substitution variable $BRANCH_NAME gives nothing while building - google-cloud-platform

Question

I'm building docker images using cloud builder trigger, previously $BRNACH_NAME was working but now its giving null.
Thanks in advance.

Answer 1

I will post my comment as an answer as it is too long for comment section.
According to this documentation, you should have the possibility to use $BRANCH_NAME default substitution for builds invoked by triggers.
In the same documentation it is stated that:
If a default substitution is not available (such as with sourceless
builds, or with builds that use storage source), then occurrences of
the missing variable are replaced with an empty string.
I assume this might be the reason you are receiving NULL.
Have you performed any changes? Could you please provide some further information, such as your .yaml/.json file, your trigger configuration and the error you are receiving?

Answer 2

The problem was not in $BRANCH_NAME, I was using the resulted JSON to fetch the branch name.
like,
"source": {
"repoSource": {
"projectId": "project_id",
"repoName": "bitbucket_repo_name",
"branchName": "integration"
}
}
and
I was using build_details['source']['repoSource']['branchName']
but now it's giving like
"source": {
"repoSource": {
"projectId": "project_id",
"repoName": "bitbucket_repo_name",
"commitSha": "ght8939jj5jd9jfjfjigk0949jh8wh4w"
}
},
so, now I'm using build_details['substitutions']['BRANCH_NAME'] and its working fine.