silverorange
The PR above (#12), is that the new PR that you opened? Or is that the old PR?

PR #12 is a brand new PR opened for testing after updating the github branch source plugin.  I get the same error when I open any other new PR, until downgrading github branch source plugin to previous verison (2.4.5) 

Also just ran into this issue. Jenkins 2.164.2 running in a container inside GKE. Downgrading GitHub Branch Source from 2.5.0 down to 2.4.5 resolved the issue. It seems Jenkins is combining the PR commit with the master branch commit to produce a new commit, which does not exist at GitHub, but Jenkins is making an API call into GitHub for commit info, resulting in the error.

Caleb that is similar to what I'm seeing.  The commit referenced in the error does not exist as far as I can see, I cannot access it through the github api manually either.  The commit SHA does NOT match the commit SHA shown on the PR in github. 

calebd
Stack trace would be helpful. Also, is this occurring when scanning the PR or from github hook? Has the PR that is failing been around a while untouched or has it been opened/updated recently?

silverorange, calebd
The commit sha that 2.5.0 is looking for is the

that is valid. Could you please give that a try?

To be clear, there is still a bug here and I'm working on that, but I want to make sure my theory is correct so I'm fixing the right thing.

Liam, here are the steps I followed.  Hope this is helpful:

1. Updated github branch source plugin to 2.5.0 again
2. Closed PR #12 (same PR as mentioned in original post).  
3. Re-opened PR #12

In jenkins the closing of the PR spawned a CI check which failed with similar error as before. 

Pull request #12 closed

Connecting to https://api.github.com using xxxxxxxx/****** (xxxxxxxx Github Personal Access Token)

GitHub has been notified of this commit’s build result

java.io.FileNotFoundException: https://api.github.com/repos/xxxxxx/xxxxxxxxx/commits/xxxxxxxxxxxxdbe80d1e82bf97cb9e6ae867
at com.squareup.okhttp.internal.huc.HttpURLConnectionImpl.getInputStream(HttpURLConnectionImpl.java:243)
at com.squareup.okhttp.internal.huc.DelegatingHttpsURLConnection.getInputStream(DelegatingHttpsURLConnection.java:210)
at com.squareup.okhttp.internal.huc.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:25)
at org.kohsuke.github.Requester.parse(Requester.java:625)
at org.kohsuke.github.Requester.parse(Requester.java:607)
at org.kohsuke.github.Requester._to(Requester.java:285)

Caused: org.kohsuke.github.GHFileNotFoundException: {"message":"No commit found for SHA: xxxxxxxxxxxxc14dbe80d1e82bf97cb9e6ae867","documentation_url":"https://developer.github.com/v3/repos/commits/#get-a-single-commit"}
at org.kohsuke.github.Requester.handleApiError(Requester.java:699)
at org.kohsuke.github.Requester._to(Requester.java:306)
at org.kohsuke.github.Requester.to(Requester.java:247)
at org.kohsuke.github.GHRepository.getCommit(GHRepository.java:973)
at org.jenkinsci.plugins.github_branch_source.PullRequestSCMRevision.validateMergeHash(PullRequestSCMRevision.java:118)
at org.jenkinsci.plugins.github_branch_source.GitHubSCMFileSystem.<init>(GitHubSCMFileSystem.java:91)
at org.jenkinsci.plugins.github_branch_source.GitHubSCMFileSystem$BuilderImpl.build(GitHubSCMFileSystem.java:296)
at jenkins.scm.api.SCMFileSystem.of(SCMFileSystem.java:294)
at org.jenkinsci.plugins.workflow.multibranch.SCMBinder.create(SCMBinder.java:103)
at org.jenkinsci.plugins.workflow.job.WorkflowRun.run(WorkflowRun.java:293)
at hudson.model.ResourceController.execute(ResourceController.java:97)
at hudson.model.Executor.run(Executor.java:429)

Finished: FAILURE

The GitHub PR re-open process did not seem to spawn a new CI run so I added a new commit, the new commit spawned CI which also failed:

Pull request #12 updated

Connecting to https://api.github.com using xxxxxxxxxx/****** (xxxxx Github Personal Access Token)

GitHub has been notified of this commit’s build result

java.io.FileNotFoundException: https://api.github.com/repos/xxxxxxx/xxxxxxxxxxx/commits/xxxxxxxxxxxxc2b7cd41940bbc762409886a5e84ef
at com.squareup.okhttp.internal.huc.HttpURLConnectionImpl.getInputStream(HttpURLConnectionImpl.java:243)
at com.squareup.okhttp.internal.huc.DelegatingHttpsURLConnection.getInputStream(DelegatingHttpsURLConnection.java:210)
at com.squareup.okhttp.internal.huc.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:25)
at org.kohsuke.github.Requester.parse(Requester.java:625)
at org.kohsuke.github.Requester.parse(Requester.java:607)
at org.kohsuke.github.Requester._to(Requester.java:285)

Caused: org.kohsuke.github.GHFileNotFoundException: {"message":"No commit found for SHA: xxxxxxxxxxx7cd41940bbc762409886a5e84ef","documentation_url":"https://developer.github.com/v3/repos/commits/#get-a-single-commit"}
at org.kohsuke.github.Requester.handleApiError(Requester.java:699)
at org.kohsuke.github.Requester._to(Requester.java:306)
at org.kohsuke.github.Requester.to(Requester.java:247)
at org.kohsuke.github.GHRepository.getCommit(GHRepository.java:973)
at org.jenkinsci.plugins.github_branch_source.PullRequestSCMRevision.validateMergeHash(PullRequestSCMRevision.java:118)
at org.jenkinsci.plugins.github_branch_source.GitHubSCMFileSystem.<init>(GitHubSCMFileSystem.java:91)
at org.jenkinsci.plugins.github_branch_source.GitHubSCMFileSystem$BuilderImpl.build(GitHubSCMFileSystem.java:296)
at jenkins.scm.api.SCMFileSystem.of(SCMFileSystem.java:294)
at org.jenkinsci.plugins.workflow.multibranch.SCMBinder.create(SCMBinder.java:103)
at org.jenkinsci.plugins.workflow.job.WorkflowRun.run(WorkflowRun.java:293)
at hudson.model.ResourceController.execute(ResourceController.java:97)
at hudson.model.Executor.run(Executor.java:429)

Finished: FAILURE

In my case, the pull request that I first noticed with this issue existed before updating to 2.5.0. Before 2.5.0 the pipeline timed out while waiting for an approval.

After upgrading to 2.5.0 the PR couldn't be built because it immediately failed on the first attempt to interact with GitHub. Builds failed regardless of how the build was triggered, via GitHub webhook or as a rerun inside Jenkins.

I also made a brand new PR with different commits and it failed the same way, both via webhook and rerun attempts.

Here is a stacktrace with some of the details made private:

Pull request #1 updated
14:14:01 Connecting to https://api.github.com using xxxxxx/******

GitHub has been notified of this commit’s build result

java.io.FileNotFoundException: https://api.github.com/repos/xxxxxx/xxxxxx/commits/xxxxxxxxxxxxxxxxxxxxabec08e96270c1de09bb
	at com.squareup.okhttp.internal.huc.HttpURLConnectionImpl.getInputStream(HttpURLConnectionImpl.java:243)
	at com.squareup.okhttp.internal.huc.DelegatingHttpsURLConnection.getInputStream(DelegatingHttpsURLConnection.java:210)
	at com.squareup.okhttp.internal.huc.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:25)
	at org.kohsuke.github.Requester.parse(Requester.java:625)
	at org.kohsuke.github.Requester.parse(Requester.java:607)
	at org.kohsuke.github.Requester._to(Requester.java:285)
Caused: org.kohsuke.github.GHFileNotFoundException: {"message":"No commit found for SHA: xxxxxxxxxxxxxxxxxxxxabec08e96270c1de09bb","documentation_url":"https://developer.github.com/v3/repos/commits/#get-a-single-commit"}
	at org.kohsuke.github.Requester.handleApiError(Requester.java:699)
	at org.kohsuke.github.Requester._to(Requester.java:306)
	at org.kohsuke.github.Requester.to(Requester.java:247)
	at org.kohsuke.github.GHRepository.getCommit(GHRepository.java:973)
	at org.jenkinsci.plugins.github_branch_source.PullRequestSCMRevision.validateMergeHash(PullRequestSCMRevision.java:118)
	at org.jenkinsci.plugins.github_branch_source.GitHubSCMFileSystem.<init>(GitHubSCMFileSystem.java:91)
	at org.jenkinsci.plugins.github_branch_source.GitHubSCMFileSystem$BuilderImpl.build(GitHubSCMFileSystem.java:296)
	at jenkins.scm.api.SCMFileSystem.of(SCMFileSystem.java:294)
	at org.jenkinsci.plugins.workflow.multibranch.SCMBinder.create(SCMBinder.java:103)
	at org.jenkinsci.plugins.workflow.job.WorkflowRun.run(WorkflowRun.java:293)
	at hudson.model.ResourceController.execute(ResourceController.java:97)
	at hudson.model.Executor.run(Executor.java:429)
Finished: FAILURE

From the pull request event log:

Changes detected: PR-1 (xxxxxxxxxxxxxxxxxxxx723d39265d8c2206c7f9+xxxxxxxxxxxxxxxxxxxxe1ca98cf39f9c2c75b54 (UNKNOWN_MERGE_STATE) → xxxxxxxxxxxxxxxxxxxx0b218e1baa39a7af38ca+xxxxxxxxxxxxxxxxxxxxe1ca98cf39f9c2c75b54 (xxxxxxxxxxxxxxxxxxxxabec08e96270c1de09bb))
Scheduled build for branch: PR-1

Where xxxxxxxxxxxxxxxxxxxxe1ca98cf39f9c2c75b54 is the master branch commit.

The commit xxxxxxxxxxxxxxxxxxxxabec08e96270c1de09bb exists as part of the org but not the PR author's repo fork.

So to add a little more information here.   Forgive me, I'm not an expert on this subject.  Jenkins is looking for the SHA on the GitHub user the repo was forked by (in which the commits were pushed from).  I.e. https://api.github.com/repos/MY-GITHUB-USER

If I query the github API for htps://api.github.com/repos/MY-GITHUB-USER/MY-REPO/pulls I get nothing returned (because there are no PRs under my fork). 

If I query the user (our org's github username) in which the commits were pushed to I get results returned.

Could this issue be related to how the PR is opened from a user's fork? 

I get info about the commit SHA if I query:

api.github.com/repos/MY-ORGS-GITHUB-ACCOUNT/xxxxxx/commits/xxxxxx7cd41940bbc762409886a5e84ef

but not if I query my user account in which the PR was opened from:

api.github.com/repos/MY-GITHUB-USER/xxxxx/commits/xxxxxxxx7cd41940bbc762409886a5e84ef