API Mocking (mocking)

Description

The mocking Plugin allows you to simulate API responses without forwarding requests to Upstream services. The Plugin supports customization of the response status code, body, headers, and more. This is particularly useful during development, testing, or debugging phases, where the actual Upstream service might be unavailable, under maintenance, or expensive to call.

Attributes

Name	Type	Required	Default	Description
delay	integer	False	0	Response delay in seconds.
response_status	integer	False	200	HTTP status code of the response.
content_type	string	False	application/json;charset=utf8	Content-Type header value of the response.
response_example	string	One of this or response_schema		Body of the response. Supports NGINX variables, such as $remote_addr. One of response_example or response_schema must be configured, and they must not be configured together.
response_schema	object	One of this or response_example		A JSON schema object to generate a random mock response body. One of response_schema or response_example must be configured, and they must not be configured together.
with_mock_header	boolean	False	true	When set to true, adds a response header x-mock-by: APISIX/{version}.
response_headers	object	False		Headers to be added in the mocked response. For example: {"X-Foo": "bar"}.

The response_schema supports the following field types:

• string
• number
• integer
• boolean
• object
• array

Examples

The examples below demonstrate how you can configure mocking on a Route in different scenarios.

note

You can fetch the admin_key from config.yaml and save to an environment variable with the following command:

admin_key=$(yq '.deployment.admin.admin_key[0].key' conf/config.yaml | sed 's/"//g')

Generate Specific Mock Responses

The following example demonstrates how to configure the Plugin to generate a specific mock response and response status code without forwarding the request to the Upstream service.

Create a Route with the mocking Plugin:

curl "http://127.0.0.1:9180/apisix/admin/routes" -X PUT \
  -H "X-API-KEY: ${admin_key}" \
  -d '{
    "id": "mocking-route",
    "uri": "/anything",
    "plugins": {
      "mocking": {
        "response_status": 201,
        "response_example": "{\"Lastname\":\"Brown\",\"Age\":56}"
      }
    },
    "upstream": {
      "type": "roundrobin",
      "nodes": {
        "httpbin.org:80": 1
      }
    }
  }'

Send a request to the Route:

curl -i "http://127.0.0.1:9080/anything"

You should receive an HTTP/1.1 201 Created mock response with the following body:

{"Lastname":"Brown","Age":56}

Generate Mock Response Headers

The following example demonstrates how to configure the Plugin to generate mock response headers and use a built-in NGINX variable in the response body.

Create a Route with the mocking Plugin:

curl "http://127.0.0.1:9180/apisix/admin/routes" -X PUT \
  -H "X-API-KEY: ${admin_key}" \
  -d '{
    "id": "mocking-route",
    "uri": "/anything",
    "plugins": {
      "mocking": {
        "response_headers": {
          "X-User-Id": "100",
          "X-Product-Id": "apac-398-472"
        },
        "response_example": "Client IP: $remote_addr"
      }
    },
    "upstream": {
      "type": "roundrobin",
      "nodes": {
        "httpbin.org:80": 1
      }
    }
  }'

Send a request to the Route:

curl -i "http://127.0.0.1:9080/anything"

You should receive a response similar to the following:

HTTP/1.1 200 OK
...
X-Product-Id: apac-398-472
X-User-Id: 100

Client IP: 192.168.65.1

Generate Mock Responses Using JSON Schema

The following example demonstrates how to configure the Plugin to generate mock responses following a specific JSON schema.

Create a Route with the mocking Plugin and define a JSON schema for the expected mock responses:

curl "http://127.0.0.1:9180/apisix/admin/routes" -X PUT \
  -H "X-API-KEY: ${admin_key}" \
  -d '{
    "id": "mocking-route",
    "uri": "/anything",
    "plugins": {
      "mocking": {
        "response_schema": {
          "type": "object",
          "properties": {
            "id": {
              "type": "string",
              "example": "abcd"
            },
            "ip": {
              "type": "number",
              "example": 192.168
            },
            "random_str_arr": {
              "type": "array",
              "items": {
                "type": "string"
              }
            },
            "nested_obj": {
              "type": "object",
              "properties": {
                "random_str": {
                  "type": "string"
                },
                "child_nested_obj": {
                  "type": "object",
                  "properties": {
                    "random_bool": {
                      "type": "boolean",
                      "example": true
                    },
                    "random_int_arr": {
                      "type": "array",
                      "items": {
                        "type": "integer",
                        "example": 155
                      }
                    }
                  }
                }
              }
            }
          }
        }
      }
    },
    "upstream": {
      "type": "roundrobin",
      "nodes": {
        "httpbin.org:80": 1
      }
    }
  }'

Send a request to the Route:

curl -i "http://127.0.0.1:9080/anything"

You should see a mock response similar to the following, without an actual response from the Upstream service:

{
  "ip": 192.168,
  "random_str_arr": [
    "fb", "lyquibkwc", "r"
  ],
  "id": "abcd",
  "nested_obj": {
    "random_str": "bzbb",
    "child_nested_obj": {
      "random_bool": true,
      "random_int_arr": [155, 155, 155]
    }
  }
}