[JSON Schema] Customize names of properties

[masp]

» pkl --version
Pkl 0.25.1 (macOS 14.1, native)

org.json_schema.contrib.generate = 1.0.0

Context

I am hoping to use Pkl to define AWS Cloudformation templates for creating infrastructure as an alternative to defining them in JSON or using CDK. I saw the new JSON schema generator and received the following output:

Command

pkl eval package://pkg.pkl-lang.org/pkl-pantry/[email protected]#/generate.pkl -m cfnpkl -p source="cfn/aws-s3-bucket.json"

Error

The generation looks great, but it produces an output that looks like (unimportant fields omitted):

...
/// Configuration for the transfer acceleration state.
AccelerateConfiguration: Mapping<String, Any>?
...
class AccelerateConfiguration {
  /// Configures the transfer acceleration state for an Amazon S3 bucket.
  AccelerationStatus: "Enabled"|"Suspended" = Undefined()
}

Because in Cloudformation all fields are capitalized pascal case, there is a conflict between the type and the property name in the module. If I try to import the generated pkl file, I receive the following error on render:

test.pkl

import "cfn.pkl"

resources {
    ["MyBucket"] = new AwsS3Bucket {
        BucketName = "mybucket"
    }
}

Documents/pkl-test » pkl eval test.pkl
–– Pkl Error ––
Duplicate definition of member `AccelerateConfiguration`.

10 | AccelerateConfiguration: Mapping<String, Any>?
     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
at test#AwsS3Bucket (file:///Users/markasp/Documents/pkl-test/cfnpkl/AwsS3Bucket.pkl, line 10)

5 | ["MyBucket"] = new AwsS3Bucket {
                       ^^^^^^^^^^^
at test#resources["MyBucket"] (file:///Users/markasp/Documents/pkl-test/test.pkl, line 5)

106 | text = renderer.renderDocument(value)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
at pkl.base#Module.output.text (https://github.com/apple/pkl/blob/0.25.1/stdlib/base.pkl#L106)

There also seems to be a tangential bug where the property name is not associated with the type correctly. The JSON schema looks like:

"definitions": {
  "AccelerateConfiguration" : {
      "type" : "object",
      "additionalProperties" : false,
      "properties" : {
        "AccelerationStatus" : {
          "description" : "Configures the transfer acceleration state for an Amazon S3 bucket.",
          "type" : "string",
          "enum" : [ "Enabled", "Suspended" ]
        }
      },
      "required" : [ "AccelerationStatus" ]
    },
},
...
"properties": {
  "AccelerateConfiguration" : {
      "$ref" : "#/definitions/AccelerateConfiguration",
      "description" : "Configuration for the transfer acceleration state."
    },
}

Proposed Fix

Ideally, I'd like the property names to be lowercased and the class names to be capitalized like they are. This would make the definitions very ergonomic:

resources {
  ["MyBucket"] = new AwsS3Bucket {
    bucketName = "mybucket"
  }
}

and then I can define a converter to make it capitalized in the JSON output. Maybe a parameter on generate that allows it to transform key names in the output similar to the syntax for converters in rendering:

output {
  renderer = new JsonRenderer {
    converters {
      [Object] = (it) -> it.toMap().mapKeys((k, _) -> k.capitalize())
    }
  }
}