fix(rest): allow @patch update obj to be a Partial

[joeytwiddle]

This changes the type of the obj argument in @patch endpoints from Model to Partial<Model>.

Since the route checking has become more strict, requests to patch only some fields of a document are now being rejected, because the validation expects to see all required fields in the patch.

In our codebase, we have made the type of the update object Partial<Model> to allow partial updates, and that has been working well.

This is only a quick fix. I believe you may settle on a more comprehensive solution later, as discussed in #1722

• I used Partial<Model> because I thought that was more appropriate than DeepPartial<Model> or DataObject<Model> but I could be wrong.

If this PR is not a step in the desired direction, then please feel free to close it.

Checklist

• npm test passes on your machine
  I'm afraid the develop branch is currently failing for me with: Conflicting definitions for 'express-serve-static-core'
• New tests added or existing tests modified to cover all changes
• Code conforms with the style guide
• API Documentation in code was updated
• Documentation in /docs/site was updated
• Affected artifact templates in packages/cli were updated
• Affected example projects in examples/* were updated

[bajtos]

@joeytwiddle thank you for opening this pull request. The proposed changes are going in the right direction, but I am don't think we have the required underlying block already in place.

-    @requestBody() data: Todo,
+    @requestBody() data: Partial<Todo>,

The way how @requestBody() currently works: it's using the so-called design:type metadata produced by TypeScript to learn about the type of the argument value (a Todo constructor). When this design:type is a model, then the decorator emits a JSON/OpenAPI schema describing model properties as the accepted value.

When you change the type from Todo to Partial<Todo>, this metadata is lost and @requestBody() decorator sees only a generic object type. As a result, the OpenAPI spec describing application's REST API is describing the endpoint as accepting an empty object. At least that's what I remember - could you please check the actual behavior yourself?

If my description above still holds, then we need to find a way how to explicitly tell requestBody decorator what type is the parameter accepting, before we can change the CRUD Controller template used by our CLI. See the discussion in #1722 for implementation proposals.

Would you like to take a look at this underlying feature first?

[bajtos]

☝️

[ambrt]

-    @requestBody() data: Todo,
+    @requestBody() data: Partial<Todo>

As a result, the OpenAPI spec describing application's REST API is describing the endpoint as accepting an empty object. At least that's what I remember - could you please check the actual behavior yourself?

I can confirm - Partial<Todo> describes endpoint as accepting empty object.

[bajtos]

I am closing this pull request as abandoned, feel free to reopen if you get time to work on this again.