: bool,
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    pub generate_rpc_builder: TGenerateRpcBuilder,
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    pub phantom: PhantomData<RuntimeApi>,
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}
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/// Params specific to collation. This struct can contain types obtained through running an
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/// embeded orchestrator node.
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#[derive(Clone)]
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pub struct CollationParams {
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    pub collator_key: CollatorPair,
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    pub orchestrator_tx_pool: Option<Arc<TransactionPoolHandle<OpaqueBlock, ParachainClient>>>,
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    pub orchestrator_client: Option<Arc<ParachainClient>>,
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    pub orchestrator_para_id: ParaId,
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    /// If this is `false`, then `orchestrator_tx_pool` and `orchestrator_client` must be `Some`.
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    pub solochain: bool,
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}
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/// Mutable state for container chain spawner. Keeps track of running chains.
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#[derive(DefaultNoBound)]
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pub struct ContainerChainSpawnerState {
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    spawned_container_chains: HashMap<ParaId, ContainerChainState>,
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    assigned_para_id: Option<ParaId>,
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    next_assigned_para_id: Option<ParaId>,
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    failed_para_ids: HashSet<ParaId>,
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    // For debugging and detecting errors
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    pub spawned_containers_monitor: SpawnedContainersMonitor,
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}
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pub struct ContainerChainState {
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    /// Handle that can be used to stop the container chain
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    stop_handle: StopContainerChain,
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    /// Database path
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    db_path: PathBuf,
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}
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/// Stops a container chain when signal is sent. The bool means `keep_db`, whether to keep the
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/// container chain database (true) or remove it (false).
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pub struct StopContainerChain {
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    signal: oneshot::Sender<bool>,
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    id: usize,
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}
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/// Messages used to control the `ContainerChainSpawner`. This is needed because one of the fields
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/// of `ContainerChainSpawner` is not `Sync`, so we cannot simply pass an
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/// `Arc<ContainerChainSpawner>` to other threads.
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#[derive(Debug)]
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pub enum CcSpawnMsg {
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    /// Update container chain assignment
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    UpdateAssignment {
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        current: Option<ParaId>,
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        next: Option<ParaId>,
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    },
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}
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// Separate function to allow using `?` to return a result, and also to avoid using `self` in an
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// async function. Mutable state should be written by locking `state`.
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// TODO: `state` should be an async mutex
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async fn try_spawn<
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    RuntimeApi: MinimalContainerRuntimeApi,
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    TGenerateRpcBuilder: GenerateRpcBuilder<RuntimeApi>,
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>(
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    try_spawn_params: ContainerChainSpawnParams<RuntimeApi, TGenerateRpcBuilder>,
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    state: Arc<Mutex<ContainerChainSpawnerState>>,
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    container_chain_para_id: ParaId,
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    start_collation: bool,
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) -> sc_service::error::Result<()> {
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    let ContainerChainSpawnParams {
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        orchestrator_chain_interface,
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        mut container_chain_cli,
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        tokio_handle,
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        chain_type,
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        relay_chain,
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        relay_chain_interface,
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        sync_keystore,
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        spawn_handle,
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        mut collation_params,
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        data_preserver,
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        generate_rpc_builder,
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        ..
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    } = try_spawn_params;
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    // Preload genesis data from orchestrator chain storage.
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    // TODO: the orchestrator chain node may not be fully synced yet,
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    // in that case we will be reading an old state.
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    let orchestrator_block_hash = orchestrator_chain_interface
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        .finalized_block_hash()
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        .await
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        .map_err(|e| format!("Failed to get latest block hash: {e}"))?;
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    log::info!(
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        "Detected assignment for container chain {}",
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        container_chain_para_id
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    );
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    let genesis_data = orchestrator_chain_interface
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        .genesis_data(orchestrator_block_hash, container_chain_para_id)
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        .await
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        .map_err(|e| format!("Failed to call genesis_data runtime api: {}", e))?
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        .ok_or_else(|| {
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            format!(
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                "No genesis data registered for container chain id {}",
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                container_chain_para_id
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            )
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        })?;
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    let boot_nodes_raw = orchestrator_chain_interface
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        .boot_nodes(orchestrator_block_hash, container_chain_para_id)
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        .await
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        .map_err(|e| format!("Failed to call boot_nodes runtime api: {}", e))?;
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    if boot_nodes_raw.is_empty() {
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        log::warn!(
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            "No boot nodes registered on-chain for container chain {}",
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            container_chain_para_id
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        );
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    }
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    let boot_nodes = parse_boot_nodes_ignore_invalid(boot_nodes_raw, container_chain_para_id);
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    if boot_nodes.is_empty() {
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        log::warn!(
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            "No valid boot nodes for container chain {}",
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            container_chain_para_id
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        );
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    }
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    container_chain_cli
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        .preload_chain_spec_from_genesis_data(
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            container_chain_para_id.into(),
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            genesis_data,
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            chain_type.clone(),
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            relay_chain.clone(),
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            boot_nodes,
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        )
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        .map_err(|e| {
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            format!(
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                "failed to create container chain chain spec from on chain genesis data: {}",
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                e
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            )
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        })?;
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    log::info!(
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        "Loaded chain spec for container chain {}",
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        container_chain_para_id
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    );
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    if !data_preserver && !start_collation {
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        log::info!("This is a syncing container chain, using random ports");
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        collation_params = None;
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        // Use random ports to avoid conflicts with the other running container chain
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        let random_ports = [23456, 23457, 23458];
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        container_chain_cli
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            .base
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            .base
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            .prometheus_params
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            .prometheus_port = Some(random_ports[0]);
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        container_chain_cli.base.base.network_params.port = Some(random_ports[1]);
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        container_chain_cli.base.base.rpc_params.rpc_port = Some(random_ports[2]);
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    }
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    let validator = collation_params.is_some();
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    // Update CLI params
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    container_chain_cli.base.para_id = Some(container_chain_para_id.into());
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    container_chain_cli
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        .base
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        .base
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        .import_params
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        .database_params
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        .database = Some(Database::ParityDb);
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    let keep_db = container_chain_cli.base.keep_db;
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    // Get a closure that checks if db_path exists.Need this to know when to use full sync instead of warp sync.
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    let check_db_exists = {
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        // Get db_path from config
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        let mut container_chain_cli_config = sc_cli::SubstrateCli::create_configuration(
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            &container_chain_cli,
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            &container_chain_cli,
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            tokio_handle.clone(),
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        )
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        .map_err(|err| format!("Container chain argument error: {}", err))?;
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        // Change database path to make it depend on container chain para id
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        // So instead of the usual "db/full" we have "db/full-container-2000"
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        let mut db_path = container_chain_cli_config
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            .database
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            .path()
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            .ok_or_else(|| "Failed to get database path".to_string())?
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            .to_owned();
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        db_path.set_file_name(format!("full-container-{}", container_chain_para_id));
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        container_chain_cli_config.database.set_path(&db_path);
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        // Return a closure because we may need to check if the db exists multiple times
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        move || db_path.exists()
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    };
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    // Start container chain node. After starting, check if the database is good or needs to
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    // be removed. If the db needs to be removed, this function will handle the node restart, and
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    // return the components of a running container chain node.
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    // This should be a separate function, but it has so many arguments that I prefer to have it as a closure for now
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    let start_node_impl_container_with_restart = || async move {
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        // Loop will run at most 2 times: 1 time if the db is good and 2 times if the db needs to be removed
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        for _ in 0..2 {
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            let db_existed_before = check_db_exists();
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            container_chain_cli.base.base.network_params.sync = SyncMode::Warp;
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            log::info!(
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                "Container chain sync mode: {:?}",
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                container_chain_cli.base.base.network_params.sync
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            );
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            let mut container_chain_cli_config = sc_cli::SubstrateCli::create_configuration(
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                &container_chain_cli,
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                &container_chain_cli,
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                tokio_handle.clone(),
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            )
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            .map_err(|err| format!("Container chain argument error: {}", err))?;
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            // Change database path to make it depend on container chain para id
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            // So instead of the usual "db/full" we have "db/full-container-2000"
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            let mut db_path = container_chain_cli_config
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                .database
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                .path()
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                .ok_or_else(|| "Failed to get database path".to_string())?
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                .to_owned();
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            db_path.set_file_name(format!("full-container-{}", container_chain_para_id));
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            container_chain_cli_config.database.set_path(&db_path);
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            let (container_chain_task_manager, container_chain_client, container_chain_db) =
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                start_node_impl_container(
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                    container_chain_cli_config,
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                    relay_chain_interface.clone(),
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                    orchestrator_chain_interface.clone(),
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                    sync_keystore.clone(),
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                    container_chain_para_id,
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                    collation_params.clone(),
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                    generate_rpc_builder.clone(),
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                    &container_chain_cli,
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                    data_preserver,
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                )
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                .await?;
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            // Keep all node parts in one variable to make them easier to drop
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            let node_parts = (
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                container_chain_task_manager,
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                container_chain_client,
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                container_chain_db,
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                db_path,
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            );
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            if db_existed_before {
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                // If the database already existed before, check if it can be used or it needs to be removed.
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                // To remove the database, we restart the node, wait for the db to close to avoid a
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                // "shutdown error" log, and then remove it.
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                if let Some(db_removal_reason) = db_needs_removal(
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                    &node_parts.1,
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                    &orchestrator_chain_interface,
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                    orchestrator_block_hash,
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                    container_chain_para_id,
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                    &container_chain_cli,
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                    container_chain_cli.base.keep_db,
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                )
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                .await?
392
                {
393
                    let db_path = node_parts.3.clone();
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                    // Important, drop `node_parts` before trying to `wait_for_paritydb_lock`
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                    drop(node_parts);
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                    // Wait here to for the database created in the previous loop iteration to close.
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                    // Dropping is not enough because there is some background process that keeps the database open,
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                    // so we check the paritydb lock file directly.
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                    log::info!(
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                        "Restarting container chain {} after db deletion. Reason: {:?}",
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                        container_chain_para_id,
402
                        db_removal_reason,
403
                    );
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                    wait_for_paritydb_lock(&db_path, MAX_DB_RESTART_TIMEOUT)
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                        .await
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                        .map_err(|e| {
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                            log::warn!(
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                                "Error waiting for chain {} to release db lock: {:?}",
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                                container_chain_para_id,
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                                e
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                            );
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413
                            e
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                        })?;
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                    delete_container_chain_db(&db_path);
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                    // Recursion, will only happen once because `db_existed_before` will be false after
418
                    // removing the db. Apparently closures cannot be recursive so fake recursion by
419
                    // using a loop + continue
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                    continue;
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                }
422
            }
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            // If using full sync, print a warning if the local db is at block 0 and the chain has thousands of blocks
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            if container_chain_cli.base.base.network_params.sync == SyncMode::Full {
426
                let last_container_block_temp = node_parts.1.chain_info().best_number;
427
                let cc_block_num = get_latest_container_block_number_from_orchestrator(
428
                    &orchestrator_chain_interface,
429
                    orchestrator_block_hash,
430
                    container_chain_para_id,
431
                )
432
                .await
433
                .unwrap_or(0);
434
                if last_container_block_temp == 0 && cc_block_num > MAX_BLOCK_DIFF_FOR_FULL_SYNC {
435
                    let db_folder = format!("full-container-{}", container_chain_para_id);
436
                    log::error!("\
437
                        Existing database for container chain {} is at block 0, assuming that warp sync failed.\n\
438
                        The node will now use full sync, which has to download {} blocks.\n\
439
                        If running as collator, it may not finish syncing on time and miss block rewards.\n\
440
                        To force using warp sync, stop tanssi-node and manually remove the db folder: {:?}\n\
441
                        ", container_chain_para_id, cc_block_num, db_folder)
442
                }
443
            }
444

            
445
            return sc_service::error::Result::Ok(node_parts);
446
        }
447

            
448
        unreachable!("Above loop can run at most 2 times, and in the second iteration it is guaranteed to return")
449
    };
450

            
451
    let (mut container_chain_task_manager, container_chain_client, container_chain_db, db_path) =
452
        start_node_impl_container_with_restart().await?;
453

            
454
    // Signal that allows to gracefully stop a container chain
455
    let (signal, on_exit) = oneshot::channel::<bool>();
456

            
457
    let monitor_id;
458
    {
459
        let mut state = state.lock().expect("poison error");
460
        let container_chain_client = container_chain_client as Arc<dyn Any + Sync + Send>;
461

            
462
        monitor_id = state.spawned_containers_monitor.push(SpawnedContainer {
463
            id: 0,
464
            para_id: container_chain_para_id,
465
            start_time: Instant::now(),
466
            stop_signal_time: None,
467
            stop_task_manager_time: None,
468
            stop_refcount_time: Default::default(),
469
            backend: Arc::downgrade(&container_chain_db),
470
            client: Arc::downgrade(&container_chain_client),
471
        });
472

            
473
        if state
474
            .spawned_container_chains
475
            .contains_key(&container_chain_para_id)
476
        {
477
            return Err(format!("Tried to spawn a container chain when another container chain with the same para id was already running: {:?}", container_chain_para_id).into());
478
        }
479
        state.spawned_container_chains.insert(
480
            container_chain_para_id,
481
            ContainerChainState {
482
                stop_handle: StopContainerChain {
483
                    signal,
484
                    id: monitor_id,
485
                },
486
                db_path: db_path.clone(),
487
            },
488
        );
489
    }
490

            
491
    // Add the container chain task manager as a child task to the parent task manager.
492
    // We want to stop the node if this task manager stops, but we also want to allow a
493
    // graceful shutdown using the `on_exit` future.
494
    let name = "container-chain-task-manager";
495
    spawn_handle.spawn(name, None, async move {
496
        let mut container_chain_task_manager_future =
497
            container_chain_task_manager.future().fuse();
498
        let mut on_exit_future = on_exit.fuse();
499

            
500
        futures::select! {
501
            res1 = container_chain_task_manager_future => {
502
                // An essential task failed or the task manager was stopped unexpectedly
503
                // using `.terminate()`. This should stop the container chain but not the node.
504
                if res1.is_err() {
505
                    log::error!("Essential task failed in container chain {} task manager. Shutting down container chain service", container_chain_para_id);
506
                } else {
507
                    log::error!("Unexpected shutdown in container chain {} task manager. Shutting down container chain service", container_chain_para_id);
508
                }
509
                // Mark this container chain as "failed to stop" to avoid warning in `self.stop()`
510
                let mut state = state.lock().expect("poison error");
511
                state.failed_para_ids.insert(container_chain_para_id);
512
                // Never delete db in this case because it is not a graceful shutdown
513
            }
514
            stop_unassigned = on_exit_future => {
515
                // Graceful shutdown.
516
                // `stop_unassigned` will be `Ok(keep_db)` if `.stop()` has been called, which means that the
517
                // container chain has been unassigned, and will be `Err` if the handle has been dropped,
518
                // which means that the node is stopping.
519
                // Delete existing database if running as collator
520
                if validator && stop_unassigned == Ok(false) && !keep_db {
521
                    // If this breaks after a code change, make sure that all the variables that
522
                    // may keep the chain alive are dropped before the call to `wait_for_paritydb_lock`.
523
                    drop(container_chain_task_manager_future);
524
                    drop(container_chain_task_manager);
525
                    let db_closed = wait_for_paritydb_lock(&db_path, MAX_DB_RESTART_TIMEOUT)
526
                        .await
527
                        .map_err(|e| {
528
                            log::warn!(
529
                                "Error waiting for chain {} to release db lock: {:?}",
530
                                container_chain_para_id,
531
                                e
532
                            );
533
                        }).is_ok();
534
                    // If db has not closed in 60 seconds we do not delete it.
535
                    if db_closed {
536
                        delete_container_chain_db(&db_path);
537
                    }
538
                }
539
            }
540
        }
541

            
542
        let mut state = state.lock().expect("poison error");
543
        state
544
            .spawned_containers_monitor
545
            .set_stop_task_manager_time(monitor_id, Instant::now());
546
    });
547

            
548
    Ok(())
549
}
550

            
551
/// Interface for spawning and stopping container chain embeded nodes.
552
pub trait Spawner {
553
    /// Access to the Orchestrator Chain Interface
554
    fn orchestrator_chain_interface(&self) -> Arc<dyn OrchestratorChainInterface>;
555

            
556
    /// Try to start a new container chain. In case of an error, this does not stop the node, and
557
    /// the container chain will be attempted to spawn again when the collator is reassigned to it.
558
    ///
559
    /// It is possible that we try to spawn-stop-spawn the same chain, and the second spawn fails
560
    /// because the chain has not stopped yet, because `stop` does not wait for the chain to stop,
561
    /// so before calling `spawn` make sure to call `wait_for_paritydb_lock` before, like we do in
562
    /// `handle_update_assignment`.
563
    fn spawn(
564
        &self,
565
        container_chain_para_id: ParaId,
566
        start_collation: bool,
567
    ) -> impl std::future::Future<Output = ()> + Send;
568

            
569
    /// Stop a container chain. Prints a warning if the container chain was not running.
570
    /// Returns the database path for the container chain, can be used with `wait_for_paritydb_lock`
571
    /// to ensure that the container chain has fully stopped. The database path can be `None` if the
572
    /// chain was not running.
573
    fn stop(&self, container_chain_para_id: ParaId, keep_db: bool) -> Option<PathBuf>;
574
}
575

            
576
impl<
577
        RuntimeApi: MinimalContainerRuntimeApi,
578
        TGenerateRpcBuilder: GenerateRpcBuilder<RuntimeApi>,
579
    > Spawner for ContainerChainSpawner<RuntimeApi, TGenerateRpcBuilder>
580
{
581
    /// Access to the Orchestrator Chain Interface
582
    fn orchestrator_chain_interface(&self) -> Arc<dyn OrchestratorChainInterface> {
583
        self.params.orchestrator_chain_interface.clone()
584
    }
585

            
586
    /// Try to start a new container chain. In case of an error, this does not stop the node, and
587
    /// the container chain will be attempted to spawn again when the collator is reassigned to it.
588
    ///
589
    /// It is possible that we try to spawn-stop-spawn the same chain, and the second spawn fails
590
    /// because the chain has not stopped yet, because `stop` does not wait for the chain to stop,
591
    /// so before calling `spawn` make sure to call `wait_for_paritydb_lock` before, like we do in
592
    /// `handle_update_assignment`.
593
    async fn spawn(&self, container_chain_para_id: ParaId, start_collation: bool) {
594
        let try_spawn_params = self.params.clone();
595
        let state = self.state.clone();
596
        let state2 = state.clone();
597

            
598
        match try_spawn(
599
            try_spawn_params,
600
            state,
601
            container_chain_para_id,
602
            start_collation,
603
        )
604
        .await
605
        {
606
            Ok(()) => {}
607
            Err(e) => {
608
                log::error!(
609
                    "Failed to start container chain {}: {}",
610
                    container_chain_para_id,
611
                    e
612
                );
613
                // Mark this container chain as "failed to start"
614
                let mut state = state2.lock().expect("poison error");
615
                state.failed_para_ids.insert(container_chain_para_id);
616
            }
617
        }
618
    }
619

            
620
    /// Stop a container chain. Prints a warning if the container chain was not running.
621
    /// Returns the database path for the container chain, can be used with `wait_for_paritydb_lock`
622
    /// to ensure that the container chain has fully stopped. The database path can be `None` if the
623
    /// chain was not running.
624
    fn stop(&self, container_chain_para_id: ParaId, keep_db: bool) -> Option<PathBuf> {
625
        let mut state = self.state.lock().expect("poison error");
626
        let stop_handle = state
627
            .spawned_container_chains
628
            .remove(&container_chain_para_id);
629

            
630
        match stop_handle {
631
            Some(stop_handle) => {
632
                log::info!("Stopping container chain {}", container_chain_para_id);
633

            
634
                let id = stop_handle.stop_handle.id;
635
                state
636
                    .spawned_containers_monitor
637
                    .set_stop_signal_time(id, Instant::now());
638

            
639
                // Send signal to perform graceful shutdown, which will delete the db if needed
640
                let _ = stop_handle.stop_handle.signal.send(keep_db);
641

            
642
                Some(stop_handle.db_path)
643
            }
644
            None => {
645
                // Do not print the warning message if this is a container chain that has failed to
646
                // start, because in that case it will not be running
647
                if !state.failed_para_ids.remove(&container_chain_para_id) {
648
                    log::warn!(
649
                        "Tried to stop a container chain that is not running: {}",
650
                        container_chain_para_id
651
                    );
652
                }
653

            
654
                None
655
            }
656
        }
657
    }
658
}
659

            
660
impl<
661
        RuntimeApi: MinimalContainerRuntimeApi,
662
        TGenerateRpcBuilder: GenerateRpcBuilder<RuntimeApi>,
663
    > ContainerChainSpawner<RuntimeApi, TGenerateRpcBuilder>
664
{
665
    /// Receive and process `CcSpawnMsg`s indefinitely
666
    pub async fn rx_loop(
667
        mut self,
668
        mut rx: mpsc::UnboundedReceiver<CcSpawnMsg>,
669
        validator: bool,
670
        solochain: bool,
671
    ) {
672
        // The node always starts as an orchestrator chain collator.
673
        // This is because the assignment is detected after importing a new block, so if all
674
        // collators stop at the same time, when they start again nobody will produce the new block.
675
        // So all nodes start as orchestrator chain collators, until the first block is imported,
676
        // then the real assignment is used.
677
        // Except in solochain mode, then the initial assignment is None.
678
        if validator && !solochain {
679
            self.handle_update_assignment(Some(self.params.orchestrator_para_id), None)
680
                .await;
681
        }
682

            
683
        while let Some(msg) = rx.recv().await {
684
            match msg {
685
                CcSpawnMsg::UpdateAssignment { current, next } => {
686
                    self.handle_update_assignment(current, next).await;
687
                }
688
            }
689
        }
690

            
691
        // The while loop can end if all the senders get dropped, but since this is an
692
        // essential task we don't want it to stop. So await a future that never completes.
693
        // This should only happen when starting a full node.
694
        if !validator {
695
            let () = std::future::pending().await;
696
        }
697
    }
698

            
699
    /// Handle `CcSpawnMsg::UpdateAssignment`
700
    async fn handle_update_assignment(&mut self, current: Option<ParaId>, next: Option<ParaId>) {
701
        if !self.db_folder_cleanup_done {
702
            self.db_folder_cleanup_done = true;
703

            
704
            // Disabled when running with --keep-db
705
            let keep_db = self.params.container_chain_cli.base.keep_db;
706
            if !keep_db {
707
                let mut chains_to_keep = HashSet::new();
708
                chains_to_keep.extend(current);
709
                chains_to_keep.extend(next);
710
                self.db_folder_cleanup(&chains_to_keep);
711
            }
712
        }
713

            
714
        let HandleUpdateAssignmentResult {
715
            chains_to_stop,
716
            chains_to_start,
717
            need_to_restart: _,
718
        } = handle_update_assignment_state_change(
719
            &mut self.state.lock().expect("poison error"),
720
            self.params.orchestrator_para_id,
721
            current,
722
            next,
723
        );
724

            
725
        if current != Some(self.params.orchestrator_para_id) {
726
            // If not assigned to orchestrator chain anymore, we need to stop the collator process
727
            let maybe_exit_notification_receiver = self
728
                .collation_cancellation_constructs
729
                .take()
730
                .map(|(cancellation_token, exit_notification_receiver)| {
731
                    cancellation_token.cancel();
732
                    exit_notification_receiver
733
                });
734

            
735
            if let Some(exit_notification_receiver) = maybe_exit_notification_receiver {
736
                let _ = exit_notification_receiver.await;
737
            }
738
        } else if self.collation_cancellation_constructs.is_none() {
739
            // If assigned to orchestrator chain but the collator process is not running, start it
740
            self.collation_cancellation_constructs = Some((self.collate_on_tanssi)());
741
        }
742

            
743
        // Stop all container chains that are no longer needed
744
        let mut db_paths_restart = vec![];
745
        for para_id in chains_to_stop {
746
            // Keep db if we are currently assigned to this chain
747
            let keep_db = Some(para_id) == current;
748
            let maybe_db_path = self.stop(para_id, keep_db);
749
            // If we are restarting this chain, save its db_path to check when it actually stopped
750
            if let Some(db_path) = maybe_db_path {
751
                if chains_to_start.contains(&para_id) {
752
                    db_paths_restart.push((para_id, db_path));
753
                }
754
            }
755
        }
756

            
757
        if !db_paths_restart.is_empty() {
758
            // Ensure the chains we stopped actually stopped by checking if their database is unlocked.
759
            // Using `join_all` because in one edge case we may be restarting 2 chains,
760
            // but almost always this will be only one future.
761
            let futs = db_paths_restart
762
                .into_iter()
763
                .map(|(para_id, db_path)| async move {
764
                    wait_for_paritydb_lock(&db_path, MAX_DB_RESTART_TIMEOUT)
765
                        .await
766
                        .map_err(|e| {
767
                            log::warn!(
768
                                "Error waiting for chain {} to release db lock: {:?}",
769
                                para_id,
770
                                e
771
                            );
772
                        })
773
                });
774
            futures::future::join_all(futs).await;
775
        }
776

            
777
        // Start all new container chains (usually 1)
778
        for para_id in chains_to_start {
779
            // Edge case: when starting the node it may be assigned to a container chain, so we need to
780
            // start a container chain already collating.
781
            // TODO: another edge case: if current == None, and running_chains == 0,
782
            // and chains_to_start == 1, we can start this chain as collating, and we won't need
783
            // to restart it on the next session. We need to add some extra state somewhere to
784
            // implement this properly.
785
            let start_collation = Some(para_id) == current;
786
            self.spawn(para_id, start_collation).await;
787
        }
788
    }
789

            
790
    fn db_folder_cleanup(&self, chains_to_keep: &HashSet<ParaId>) {
791
        // "containers" folder
792
        let mut base_path = self
793
            .params
794
            .container_chain_cli
795
            .base
796
            .base
797
            .shared_params
798
            .base_path
799
            .as_ref()
800
            .expect("base_path is always set")
801
            .to_owned();
802

            
803
        // "containers/chains"
804
        base_path.push("chains");
805

            
806
        // Inside chains folder we have container folders such as
807
        // containers/chains/simple_container_2000/
808
        // containers/chains/frontier_container_2001/
809
        // But this is not the para id, it's the chain id which we have set to include the para id, but that's not mandatory.
810
        // To get the para id we need to look for the paritydb folder:
811
        // containers/chains/frontier_container_2001/paritydb/full-container-2001/
812
        let mut chain_folders = sort_container_folders_by_para_id(&base_path);
813

            
814
        // Keep chains that we are assigned to
815
        for para_id in chains_to_keep {
816
            chain_folders.remove(&Some(*para_id));
817
        }
818

            
819
        // Print nice log message when removing folders
820
        if !chain_folders.is_empty() {
821
            let chain_folders_fmt = chain_folders
822
                .iter()
823
                .flat_map(|(para_id, vec_paths)| {
824
                    let para_id_fmt = if let Some(para_id) = para_id {
825
                        para_id.to_string()
826
                    } else {
827
                        "None".to_string()
828
                    };
829
                    vec_paths
830
                        .iter()
831
                        .map(move |path| format!("\n{}: {}", para_id_fmt, path.display()))
832
                })
833
                .collect::<String>();
834
            log::info!(
835
                "db_folder_cleanup: removing container folders: (para_id, path):{}",
836
                chain_folders_fmt
837
            );
838
        }
839

            
840
        // Remove, ignoring errors
841
        for (_para_id, folders) in chain_folders {
842
            for folder in folders {
843
                let _ = std::fs::remove_dir_all(&folder);
844
            }
845
        }
846
    }
847
}
848

            
849
struct HandleUpdateAssignmentResult {
850
    chains_to_stop: Vec<ParaId>,
851
    chains_to_start: Vec<ParaId>,
852
    #[allow(dead_code)] // no longer used except in tests
853
    need_to_restart: bool,
854
}
855

            
856
// This is a separate function to allow testing
857
35
fn handle_update_assignment_state_change(
858
35
    state: &mut ContainerChainSpawnerState,
859
35
    orchestrator_para_id: ParaId,
860
35
    current: Option<ParaId>,
861
35
    next: Option<ParaId>,
862
35
) -> HandleUpdateAssignmentResult {
863
35
    if (state.assigned_para_id, state.next_assigned_para_id) == (current, next) {
864
        // If nothing changed there is nothing to update
865
        return HandleUpdateAssignmentResult {
866
            chains_to_stop: Default::default(),
867
            chains_to_start: Default::default(),
868
            need_to_restart: false,
869
        };
870
35
    }
871
35

            
872
35
    // Create a set with the container chains that were running before, and the container
873
35
    // chains that should be running after the updated assignment. This is used to calculate
874
35
    // the difference, and stop and start the required container chains.
875
35
    let mut running_chains_before = HashSet::new();
876
35
    let mut running_chains_after = HashSet::new();
877
35

            
878
35
    running_chains_before.extend(state.assigned_para_id);
879
35
    running_chains_before.extend(state.next_assigned_para_id);
880
35
    // Ignore orchestrator_para_id because it is handled in a special way, as it does not need to
881
35
    // start one session before in order to sync.
882
35
    running_chains_before.remove(&orchestrator_para_id);
883
35

            
884
35
    running_chains_after.extend(current);
885
35
    running_chains_after.extend(next);
886
35
    running_chains_after.remove(&orchestrator_para_id);
887
35
    let mut need_to_restart_current = false;
888
35
    let mut need_to_restart_next = false;
889
35

            
890
35
    if state.assigned_para_id != current {
891
24
        if let Some(para_id) = current {
892
            // If the assigned container chain has changed, we may need to
893
            // restart it in collation mode, unless it is the orchestrator chain.
894
16
            if para_id != orchestrator_para_id {
895
13
                need_to_restart_current = true;
896
13
            }
897
8
        }
898

            
899
24
        if let Some(para_id) = state.assigned_para_id {
900
18
            if para_id != orchestrator_para_id && Some(para_id) == next {
901
2
                need_to_restart_next = true;
902
16
            }
903
6
        }
904
11
    }
905

            
906
35
    state.assigned_para_id = current;
907
35
    state.next_assigned_para_id = next;
908
35

            
909
35
    let mut chains_to_stop: Vec<_> = running_chains_before
910
35
        .difference(&running_chains_after)
911
35
        .copied()
912
35
        .collect();
913
35
    let mut chains_to_start: Vec<_> = running_chains_after
914
35
        .difference(&running_chains_before)
915
35
        .copied()
916
35
        .collect();
917
35

            
918
35
    if need_to_restart_current {
919
        // Force restart of new assigned container chain: if it was running before it was in "syncing mode",
920
        // which doesn't use the correct ports, so start it in "collation mode".
921
13
        let id = current.unwrap();
922
13
        if running_chains_before.contains(&id) && !chains_to_stop.contains(&id) {
923
6
            chains_to_stop.push(id);
924
7
        }
925
13
        if !chains_to_start.contains(&id) {
926
6
            chains_to_start.push(id);
927
7
        }
928
22
    }
929

            
930
35
    if need_to_restart_next {
931
        // Handle edge case of going from (2000, 2001) to (2001, 2000). In that case we must restart both chains,
932
        // because previously 2000 was collating and now 2000 will only be syncing.
933
2
        let id = next.unwrap();
934
2
        if running_chains_before.contains(&id) && !chains_to_stop.contains(&id) {
935
2
            chains_to_stop.push(id);
936
2
        }
937
2
        if !chains_to_start.contains(&id) {
938
2
            chains_to_start.push(id);
939
2
        }
940
33
    }
941

            
942
    HandleUpdateAssignmentResult {
943
35
        chains_to_stop,
944
35
        chains_to_start,
945
35
        need_to_restart: need_to_restart_current || need_to_restart_next,
946
    }
947
35
}
948

            
949
/// Select [SyncMode] to use for a container chain.
950
/// We want to use warp sync unless the db still exists, or the container chain is
951
/// still at genesis block (because of a warp sync bug in that case).
952
///
953
/// Remember that warp sync doesn't work if a partially synced database already exists, it falls
954
/// back to full sync instead. The only exception is if the previous instance of the database was
955
/// interrupted before it finished downloading the state, in that case the node will use warp sync.
956
/// If it was interrupted during the block history download, the node will use full sync but also
957
/// finish the block history download in the background, even if sync mode is set to full sync.
958
pub fn select_sync_mode_using_client(
959
    db_exists: bool,
960
    orchestrator_client: &Arc<ParachainClient>,
961
    container_chain_para_id: ParaId,
962
) -> sc_service::error::Result<SyncMode> {
963
    if db_exists {
964
        // If the user wants to use warp sync, they should have already removed the database
965
        return Ok(SyncMode::Full);
966
    }
967

            
968
    // The following check is only needed because of this bug:
969
    // https://github.com/paritytech/polkadot-sdk/issues/1930
970

            
971
    let orchestrator_runtime_api = orchestrator_client.runtime_api();
972
    let orchestrator_chain_info = orchestrator_client.chain_info();
973

            
974
    // If the container chain is still at genesis block, use full sync because warp sync is broken
975
    let full_sync_needed = orchestrator_runtime_api
976
        .latest_author(orchestrator_chain_info.best_hash, container_chain_para_id)
977
        .map_err(|e| format!("Failed to read latest author: {}", e))?
978
        .is_none();
979

            
980
    if full_sync_needed {
981
        Ok(SyncMode::Full)
982
    } else {
983
        Ok(SyncMode::Warp)
984
    }
985
}
986

            
987
async fn get_latest_container_block_number_from_orchestrator(
988
    orchestrator_chain_interface: &Arc<dyn OrchestratorChainInterface>,
989
    orchestrator_block_hash: PHash,
990
    container_chain_para_id: ParaId,
991
) -> Option<u32> {
992
    // Get the container chain's latest block from orchestrator chain and compare with client's one
993
    orchestrator_chain_interface
994
        .latest_block_number(orchestrator_block_hash, container_chain_para_id)
995
        .await
996
        .unwrap_or_default()
997
}
998

            
999
#[derive(Debug)]
#[allow(dead_code)]
enum DbRemovalReason {
    HighBlockDiff {
        best_block_number_db: u32,
        best_block_number_onchain: u32,
    },
    GenesisHashMismatch {
        container_client_genesis_hash: H256,
        chain_spec_genesis_hash_v0: H256,
        chain_spec_genesis_hash_v1: H256,
    },
}
/// Given a container chain client, check if the database is valid. If not, returns `Some` with the
/// reason for db removal.
/// Reasons may be:
/// * High block diff: when the local db is outdated and it would take a long time to sync using full sync, we remove it to be able to use warp sync.
/// * Genesis hash mismatch, when the chain was deregistered and a different chain with the same para id was registered.
async fn db_needs_removal<RuntimeApi: MinimalContainerRuntimeApi>(
    container_chain_client: &Arc<ContainerChainClient<RuntimeApi>>,
    orchestrator_chain_interface: &Arc<dyn OrchestratorChainInterface>,
    orchestrator_block_hash: PHash,
    container_chain_para_id: ParaId,
    container_chain_cli: &ContainerChainCli,
    keep_db: bool,
) -> sc_service::error::Result<Option<DbRemovalReason>> {
    // Check block diff, only needed if keep-db is false
    if !keep_db {
        // Get latest block number from the container chain client
        let last_container_block_temp = container_chain_client.chain_info().best_number;
        if last_container_block_temp == 0 {
            // Don't remove an empty database, as it may be in the process of a warp sync
        } else if get_latest_container_block_number_from_orchestrator(
            orchestrator_chain_interface,
            orchestrator_block_hash,
            container_chain_para_id,
        )
        .await
        .unwrap_or(0)
        .abs_diff(last_container_block_temp)
            > MAX_BLOCK_DIFF_FOR_FULL_SYNC
        {
            // if the diff is big, delete db and restart using warp sync
            return Ok(Some(DbRemovalReason::HighBlockDiff {
                best_block_number_db: last_container_block_temp,
                best_block_number_onchain: last_container_block_temp,
            }));
        }
    }
    // Generate genesis hash to compare against container client's genesis hash
    let container_preloaded_genesis = container_chain_cli.preloaded_chain_spec.as_ref().unwrap();
    // Check with both state versions, but first v1 which is the latest
    let block_v1: Block =
        generate_genesis_block(&**container_preloaded_genesis, sp_runtime::StateVersion::V1)
            .map_err(|e| format!("{:?}", e))?;
    let chain_spec_genesis_hash_v1 = block_v1.header().hash();
    let container_client_genesis_hash = container_chain_client.chain_info().genesis_hash;
    if container_client_genesis_hash != chain_spec_genesis_hash_v1 {
        let block_v0: Block =
            generate_genesis_block(&**container_preloaded_genesis, sp_runtime::StateVersion::V0)
                .map_err(|e| format!("{:?}", e))?;
        let chain_spec_genesis_hash_v0 = block_v0.header().hash();
        if container_client_genesis_hash != chain_spec_genesis_hash_v0 {
            log::info!("Container genesis V0: {:?}", chain_spec_genesis_hash_v0);
            log::info!("Container genesis V1: {:?}", chain_spec_genesis_hash_v1);
            log::info!(
                "Chain spec genesis {:?} did not match with any container genesis - Restarting...",
                container_client_genesis_hash
            );
            return Ok(Some(DbRemovalReason::GenesisHashMismatch {
                container_client_genesis_hash,
                chain_spec_genesis_hash_v0,
                chain_spec_genesis_hash_v1,
            }));
        }
    }
    Ok(None)
}
/// Remove the container chain database folder. This is called with db_path:
///     `Collator2002-01/data/containers/chains/simple_container_2002/paritydb/full-container-2002`
/// but we want to delete everything under
///     `Collator2002-01/data/containers/chains/simple_container_2002`
/// So we use `delete_empty_folders_recursive` to try to remove the parent folders as well, but only
/// if they are empty. This is to avoid removing any secret keys or other important data.
fn delete_container_chain_db(db_path: &Path) {
    // Remove folder `full-container-2002`
    let _ = std::fs::remove_dir_all(db_path);
    // Remove all the empty folders inside `simple_container_2002`, including self
    if let Some(parent) = db_path.ancestors().nth(2) {
        delete_empty_folders_recursive(parent);
    }
}
/// Removes all empty folders in `path`, recursively. Then, if `path` is empty, it removes it as well.
/// Ignores any IO errors.
fn delete_empty_folders_recursive(path: &Path) {
    let entry_iter = std::fs::read_dir(path);
    let entry_iter = match entry_iter {
        Ok(x) => x,
        Err(_e) => return,
    };
    for entry in entry_iter {
        let entry = match entry {
            Ok(x) => x,
            Err(_e) => continue,
        };
        let path = entry.path();
        if path.is_dir() {
            delete_empty_folders_recursive(&path);
        }
    }
    // Try to remove dir. Returns an error if the directory is not empty, but we ignore it.
    let _ = std::fs::remove_dir(path);
}
/// Parse a list of boot nodes in `Vec<u8>` format. Invalid boot nodes are filtered out.
3
fn parse_boot_nodes_ignore_invalid(
3
    boot_nodes_raw: Vec<Vec<u8>>,
3
    container_chain_para_id: ParaId,
3
) -> Vec<MultiaddrWithPeerId> {
3
    boot_nodes_raw
3
        .into_iter()
3
        .filter_map(|x| {
3
            let x = String::from_utf8(x)
3
                .map_err(|e| {
1
                    log::debug!(
                        "Invalid boot node in container chain {}: {}",
                        container_chain_para_id,
                        e
                    );
3
                })
3
                .ok()?;
2
            x.parse::<MultiaddrWithPeerId>()
2
                .map_err(|e| {
1
                    log::debug!(
                        "Invalid boot node in container chain {}: {}",
                        container_chain_para_id,
                        e
                    )
2
                })
2
                .ok()
3
        })
3
        .collect()
3
}
pub async fn wait_for_paritydb_lock(db_path: &Path, max_timeout: Duration) -> Result<(), String> {
    let now = Instant::now();
    while now.elapsed() < max_timeout {
        let lock_held = check_paritydb_lock_held(db_path)
            .map_err(|e| format!("Failed to check if lock file is held: {}", e))?;
        if !lock_held {
            return Ok(());
        }
        sleep(Duration::from_secs(1)).await;
    }
    Err("Timeout when waiting for paritydb lock".to_string())
}
/// Given a path to a paritydb database, check if its lock file is held. This indicates that a
/// background process is still using the database, so we should wait before trying to open it.
///
/// This should be kept up to date with the way paritydb handles the lock file:
/// <https://github.com/paritytech/parity-db/blob/2b6820e310a08678d4540c044f41a93d87343ac8/src/db.rs#L215>
fn check_paritydb_lock_held(db_path: &Path) -> Result<bool, std::io::Error> {
    if !db_path.is_dir() {
        // Lock file does not exist, so it is not held
        return Ok(false);
    }
    let mut lock_path: std::path::PathBuf = db_path.to_owned();
    lock_path.push("lock");
    let lock_file = std::fs::OpenOptions::new()
        .create(true)
        .read(true)
        .write(true)
        .truncate(true)
        .open(lock_path.as_path())?;
    // Check if the lock file is busy by trying to lock it.
    // Returns err if failed to adquire the lock.
    let lock_held = lock_file.try_lock_exclusive().is_err();
    Ok(lock_held)
}
fn sort_container_folders_by_para_id(
    chains_folder_path: &Path,
) -> HashMap<Option<ParaId>, Vec<PathBuf>> {
    let mut h = HashMap::new();
    let entry_iter = std::fs::read_dir(chains_folder_path);
    let entry_iter = match entry_iter {
        Ok(x) => x,
        Err(_e) => return h,
    };
    for entry in entry_iter {
        let entry = match entry {
            Ok(x) => x,
            Err(_e) => continue,
        };
        let path = entry.path();
        if path.is_dir() {
            if let Ok(para_id) = process_container_folder_get_para_id(path.clone()) {
                h.entry(para_id).or_default().push(path);
            }
        }
    }
    h
}
fn process_container_folder_get_para_id(path: PathBuf) -> std::io::Result<Option<ParaId>> {
    // Build the path to the paritydb directory
    let paritydb_path = path.join("paritydb");
    // Check if the paritydb directory exists and is a directory
    if !paritydb_path.is_dir() {
        // If not, associate the path with `None` in the hashmap
        return Ok(None);
    }
    // Read the entries in the paritydb directory
    let entry_iter = std::fs::read_dir(&paritydb_path)?;
    let mut para_id: Option<ParaId> = None;
    // Iterate over each entry in the paritydb directory
    for entry in entry_iter {
        let entry = entry?;
        let sub_path = entry.path();
        // Only consider directories
        if !sub_path.is_dir() {
            continue;
        }
        let sub_path_file_name = match sub_path.file_name().and_then(|s| s.to_str()) {
            Some(x) => x,
            None => {
                continue;
            }
        };
        // That follow this pattern
        if !sub_path_file_name.starts_with("full-container-") {
            continue;
        }
        if let Some(id) = parse_para_id_from_folder_name(sub_path_file_name) {
            if para_id.is_some() {
                // If there is more than one folder with a para id, assume this folder is
                // corrupted and ignore it, keep it for manual deletion
                return Err(std::io::Error::new(std::io::ErrorKind::Other, ""));
            }
            para_id = Some(id);
        }
    }
    Ok(para_id)
}
// Input:
// full-container-2000
// Output:
// Some(2000)
5
fn parse_para_id_from_folder_name(folder_name: &str) -> Option<ParaId> {
    // Find last '-' in string
5
    let idx = folder_name.rfind('-')?;
    // +1 to skip the '-'
3
    let id_str = &folder_name[idx + 1..];
    // Try to parse as u32, in case of error return None
3
    let id = id_str.parse::<u32>().ok()?;
1
    Some(id.into())
5
}
#[cfg(test)]
mod tests {
    use {super::*, std::path::PathBuf};
    // Copy of ContainerChainSpawner with extra assertions for tests, and mocked spawn function.
    struct MockContainerChainSpawner {
        state: Arc<Mutex<ContainerChainSpawnerState>>,
        orchestrator_para_id: ParaId,
        collate_on_tanssi: Arc<
            dyn Fn() -> (CancellationToken, futures::channel::oneshot::Receiver<()>) + Send + Sync,
        >,
        collation_cancellation_constructs: Option<()>,
        // Keep track of the last CollateOn message, for tests
        currently_collating_on: Arc<Mutex<Option<ParaId>>>,
    }
    impl MockContainerChainSpawner {
10
        fn new() -> Self {
10
            let orchestrator_para_id = 1000.into();
10
            // The node always starts as an orchestrator chain collator
10
            let currently_collating_on = Arc::new(Mutex::new(Some(orchestrator_para_id)));
10
            let currently_collating_on2 = currently_collating_on.clone();
10
            let collate_closure = move || {
3
                let mut cco = currently_collating_on2.lock().unwrap();
3
                assert_ne!(
3
                    *cco,
3
                    Some(orchestrator_para_id),
                    "Received CollateOn message when we were already collating on this chain: {}",
                    orchestrator_para_id
                );
3
                *cco = Some(orchestrator_para_id);
3
                let (_, receiver) = futures::channel::oneshot::channel();
3
                (CancellationToken::new(), receiver)
3
            };
10
            let collate_on_tanssi: Arc<
10
                dyn Fn() -> (CancellationToken, futures::channel::oneshot::Receiver<()>)
10
                    + Send
10
                    + Sync,
10
            > = Arc::new(collate_closure);
10

            
10
            Self {
10
                state: Arc::new(Mutex::new(ContainerChainSpawnerState {
10
                    spawned_container_chains: Default::default(),
10
                    assigned_para_id: Some(orchestrator_para_id),
10
                    next_assigned_para_id: None,
10
                    failed_para_ids: Default::default(),
10
                    spawned_containers_monitor: Default::default(),
10
                })),
10
                orchestrator_para_id,
10
                collate_on_tanssi,
10
                // Some if collator starts on orchestrator chain
10
                collation_cancellation_constructs: Some(()),
10
                currently_collating_on,
10
            }
10
        }
21
        fn spawn(&self, container_chain_para_id: ParaId, start_collation: bool) {
21
            let (signal, _on_exit) = oneshot::channel();
21
            let currently_collating_on2 = self.currently_collating_on.clone();
21
            let collate_closure = move || {
13
                let mut cco = currently_collating_on2.lock().unwrap();
13
                assert_ne!(
13
                    *cco,
13
                    Some(container_chain_para_id),
                    "Received CollateOn message when we were already collating on this chain: {}",
                    container_chain_para_id
                );
13
                *cco = Some(container_chain_para_id);
13
                let (_, receiver) = futures::channel::oneshot::channel();
13
                (CancellationToken::new(), receiver)
13
            };
21
            let collate_on: Arc<
21
                dyn Fn() -> (CancellationToken, futures::channel::oneshot::Receiver<()>)
21
                    + Send
21
                    + Sync,
21
            > = Arc::new(collate_closure);
21
            // Dummy db_path for tests, is not actually used
21
            let db_path = PathBuf::from(format!("/tmp/container-{}/db", container_chain_para_id));
21

            
21
            let old = self
21
                .state
21
                .lock()
21
                .expect("poison error")
21
                .spawned_container_chains
21
                .insert(
21
                    container_chain_para_id,
21
                    ContainerChainState {
21
                        stop_handle: StopContainerChain { signal, id: 0 },
21
                        db_path,
21
                    },
21
                );
21

            
21
            assert!(
21
                old.is_none(),
                "tried to spawn a container chain that was already running: {}",
                container_chain_para_id
            );
21
            if start_collation {
13
                let (_cancellation_token, _exit_receiver) = collate_on();
13
            }
21
        }
15
        fn stop(&self, container_chain_para_id: ParaId) {
15
            let stop_handle = self
15
                .state
15
                .lock()
15
                .expect("poison error")
15
                .spawned_container_chains
15
                .remove(&container_chain_para_id);
15

            
15
            match stop_handle {
15
                Some(_stop_handle) => {
15
                    log::info!("Stopping container chain {}", container_chain_para_id);
                }
                None => {
                    panic!(
                        "Tried to stop a container chain that is not running: {}",
                        container_chain_para_id
                    );
                }
            }
            // Update currently_collating_on, if we stopped the chain we are no longer collating there
15
            let mut lco = self.currently_collating_on.lock().unwrap();
15
            if *lco == Some(container_chain_para_id) {
7
                *lco = None;
8
            }
15
        }
35
        fn handle_update_assignment(&mut self, current: Option<ParaId>, next: Option<ParaId>) {
35
            let HandleUpdateAssignmentResult {
35
                chains_to_stop,
35
                chains_to_start,
35
                need_to_restart,
35
            } = handle_update_assignment_state_change(
35
                &mut self.state.lock().unwrap(),
35
                self.orchestrator_para_id,
35
                current,
35
                next,
35
            );
35

            
35
            if current != Some(self.orchestrator_para_id) {
                // If not assigned to orchestrator chain anymore, we need to stop the collator process
27
                let mut cco = self.currently_collating_on.lock().unwrap();
27
                if *cco == Some(self.orchestrator_para_id) {
10
                    *cco = None;
17
                }
27
                self.collation_cancellation_constructs = None;
8
            } else if self.collation_cancellation_constructs.is_none() {
3
                let (_cancellation_token, _exit_notification_receiver) = (self.collate_on_tanssi)();
3
                self.collation_cancellation_constructs = Some(());
5
            }
            // Assert we never start and stop the same container chain
56
            for para_id in &chains_to_start {
21
                if !need_to_restart {
4
                    assert!(
4
                        !chains_to_stop.contains(para_id),
                        "Tried to start and stop same container chain: {}",
                        para_id
                    );
                } else {
                    // Will try to start and stop container chain with id "current" or "next", so ignore that
17
                    if Some(*para_id) != current && Some(*para_id) != next {
                        assert!(
                            !chains_to_stop.contains(para_id),
                            "Tried to start and stop same container chain: {}",
                            para_id
                        );
17
                    }
                }
            }
            // Assert we never start or stop the orchestrator chain
35
            assert!(!chains_to_start.contains(&self.orchestrator_para_id));
35
            assert!(!chains_to_stop.contains(&self.orchestrator_para_id));
            // Stop all container chains that are no longer needed
50
            for para_id in chains_to_stop {
15
                self.stop(para_id);
15
            }
            // Start all new container chains (usually 1)
56
            for para_id in chains_to_start {
21
                // Edge case: when starting the node it may be assigned to a container chain, so we need to
21
                // start a container chain already collating.
21
                let start_collation = Some(para_id) == current;
21
                self.spawn(para_id, start_collation);
21
            }
            // Assert that if we are currently assigned to a container chain, we are collating there
35
            if let Some(para_id) = current {
24
                self.assert_collating_on(Some(para_id));
24
            } else {
11
                self.assert_collating_on(None);
11
            }
35
        }
        #[track_caller]
71
        fn assert_collating_on(&self, para_id: Option<ParaId>) {
71
            let currently_collating_on = *self.currently_collating_on.lock().unwrap();
71
            assert_eq!(currently_collating_on, para_id);
71
        }
        #[track_caller]
36
        fn assert_running_chains(&self, para_ids: &[ParaId]) {
36
            let mut actually_running: Vec<ParaId> = self
36
                .state
36
                .lock()
36
                .unwrap()
36
                .spawned_container_chains
36
                .keys()
36
                .cloned()
36
                .collect();
36
            actually_running.sort();
36
            let mut should_be_running = para_ids.to_vec();
36
            should_be_running.sort();
36
            assert_eq!(actually_running, should_be_running);
36
        }
    }
    #[test]
1
    fn starts_collating_on_tanssi() {
1
        let mut m = MockContainerChainSpawner::new();
1
        m.assert_collating_on(Some(1000.into()));
1
        m.assert_running_chains(&[]);
1

            
1
        m.handle_update_assignment(None, None);
1
        m.assert_collating_on(None);
1
        m.assert_running_chains(&[]);
1
    }
    #[test]
1
    fn assigned_to_orchestrator_chain() {
1
        let mut m = MockContainerChainSpawner::new();
1

            
1
        m.handle_update_assignment(Some(1000.into()), Some(1000.into()));
1
        m.assert_collating_on(Some(1000.into()));
1
        m.assert_running_chains(&[]);
1

            
1
        m.handle_update_assignment(Some(1000.into()), None);
1
        m.assert_collating_on(Some(1000.into()));
1
        m.assert_running_chains(&[]);
1

            
1
        m.handle_update_assignment(None, None);
1
        m.assert_collating_on(None);
1
        m.assert_running_chains(&[]);
1

            
1
        m.handle_update_assignment(None, Some(1000.into()));
1
        m.assert_collating_on(None);
1
        m.assert_running_chains(&[]);
1

            
1
        m.handle_update_assignment(Some(1000.into()), Some(1000.into()));
1
        m.assert_collating_on(Some(1000.into()));
1
        m.assert_running_chains(&[]);
1
    }
    #[test]
1
    fn assigned_to_container_chain() {
1
        let mut m = MockContainerChainSpawner::new();
1

            
1
        m.handle_update_assignment(Some(2000.into()), Some(2000.into()));
1
        m.assert_collating_on(Some(2000.into()));
1
        m.assert_running_chains(&[2000.into()]);
1

            
1
        m.handle_update_assignment(Some(2000.into()), None);
1
        m.assert_collating_on(Some(2000.into()));
1
        m.assert_running_chains(&[2000.into()]);
1

            
1
        m.handle_update_assignment(None, None);
1
        m.assert_collating_on(None);
1
        m.assert_running_chains(&[]);
1

            
1
        m.handle_update_assignment(None, Some(2000.into()));
1
        m.assert_collating_on(None);
1
        m.assert_running_chains(&[2000.into()]);
1

            
1
        m.handle_update_assignment(Some(2000.into()), Some(2000.into()));
1
        m.assert_collating_on(Some(2000.into()));
1
        m.assert_running_chains(&[2000.into()]);
1
    }
    #[test]
1
    fn spawn_container_chains() {
1
        let mut m = MockContainerChainSpawner::new();
1

            
1
        m.handle_update_assignment(Some(1000.into()), Some(2000.into()));
1
        m.assert_collating_on(Some(1000.into()));
1
        m.assert_running_chains(&[2000.into()]);
1

            
1
        m.handle_update_assignment(Some(2000.into()), Some(2000.into()));
1
        m.assert_collating_on(Some(2000.into()));
1
        m.assert_running_chains(&[2000.into()]);
1

            
1
        m.handle_update_assignment(Some(2000.into()), Some(2001.into()));
1
        m.assert_collating_on(Some(2000.into()));
1
        m.assert_running_chains(&[2000.into(), 2001.into()]);
1

            
1
        m.handle_update_assignment(Some(2001.into()), Some(2001.into()));
1
        m.assert_collating_on(Some(2001.into()));
1
        m.assert_running_chains(&[2001.into()]);
1

            
1
        m.handle_update_assignment(Some(2001.into()), Some(1000.into()));
1
        m.assert_collating_on(Some(2001.into()));
1
        m.assert_running_chains(&[2001.into()]);
1

            
1
        m.handle_update_assignment(Some(1000.into()), Some(1000.into()));
1
        m.assert_collating_on(Some(1000.into()));
1
        m.assert_running_chains(&[]);
1
    }
    #[test]
1
    fn swap_current_next() {
1
        // Going from (2000, 2001) to (2001, 2000) shouldn't start or stop any container chains
1
        let mut m: MockContainerChainSpawner = MockContainerChainSpawner::new();
1

            
1
        m.handle_update_assignment(Some(2000.into()), Some(2001.into()));
1
        m.assert_collating_on(Some(2000.into()));
1
        m.assert_running_chains(&[2000.into(), 2001.into()]);
1

            
1
        m.handle_update_assignment(Some(2001.into()), Some(2000.into()));
1
        m.assert_collating_on(Some(2001.into()));
1
        m.assert_running_chains(&[2000.into(), 2001.into()]);
1
    }
    #[test]
1
    fn stop_collating_orchestrator() {
1
        let mut m: MockContainerChainSpawner = MockContainerChainSpawner::new();
1

            
1
        m.handle_update_assignment(Some(1000.into()), Some(1000.into()));
1
        m.assert_collating_on(Some(1000.into()));
1
        m.assert_running_chains(&[]);
1

            
1
        m.handle_update_assignment(Some(1000.into()), None);
1
        m.assert_collating_on(Some(1000.into()));
1
        m.assert_running_chains(&[]);
1

            
1
        m.handle_update_assignment(None, None);
1
        m.assert_collating_on(None);
1
        m.assert_running_chains(&[]);
1

            
1
        m.handle_update_assignment(Some(1000.into()), None);
1
        m.assert_collating_on(Some(1000.into()));
1
        m.assert_running_chains(&[]);
1
    }
    #[test]
1
    fn stop_collating_container() {
1
        let mut m: MockContainerChainSpawner = MockContainerChainSpawner::new();
1

            
1
        m.handle_update_assignment(Some(2000.into()), None);
1
        m.assert_collating_on(Some(2000.into()));
1
        m.assert_running_chains(&[2000.into()]);
1

            
1
        m.handle_update_assignment(None, None);
1
        m.assert_collating_on(None);
1
        m.assert_running_chains(&[]);
1

            
1
        m.handle_update_assignment(None, Some(2000.into()));
1
        m.assert_collating_on(None);
1
        m.assert_running_chains(&[2000.into()]);
1

            
1
        // This will send a CollateOn message to the same chain as the last CollateOn,
1
        // but this is needed because that chain has been stopped
1
        m.handle_update_assignment(Some(2000.into()), Some(2000.into()));
1
        m.assert_collating_on(Some(2000.into()));
1
        m.assert_running_chains(&[2000.into()]);
1
    }
    #[test]
1
    fn stop_collating_container_start_immediately() {
1
        let mut m: MockContainerChainSpawner = MockContainerChainSpawner::new();
1

            
1
        m.handle_update_assignment(Some(2000.into()), None);
1
        m.assert_collating_on(Some(2000.into()));
1
        m.assert_running_chains(&[2000.into()]);
1

            
1
        m.handle_update_assignment(None, None);
1
        m.assert_collating_on(None);
1
        m.assert_running_chains(&[]);
1

            
1
        // This will start the chain already collating
1
        m.handle_update_assignment(Some(2000.into()), Some(2000.into()));
1
        m.assert_collating_on(Some(2000.into()));
1
        m.assert_running_chains(&[2000.into()]);
1
    }
    #[test]
1
    fn stop_all_chains() {
1
        let mut m: MockContainerChainSpawner = MockContainerChainSpawner::new();
1

            
1
        m.handle_update_assignment(Some(2000.into()), Some(2001.into()));
1
        m.assert_collating_on(Some(2000.into()));
1
        m.assert_running_chains(&[2000.into(), 2001.into()]);
1

            
1
        m.handle_update_assignment(None, None);
1
        m.assert_collating_on(None);
1
        m.assert_running_chains(&[]);
1
    }
    #[test]
1
    fn keep_collating_on_container() {
1
        let mut m: MockContainerChainSpawner = MockContainerChainSpawner::new();
1

            
1
        m.handle_update_assignment(Some(2000.into()), None);
1
        m.assert_collating_on(Some(2000.into()));
1
        m.assert_running_chains(&[2000.into()]);
1

            
1
        m.handle_update_assignment(None, Some(2000.into()));
1
        m.assert_collating_on(None);
1
        m.assert_running_chains(&[2000.into()]);
1

            
1
        m.handle_update_assignment(Some(2000.into()), Some(2000.into()));
1
        m.assert_collating_on(Some(2000.into()));
1
        m.assert_running_chains(&[2000.into()]);
1
    }
    #[test]
1
    fn invalid_boot_nodes_are_ignored() {
1
        let para_id = 100.into();
1
        let bootnode1 =
1
            b"/ip4/127.0.0.1/tcp/33049/ws/p2p/12D3KooWHVMhQDHBpj9vQmssgyfspYecgV6e3hH1dQVDUkUbCYC9"
1
                .to_vec();
1
        assert_eq!(
1
            parse_boot_nodes_ignore_invalid(vec![b"A".to_vec()], para_id),
1
            vec![]
1
        );
1
        assert_eq!(
1
            parse_boot_nodes_ignore_invalid(vec![b"\xff".to_vec()], para_id),
1
            vec![]
1
        );
        // Valid boot nodes are not ignored
1
        assert_eq!(
1
            parse_boot_nodes_ignore_invalid(vec![bootnode1], para_id).len(),
1
            1
1
        );
1
    }
    #[test]
1
    fn path_ancestors() {
1
        // Test the implementation of `delete_container_chain_db`
1
        let db_path = PathBuf::from("/tmp/zombienet/Collator2002-01/data/containers/chains/simple_container_2002/paritydb/full-container-2002");
1
        let parent = db_path.ancestors().nth(2).unwrap();
1

            
1
        assert_eq!(
1
            parent,
1
            PathBuf::from(
1
                "/tmp/zombienet/Collator2002-01/data/containers/chains/simple_container_2002"
1
            )
1
        )
1
    }
    #[test]
1
    fn para_id_from_folder_name() {
1
        assert_eq!(parse_para_id_from_folder_name(""), None,);
1
        assert_eq!(parse_para_id_from_folder_name("full"), None,);
1
        assert_eq!(parse_para_id_from_folder_name("full-container"), None,);
1
        assert_eq!(parse_para_id_from_folder_name("full-container-"), None,);
1
        assert_eq!(
1
            parse_para_id_from_folder_name("full-container-2000"),
1
            Some(ParaId::from(2000)),
1
        );
1
    }
}