Add light client platform WASM compatible

.github/workflows/rust.yml

@@ -20,6 +20,8 @@ env:
     CARGO_TERM_COLOR: always
     # TODO: Currently pointing at latest substrate; is there a suitable binary we can pin to here?
     SUBSTRATE_URL: https://releases.parity.io/substrate/x86_64-debian:bullseye/latest/substrate/substrate
+    # Increase wasm test timeout from 20 seconds (default) to 1 minute.
+    WASM_BINDGEN_TEST_TIMEOUT: 60
 
 jobs:
     build:
@@ -70,9 +72,13 @@ jobs:
             - name: Cargo check subxt-signer
               run: cargo check -p subxt-signer
 
+            # We can't enable web features here, so no cargo hack.
+            - name: Cargo check subxt-lightclient
+              run: cargo check -p subxt-lightclient
+
             # Next, check each other package in isolation.
             - name: Cargo hack; check each feature/crate on its own
-              run: cargo hack --exclude subxt --exclude subxt-signer --exclude-all-features --each-feature check --workspace
+              run: cargo hack --exclude subxt --exclude subxt-signer --exclude subxt-lightclient --exclude-all-features --each-feature check --workspace
 
     fmt:
         name: Cargo fmt
@@ -259,11 +265,23 @@ jobs:
 
             - name: Run subxt WASM tests
               run: |
-                  substrate --dev --tmp > /dev/null 2>&1 &
+                  # `listen-addr` is used to configure p2p to accept websocket connections instead of TCP.
+                  # `node-key` provides a deterministic p2p address.
+                  substrate --dev --node-key 0000000000000000000000000000000000000000000000000000000000000001 --listen-addr /ip4/0.0.0.0/tcp/30333/ws > /dev/null 2>&1 &
+                  wasm-pack test --headless --firefox
+                  wasm-pack test --headless --chrome
+                  pkill substrate
+              working-directory: testing/wasm-rpc-tests
+
+            - name: Run subxt-lightclient WASM tests
+              run: |
+                  # `listen-addr` is used to configure p2p to accept websocket connections instead of TCP.
+                  # `node-key` provides a deterministic p2p address.
+                  substrate --dev --node-key 0000000000000000000000000000000000000000000000000000000000000001 --listen-addr /ip4/0.0.0.0/tcp/30333/ws > /dev/null 2>&1 &
                   wasm-pack test --headless --firefox
                   wasm-pack test --headless --chrome
                   pkill substrate
-              working-directory: testing/wasm-tests
+              working-directory: testing/wasm-lightclient-tests
 
             - name: Run subxt-signer WASM tests
               run: |

Cargo.toml

@@ -2,6 +2,7 @@
 members = [
     "cli",
     "codegen",
+    "lightclient",
     "testing/substrate-runner",
     "testing/test-runtime",
     "testing/integration-tests",
@@ -16,7 +17,8 @@ members = [
 # exclusive feature flags and thus can't compile with the
 # workspace:
 exclude = [
-    "testing/wasm-tests",
+    "testing/wasm-rpc-tests",
+    "testing/wasm-lightclient-tests",
     "signer/wasm-tests",
     "examples/wasm-example"
 ]
@@ -67,7 +69,7 @@ serde = { version = "1.0.171" }
 serde_json = { version = "1.0.100" }
 syn = { version = "2.0.15", features = ["full", "extra-traits"] }
 thiserror = "1.0.40"
-tokio = { version = "1.29", features = ["macros", "time", "rt-multi-thread"] }
+tokio = { version = "1.29", default-features = false }
 tracing = "0.1.34"
 tracing-wasm = "0.2.1"
 tracing-subscriber = "0.3.17"
@@ -77,10 +79,21 @@ wasm-bindgen-test = "0.3.24"
 which = "4.4.0"
 
 # Light client support:
+smoldot = { version = "0.8.0", default-features = false }
 smoldot-light = { version = "0.6.0", default-features = false }
 tokio-stream = "0.1.14"
 futures-util = "0.3.28"
 
+# Light client wasm:
+web-sys = { version = "0.3.61", features = ["BinaryType", "CloseEvent", "MessageEvent", "WebSocket"] }
+wasm-bindgen = "0.2.84"
+send_wrapper = "0.6.0"
+js-sys = "0.3.61"
+wasm-bindgen-futures = "0.4.19"
+futures-timer = "3"
+instant = { version = "0.1.12", default-features = false }
+tokio-util = "0.7.8"
+
 # Substrate crates:
 sp-core = { version = "21.0.0", default-features = false }
 sp-core-hashing = "9.0.0"
@@ -94,6 +107,7 @@ subxt-macro = { version = "0.29.0", path = "macro" }
 subxt-metadata = { version = "0.29.0", path = "metadata" }
 subxt-codegen = { version = "0.29.0", path = "codegen" }
 subxt-signer = { version = "0.29.0", path = "signer" }
+subxt-lightclient = { version = "0.29.0", path = "lightclient", default-features = false }
 test-runtime = { path = "testing/test-runtime" }
 substrate-runner = { path = "testing/substrate-runner" }
 

cli/Cargo.toml

@@ -31,4 +31,4 @@ scale-info = { workspace = true }
 scale-value = { workspace = true }
 syn = { workspace = true }
 jsonrpsee = { workspace = true, features = ["async-client", "client-ws-transport", "http-client"] }
-tokio = { workspace = true }
+tokio = { workspace = true, features = ["rt-multi-thread"] }

codegen/Cargo.toml

@@ -23,7 +23,7 @@ scale-info = { workspace = true }
 subxt-metadata = { workspace = true }
 jsonrpsee = { workspace = true, features = ["async-client", "client-ws-transport", "http-client"] }
 hex = { workspace = true }
-tokio = { workspace = true }
+tokio = { workspace = true, features = ["rt-multi-thread"] }
 thiserror = { workspace = true }
 
 [dev-dependencies]

lightclient/Cargo.toml

@@ -0,0 +1,86 @@
+[package]
+name = "subxt-lightclient"
+version.workspace = true
+authors.workspace = true
+edition.workspace = true
+rust-version.workspace = true
+publish = true
+
+license.workspace = true
+readme = "../README.md"
+repository.workspace = true
+documentation.workspace = true
+homepage.workspace = true
+description = "Light Client for chain interaction"
+keywords = ["parity", "substrate", "blockchain"]
+
+[features]
+default = ["native"]
+
+# Enable this for native (ie non web/wasm builds).
+# Exactly 1 of "web" and "native" is expected.
+native = [
+    "smoldot-light/std",
+    "tokio-stream",
+    "tokio/sync",
+    "tokio/rt",
+    "futures-util",
+]
+
+# Enable this for web/wasm builds.
+# Exactly 1 of "web" and "native" is expected.
+web = [
+    "getrandom/js",
+
+    "smoldot",
+    "smoldot-light",
+    "tokio-stream",
+    "tokio/sync",
+    "futures-util",
+
+    # For the light-client platform.
+    "wasm-bindgen-futures",
+	"futures-timer/wasm-bindgen",
+    "instant/wasm-bindgen",
+
+    # For websocket.
+    "js-sys",
+    "send_wrapper",
+    "web-sys",
+    "wasm-bindgen",
+]
+
+[dependencies]
+futures = { workspace = true }
+serde = { workspace = true, features = ["derive"] }
+serde_json = { workspace = true, features = ["raw_value"] }
+thiserror = { workspace = true }
+tracing = { workspace = true }
+
+# Light client support:
+smoldot = { workspace = true, optional = true }
+smoldot-light = { workspace = true, optional = true }
+either = { workspace = true, optional = true }
+tokio = { workspace = true, optional = true }
+tokio-stream = { workspace = true, optional = true }
+futures-util = { workspace = true, optional = true }
+js-sys = { workspace = true, optional = true }
+send_wrapper = { workspace = true, optional = true }
+web-sys = { workspace = true, optional = true }
+wasm-bindgen = { workspace = true, optional = true }
+wasm-bindgen-futures = { workspace = true, optional = true }
+futures-timer = { workspace = true, optional = true }
+instant = { workspace = true, optional = true }
+tokio-util = { workspace = true, optional = true }
+
+# Included if "web" feature is enabled, to enable its js feature.
+getrandom = { workspace = true, optional = true }
+
+[profile.dev.package.smoldot-light]
+opt-level = 2
+[profile.test.package.smoldot-light]
+opt-level = 2
+[profile.dev.package.smoldot]
+opt-level = 2
+[profile.test.package.smoldot]
+opt-level = 2

subxt/src/client/lightclient/background.rs → lightclient/src/background.rs

@@ -6,16 +6,17 @@ use futures::stream::StreamExt;
 use futures_util::future::{self, Either};
 use serde::Deserialize;
 use serde_json::value::RawValue;
-use std::{collections::HashMap, str::FromStr, sync::Arc};
+use std::{collections::HashMap, str::FromStr};
 use tokio::sync::{mpsc, oneshot};
 
-use super::LightClientError;
-use smoldot_light::{platform::default::DefaultPlatform as Platform, ChainId};
+use super::platform::PlatformType;
+use super::LightClientRpcError;
+use smoldot_light::ChainId;
 
 const LOG_TARGET: &str = "light-client-background";
 
 /// The response of an RPC method.
-pub type MethodResponse = Result<Box<RawValue>, LightClientError>;
+pub type MethodResponse = Result<Box<RawValue>, LightClientRpcError>;
 
 /// Message protocol between the front-end client that submits the RPC requests
 /// and the backend handler that produces responses from the chain.
@@ -50,7 +51,7 @@ pub enum FromSubxt {
 /// Background task data.
 pub struct BackgroundTask {
     /// Smoldot light client implementation that leverages the exposed platform.
-    client: smoldot_light::Client<Arc<Platform>>,
+    client: smoldot_light::Client<PlatformType>,
     /// The ID of the chain used to identify the chain protocol (ie. substrate).
     ///
     /// Note: A single chain is supported for a client. This aligns with the subxt's
@@ -79,7 +80,7 @@ pub struct BackgroundTask {
 
 impl BackgroundTask {
     /// Constructs a new [`BackgroundTask`].
-    pub fn new(client: smoldot_light::Client<Arc<Platform>>, chain_id: ChainId) -> BackgroundTask {
+    pub fn new(client: smoldot_light::Client<PlatformType>, chain_id: ChainId) -> BackgroundTask {
         BackgroundTask {
             client,
             chain_id,
@@ -127,7 +128,7 @@ impl BackgroundTask {
 
                     // Send the error back to frontend.
                     if sender
-                        .send(Err(LightClientError::Request(err.to_string())))
+                        .send(Err(LightClientRpcError::Request(err.to_string())))
                         .is_err()
                     {
                         tracing::warn!(
@@ -167,7 +168,7 @@ impl BackgroundTask {
 
                     // Send the error back to frontend.
                     if sub_id
-                        .send(Err(LightClientError::Request(err.to_string())))
+                        .send(Err(LightClientRpcError::Request(err.to_string())))
                         .is_err()
                     {
                         tracing::warn!(
@@ -191,7 +192,7 @@ impl BackgroundTask {
 
                 if let Some(sender) = self.requests.remove(&id) {
                     if sender
-                        .send(Err(LightClientError::Request(error.to_string())))
+                        .send(Err(LightClientRpcError::Request(error.to_string())))
                         .is_err()
                     {
                         tracing::warn!(
@@ -201,7 +202,7 @@ impl BackgroundTask {
                     }
                 } else if let Some((sub_id_sender, _)) = self.id_to_subscription.remove(&id) {
                     if sub_id_sender
-                        .send(Err(LightClientError::Request(error.to_string())))
+                        .send(Err(LightClientRpcError::Request(error.to_string())))
                         .is_err()
                     {
                         tracing::warn!(