Incorrect `$.detail.commitId` in codecommit EventBridge Rule using CDK

Question

I'm trying to send the `commitId` to my lambda function when someone created a tag with a certain prefix by setting up an event rule in a stack, the sending part is working but the `commitId` is incorrect and doesn't exist anywhere in the repo.

sample code below
```typescript
    const rule = new events.Rule(this, 'PipelineTrigger', {
      eventPattern: {
        source: ['aws.codecommit'],
        resources: [repo.repositoryArn],
        detailType: ['CodeCommit Repository State Change'],
        detail: {
          event: ['referenceCreated'],
          repositoryName: ['my-repo'],
          referenceType: ['tag'],
          referenceName: [
            {
              prefix: `release-`
            }
          ]
        }
      }
    });

rule.addTarget(
      new aws_events_targets.LambdaFunction(fn, {
        event: cdk.aws_events.RuleTargetInput.fromObject({
          commitId: events.EventField.fromPath('$.detail.commitId')
        })
      })
    );
```

I also checked the `$.detail.referenceName` and it has the correct git tag name.

where does the AWS get the `$.detail.commitId`? is it different from the `commitId` of the git tag?

Answer

To help you with your query, I created one similar EventBridge rule and target using the code you provided(with modifications to deploy it in my account).

Once the rule got created, I [created a commit](https://docs.aws.amazon.com/codecommit/latest/userguide/how-to-create-commit.html) into one of my CodeCommit repositories and then [created one git tag](https://docs.aws.amazon.com/codecommit/latest/userguide/how-to-create-tag.html)

I used below mentioned commands to create the git tag
```
$ git tag release-test cf488685
$ git push origin release-test
```

Here, cf488685 is the shorter version of the full commitId (cf488685bfd6f8d4f6def8e985a3648b18333d3e)

Once the git tag was created, I checked the lambda function logs and it received the commitId cf488685bfd6f8d4f6def8e985a3648b18333d3e. So, the configuration that you've used in CDK is correct. To be specific, here `$.detail.commitId` is the full commitId of the commitId that we used while creating git tag (if we specified shorter version). Therefore, please check if the commitId that you're noticing is the full version of the id that you specified while creating git tag.

If you have a support plan with your account, then you can reach out to us creating a support case from the [`Support Center`](https://docs.aws.amazon.com/awssupport/latest/user/case-management.html#creating-a-support-case) as well.

Incorrect `$.detail.commitId` in codecommit EventBridge Rule using CDK

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