External URL ref and oneOf broken generated code

[insidieux]

Version

master (SHA fec990c8f82)

Config

package: openapi
generate:
  gorilla-server: true
  client: true
  models: true
output: pkg/openapi/generated.go
import-mapping:
  'https://raw.githubusercontent.com/deepmap/oapi-codegen/master/examples/petstore-expanded/petstore-expanded.yaml': github.com/deepmap/oapi-codegen/examples/petstore-expanded

Spec

openapi: "3.0.0"
info:
  version: 1.0.0
  title: Example broken generation with oneOf and external remote ref
paths:
  /check:
    get:
      summary: Return broken example
      responses:
        '200':
          description: Ok
          content:
            application/json:
              schema:
                items:
                  $ref: '#/components/schemas/exampleSchema'
components:
  schemas:
    exampleSchema:
      properties:
        item:
          type: object
          oneOf:
            - $ref: 'https://raw.githubusercontent.com/deepmap/oapi-codegen/master/examples/petstore-expanded/petstore-expanded.yaml#/components/schemas/NewPet'
      required:
        - item

Problems

Running command oapi-codegen --config config.yaml spec.yaml failed with error

Error openapi.go:61:51: expected '(', found '.' (and 2 more errors)

If watch output, we'll see broken generated methods As/From/Merge for exampleSchema.item: generator put union type name as is with dot in name externalRef\d+.SchemaName:

// AsexternalRef0.NewPet returns the union data inside the ExampleSchema_Item as a externalRef0.NewPet
        func (t ExampleSchema_Item) AsexternalRef0.NewPet() (externalRef0.NewPet, error) {
            var body externalRef0.NewPet
            err := json.Unmarshal(t.union, &body)
            return body, err
        }

        // FromexternalRef0.NewPet overwrites any union data inside the ExampleSchema_Item as the provided externalRef0.NewPet
        func (t *ExampleSchema_Item) FromexternalRef0.NewPet (v externalRef0.NewPet) error {
            b, err := json.Marshal(v)
            t.union = b
            return err
        }

        // MergeexternalRef0.NewPet performs a merge with any union data inside the ExampleSchema_Item, using the provided externalRef0.NewPet
        func (t *ExampleSchema_Item) MergeexternalRef0.NewPet (v externalRef0.NewPet) error {
            b, err := json.Marshal(v)
            if err != nil {
              return err
            }

            merged, err := runtime.JsonMerge(b, t.union)
            t.union = merged
            return err
        }

Generated code with enabled gorilla-server does not generate import gorilla/mux

This just can be fixed by adding

additional-imports:
  - package: github.com/gorilla/mux

But... seems like it must be automatically added by enabling gorilla generator.

[technicianted]

I ran into this problem too and I fixed it in my private build. However I ran into another problem of oneOf external ref that itself referencing an external type #729.