Hanging when creating a pull request (due allegedly to a huge repository)

[typeless]

• Gitea version (or commit ref):
  https://github.com/gogits/gogs/commit/8ee14db51ebc92728e1edba4545c7d4ea4b21c65
  This is exactly the Gogs release version 0.9.97.0901

• Git version:
  git version 2.7.4

• Operating system:
  `Ubuntu Server 16.04

• Database (use [x]):

  • PostgreSQL
  • MySQL
  • SQLite

• Log gist:

31630 Nov 25 16:37:37 DIR-101 gogs[32041]: [Macaron] 2016-11-25 16:37:37: Started POST /test/BCM-Android-Linux-Test/compare/master...mura:master for 192.168.222.65
31631 Nov 25 16:37:37 DIR-101 gogs[32041]: 2016/11/25 16:37:37 [D] Session ID: f64a95bdfc4e1143
31632 Nov 25 16:37:37 DIR-101 gogs[32041]: 2016/11/25 16:37:37 [D] CSRF Token: cl6PKtu_cFKSebHPtlJdAv0Y9-k6MTQ4MDA1OTY5NjgzOTI2NTkzMA==
31633 Nov 25 16:37:37 DIR-101 gogs[32041]: 2016/11/25 16:37:37 [T] PullRequest[0].testPatch (patchPath): /home/git/gogs-repositories/test/bcm-android-linux-test.git/pulls/1.patch
31634 Nov 25 16:41:38 DIR-101 gogs[32041]: 2016/11/25 16:41:38 [T] PushToBaseRepo[37]: pushing commits to base repo 'refs/pull/1/head'
31635 Nov 25 16:41:38 DIR-101 gogs[32041]: 2016/11/25 16:41:38 [T] DeliverHooks [repo_id: 37]
31636 Nov 25 16:41:39 DIR-101 gogs[32041]: 2016/11/25 16:41:39 [T] Pull request created: 37/19
31637 Nov 25 16:41:39 DIR-101 gogs[32041]: [Macaron] 2016-11-25 16:41:39: Completed /test/BCM-Android-Linux-Test/compare/master...mura:master 302 Found in 4m1.573187867s
31638 Nov 25 16:41:39 DIR-101 gogs[32041]: [Macaron] 2016-11-25 16:41:39: Started GET /test/BCM-Android-Linux-Test/pulls/1 for 192.168.222.65
31639 Nov 25 16:41:39 DIR-101 gogs[32041]: 2016/11/25 16:41:39 [D] Session ID: f64a95bdfc4e1143
31640 Nov 25 16:41:39 DIR-101 gogs[32041]: 2016/11/25 16:41:39 [D] CSRF Token: cl6PKtu_cFKSebHPtlJdAv0Y9-k6MTQ4MDA1OTY5NjgzOTI2NTkzMA==
31641 Nov 25 16:41:39 DIR-101 gogs[32041]: 2016/11/25 16:41:39 [D] Template: repo/issue/view
31642 Nov 25 16:41:39 DIR-101 gogs[32041]: [Macaron] 2016-11-25 16:41:39: Completed /test/BCM-Android-Linux-Test/pulls/1 200 OK in 266.321449ms

Description

If I am not misinterpreting the log, it took around 4 minutes to reply the POST of the PR creation.
...

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[tboerger]

Since you are posting this issue to Gitea, have you also tried the same with Gitea master? Just to confirm this is a remaining issue.

[typeless]

@tboerger Since the log was captured on a production server which is not entirely controlled by me, it's a bit of risky to upgrade and test the setup right now. I am trying to come up with a way to make it easier to be reproduced (and test it with latest Gitea).

[typeless]

The alleged culprit https://github.com/go-gitea/gitea/blob/master/models/pull.go#L342, according to the log.

[tboerger]

I will mark it as a bug for now, but please try to provide more feedback on this.

[typeless]

@tboerger Confirmed. The latest Gitea exhibits the same behavior.

[typeless]

testPatch()
  UpdateLocalCopyBranch(branch string)
    UpdateLocalCopyBranch(repoPath, localPath, branch string)
        // Clone, Checkout, or Pull

The above is the relevant call trace for creating a PR.

The method testPatch is responsible for reporting the status of the PR. (PullRequestStatusConflict, PullRequestStatusChecking or PullRequestStatusMergeable)

The problem here is that Gogs/Gitea will try to clone or checkout the entire repository just for checking if there is any conflict. FWIW, the cloned repository will be stored at data/tmp.

[strk]

It looks like `git apply` supports `--check` to only check w/out applying. This should remove the need to clone the repository.

[typeless]

git read-tree --index-output=${INDEX_TMP_FILE} ${BRANCH_NAME}
GIT_INDEX_FILE=${INDEX_TMP_FILE} git apply --check --cached ${PATCH_FILE}

The above seems to be a viable approach to test patches with solely bare repository. I have tested on my laptop with a much simplified Gitea setup.