Bug 1877201 - Fix for a wrong comment_id returned after POST to bug/{bug_id}/comment

[ksy36]

I came across an issue where after posting comments to bug/{bug_id}/comment, the endpoint returns wrong comment id.

For example, for https://bugzilla.mozilla.org/show_bug.cgi?id=2068734, it returned 4120899, 4120900, 4120901 for the last 3 comments, while the actual ids are 18336000, 18336001 and 18336002.

It's currently passing comment_id to bz_last_key to get the id of just inserted comment

my $new_comment_id = $dbh->bz_last_key('longdescs', 'comment_id');

https://github.com/mozilla/bmo/blob/master/Bugzilla/WebService/Bug.pm#L1332-L1342

but on MySQL these parameters appears to be unused, it just selects last inserted id, which in this case is not a comment id, but auto incremented id from another table

sub bz_last_key {
  my ($self) = @_;

  my ($last_insert_id) = $self->selectrow_array('SELECT LAST_INSERT_ID()');

  return $last_insert_id;
}

https://github.com/mozilla/bmo/blob/master/Bugzilla/DB/Mysql.pm#L95-L101

I couldn't reproduce this locally though, so it might be something that's happening only on production.

[ksy36]

@dklawren, could you please r?

[Copilot]

🟢 Approval recommended

The focused implementation avoids unrelated auto-increment values and includes appropriate regression coverage.

Pull request overview

Fixes REST comment creation to return the inserted comment’s actual ID.

Changes:

• Uses the created comment object’s ID instead of connection-wide LAST_INSERT_ID().
• Adds regression coverage validating the returned ID.

File summaries

File	Description
Bugzilla/WebService/Bug.pm	Returns the inserted comment object’s ID.
qa/t/rest_bug_add_comment.t	Verifies the response references the newest comment.

Review details

• Files reviewed: 2/2 changed files
• Comments generated: 0
• Review effort level: Balanced

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[dklawren]

LGTM r=dkl