Fetch cancellation #19274
+98
−31
Fetch cancellation: Listen for cancellation and prematurely abort if …
…cancelled
- Loading branch information
commit 7249fd6bd82b70fa097ce2c66dc8bdb4bf023da8
| @@ -1087,6 +1087,7 @@ fn http_network_fetch(request: &Request, | ||
| let devtools_sender = context.devtools_chan.clone(); | ||
| let meta_status = meta.status.clone(); | ||
| let meta_headers = meta.headers.clone(); | ||
| let cancellation_listener = context.cancellation_listener.clone(); | ||
| thread::Builder::new().name(format!("fetch worker thread")).spawn(move || { | ||
| match StreamedResponse::from_http_response(res) { | ||
| Ok(mut res) => { | ||
| @@ -1109,6 +1110,11 @@ fn http_network_fetch(request: &Request, | ||
| } | ||
|
|
||
| loop { | ||
| if cancellation_listener.lock().unwrap().cancelled() { | ||
| *res_body.lock().unwrap() = ResponseBody::Done(vec![]); | ||
|
||
| let _ = done_sender.send(Data::Done); | ||
| return; | ||
| } | ||
| match read_block(&mut res) { | ||
| Ok(Data::Payload(chunk)) => { | ||
| if let ResponseBody::Receiving(ref mut body) = *res_body.lock().unwrap() { | ||
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In the context of #18676 I think that at this point the response would have been cached already, and such a cancellation would result in any subsequent request for the same url getting the empty cancelled response from the cache.
One way to solve this would be for the cache to disregard any cached responses that would have been cancelled. Checking for an empty response body might be one way to do so, perhaps a clearer way would be to use
ResponseBody::Emptyhere instead, or even introduce a newResponseBody::Cancelled?