"No operations defined in spec!" is shown with path with $ref in 3.13.0 version

[jiguillen]

Q	A
Bug or feature request?	Bug
Which Swagger/OpenAPI version?	OpenAPI 3.0
Which Swagger-UI version?	3.13.0
How did you install Swagger-UI?	Using swaggerapi/swagger-ui docker
Which browser & version?	Chrome Versión 64.0.3282.186
Which operating system?	Linux Mint 18 Sarah

Demonstration API definition

openapi: "3.0.0"
info:
  version: 1.0.0
  title: Swagger Petstore
  license:
    name: MIT
servers:
  - url: http://petstore.swagger.io/v1
paths:
  /pets:
    $ref : './doc/paths/pets.yaml#/pets'
components:
  schemas:
    Pet:
      required:
        - id
        - name
      properties:
        id:
          type: integer
          format: int64
        name:
          type: string
        tag:
          type: string
    Pets:
      type: array
      items:
        $ref: "#/components/schemas/Pet"
    Error:
      required:
        - code
        - message
      properties:
        code:
          type: integer
          format: int32
        message:
          type: string

Configuration (browser query string, constructor, config.yaml)

Configuration by default in swaggerapi/swagger-ui docker

Expected Behavior

Can see /pets path

Current Behavior

"No operations defined in spec!" is shown

Possible Solution

It is was working in version 3.10.0

Context

I've updated from 3.10.0 to 3.13.0 version and it has stopped working.
File ./doc/paths/pets.yaml exists and it is well formed.

[shockey]

Thanks for the report, @jiguillen - I bumped into this while helping out on a support ticket, and have already started on a fix!

[shockey]

The depth option mentioned in #4280 would be helpful in limiting the performance hit we'll get from resolving path items at load time.

[glipman]

I am not entirely sure if delayed resolving for paths is possible: a remote path item may define a tag.
Swagger UI uses tags to group the displayed operations. The resolved path item is needed even to display the collapsed items under the correct tag.

[shockey]

@glipman yeah, my solution is likely going to be check for $ref at the path level, and if it's there, go ahead and resolve.

Using https://gist.github.com/shockey/8c60fc810aa513fb27c9d4f025d0ac16 to test.

[shockey]

fixed! thanks for the report, @jiguillen 👍

[heldersepu]

I noticed that this No operations defined in spec! also shows when we use the filter
http://petstore.swagger.io/?filter=NoOp
Every time we search for something that does not exist that is what we get...

[shockey]

@heldersepu, yeah that's been around since 3.0.0 I believe. it's a different root cause: the filter is modifying the output of a selector (taggedOperations iirc), so that when no operations match, the data flowing into the component is indistinguishable from a definition that has no operations.

There's ways to fix that, but they aren't closely related to this issue 😄

[lock]

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