If the request isn't complete, this endpoint will now submit the request and
wait for completion using the new API. This may still be susceptible to
timeouts for larger repos, but other endpoints now exist that the web
interface will use to negotiate its way through larger archive processes.
This API will *not* allow consumers to subscribe to specific requests being
completed, just *any* request being completed. The caller is responsible for
determining if their request is satisfied and waiting again if needed.
Increase all timeouts to 10 seconds; these aren't hard-coded sleeps, so
there's no guarantee we'll actually take that long. If we need longer to
not have a false-positive, then so be it.
While here, various assert.{Not,}Equal arguments are flipped around so that
the wording in error output reflects reality, where the expected argument is
second and actual third.
We don't need to risk failure and use time.ParseDuration to get 2 *
time.Second.
else if isn't really necessary if the conditions are simple enough and lead
to the same result.
When archival was made async, the GET endpoint was only useful if a previous
POST had initiated the download. This commit restores the previous behavior,
to an extent; we'll now submit the archive request there and return a
"202 Accepted" to indicate that it's processing if we didn't manage to
complete the request within ~2 seconds of submission.
This lets a client directly GET the archive, and gives them some indication
that they may attempt to GET it again at a later time.
Things got shuffled around such that we carefully build up and release
requests from the queue, so we can validate the state of the queue at each
step. Fix some assertions that no longer hold true as fallout.
Once we've signaled a cond var, it may take some small amount of time for
the goroutines released to hit the spot we're wanting them to be at. Give
them an appropriate amount of time.
Locking/unlocking the queueMutex is allowed, but not required, for
Cond.Signal() and Cond.Broadcast(). The magic at play here is just a little
too much for golangci-lint, as we take the address of queueMutex and this is
mostly used in archiver.go; the variable still gets flagged as unused.
This introduces two sync.Cond pointers to the archiver package. If they're
non-nil when we go to process a request, we'll wait until signalled (at all)
to proceed. The tests will then create the sync.Cond so that it can signal
at-will and sanity-check the state of the queue at different phases.
The author believes that nil-checking these two sync.Cond pointers on every
archive processing will introduce minimal overhead with no impact on
maintainability.
Some, or perhaps even most, archives will not take all that long to archive.
The archive process starts as soon as the download button is initially
clicked, so in theory they could be done quite quickly. Drop the initial
delay down to three-quarters of a second to make it more responsive in the
common case of the archive being quickly created.
The prime benefit being sought here is for large archives to not
clog up the rendering process and cause unsightly proxy timeouts.
As a secondary benefit, archive-in-progress is moved out of the
way into a /tmp file so that new archival requests for the same
commit will not get fulfilled based on an archive that isn't yet
finished.
This asynchronous system is fairly primitive; request comes in, we'll
spawn off a new goroutine to handle it, then we'll mark it as done.
Status requests will see if the file exists in the final location,
and report the archival as done when it exists.
Fixes#11265