Avoid connection-per-RPC-call again by caching connections

In general, only one request will be in flight at a time in
`lightning-block-sync`. Ideally we'd only have one connection, but
without using the `futures` mutex type.

Here we solve this narrowly for the one-request-at-a-time case by
caching the connection and takeing the connection out of the cache
while we work on it.
This commit is contained in:
Matt Corallo 2023-03-30 18:51:56 +00:00
parent 6b55df93fb
commit 9a50e301cb
2 changed files with 18 additions and 5 deletions

View file

@ -9,10 +9,12 @@ use bitcoin::hashes::hex::ToHex;
use std::convert::TryFrom;
use std::convert::TryInto;
use std::sync::Mutex;
/// A simple REST client for requesting resources using HTTP `GET`.
pub struct RestClient {
endpoint: HttpEndpoint,
client: Mutex<Option<HttpClient>>,
}
impl RestClient {
@ -20,7 +22,7 @@ impl RestClient {
///
/// The endpoint should contain the REST path component (e.g., http://127.0.0.1:8332/rest).
pub fn new(endpoint: HttpEndpoint) -> std::io::Result<Self> {
Ok(Self { endpoint })
Ok(Self { endpoint, client: Mutex::new(None) })
}
/// Requests a resource encoded in `F` format and interpreted as type `T`.
@ -28,8 +30,11 @@ impl RestClient {
where F: TryFrom<Vec<u8>, Error = std::io::Error> + TryInto<T, Error = std::io::Error> {
let host = format!("{}:{}", self.endpoint.host(), self.endpoint.port());
let uri = format!("{}/{}", self.endpoint.path().trim_end_matches("/"), resource_path);
let mut client = HttpClient::connect(&self.endpoint)?;
client.get::<F>(&uri, &host).await?.try_into()
let mut client = if let Some(client) = self.client.lock().unwrap().take() { client }
else { HttpClient::connect(&self.endpoint)? };
let res = client.get::<F>(&uri, &host).await?.try_into();
*self.client.lock().unwrap() = Some(client);
res
}
}

View file

@ -7,6 +7,8 @@ use crate::http::{HttpClient, HttpEndpoint, HttpError, JsonResponse};
use bitcoin::hash_types::BlockHash;
use bitcoin::hashes::hex::ToHex;
use std::sync::Mutex;
use serde_json;
use std::convert::TryFrom;
@ -39,6 +41,7 @@ impl Error for RpcError {}
pub struct RpcClient {
basic_auth: String,
endpoint: HttpEndpoint,
client: Mutex<Option<HttpClient>>,
id: AtomicUsize,
}
@ -50,6 +53,7 @@ impl RpcClient {
Ok(Self {
basic_auth: "Basic ".to_string() + credentials,
endpoint,
client: Mutex::new(None),
id: AtomicUsize::new(0),
})
}
@ -68,8 +72,12 @@ impl RpcClient {
"id": &self.id.fetch_add(1, Ordering::AcqRel).to_string()
});
let mut client = HttpClient::connect(&self.endpoint)?;
let mut response = match client.post::<JsonResponse>(&uri, &host, &self.basic_auth, content).await {
let mut client = if let Some(client) = self.client.lock().unwrap().take() { client }
else { HttpClient::connect(&self.endpoint)? };
let http_response = client.post::<JsonResponse>(&uri, &host, &self.basic_auth, content).await;
*self.client.lock().unwrap() = Some(client);
let mut response = match http_response {
Ok(JsonResponse(response)) => response,
Err(e) if e.kind() == std::io::ErrorKind::Other => {
match e.get_ref().unwrap().downcast_ref::<HttpError>() {