Add async support to jsonrpc

Update the lockfiles because of the new dev dependency on futures.

Author: jamillambert

Cargo-minimal.lock

@@ -361,6 +361,94 @@ dependencies = [
  "percent-encoding",
 ]
 
+[[package]]
+name = "futures"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b147ee9d1f6d097cef9ce628cd2ee62288d963e16fb287bd9286455b241382d"
+dependencies = [
+ "futures-channel",
+ "futures-core",
+ "futures-executor",
+ "futures-io",
+ "futures-sink",
+ "futures-task",
+ "futures-util",
+]
+
+[[package]]
+name = "futures-channel"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "07bbe89c50d7a535e539b8c17bc0b49bdb77747034daa8087407d655f3f7cc1d"
+dependencies = [
+ "futures-core",
+ "futures-sink",
+]
+
+[[package]]
+name = "futures-core"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7e3450815272ef58cec6d564423f6e755e25379b217b0bc688e295ba24df6b1d"
+
+[[package]]
+name = "futures-executor"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "baf29c38818342a3b26b5b923639e7b1f4a61fc5e76102d4b1981c6dc7a7579d"
+dependencies = [
+ "futures-core",
+ "futures-task",
+ "futures-util",
+]
+
+[[package]]
+name = "futures-io"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cecba35d7ad927e23624b22ad55235f2239cfa44fd10428eecbeba6d6a717718"
+
+[[package]]
+name = "futures-macro"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e835b70203e41293343137df5c0664546da5745f82ec9b84d40be8336958447b"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "futures-sink"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c39754e157331b013978ec91992bde1ac089843443c49cbc7f46150b0fad0893"
+
+[[package]]
+name = "futures-task"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "037711b3d59c33004d3856fbdc83b99d4ff37a24768fa1be9ce3538a1cde4393"
+
+[[package]]
+name = "futures-util"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "389ca41296e6190b48053de0321d02a77f32f8a5d2461dd38762c0593805c6d6"
+dependencies = [
+ "futures-channel",
+ "futures-core",
+ "futures-io",
+ "futures-macro",
+ "futures-sink",
+ "futures-task",
+ "memchr",
+ "pin-project-lite",
+ "slab",
+]
+
 [[package]]
 name = "getrandom"
 version = "0.2.15"
@@ -472,6 +560,7 @@ version = "0.19.0"
 dependencies = [
  "base64 0.22.1",
  "bitreq",
+ "futures",
  "serde",
  "serde_json",
  "socks",
@@ -959,6 +1048,12 @@ version = "1.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
 
+[[package]]
+name = "slab"
+version = "0.4.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0c790de23124f9ab44544d7ac05d60440adc586479ce501c1d6d7da3cd8c9cf5"
+
 [[package]]
 name = "smallvec"
 version = "1.15.1"

Cargo-recent.lock

@@ -361,6 +361,94 @@ dependencies = [
  "percent-encoding",
 ]
 
+[[package]]
+name = "futures"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b147ee9d1f6d097cef9ce628cd2ee62288d963e16fb287bd9286455b241382d"
+dependencies = [
+ "futures-channel",
+ "futures-core",
+ "futures-executor",
+ "futures-io",
+ "futures-sink",
+ "futures-task",
+ "futures-util",
+]
+
+[[package]]
+name = "futures-channel"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "07bbe89c50d7a535e539b8c17bc0b49bdb77747034daa8087407d655f3f7cc1d"
+dependencies = [
+ "futures-core",
+ "futures-sink",
+]
+
+[[package]]
+name = "futures-core"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7e3450815272ef58cec6d564423f6e755e25379b217b0bc688e295ba24df6b1d"
+
+[[package]]
+name = "futures-executor"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "baf29c38818342a3b26b5b923639e7b1f4a61fc5e76102d4b1981c6dc7a7579d"
+dependencies = [
+ "futures-core",
+ "futures-task",
+ "futures-util",
+]
+
+[[package]]
+name = "futures-io"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cecba35d7ad927e23624b22ad55235f2239cfa44fd10428eecbeba6d6a717718"
+
+[[package]]
+name = "futures-macro"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e835b70203e41293343137df5c0664546da5745f82ec9b84d40be8336958447b"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "futures-sink"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c39754e157331b013978ec91992bde1ac089843443c49cbc7f46150b0fad0893"
+
+[[package]]
+name = "futures-task"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "037711b3d59c33004d3856fbdc83b99d4ff37a24768fa1be9ce3538a1cde4393"
+
+[[package]]
+name = "futures-util"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "389ca41296e6190b48053de0321d02a77f32f8a5d2461dd38762c0593805c6d6"
+dependencies = [
+ "futures-channel",
+ "futures-core",
+ "futures-io",
+ "futures-macro",
+ "futures-sink",
+ "futures-task",
+ "memchr",
+ "pin-project-lite",
+ "slab",
+]
+
 [[package]]
 name = "getrandom"
 version = "0.2.15"
@@ -472,6 +560,7 @@ version = "0.19.0"
 dependencies = [
  "base64 0.22.1",
  "bitreq",
+ "futures",
  "serde",
  "serde_json",
  "socks",
@@ -959,6 +1048,12 @@ version = "1.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
 
+[[package]]
+name = "slab"
+version = "0.4.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0c790de23124f9ab44544d7ac05d60440adc586479ce501c1d6d7da3cd8c9cf5"
+
 [[package]]
 name = "smallvec"
 version = "1.15.1"

jsonrpc/Cargo.toml

@@ -22,6 +22,10 @@ default = [ "simple_http", "simple_tcp" ]
 simple_http = [ "base64" ]
 # A transport that uses `bitreq` as the HTTP client.
 bitreq_http = [ "base64", "bitreq" ]
+# A transport that uses `bitreq` as the async HTTP client.
+bitreq_http_async = [ "base64", "bitreq", "bitreq/async", "client_async" ]
+# An async JSON-RPC client implementation.
+client_async = []
 # Basic transport over a raw TcpListener
 simple_tcp = []
 # Basic transport over a raw UnixStream
@@ -37,5 +41,8 @@ base64 = { version = "0.22.1", optional = true }
 bitreq = { version = "0.3.0", path = "../bitreq", features = ["json-using-serde"], optional = true }
 socks = { version = "0.3.4", optional = true}
 
+[dev-dependencies]
+futures = "0.3"
+
 [lints.rust]
 unexpected_cfgs = { level = "deny", check-cfg = ['cfg(jsonrpc_fuzz)'] }

jsonrpc/src/client_async.rs

@@ -1,14 +1,16 @@
 // SPDX-License-Identifier: CC0-1.0
 
-//! # Client support
+//! # Async client support
 //!
 //! Support for connecting to JSONRPC servers over HTTP, sending requests,
 //! and parsing responses.
 
 use std::borrow::Cow;
 use std::collections::HashMap;
 use std::fmt;
+use std::future::Future;
 use std::hash::{Hash, Hasher};
+use std::pin::Pin;
 use std::sync::atomic;
 
 use serde_json::value::RawValue;
@@ -17,20 +19,27 @@ use serde_json::Value;
 use crate::error::Error;
 use crate::{Request, Response};
 
-/// An interface for a transport over which to use the JSONRPC protocol.
+const JSONRPC_VERSION: &str = "2.0";
+
+/// Boxed future type used by async transports.
+pub type BoxFuture<'a, T> = Pin<Box<dyn Future<Output = T> + Send + 'a>>;
+
+/// An interface for an async transport over which to use the JSONRPC protocol.
 pub trait Transport: Send + Sync + 'static {
     /// Sends an RPC request over the transport.
-    fn send_request(&self, _: Request) -> Result<Response, Error>;
+    fn send_request<'a>(&'a self, req: Request<'a>) -> BoxFuture<'a, Result<Response, Error>>;
     /// Sends a batch of RPC requests over the transport.
-    fn send_batch(&self, _: &[Request]) -> Result<Vec<Response>, Error>;
+    fn send_batch<'a>(
+        &'a self,
+        reqs: &'a [Request<'a>],
+    ) -> BoxFuture<'a, Result<Vec<Response>, Error>>;
     /// Formats the target of this transport. I.e. the URL/socket/...
     fn fmt_target(&self, f: &mut fmt::Formatter) -> fmt::Result;
 }
 
-/// A JSON-RPC client.
+/// An async JSON-RPC client.
 ///
-/// Creates a new Client using one of the transport-specific constructors e.g.,
-/// [`Client::simple_http`] for a bare-minimum HTTP transport.
+/// Creates a new Client using one of the transport-specific constructors.
 pub struct Client {
     pub(crate) transport: Box<dyn Transport>,
     nonce: atomic::AtomicUsize,
@@ -48,11 +57,16 @@ impl Client {
     /// [`crate::arg`] or [`crate::try_arg`].
     pub fn build_request<'a>(&self, method: &'a str, params: Option<&'a RawValue>) -> Request<'a> {
         let nonce = self.nonce.fetch_add(1, atomic::Ordering::Relaxed);
-        Request { method, params, id: serde_json::Value::from(nonce), jsonrpc: Some("2.0") }
+        Request {
+            method,
+            params,
+            id: serde_json::Value::from(nonce),
+            jsonrpc: Some(JSONRPC_VERSION),
+        }
     }
 
     /// Sends a request to a client.
-    pub fn send_request(&self, request: Request) -> Result<Response, Error> {
+    pub fn send_request<'a>(&'a self, request: Request<'a>) -> BoxFuture<'a, Result<Response, Error>> {
         self.transport.send_request(request)
     }
 
@@ -65,14 +79,17 @@ impl Client {
     ///
     /// The return vector holds the response for the request at the corresponding index. If no
     /// response was provided, it's [`None`].
-    pub fn send_batch(&self, requests: &[Request]) -> Result<Vec<Option<Response>>, Error> {
+    pub async fn send_batch(
+        &self,
+        requests: &[Request<'_>],
+    ) -> Result<Vec<Option<Response>>, Error> {
         if requests.is_empty() {
             return Err(Error::EmptyBatch);
         }
 
         // If the request body is invalid JSON, the response is a single response object.
         // We ignore this case since we are confident we are producing valid JSON.
-        let responses = self.transport.send_batch(requests)?;
+        let responses = self.transport.send_batch(requests).await?;
         if responses.len() > requests.len() {
             return Err(Error::WrongBatchResponseSize);
         }
@@ -104,16 +121,16 @@ impl Client {
     ///
     /// To construct the arguments, one can use one of the shorthand methods
     /// [`crate::arg`] or [`crate::try_arg`].
-    pub fn call<R: for<'a> serde::de::Deserialize<'a>>(
+    pub async fn call<R: for<'a> serde::de::Deserialize<'a>>(
         &self,
         method: &str,
         args: Option<&RawValue>,
     ) -> Result<R, Error> {
         let request = self.build_request(method, args);
         let id = request.id.clone();
 
-        let response = self.send_request(request)?;
-        if response.jsonrpc.is_some() && response.jsonrpc != Some(From::from("2.0")) {
+        let response = self.send_request(request).await?;
+        if response.jsonrpc.is_some() && response.jsonrpc.as_deref() != Some(JSONRPC_VERSION) {
             return Err(Error::VersionMismatch);
         }
         if response.id != id {
@@ -124,7 +141,7 @@ impl Client {
     }
 }
 
-impl fmt::Debug for crate::Client {
+impl fmt::Debug for Client {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         write!(f, "jsonrpc::Client(")?;
         self.transport.fmt_target(f)?;
@@ -195,12 +212,23 @@ mod tests {
     use std::str::FromStr;
     use std::sync;
 
+    use futures::future::{err, ok};
+
     use super::*;
 
     struct DummyTransport;
     impl Transport for DummyTransport {
-        fn send_request(&self, _: Request) -> Result<Response, Error> { Err(Error::NonceMismatch) }
-        fn send_batch(&self, _: &[Request]) -> Result<Vec<Response>, Error> { Ok(vec![]) }
+        fn send_request<'a>(&'a self, _: Request<'a>) -> BoxFuture<'a, Result<Response, Error>> {
+            Box::pin(err(Error::NonceMismatch))
+        }
+
+        fn send_batch<'a>(
+            &'a self,
+            _: &'a [Request<'a>],
+        ) -> BoxFuture<'a, Result<Vec<Response>, Error>> {
+            Box::pin(ok(vec![]))
+        }
+
         fn fmt_target(&self, _: &mut fmt::Formatter) -> fmt::Result { Ok(()) }
     }