Go: object type not recognized

[njlynch]

🐛 Bug Report

Affected Languages

• Go

General Information

• JSII Version: 1.30.0 (build adae23f), typescript 3.9.9
• Platform: OSX (Darwin Kernel Version 19.6.0)

What is the problem?

See aws/aws-cdk#15007.

Attempting to create a CfnFunction_FunctionConfigProperty results in a malformed object that doesn't pass required field checks.

The following should work, but complains that the comment and runtime properties aren't set:

	awscloudfront.NewCfnFunction(stack, jsii.String("myCDKFunction"), &awscloudfront.CfnFunctionProps{
		Name:         jsii.String("myCfnFunctionCdk"),
		FunctionCode: jsii.String(myFunctionCode),
		AutoPublish:  jsii.Bool(true),
		FunctionConfig: &awscloudfront.CfnFunction_FunctionConfigProperty{
			Comment: jsii.String("testcdk"),
			Runtime: jsii.String("cloudfront-js-1.0"),
		},
	})

Verbose Log

JSII_DEBUG output

>{"api":"load","name":"constructs","version":"10.0.5","tarball":"/var/folders/cf/ttmfqtv97z13mfktyqcjgq040000gr/T/constructs-1.30.0.521499037.tgz"}
[@jsii/kernel] load {
  api: 'load',
  name: 'constructs',
  version: '10.0.5',
  tarball: '/var/folders/cf/ttmfqtv97z13mfktyqcjgq040000gr/T/constructs-1.30.0.521499037.tgz'
}
[@jsii/kernel] creating jsii-kernel modules workdir: /var/folders/cf/ttmfqtv97z13mfktyqcjgq040000gr/T/jsii-kernel-XdEwkS
< {"ok":{"assembly":"constructs","types":10}}
> {"api":"load","name":"aws-cdk-lib","version":"2.0.0-rc.7","tarball":"/var/folders/cf/ttmfqtv97z13mfktyqcjgq040000gr/T/aws-cdk-lib-1.30.0.948206680.tgz"}
[@jsii/kernel] load {
  api: 'load',
  name: 'aws-cdk-lib',
  version: '2.0.0-rc.7',
  tarball: '/var/folders/cf/ttmfqtv97z13mfktyqcjgq040000gr/T/aws-cdk-lib-1.30.0.948206680.tgz'
}
< {"ok":{"assembly":"aws-cdk-lib","types":6514}}
> {"api":"create","fqn":"aws-cdk-lib.App","args":[null]}
[@jsii/kernel] create { api: 'create', fqn: 'aws-cdk-lib.App', args: [ null ] }
[@jsii/kernel] toSandbox null [{"serializationClass":"Struct","typeRef":{"docs":{"summary":"initialization properties."},"name":"props","optional":true,"type":{"fqn":"aws-cdk-lib.AppProps"}}}]
< {"ok":{"$jsii.byref":"aws-cdk-lib.App@10000"}}
> {"api":"create","fqn":"aws-cdk-lib.Stack","args":[{"$jsii.byref":"aws-cdk-lib.App@10000"},"GocloudfrontStack",{"$jsii.struct":{"fqn":"aws-cdk-lib.StackProps","data":{}}}]}
[@jsii/kernel] create {
  api: 'create',
  fqn: 'aws-cdk-lib.Stack',
  args: [
    { '$jsii.byref': 'aws-cdk-lib.App@10000' },
    'GocloudfrontStack',
    { '$jsii.struct': [Object] }
  ]
}
[@jsii/kernel] toSandbox { '$jsii.byref': 'aws-cdk-lib.App@10000' } [{"serializationClass":"RefType","typeRef":{"docs":{"summary":"Parent of this stack, usually an `App` or a `Stage`, but could be any construct."},"name":"scope","optional":true,"type":{"fqn":"constructs.Construct"}}}]
[@jsii/kernel] toSandbox GocloudfrontStack [{"serializationClass":"Scalar","typeRef":{"docs":{"remarks":"If `stackName` is not explicitly\ndefined, this id (and any parent IDs) will be used to determine the\nphysical ID of the stack.","summary":"The construct ID of this stack."},"name":"id","optional":true,"type":{"primitive":"string"}}}]
[@jsii/kernel] toSandbox { '$jsii.struct': { fqn: 'aws-cdk-lib.StackProps', data: {} } } [{"serializationClass":"Struct","typeRef":{"docs":{"summary":"Stack properties."},"name":"props","optional":true,"type":{"fqn":"aws-cdk-lib.StackProps"}}}]
< {"ok":{"$jsii.byref":"aws-cdk-lib.Stack@10001"}}
> {"api":"create","fqn":"Object"}
[@jsii/kernel] create { api: 'create', fqn: 'Object' }
< {"ok":{"$jsii.byref":"Object@10002"}}
> {"api":"create","fqn":"aws-cdk-lib.aws_cloudfront.CfnFunction","args":[{"$jsii.byref":"aws-cdk-lib.Stack@10001"},"myCDKFunction",{"$jsii.struct":{"fqn":"aws-cdk-lib.aws_cloudfront.CfnFunctionProps","data":{"autoPublish":true,"functionCode":"hi","functionConfig":{"$jsii.byref":"Object@10002"},"name":"myCfnFunctionCdk"}}}]}
[@jsii/kernel] create {
  api: 'create',
  fqn: 'aws-cdk-lib.aws_cloudfront.CfnFunction',
  args: [
    { '$jsii.byref': 'aws-cdk-lib.Stack@10001' },
    'myCDKFunction',
    { '$jsii.struct': [Object] }
  ]
}
[@jsii/kernel] toSandbox { '$jsii.byref': 'aws-cdk-lib.Stack@10001' } [{"serializationClass":"RefType","typeRef":{"docs":{"summary":"- scope in which this resource is defined."},"name":"scope","type":{"fqn":"constructs.Construct"}}}]
[@jsii/kernel] toSandbox myCDKFunction [{"serializationClass":"Scalar","typeRef":{"docs":{"summary":"- scoped id of the resource."},"name":"id","type":{"primitive":"string"}}}]
[@jsii/kernel] toSandbox {
  '$jsii.struct': {
    fqn: 'aws-cdk-lib.aws_cloudfront.CfnFunctionProps',
    data: {
      autoPublish: true,
      functionCode: 'hi',
      functionConfig: [Object],
      name: 'myCfnFunctionCdk'
    }
  }
} [{"serializationClass":"Struct","typeRef":{"docs":{"summary":"- resource properties."},"name":"props","type":{"fqn":"aws-cdk-lib.aws_cloudfront.CfnFunctionProps"}}}]
[@jsii/kernel] toSandbox true [{"serializationClass":"Scalar","typeRef":{"type":{"primitive":"boolean"},"optional":true}},{"serializationClass":"RefType","typeRef":{"type":{"fqn":"aws-cdk-lib.IResolvable"},"optional":true}}]
[@jsii/kernel] toSandbox hi [{"serializationClass":"Scalar","typeRef":{"abstract":true,"docs":{"custom":{"link":"http://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-cloudfront-function.html#cfn-cloudfront-function-functioncode"},"stability":"external","summary":"`AWS::CloudFront::Function.FunctionCode`."},"immutable":true,"locationInModule":{"filename":"lib/aws-cloudfront/lib/cloudfront.generated.ts","line":3191},"name":"functionCode","optional":true,"type":{"primitive":"string"}}}]
[@jsii/kernel] toSandbox { '$jsii.byref': 'Object@10002' } [{"serializationClass":"Struct","typeRef":{"type":{"fqn":"aws-cdk-lib.aws_cloudfront.CfnFunction.FunctionConfigProperty"},"optional":true}},{"serializationClass":"RefType","typeRef":{"type":{"fqn":"aws-cdk-lib.IResolvable"},"optional":true}}]
[@jsii/kernel] Expected value type but got reference type, accepting for now (awslabs/jsii#400)
[@jsii/kernel] toSandbox myCfnFunctionCdk [{"serializationClass":"Scalar","typeRef":{"abstract":true,"docs":{"custom":{"link":"http://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-cloudfront-function.html#cfn-cloudfront-function-name"},"stability":"external","summary":"`AWS::CloudFront::Function.Name`."},"immutable":true,"locationInModule":{"filename":"lib/aws-cloudfront/lib/cloudfront.generated.ts","line":3181},"name":"name","type":{"primitive":"string"}}}]
< {"ok":{"$jsii.byref":"aws-cdk-lib.aws_cloudfront.CfnFunction@10003"}}
> {"api":"invoke","method":"synth","args":[null],"objref":{"$jsii.byref":"aws-cdk-lib.App@10000"}}
[@jsii/kernel] invoke { '$jsii.byref': 'aws-cdk-lib.App@10000' } synth [ null ]
[@jsii/kernel] toSandbox null [{"serializationClass":"Struct","typeRef":{"name":"options","optional":true,"type":{"fqn":"aws-cdk-lib.StageSynthesisOptions"}}}]
panic: "Resolution error: Supplied properties not correct for \"CfnFunctionProps\"\n  functionConfig: supplied properties not correct for \"FunctionConfigProperty\"\n    comment: required but missing\n    runtime: required but missing."

goroutine 1 [running]:
github.com/aws/jsii-runtime-go/runtime.Invoke(0x1534b20, 0xc0003320d0, 0x158cfe0, 0x5, 0xc0004bbec8, 0x1, 0x1, 0x14ae9e0, 0xc0003328b0)
	/Users/nlynch/go/pkg/mod/github.com/aws/[email protected]/runtime/runtime.go:214 +0x2b7
github.com/aws/aws-cdk-go/awscdk/v2.(*jsiiProxy_App).Synth(0xc0003320d0, 0x0, 0x15943ac, 0x11)
	/Users/nlynch/go/pkg/mod/github.com/aws/aws-cdk-go/awscdk/[email protected]/awscdk.go:324 +0xb5
main.main()
	/var/folders/cf/ttmfqtv97z13mfktyqcjgq040000gr/T/tmp.YbIgojCg/gocloudfront/gocloudfront.go:48 +0xfa
exit status 2
�[31mSubprocess exited with error 1�[39m

To me, the interesting bit appears to be that -- unlike the other objects -- the FunctionConfig is created without any fqn info or args.

> {"api":"create","fqn":"Object"}
[@jsii/kernel] create { api: 'create', fqn: 'Object' }
< {"ok":{"$jsii.byref":"Object@10002"}}

Compared to the Function itself:

> {"api":"create","fqn":"aws-cdk-lib.aws_cloudfront.CfnFunction","args":[{"$jsii.byref":"aws-cdk-lib.Stack@10001"},"myCDKFunction",{"$jsii.struct":{"fqn":"aws-cdk-lib.aws_cloudfront.CfnFunctionProps","data":{"autoPublish":true,"functionCode":"hi","functionConfig":{"$jsii.
byref":"Object@10002"},"name":"myCfnFunctionCdk"}}}]}
[@jsii/kernel] create {
  api: 'create',
  fqn: 'aws-cdk-lib.aws_cloudfront.CfnFunction',
  args: [
    { '$jsii.byref': 'aws-cdk-lib.Stack@10001' },
    'myCDKFunction',
    { '$jsii.struct': [Object] }
  ]
}

[MrArnoldPalmer]

So this works without the pointer type, but I believe this is a bug. This compiles and runs.

	cf.NewCfnFunction(stack, jsii.String("myCDKFunction"), &cf.CfnFunctionProps{
		Name:         jsii.String("myCfnFunctionCdk"),
		FunctionCode: jsii.String("myFunctionCode"),
		AutoPublish:  jsii.Bool(true),
		FunctionConfig: cf.CfnFunction_FunctionConfigProperty{
			Comment: jsii.String("testcdk"),
			Runtime: jsii.String("cloudfront-js-1.0"),
		},
	})

The generated type of CfnFunctionProps is as follows:

type CfnFunctionProps struct {
	Name *string `json:"name"`
	AutoPublish interface{} `json:"autoPublish"`
	FunctionCode *string `json:"functionCode"`
	FunctionConfig interface{} `json:"functionConfig"`
	FunctionMetadata interface{} `json:"functionMetadata"`
}

I believe the FunctionConfig property type should be *CfnFunction_FunctionConfigProperty. @RomainMuller am I missing something in this case?

[RomainMuller]

According to the documentation, the FunctionConfig property is a type union (IResolvable | FunctionConfigProperty). This effectively means the property can only be typed as interface{} in Go.

That being said, the serialiser should probably be able to work it out whether a pointer is used or not in this particular case (since the value is a struct). It might fall in an crack in the current logic.

[github-actions]

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