Support object schemas in query items

[czechboy0]

We should support encoding non-primitive values as query items, which is prescribed by OpenAPI.

        - name: fields
          in: query
          description: Pairs of field=value to filter results
          required: true
          schema:
            type: object
            additionalProperties:
              type: string

The above example also uses additionalProperties, but I think that shouldn't change the story around serializing object structs into query items.

Somewhat related to #18.

This issue was also encountered in #83.

[sliemeobn]

since the docs suggest that "in: query + style: form + exploded: true" is supported I stumbled over this when writing a new server (slack thread)

I was going by this example from the swagger docs:

Objects can be serialized as:
form – /points?color=R,100,G,200,B,150 or /points?R=100&G=200&B=150, depending on the explode keyword

my desired route would look like this:

  /users:
    get:
      operationId: getUsers
      parameters:
      - name: filter
        in: query
        schema:
          type: object
          properties:
            name: { type: string }
            group: { type: string }
            role: { type: string }
        explode: true
        style: form

however, the generated code produces an error around the conversion:

error: instance method 'setQueryItemAsText(in:name:value:)' requires that 'Operations.getUsers.Input.Query.filterPayload' conform to '_StringConvertible'
                try converter.setQueryItemAsText(

in the generated deserializer code (UniversalServer extension)

    func getUsers(request: Request, metadata: ServerRequestMetadata) async throws -> Response {
        try await handle(
            request: request,
            with: metadata,
            forOperation: Operations.getUsers.id,
            using: APIHandler.getUsers,
            deserializer: { request, metadata in let path: Operations.getUsers.Input.Path = .init()
                let query: Operations.getUsers.Input.Query = .init(
                    filter: try converter.getOptionalQueryItemAsText(
                        in: metadata.queryParameters,
                        name: "filter",
                        as: Operations.getUsers.Input.Query.filterPayload.self
                    )
                )

in addition of this being a really useful feature, it feels to me that the docs are incorrectly suggesting that this is supported.
edit: just realized the docs do state that only primitive and array is supported, I just didn't rtfm correcly ; )

[sliemeobn]

bonus fact: I also intended to use this for a nice, shared "pagination" definition for all fetching endpoints

by defining this

components:
  parameters:
    Pagination:
      name: pagination
      in: query
      schema: { $ref: "#/components/schemas/Pagination" }
      explode: true
      style: form
  schemas:
    Pagination:
      type: object
      properties:
        page: { type: number, default: 1 }
        perPage: { type: number, default: 50 }

I was hoping I could just add "pagination" like that

  /users:
    get:
      operationId: getUsers
      parameters:
      - name: filter
      # some filter schema here #
      # ...
      - $ref: "#/components/parameters/Pagination"

[czechboy0]

The new URIEncoder/Decoder should hopefully lead to this being addressed relatively soon. #192

[czechboy0]

Verified that this gets resolved by #226.

[wangzhizhou]

Verified that this gets resolved by #226.

Great I will have a try. Thank you for your job

[wangzhizhou]

I use the package:

.package(url: "https://github.com/czechboy0/swift-openapi-generator.git", branch: "hd-uri-encoder-integration")