fluencelabs/redis
1
0
Fork 0
mirror of https://github.com/fluencelabs/redis synced 2025-06-21 13:01:32 +00:00
Code Issues Projects Releases Wiki Activity

Merge pull request #6703 from guybe7/blocking_xread_empty_reply

Browse Source 
Blocking XREAD[GROUP] should always reply with valid data (or timeout)
This commit is contained in:
Salvatore Sanfilippo
2020-01-09 17:32:14 +01:00
committed by GitHub
parent 64ef0ad71a a351e74fe9
commit bb93686754
3 changed files with 44 additions and 10 deletions
Download Patch File Download Diff File Expand all files Collapse all files

29
src/t_stream.c
View File

@ -797,6 +797,16 @@ int streamDeleteItem(stream *s, streamID *id) {
return deleted;
}
/* Get the last valid (non-tombstone) streamID of 's'. */
void streamLastValidID(stream *s, streamID *maxid)
{
streamIterator si;
streamIteratorStart(&si,s,NULL,NULL,1);
int64_t numfields;
streamIteratorGetID(&si,maxid,&numfields);
streamIteratorStop(&si);
}
/* Emit a reply in the client output buffer by formatting a Stream ID
* in the standard <ms>-<seq> format, using the simple string protocol
* of REPL. */
@ -1506,20 +1516,23 @@ void xreadCommand(client *c) {
{
serve_synchronously = 1;
serve_history = 1;
} else {
} else if (s->length) {
/* We also want to serve a consumer in a consumer group
* synchronously in case the group top item delivered is smaller
* than what the stream has inside. */
streamID *last = &groups[i]->last_id;
if (s->length && (streamCompareID(&s->last_id, last) > 0)) {
streamID maxid, *last = &groups[i]->last_id;
streamLastValidID(s, &maxid);
if (streamCompareID(&maxid, last) > 0) {
serve_synchronously = 1;
*gt = *last;
}
}
} else {
} else if (s->length) {
/* For consumers without a group, we serve synchronously if we can
* actually provide at least one item from the stream. */
if (s->length && (streamCompareID(&s->last_id, gt) > 0)) {
streamID maxid;
streamLastValidID(s, &maxid);
if (streamCompareID(&maxid, gt) > 0) {
serve_synchronously = 1;
}
}
@ -1871,11 +1884,7 @@ void xsetidCommand(client *c) {
* item, otherwise the fundamental ID monotonicity assumption is violated. */
if (s->length > 0) {
streamID maxid;
streamIterator si;
streamIteratorStart(&si,s,NULL,NULL,1);
int64_t numfields;
streamIteratorGetID(&si,&maxid,&numfields);
streamIteratorStop(&si);
streamLastValidID(s,&maxid);
if (streamCompareID(&id,&maxid) < 0) {
addReplyError(c,"The ID specified in XSETID is smaller than the "