New database trait (#5549)

* Introduce trait

* The trait

* Generic

* Basic impls.

* Remove unneeded bounds

* Minor changes

* Switch over to the new DB trait

* Integrated parity-db and added CLI for db selection

* Default impl.

* Fix logs.

* Started integrating subdb

* Apply suggestions from code review

Co-Authored-By: Cecile Tonglet <cecile@parity.io>

* Apply suggestions from code review

Co-Authored-By: Nikolay Volf <nikvolf@gmail.com>

* Enable subdb

* Bump parity-db

* Fixed CLI macro

* Fixed browser build

* Fixed features

* Sort out features

* Use parity-db from crates.io

* Typo

Co-authored-by: arkpar <arkady.paronyan@gmail.com>
Co-authored-by: Cecile Tonglet <cecile@parity.io>
Co-authored-by: Nikolay Volf <nikvolf@gmail.com>

substrate/client/cli/src/arg_enums.rs

@@ -122,6 +122,20 @@ impl ExecutionStrategy {
 	}
 }
 
+arg_enum! {
+	/// Database backend
+	#[allow(missing_docs)]
+	#[derive(Debug, Clone, Copy)]
+	pub enum Database {
+		// Facebooks RocksDB
+		RocksDb,
+		// Subdb. https://github.com/paritytech/subdb/
+		SubDb,
+		// ParityDb. https://github.com/paritytech/parity-db/
+		ParityDb,
+	}
+}
+
 /// Default value for the `--execution-syncing` parameter.
 pub const DEFAULT_EXECUTION_SYNCING: ExecutionStrategy = ExecutionStrategy::NativeElseWasm;
 /// Default value for the `--execution-import-block` parameter.

substrate/client/cli/src/commands/export_blocks_cmd.rs

@@ -74,7 +74,7 @@ impl ExportBlocksCmd {
 		<<<BB as BlockT>::Header as HeaderT>::Number as std::str::FromStr>::Err: std::fmt::Debug,
 		<BB as BlockT>::Hash: std::str::FromStr,
 	{
-		if let DatabaseConfig::Path { ref path, .. } = &config.database {
+		if let DatabaseConfig::RocksDb { ref path, .. } = &config.database {
 			info!("DB path: {}", path.display());
 		}
 

substrate/client/cli/src/commands/mod.rs

@@ -204,9 +204,16 @@ macro_rules! substrate_cli_subcommands {
 				&self,
 				base_path: &::std::path::PathBuf,
 				cache_size: usize,
+				database: $crate::Database,
 			) -> $crate::Result<::sc_service::config::DatabaseConfig> {
 				match self {
-					$($enum::$variant(cmd) => cmd.database_config(base_path, cache_size)),*
+					$($enum::$variant(cmd) => cmd.database_config(base_path, cache_size, database)),*
+				}
+			}
+
+			fn database(&self) -> $crate::Result<::std::option::Option<$crate::Database>> {
+				match self {
+					$($enum::$variant(cmd) => cmd.database()),*
 				}
 			}
 

substrate/client/cli/src/commands/purge_chain_cmd.rs

@@ -39,7 +39,7 @@ impl PurgeChainCmd {
 	/// Run the purge command
 	pub fn run(&self, config: Configuration) -> error::Result<()> {
 		let db_path = match &config.database {
-			DatabaseConfig::Path { path, .. } => path,
+			DatabaseConfig::RocksDb { path, .. } => path,
 			_ => {
 				eprintln!("Cannot purge custom database implementation");
 				return Ok(());

substrate/client/cli/src/config.rs

@@ -21,6 +21,7 @@ use crate::{
 	init_logger, ImportParams, KeystoreParams, NetworkParams, NodeKeyParams,
 	PruningParams, SharedParams, SubstrateCli,
 };
+use crate::arg_enums::Database;
 use app_dirs::{AppDataType, AppInfo};
 use names::{Generator, Name};
 use sc_service::config::{
@@ -152,11 +153,26 @@ pub trait CliConfiguration: Sized {
 			.unwrap_or(Default::default()))
 	}
 
+	/// Get the database backend variant.
+	///
+	/// By default this is retrieved from `ImportParams` if it is available. Otherwise its `None`.
+	fn database(&self) -> Result<Option<Database>> {
+		Ok(self.import_params().map(|x| x.database()))
+	}
+
 	/// Get the database configuration.
 	///
 	/// By default this is retrieved from `SharedParams`
-	fn database_config(&self, base_path: &PathBuf, cache_size: usize) -> Result<DatabaseConfig> {
-		Ok(self.shared_params().database_config(base_path, cache_size))
+	fn database_config(&self,
+		base_path: &PathBuf,
+		cache_size: usize,
+		database: Database,
+	) -> Result<DatabaseConfig> {
+		Ok(self.shared_params().database_config(
+			base_path,
+			cache_size,
+			database,
+		))
 	}
 
 	/// Get the state cache size.
@@ -376,6 +392,7 @@ pub trait CliConfiguration: Sized {
 		let net_config_dir = config_dir.join(DEFAULT_NETWORK_CONFIG_PATH);
 		let client_id = C::client_id();
 		let database_cache_size = self.database_cache_size()?.unwrap_or(128);
+		let database = self.database()?.unwrap_or(Database::RocksDb);
 		let node_key = self.node_key(&net_config_dir)?;
 		let role = self.role(is_dev)?;
 		let max_runtime_instances = self.max_runtime_instances()?.unwrap_or(8);
@@ -394,7 +411,7 @@ pub trait CliConfiguration: Sized {
 				node_key,
 			)?,
 			keystore: self.keystore_config(&config_dir)?,
-			database: self.database_config(&config_dir, database_cache_size)?,
+			database: self.database_config(&config_dir, database_cache_size, database)?,
 			state_cache_size: self.state_cache_size()?,
 			state_cache_child_ratio: self.state_cache_child_ratio()?,
 			pruning: self.pruning(is_dev, &role)?,

substrate/client/cli/src/params/import_params.rs

@@ -17,7 +17,7 @@
 use crate::arg_enums::{
 	ExecutionStrategy, TracingReceiver, WasmExecutionMethod, DEFAULT_EXECUTION_BLOCK_CONSTRUCTION,
 	DEFAULT_EXECUTION_IMPORT_BLOCK, DEFAULT_EXECUTION_OFFCHAIN_WORKER, DEFAULT_EXECUTION_OTHER,
-	DEFAULT_EXECUTION_SYNCING,
+	DEFAULT_EXECUTION_SYNCING, Database,
 };
 use crate::params::PruningParams;
 use crate::Result;
@@ -54,6 +54,16 @@ pub struct ImportParams {
 	#[structopt(flatten)]
 	pub execution_strategies: ExecutionStrategiesParams,
 
+	/// Select database backend to use.
+	#[structopt(
+		long = "database",
+		alias = "db",
+		value_name = "DB",
+		case_insensitive = true,
+		default_value = "RocksDb"
+	)]
+	pub database: Database,
+
 	/// Limit the memory the database cache can use.
 	#[structopt(long = "db-cache", value_name = "MiB")]
 	pub database_cache_size: Option<usize>,
@@ -132,6 +142,11 @@ impl ImportParams {
 	pub fn database_cache_size(&self) -> Option<usize> {
 		self.database_cache_size
 	}
+
+	/// Limit the memory the database cache can use.
+	pub fn database(&self) -> Database {
+		self.database
+	}
 }
 
 /// Execution strategies parameters.

substrate/client/cli/src/params/shared_params.rs

@@ -17,9 +17,7 @@
 use sc_service::config::DatabaseConfig;
 use std::path::PathBuf;
 use structopt::StructOpt;
-
-/// default sub directory to store database
-const DEFAULT_DB_CONFIG_PATH: &'static str = "db";
+use crate::arg_enums::Database;
 
 /// Shared parameters used by all `CoreParams`.
 #[derive(Debug, StructOpt, Clone)]
@@ -79,10 +77,19 @@ impl SharedParams {
 		&self,
 		base_path: &PathBuf,
 		cache_size: usize,
+		database: Database,
 	) -> DatabaseConfig {
-		DatabaseConfig::Path {
-			path: base_path.join(DEFAULT_DB_CONFIG_PATH),
-			cache_size,
+		match database {
+			Database::RocksDb => DatabaseConfig::RocksDb {
+				path: base_path.join("db"),
+				cache_size,
+			},
+			Database::SubDb => DatabaseConfig::SubDb {
+				path: base_path.join("subdb"),
+			},
+			Database::ParityDb => DatabaseConfig::ParityDb {
+				path: base_path.join("paritydb"),
+			},
 		}
 	}