CloudFormation, apply Condition on DependsOn

Question

The task that I need to do is make CDN depend on a S3 bucket. But we want to make it use the existing bucket rather than creating a new one.

Here is the sample code

Answer 1

For yaml users, you can also use:

Conditions:
  CreateConfigRecorder: !Equals [ !Ref ConfigRecorderExists, 'false' ]

Resource:
#my 1st AWS Resource
  ConfigRecorder: 
    Condition: CreateConfigRecorder
    Type: AWS::Config::ConfigurationRecorder
    *more codes below*

#added, since DependsOn: !If is not possible, trigger by WaitCondition if CreateConfigRecorder is true
#Hacks: https://garbe.io/blog/2017/07/17/cloudformation-hacks/
  ConfigRecorderWaitHandle: 
    Condition: CreateConfigRecorder
    DependsOn: ConfigRecorder
    Type: "AWS::CloudFormation::WaitConditionHandle"
#added, since DependsOn: !If is not possible, trigger by WaitCondition if CreateConfigRecorder is false
  WaitHandle: 
    Type: "AWS::CloudFormation::WaitConditionHandle"
#added, since DependsOn: !If is not possible
  WaitCondition: 
    Type: "AWS::CloudFormation::WaitCondition"
    Properties: 
      Handle: !If [CreateConfigRecorder, !Ref ConfigRecorderWaitHandle, !Ref WaitHandle]
      Timeout: "1"
      Count: 0
#my 2nd AWS Resource that requires DependsOn Attribute
  AWSConfigRule:
    Type: AWS::Config::ConfigRule
    DependsOn: WaitCondition #added, since DependsOn: !If is not possible
    *more codes below*

Basically my 2nd resource only has DependsOn attribute if my 1st resource is non-existent, before running the CFN. I got this from: https://garbe.io/blog/2017/07/17/cloudformation-hacks/