Remaining Coverage Gaps in Resource Docs

[lukehoban]

The new resource docs provide a high quality cross-language experience for the majority of Pulumi APIs. However, they have some coverage gaps that mean they do not present the full API, which can be misleading, leads to inconsistency, and increases the dependence on language-specific API docs.

Known coverage gaps:

• Top-level config module in ~all current providers (No docs for config module #3641)
• Enums - Node.js specific (but should probably be addressed by making these non-Node.js specific) (aws.InstanceTypes and many more) Add enum support to the schema and code generators pulumi#4003
• JSON types - Node.js specific (but should probably be addressed by making these non-Node.js specific) (aws.iam.PolicyDocument) Add support for typed JSON objects in the schema code generator and terraform-bridge pulumi-terraform-bridge#132
• Resources that take callback, and methods that accept callbacks - Node.js specific (aws.lambda.CallbackFunction, aws.cloudwatch.onSchedule, etc.) Support function types in schema pulumi#4785
• Component Packages - Node.js specific (awsx, eks, cloud, kubernetesx) Add ComponentResource support to Schema pulumi#4784
• Component Resource in existing packages - all languages (docker.Image) Add documentation for docker.Image pulumi-docker#111
• Hand-rolled native provider - all languages (terraform) Add resource docs for terraform package pulumi-terraform#727

We might be able to address some of these with docs "overlays" as in https://github.com/pulumi/docs/blob/master/tools/resourcedocsgen/overlays/kubernetes/overlays.json. But where possible, we should aim to generalize our schema to support expressing these concepts so they can be authored and maintained as part of the package itself.