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/service/src/config.rs

@@ -17,7 +17,7 @@
 //! Service configuration.
 
 pub use sc_client::ExecutionStrategies;
-pub use sc_client_db::{kvdb::KeyValueDB, PruningMode};
+pub use sc_client_db::{Database, PruningMode, DatabaseSettingsSrc as DatabaseConfig};
 pub use sc_network::Multiaddr;
 pub use sc_network::config::{ExtTransport, MultiaddrWithPeerId, NetworkConfiguration, Role, NodeKeyConfig};
 pub use sc_executor::WasmExecutionMethod;
@@ -124,21 +124,6 @@ impl KeystoreConfig {
 	}
 }
 
-/// Configuration of the database of the client.
-#[derive(Clone)]
-pub enum DatabaseConfig {
-	/// Database file at a specific path. Recommended for most uses.
-	Path {
-		/// Path to the database.
-		path: PathBuf,
-		/// Cache Size for internal database in MiB
-		cache_size: usize,
-	},
-
-	/// A custom implementation of an already-open database.
-	Custom(Arc<dyn KeyValueDB>),
-}
-
 /// Configuration of the Prometheus endpoint.
 #[derive(Clone)]
 pub struct PrometheusConfig {