Rewrite limitConcurrency to fix error catching

Make sure that we only catch errors that are a result of
calling fn()
pull/21833/head
Luke Barnard 2018-05-01 18:01:25 +01:00
parent da1a5616eb
commit 71c1198d12
1 changed files with 22 additions and 22 deletions

View File

@ -48,30 +48,30 @@ function checkBacklog() {
// Limit the maximum number of ongoing promises returned by fn to LIMIT and // Limit the maximum number of ongoing promises returned by fn to LIMIT and
// use a FIFO queue to handle the backlog. // use a FIFO queue to handle the backlog.
function limitConcurrency(fn) { async function limitConcurrency(fn) {
return new Promise((resolve, reject) => { if (ongoingRequestCount >= LIMIT) {
const item = () => { // Enqueue this request for later execution
ongoingRequestCount++; await new Promise((resolve, reject) => {
resolve(); backlogQueue.push(resolve);
}; });
if (ongoingRequestCount >= LIMIT) { }
// Enqueue this request for later execution
backlogQueue.push(item); let result;
} else { let error;
item();
} ongoingRequestCount++;
}) try {
.then(fn) result = await fn();
.catch((err) => { } catch (err) {
error = err;
} finally {
ongoingRequestCount--; ongoingRequestCount--;
checkBacklog(); checkBacklog();
throw err; }
})
.then((result) => { if (error) throw error;
ongoingRequestCount--;
checkBacklog(); return result;
return result;
});
} }
/** /**