The cloudformation for event pattern generated by cdk contains 'detailType' while it should generate the key as 'detail-type'

Description of the bug: When i use Cdk the cloudformation template that is generated for the 'event pattern ’ in a CfnRule construct contains the key as ‘detailType’ rather than ‘detail-type’

Reproduction Steps

Use the following in a Cdk stack

const cbEventPattern :EventPattern ={

    source: [
        'aws.codebuild'
    ],
    detail: {
        'build-status': [
            'FAILED'
        ],
        'project-name':' some value'
    },      
    detailType: [
      'CodeBuild Build State Change'
  ],


}
  const codeBuildRule = new CfnRule(this, 'CodeBuildCloudWatchEventsRule', {
    description: 'Code Build cloudwatch events rule',
    eventPattern: cbEventPattern,
    name: '',
    state: 'ENABLED'
})

Error Log

Environment

• CLI Version : 1.20.0
• Framework Version:0.22
• OS :Windows
• Language :typescript

Other

I found the following link https://github.com/aws/aws-cdk/blob/master/packages/%40aws-cdk/aws-events/lib/rule.ts#L348 although i see a solve is there it does not work.

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This is 🐛 Bug Report

[rektide]

@rix0rrr the docs for https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_aws-events.CfnRule.html#eventpattern-1 are incredibly confusing:

Type: any

AWS::Events::Rule.EventPattern.

This is confusing but it gives the impression that it expects an EventPattern. The EventPattern docs helpfully clarify this is not the case, but the docs for CfnRule are quite confusing. EventPattern trying to correct the situation:

Important: this class can only be used with a Rule class. In particular, do not use it with CfnRule class: your pattern will not be rendered correctly. In a CfnRule class, write the pattern as you normally would when directly writing CloudFormation.

[enrico-usai]

I resolved this problem by passing a raw dictionary, rather than an EventPattern, given that event_pattern attribute can be Any:

     events.CfnRule(
            scope=self,
            id="xxx",
            event_pattern={
                "detail": {
                    "build-status": ["FAILED", "STOPPED", "SUCCEEDED"],
                    "project-name": [xxx],
                },
                "detail-type": ["CodeBuild Build State Change"],
                "source": ["aws.codebuild"],
            },
            state="ENABLED",
        )