Errors displaying schemas with oneOf about swagger-ui

[glowcloud]

The issue on the surface looks like it was introduced by 7300e6c but it seems like it actually uncovered a different issue, which you can see in Swagger Editor.

The names there are displayed correctly:

but if we actually expand the schemas:

you can see that additionalData from FirstOneOf is missing and the references are also not resolved properly.

The resolved subtree for OneOfParent:

{
    "title": "OneOfParent",
    "properties": {
        "additionalData": {
            "oneOf": [
                {
                    "$ref": "http://localhost:3200/examples/regressionJson.json#/components/schemas/OneOfParent",
                    "properties": {
                        "numberProp": {
                            "type": "number",
                            "example": "1"
                        }
                    },
                    "type": "object",
                    "title": "FirstOneOf",
                    "$$ref": "http://localhost:3200/examples/regressionJson.json#/components/schemas/FirstOneOf"
                },
                {
                    "$ref": "http://localhost:3200/examples/regressionJson.json#/components/schemas/OneOfParent",
                    "properties": {
                        "person": {
                            "properties": {
                                "id": {
                                    "type": "string"
                                }
                            },
                            "type": "object"
                        }
                    },
                    "type": "object",
                    "title": "SecondOneOf",
                    "$$ref": "http://localhost:3200/examples/regressionJson.json#/components/schemas/SecondOneOf"
                },
                {
                    "$ref": "http://localhost:3200/examples/regressionJson.json#/components/schemas/OneOfParent",
                    "properties": {
                        "person": {
                            "properties": {
                                "id": {
                                    "type": "string"
                                },
                                "name": {
                                    "type": "string"
                                },
                                "surname": {
                                    "type": "string"
                                }
                            },
                            "type": "object"
                        }
                    },
                    "type": "object",
                    "title": "ThirdOneOf",
                    "$$ref": "http://localhost:3200/examples/regressionJson.json#/components/schemas/ThirdOneOf"
                }
            ]
        }
    },
    "type": "object"
}

We can see both the resolved $$ref and unresolved $ref - because of this the names are different and we only get the schema under $ref, as that was one of the changes in this commit 7300e6c

If we expand FirstOneOf first and then OneOfParent, we'll get this:

This looks to me like an issue with the resolver - perhaps with allOf and circular / unresolved references.

[glowcloud]

In theory, we could pass fn to our Model component and use mergeJsonSchema - in place of

swagger-ui/src/core/components/model.jsx

Lines 72 to 82 in 6e91056

	if ($ref) {
	name = this.getModelName($ref)
	const refSchema = this.getRefSchema(name)
	if (Map.isMap(refSchema)) {
	schema = refSchema.set("$$ref", $ref)
	$$ref = $ref
	} else {
	schema = null
	name = $ref
	}
	}

have something like this:

if ($ref) {
   const refName = this.getModelName($ref)
   const refSchema = this.getRefSchema(refName)
   if (Map.isMap(refSchema)) {
     schema = fromJS(fn.mergeJsonSchema(schema.toJS(), refSchema.toJS()))
     name = name || refName
     if (!$$ref) {
       schema = schema.set("$$ref", $ref)
       $$ref = $ref
     }
   } else if (!$$ref) {
     schema = null
     name = $ref
   }
 }

this will work for the spec in the issue:

But it will not solve it for cases where we have more than one circular reference, as the $ref property will get replaced by the next defined $ref. To illustrate it, we can have this spec:

{
  "openapi": "3.0.0",
  "info": {
    "title": "Test",
    "description": "Test",
    "license": {
      "name": "Apache 2.0",
      "url": "https://www.apache.org/licenses/LICENSE-2.0.html"
    },
    "version": "1.0"
  },
  "servers": [
    {
      "url": "https://localhost:8000"
    }
  ],
  "components": {
    "schemas": {
      "Parent": {
        "title": "Parent",
        "properties": {
          "parentData": {
            "$ref": "#/components/schemas/OneOfParent"
          }
        },
        "type": "object"
      },
      "OneOfParent": {
        "title": "OneOfParent",
        "properties": {
          "additionalData": {
            "oneOf": [
              {
                "$ref": "#/components/schemas/FirstOneOf"
              }
            ]
          }
        },
        "type": "object"
      },
      "FirstOneOf": {
        "title": "FirstOneOf",
        "type": "object",
        "allOf": [
          {
            "$ref": "#/components/schemas/Parent"
          },
          {
            "$ref": "#/components/schemas/OneOfParent"
          },
          {
            "properties": {
              "numberProp": {
                "type": "number",
                "example": "1"
              }
            },
            "type": "object"
          }
        ]
      }
    }
  }
}

and our rendered model will be missing parentData:

If we swap the order of references in allOf in FirstOneOf:

"FirstOneOf": {
      "title": "FirstOneOf",
      "type": "object",
      "allOf": [
        {
          "$ref": "#/components/schemas/OneOfParent"
        },
        {
          "$ref": "#/components/schemas/Parent"
        },
        {
          "properties": {
            "numberProp": {
              "type": "number",
              "example": "1"
            }
          },
          "type": "object"
        }
      ]
    }

This time additionalData will be missing:

It looks to me like we would somehow need to keep these unresolved $refs in an array (as $ref: [<unresolved_ref_0>, <unresolved_ref_1>, ...]) instead of only having a string there, that gets replaced when we get another $ref

[char0n]

• we will assume that every schema with $ref field and one or more additional fields is a result of allOf keyword merge
• given that Reference Object cannot have any additional fields than $ref, the assumption is almost correct
• we will use Immutable.mergeDeep to merge the referenced schema with the referencing one (which makes it compatible with swagger-client allOf specmap plugin)
• this can introduce possible circular references (cycles) again into the deferenced tree

[char0n]

Addressed in #9794