FIS: Experiment Template Log Configuration Class Camel Cases LogGroupArn

[hakenmt]

Describe the bug

Using the CfnExperimentTemplate construct in .net. Using the below log group configuration.

LogConfiguration = new ExperimentTemplateLogConfigurationProperty() {
                    CloudWatchLogsConfiguration = new CloudWatchLogsConfigurationProperty() {
                        LogGroupArn = this.LogGroup.LogGroupArn
                    }
                }

This produces output like the following:

"LogConfiguration": {
     "CloudWatchLogsConfiguration": {
      "logGroupArn": {
       "Fn::GetAtt": [
        "logGroup68A52FBE",
        "Arn"
       ]
      }
     },
     "LogSchemaVersion": 0
    },

The property logGroupArn isn't accepted by CloudFormation, it must be LogGroupArn.

Expected Behavior

Produces this output:

"LogConfiguration": {
     "CloudWatchLogsConfiguration": {
      "LogGroupArn": {
       "Fn::GetAtt": [
        "logGroup68A52FBE",
        "Arn"
       ]
      }
     },
     "LogSchemaVersion": 0
    },

Current Behavior

Produces camel case name.

Reproduction Steps

LogConfiguration = new ExperimentTemplateLogConfigurationProperty() {
                    CloudWatchLogsConfiguration = new CloudWatchLogsConfigurationProperty() {
                        LogGroupArn = this.LogGroup.LogGroupArn
                    }
                }

Possible Solution

No response

Additional Information/Context

No response

CDK CLI Version

2.133.0 (build dcc1e75)

Framework Version

No response

Node.js Version

v20.9.0

OS

darwin

Language

.NET

Language Version

No response

Other information

No response

[nmussy]

Confirmed in TypeScript and with v2.136.0. See also the AWS::FIS::ExperimentTemplate CloudWatchLogsConfiguration CloudFormation docs

import { CfnExperimentTemplate } from 'aws-cdk-lib/aws-fis';

// ...
new CfnExperimentTemplate(this, "ExperimentTemplate", {
  description: "description",
  roleArn: "roleArn",
  logConfiguration: {
    cloudWatchLogsConfiguration: {
      logGroupArn: "logArn",
    } satisfies CfnExperimentTemplate.CloudWatchLogsConfigurationProperty,
    logSchemaVersion: 0,
  },
  stopConditions: [
    {
      source: "aws:cloudwatch:alarm",
      value: "alarmArn",
    },
  ],
  targets: {
    name: {
      resourceType: "aws:ec2:instance",
      resourceArns: ["resourceArn"],
      selectionMode: "64",
    },
  },
});

$ npm run cdk synth

Resources:
  ExperimentTemplate:
    Type: AWS::FIS::ExperimentTemplate
    Properties:
      Description: description
      LogConfiguration:
        CloudWatchLogsConfiguration:
          logGroupArn: logArn
        LogSchemaVersion: 0
      RoleArn: roleArn
      StopConditions:
        - Source: aws:cloudwatch:alarm
          Value: alarmArn
      Targets:
        name:
          ResourceArns:
            - resourceArn
          ResourceType: aws:ec2:instance
          SelectionMode: "64"

EDIT: Updated the repro, previous example didn't prove anything

[nmussy]

Not sure how the L1 generated constructs handle this, but I'm going to assume that this is happening because the cloudWatchLogsConfiguration property is not properly typed, see docs. Because it's just any object, I think that the CDK will not translate the property key because it does not expect it to be a CloudFormation object.

I'm not great in C# @hakenmt, but what you can do in the meantime is just not type the cloudWatchLogsConfiguration value, something like this:

LogConfiguration = new ExperimentTemplateLogConfigurationProperty() {
    CloudWatchLogsConfiguration = new {
        LogGroupArn = this.LogGroup.LogGroupArn
    }
}

[hakenmt]

Thanks for the workaround, I actually ended up doing this:

this.PacketLossExperiment.AddOverride("Properties.LogConfiguration.CloudWatchLogsConfiguration.LogGroupArn", this.LogGroup.LogGroupArn);
this.PacketLossExperiment.AddOverride("Properties.LogConfiguration.CloudWatchLogsConfiguration.logGroupArn", null);

I think both work, but obviously ideally would like to use the concrete generated type for the property if possible. The entire ExperimentTemplate construct is fairly hard to navigate, the Action and Target properties are both just object? objects (like any), instead of being something like Dictionary<string, ExperimentTemplateTargetProperty>.

[nmussy]

Yeah, your solution at least keeps some type safety 👍

As far as the issues with the generated L1, I don't have a ton of insight into that process. There was an issue raised about creating an L2 construct for ExperimentTemplate (#13744), but it never got a PR

[khushail]

Hi @hakenmt , thanks for reaching out with this bug info.
Thanks @nmussy for sharing the repro code in Typescript. I also see the casing issue in generated synth output template.
Marking this issue as appropriate. Also Please feel free to submit a PR for L2 construct if you are willing.

[pahud]

This property is typed any so we need to provide a JSON-like structure for it.
https://docs.aws.amazon.com/cdk/api/v2/docs/aws-cdk-lib.aws_fis.CfnExperimentTemplate.ExperimentTemplateLogConfigurationProperty.html#cloudwatchlogsconfiguration

related to #21767

[nmussy]

@pahud From what I gather, https://github.com/cdklabs/awscdk-service-spec needs to get a patch PR to override the currently generated L1?

[pahud]

@nmussy No, from my take, it's because it’s originally set to Json in cfnspec but at some point was added to an actual type by service team. To avoid breaking changes in CDK, we added a patch from awscdk-service-spec to make it always JSON type even it’s now typed in CFN. We have some other similar cases mentioned in #21767

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