Add the code for compiling node-cli for WASM-browser (#3974)

* Extract CLI to separate module in node/cli

* Make node/cli compile for WASM

* More work on node/cli browser

* More work on browser node

* More work

* More work

* Purge a bit the CI script

* More clean up

* Remove substrate-finality-grandpa from the CI

Its tests use tokio, which fails to compile.

* Address review

* Add rocksdb feature to the service

* Fix substrate-service WASM CI

* Apply suggestions from code review

Co-Authored-By: Bastian Köcher <bkchr@users.noreply.github.com>

* Don't WASM-compile substrate-service altogether

substrate/core/cli/Cargo.toml

@@ -28,7 +28,7 @@ header-metadata = { package = "substrate-header-metadata", path = "../../core/cl
 network = { package = "substrate-network", path = "../../core/network" }
 sr-primitives = { path = "../../core/sr-primitives" }
 primitives = { package = "substrate-primitives", path = "../../core/primitives" }
-service = { package = "substrate-service", path = "../../core/service" }
+service = { package = "substrate-service", path = "../../core/service", default-features = false }
 state-machine = { package = "substrate-state-machine", path = "../../core/state-machine" }
 substrate-telemetry = { path = "../../core/telemetry" }
 keyring = { package = "substrate-keyring", path = "../keyring" }

substrate/core/service/Cargo.toml

@@ -4,6 +4,12 @@ version = "2.0.0"
 authors = ["Parity Technologies <admin@parity.io>"]
 edition = "2018"
 
+[features]
+default = ["rocksdb"]
+# The RocksDB feature activates the RocksDB database backend. If it is not activated, and you pass
+# a path to a database, an error will be produced at runtime.
+rocksdb = ["client_db/kvdb-rocksdb"]
+
 [dependencies]
 derive_more = "0.15.0"
 futures = "0.1.29"
@@ -29,7 +35,7 @@ consensus_common = { package = "substrate-consensus-common", path = "../../core/
 network = { package = "substrate-network", path = "../../core/network" }
 chain-spec = { package = "substrate-chain-spec", path = "../chain-spec" }
 client = { package = "substrate-client", path = "../../core/client" }
-client_db = { package = "substrate-client-db", path = "../../core/client/db", features = ["kvdb-rocksdb"] }
+client_db = { package = "substrate-client-db", path = "../../core/client/db" }
 codec = { package = "parity-scale-codec", version = "1.0.0" }
 substrate-executor = { path = "../../core/executor" }
 transaction_pool = { package = "substrate-transaction-pool", path = "../../core/transaction-pool" }

substrate/core/service/src/lib.rs

@@ -541,15 +541,16 @@ fn start_rpc_servers<C, G, E, H: FnMut() -> rpc_servers::RpcHandler<rpc::Metadat
 
 /// Starts RPC servers that run in their own thread, and returns an opaque object that keeps them alive.
 #[cfg(target_os = "unknown")]
-fn start_rpc_servers<C, G, E, H: FnMut() -> components::RpcHandler>(
+fn start_rpc_servers<C, G, E, H: FnMut() -> rpc_servers::RpcHandler<rpc::Metadata>>(
 	_: &Configuration<C, G, E>,
 	_: H
-) -> Result<Box<std::any::Any + Send + Sync>, error::Error> {
+) -> Result<Box<dyn std::any::Any + Send + Sync>, error::Error> {
 	Ok(Box::new(()))
 }
 
 /// An RPC session. Used to perform in-memory RPC queries (ie. RPC queries that don't go through
 /// the HTTP or WebSockets server).
+#[derive(Clone)]
 pub struct RpcSession {
 	metadata: rpc::Metadata,
 }

substrate/core/service/test/Cargo.toml

@@ -12,7 +12,7 @@ log = "0.4.8"
 env_logger = "0.7.0"
 fdlimit = "0.1.1"
 futures03 = { package = "futures-preview", version = "=0.3.0-alpha.19", features = ["compat"] }
-service = { package = "substrate-service", path = "../../../core/service" }
+service = { package = "substrate-service", path = "../../../core/service", default-features = false }
 network = { package = "substrate-network", path = "../../../core/network" }
 consensus = { package = "substrate-consensus-common", path = "../../../core/consensus/common" }
 client = { package = "substrate-client", path = "../../../core/client" }