lib.rs

// This file is part of Substrate.

// Copyright (C) 2020-2022 Parity Technologies (UK) Ltd.
// SPDX-License-Identifier: Apache-2.0

// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// 	http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

//! # Remote Externalities
//!
//! An equivalent of `sp_io::TestExternalities` that can load its state from a remote substrate
//! based chain, or a local state snapshot file.

use codec::{Decode, Encode};

use jsonrpsee::{
	proc_macros::rpc,
	rpc_params,
	types::{traits::Client, Error as RpcError},
	ws_client::{WsClient, WsClientBuilder},
};

use log::*;
use serde::de::DeserializeOwned;
use sp_core::{
	hashing::twox_128,
	hexdisplay::HexDisplay,
	storage::{
		well_known_keys::{is_default_child_storage_key, DEFAULT_CHILD_STORAGE_KEY_PREFIX},
		ChildInfo, ChildType, PrefixedStorageKey, StorageData, StorageKey,
	},
};
pub use sp_io::TestExternalities;
use sp_runtime::traits::Block as BlockT;
use std::{
	fs,
	path::{Path, PathBuf},
};

pub mod rpc_api;

type KeyValue = (StorageKey, StorageData);
type TopKeyValues = Vec<KeyValue>;
type ChildKeyValues = Vec<(ChildInfo, Vec<KeyValue>)>;

const LOG_TARGET: &str = "remote-ext";
const DEFAULT_TARGET: &str = "wss://rpc.polkadot.io:443";
const BATCH_SIZE: usize = 1000;

#[rpc(client)]
pub trait RpcApi<Hash> {
	#[method(name = "childstate_getKeys")]
	fn child_get_keys(
		&self,
		child_key: PrefixedStorageKey,
		prefix: StorageKey,
		hash: Option<Hash>,
	) -> Result<Vec<StorageKey>, RpcError>;

	#[method(name = "childstate_getStorage")]
	fn child_get_storage(
		&self,
		child_key: PrefixedStorageKey,
		prefix: StorageKey,
		hash: Option<Hash>,
	) -> Result<StorageData, RpcError>;

	#[method(name = "state_getStorage")]
	fn get_storage(&self, prefix: StorageKey, hash: Option<Hash>) -> Result<StorageData, RpcError>;

	#[method(name = "state_getKeysPaged")]
	fn get_keys_paged(
		&self,
		prefix: Option<StorageKey>,
		count: u32,
		start_key: Option<StorageKey>,
		hash: Option<Hash>,
	) -> Result<Vec<StorageKey>, RpcError>;

	#[method(name = "chain_getFinalizedHead")]
	fn finalized_head(&self) -> Result<Hash, RpcError>;
}

/// The execution mode.
#[derive(Clone)]
pub enum Mode<B: BlockT> {
	/// Online. Potentially writes to a cache file.
	Online(OnlineConfig<B>),
	/// Offline. Uses a state snapshot file and needs not any client config.
	Offline(OfflineConfig),
	/// Prefer using a cache file if it exists, else use a remote server.
	OfflineOrElseOnline(OfflineConfig, OnlineConfig<B>),
}

impl<B: BlockT> Default for Mode<B> {
	fn default() -> Self {
		Mode::Online(OnlineConfig::default())
	}
}

/// Configuration of the offline execution.
///
/// A state snapshot config must be present.
#[derive(Clone)]
pub struct OfflineConfig {
	/// The configuration of the state snapshot file to use. It must be present.
	pub state_snapshot: SnapshotConfig,
}

impl<P: Into<PathBuf>> From<P> for SnapshotConfig {
	fn from(p: P) -> Self {
		Self { path: p.into() }
	}
}

/// Description of the transport protocol (for online execution).
#[derive(Debug)]
pub struct Transport {
	uri: String,
	client: Option<WsClient>,
}

impl Clone for Transport {
	fn clone(&self) -> Self {
		Self { uri: self.uri.clone(), client: None }
	}
}

impl From<String> for Transport {
	fn from(t: String) -> Self {
		Self { uri: t, client: None }
	}
}

/// Configuration of the online execution.
///
/// A state snapshot config may be present and will be written to in that case.
#[derive(Clone)]
pub struct OnlineConfig<B: BlockT> {
	/// The block hash at which to get the runtime state. Will be latest finalized head if not
	/// provided.
	pub at: Option<B::Hash>,
	/// An optional state snapshot file to WRITE to, not for reading. Not written if set to `None`.
	pub state_snapshot: Option<SnapshotConfig>,
	/// The pallets to scrape. If empty, entire chain state will be scraped.
	pub pallets: Vec<String>,
	/// Transport config.
	pub transport: Transport,
}

impl<B: BlockT> OnlineConfig<B> {
	/// Return rpc (ws) client.
	fn rpc_client(&self) -> &WsClient {
		self.transport
			.client
			.as_ref()
			.expect("ws client must have been initialized by now; qed.")
	}
}

impl<B: BlockT> Default for OnlineConfig<B> {
	fn default() -> Self {
		Self {
			transport: Transport { uri: DEFAULT_TARGET.to_owned(), client: None },
			at: None,
			state_snapshot: None,
			pallets: vec![],
		}
	}
}

/// Configuration of the state snapshot.
#[derive(Clone)]
pub struct SnapshotConfig {
	/// The path to the snapshot file.
	pub path: PathBuf,
}

impl SnapshotConfig {
	pub fn new<P: Into<PathBuf>>(path: P) -> Self {
		Self { path: path.into() }
	}
}

impl Default for SnapshotConfig {
	fn default() -> Self {
		Self { path: Path::new("SNAPSHOT").into() }
	}
}

/// Builder for remote-externalities.