GET /ping is missing content object in the OAS

[Alan-Cha]

Description

The a new LoopBack app automatically creates a GET /ping operation but the operation is missing a content object, aka media type object.

Step to reproduce

Create a new Loopback project, start the API, and find the OAS (go to http://localhost:3000/openapi.json).

lb4 app
cd [app name]
npm start

Current behavior

"/ping": {
      "get": {
        "x-controller-name": "PingController",
        "x-operation-name": "ping",
        "tags": [
          "PingController"
        ],
        "responses": {
          "200": {
            "description": "Return value of PingController.ping"
          }
        }
      }
    }
  }

Expected behavior

"/ping": {
  "get": {
    "x-controller-name": "PingController",
    "x-operation-name": "ping",
    "tags": [
      "PingController"
    ],
    "responses": {
      "200": {
        "description": "Return value of PingController.ping",
        "content": {
          "application/json": {
            "schema": {
              "type": "object",
              "properties": {
                "greeting": {
                  "type": "string"
                },
                "date": {
                  "type": "string"
                },
                "url": {
                  "type": "string"
                },
                "headers": {
                  "type": "object",
                  "properties": {
                    "cache-control": {
                      "type": "string"
                    },
                    "postman-token": {
                      "type": "string"
                    },
                    "user-agent": {
                      "type": "string"
                    },
                    "accept": {
                      "type": "string"
                    },
                    "host": {
                      "type": "string"
                    },
                    "accept-encoding": {
                      "type": "string"
                    },
                    "connection": {
                      "type": "string"
                    }
                  }
                }
              }
            }
          }
        }
      }
    }
  }
}

In theory you should just be able to copy and paste the content object into the template but I am unsure of the data types for cache-control, postmanToken, and userAgent.

[raymondfeng]

See loopbackio/loopback4-example-shopping@2258e98