Get the pull request ID of a continuous deployment release [Azure Pipelines] - azure

Question

I am trying to setup azure pipelines to trigger a build on every PR update, and a release on every merge. For a couple of reasons when the PR is merged, i need to access data saved by the latest validation build of the PR.
However to do that i need the PRid during the run of the Release pipeline. How can one achieve that?

Answer 1

From the release you can retrieve the commit Id which triggered the build.
Then you search for the commitId in the list of completed PRs and retrieve your PR number.
$commitId = "$(RELEASE.ARTIFACTS.{YOURARTIFACTALIAS}.SOURCEVERSION)"
$repoId = "$(RELEASE.ARTIFACTS.{YOURARTIFACTALIAS}.REPOSITORY.ID)"
$pullRequestsUri = "https://dev.azure.com/{organization}/{project}_apis/git/repositories/" + $repoId + "/pullrequests?searchCriteria.status=completed&api-version=5.1"
$base64AuthInfo = [Convert]::ToBase64String([Text.Encoding]::ASCII.GetBytes(("{0}:{1}" -f "", "$(System.AccessToken)")))
$pullRequests = Invoke-RestMethod -Uri $pullRequestsUri -Method GET -ContentType "application/json" -Headers #{Authorization = "Basic $base64AuthInfo" }
foreach ($value in $pullRequests.value) {
if ($value.lastMergeCommit.commitId -eq $commitId) {
$pullRequestId = $value.pullRequestId
}
}
Write-Host $pullRequestId

Answer 2

Based on your scenario, to my knowledge, it is complex to get related build information in your release. Besides, it may cause unexpected result if not cover all possible scenarios.
I'd suggest that you could refer to these steps blow:
Remove publish build/pipeline artifact or unnecessary tasks, just remain tasks for validation, which will save a lot of time. (Because, in general, the validation build will be triggered too many times, waste too much time to publish useless artifact or other data)
Create a new build pipeline and enable Continuous integration for target branch (e.g. master)
Add publish build/pipeline artifact task
Edit release pipeline and link this build pipeline and enable Continuous deployment. (Could add additional filters)
With this way, after completing the pull request, this new build pipeline will be triggered and will publish necessary artifact, then the release will be triggered.
For pull request validation builds, they just do tasks to validate the code (e.g. build project), but not publish artifact.
Simple scenario for saving time:
A pull request has 50 validation builds
old way: publish artifact of each takes 1 minutes, then total time is 50 minutes
new way: the new pipeline do tasks for build and publish, it just run once and may just takes 10 minutes.
Then you can save 40 minutes.

Answer 3

In Release Pipeline, you could use the variable $(RELEASE.ARTIFACTS.<<Source alias name>>.PULLREQUEST.ID) to get the Pull Request ID.
Note: the Source alias name is the name set in the release artifacts.
By the way, if you use a default variable in your script, you must first replace the . in the default variable names with _.
For example: $env:RELEASE_ARTIFACTS_<<Source alias name>>_PULLREQUEST_ID
Here is a doc about the Release variables.
Hope this helps.