Single file retrieval from PR uses outdated Bitbucket API

Your checklist for this issue

• [x ] Jenkins version

• [ x] Plugin version

• Bitbucket cloud

• [ x] Bitbucket server and version

Description

Jenkins version: 2.235.3 Plugin version: 2.9.1 Bitbucket server and version: 7.4.0

When the plugin needs to retrieve a single file from a pull-request in Bitbucket server it uses the at=pull-request reference which doesn’t seem to be supported post Bitbucket 7+.

Example snippet that triggers this behaviour

pipeline {

    agent {
        kubernetes {
            customWorkspace 'myworkspace'
            label 'mylabel'
            yamlFile 'Jenkinsfile.yml'
            defaultContainer 'java'
        }
    }

    stages {
        stage("Build") {
            steps {
	      sh "echo 'hello'"
            }
        }
    }
}

(line 7 with yamlFile being the culprit)

Stacktrace:

java.io.FileNotFoundException: URL: /rest/api/1.0/projects/test/repos/my-repro/browse/Jenkinsfile.yml?at=pull-requests%2F14%2Fmerge&start=0&limit=500
	at com.cloudbees.jenkins.plugins.bitbucket.server.client.BitbucketServerAPIClient.getRequest(BitbucketServerAPIClient.java:854)
	at com.cloudbees.jenkins.plugins.bitbucket.server.client.BitbucketServerAPIClient.getFileContent(BitbucketServerAPIClient.java:1149)
	at com.cloudbees.jenkins.plugins.bitbucket.filesystem.BitbucketSCMFile.content(BitbucketSCMFile.java:98)
	at jenkins.scm.api.SCMFile.contentAsString(SCMFile.java:335)

This is related to issue #294 where a similar issue was fixed, but this feels like a case that was left behind.

[xabolcs]

@bitwiseman enabling “Call changes API” doesn’t help for my Bitbucket Server 7 endpoint. But manually changing merge to from in the URL (/rest/api/1.0/projects/test/repos/my-repro/browse/Jenkinsfile.yml?at=pull-requests%2F14%2Ffrom&start=0&limit=500) helps.

Sure, enabling “Call changes API” helps for other areas in the Jenkins - Bitbucket Server integration, but not for lightweight checkout.

But the problem is the same - git ls-remote shows there is no more merge for newer PRs:

c5fe5646515e58eb67958cbb181ad301649fea97	refs/pull-requests/1422/from
69df8d813c2d96d0adee7103793d9b82951886fd	refs/pull-requests/1422/merge
c5fe5646515e58eb67958cbb181ad301649fea97	refs/pull-requests/1423/from
ad4b79b5f0809a802902df865a46e378fa04f0a4	refs/pull-requests/1423/merge
cf34c974f84a8e82886de42c82be97671e5777a5	refs/pull-requests/1685/from
d8d5f5fed6bf59a6cf406ad07b31fdb187f4b340	refs/pull-requests/2529/from
39613491f3aa82e6b2d15f7e3ffce5d57fc49fb6	refs/pull-requests/2781/from
05d9a108d265886b0737cd5b9815cea43828978f	refs/pull-requests/2802/from
9e70491d7b649c5aedd921b8aecbca50c82872ba	refs/pull-requests/2803/from
f791077eed5b19c03a7567023480467a88f2ec6e	refs/pull-requests/2804/from

---

Of course, using ChangeRequestCheckoutStrategy.HEAD works around the problem

[bitwiseman]

@xabolcs We’d welcome a PR that improves matters.