Use global Tokio runtime (#543)

mimblewimble · Dec 15, 2020 · f4f4184 · f4f4184
1 parent 92c5918
commit f4f4184
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Showing 5 changed files with 27 additions and 34 deletions.
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/impls/Cargo.toml b/impls/Cargo.toml
@@ -23,7 +23,7 @@ ring = "0.16"
 tokio = { version = "0.2", features = ["full"] }
 uuid = { version = "0.8", features = ["serde", "v4"] }
 chrono = { version = "0.4.11", features = ["serde"] }
-crossbeam-utils = "0.7"
+lazy_static = "1.4"
 
 #http client (copied from grin)
 http = "0.2"

diff --git a/impls/src/client_utils/client.rs b/impls/src/client_utils/client.rs
@@ -15,19 +15,35 @@
 //! High level JSON/HTTP client API
 
 use crate::util::to_base64;
-use crossbeam_utils::thread::scope;
 use failure::{Backtrace, Context, Fail, ResultExt};
 use hyper::body;
 use hyper::header::{ACCEPT, AUTHORIZATION, CONTENT_TYPE, USER_AGENT};
 use hyper::{self, Body, Client as HyperClient, Request, Uri};
 use hyper_rustls;
 use hyper_timeout::TimeoutConnector;
+use lazy_static::lazy_static;
 use serde::{Deserialize, Serialize};
 use serde_json;
 use std::fmt::{self, Display};
 use std::net::SocketAddr;
+use std::sync::{Arc, Mutex};
 use std::time::Duration;
-use tokio::runtime::Builder;
+use tokio::runtime::{Builder, Runtime};
+
+// Global Tokio runtime.
+// Needs a `Mutex` because `Runtime::block_on` requires mutable access.
+// Tokio v0.3 requires immutable self, but we are waiting on upstream
+// updates before we can upgrade.
+// See: https://github.com/seanmonstar/reqwest/pull/1076
+lazy_static! {
+	pub static ref RUNTIME: Arc<Mutex<Runtime>> = Arc::new(Mutex::new(
+		Builder::new()
+			.threaded_scheduler()
+			.enable_all()
+			.build()
+			.unwrap()
+	));
+}
 
 /// Errors that can be returned by an ApiEndpoint implementation.
 #[derive(Debug)]
@@ -323,18 +339,9 @@ impl Client {
 	}
 
 	pub fn send_request(&self, req: Request<Body>) -> Result<String, Error> {
-		let task = self.send_request_async(req);
-		scope(|s| {
-			let handle = s.spawn(|_| {
-				let mut rt = Builder::new()
-					.basic_scheduler()
-					.enable_all()
-					.build()
-					.context(ErrorKind::Internal("can't create Tokio runtime".to_owned()))?;
-				rt.block_on(task)
-			});
-			handle.join().unwrap()
-		})
-		.unwrap()
+		RUNTIME
+			.lock()
+			.unwrap()
+			.block_on(self.send_request_async(req))
 	}
 }
diff --git a/impls/src/client_utils/mod.rs b/impls/src/client_utils/mod.rs
@@ -15,4 +15,4 @@
 mod client;
 pub mod json_rpc;
 
-pub use client::{Client, Error as ClientError};
+pub use client::{Client, Error as ClientError, RUNTIME};
diff --git a/impls/src/node_clients/http.rs b/impls/src/node_clients/http.rs
@@ -17,14 +17,12 @@
 use crate::api::{self, LocatedTxKernel, OutputListing, OutputPrintable};
 use crate::core::core::{Transaction, TxKernel};
 use crate::libwallet::{NodeClient, NodeVersionInfo};
-use crossbeam_utils::thread::scope;
 use futures::stream::FuturesUnordered;
 use futures::TryStreamExt;
 use std::collections::HashMap;
 use std::env;
-use tokio::runtime::Builder;
 
-use crate::client_utils::Client;
+use crate::client_utils::{Client, RUNTIME};
 use crate::libwallet;
 use crate::util::secp::pedersen;
 use crate::util::ToHex;
@@ -251,19 +249,7 @@ impl NodeClient for HTTPNodeClient {
 			task.try_collect().await
 		};
 
-		let res = scope(|s| {
-			let handle = s.spawn(|_| {
-				let mut rt = Builder::new()
-					.threaded_scheduler()
-					.enable_all()
-					.build()
-					.unwrap();
-				let res: Result<Vec<Response>, _> = rt.block_on(task);
-				res
-			});
-			handle.join().unwrap()
-		})
-		.unwrap();
+		let res: Result<Vec<Response>, _> = RUNTIME.lock().unwrap().block_on(task);
 
 		let results: Vec<OutputPrintable> = match res {
 			Ok(resps) => {