Issue Summary

Open API Spec for the multiple Confluence Cloud REST APIs uses "allof" composition for the response, which overrides the "_links" value containing only the "base" parameter value with the ones available in the $ref objects.

Confluence Cloud REST APIs affected :

/pages/{id}
/blogposts/{id}
/attachments/{id}
/custom-content/{id}
/databases, /databases/{id}
/folders, /folders/{id}
/embeds/{id}, /embeds
/whiteboards, /whiteboards/{id}
 

Steps to Reproduce

1. Download the OpenAPI definition from Confluence Cloud Open API.

1. Below API spec for /pages/{id} REST call overrides the value of $ref object PageSingle due to "allof" composition resulting in "_links" containing only the "base" parameter value in the response for the client generated code.

   /pages/{id}:
       get:
         tags:
           - Page
         operationId: getPageById
         summary: Get page by id
         description: |-
           Returns a specific page.
   .
   .
   responses:
           '200':
             description: Returned if the requested page is returned.
             content:
               application/json:
                 schema:
                   allOf:
                     - $ref: '#/components/schemas/PageSingle'
                     - type: object
                       properties:
                         _links:
                           type: object
                           properties:
                             base:
                               type: string
                               description: Base url of the Confluence site.
      

Expected Results

The "_links" should contain response parameters available in $ref object for the corresponding REST API(such as "editui", "webui", "tinyui", and "edituiv2" for /pages/{id}).

{
.
.
. 
"_links": {
        "editui": "/pages/resumedraft.action?draftId=229474",
        "webui": "/spaces/~63749c013c26ca7fa0d102e4/overview",
        "edituiv2": "/spaces/~63749c013c26ca7fa0d102e4/pages/edit-v2/229474",
        "tinyui": "/x/YoAD",
        "base": "https://*****.atlassian.net/wiki"
    }
} 

Actual Results

The results returned from the generated client code contain "links" with only the base parameter value.

{
.
.
.
  "links": {
    "base": "https://******.atlassian.net/wiki"
  }
}  

Workaround

Enhance _link schemas with missing properties or replace problematic allOf compositions with direct $ref to Single schemas.