Test Assertions¶

Besides enabling you to set-up APIs, mock provides you with methods to make assertions on how your endpoints were called.

Test Assertions are done by calling the POST localhost:3000/__mock__/assert endpoint.

In case you’re new to the concept of automated tests and assertions - let’s see what a very simple assertion looks like:

{
  "route": "hello/world",
  "condition": {
    "type": "method_match",
    "value": "put"
  }
}

Or if we could say it in plain english: the endpoint hello/world was requested with the put method.

In case there was never a call to that particular endpoint, you would then get a response from mock indicating that no request has been made:

{
  "validation_errors": [
    {
      "code": "no_call",
      "metadata": {}
    }
  ]
}

However in case a request had been made to that endpoint, with the, say, POST method, you would then get a different validation error, because you attempted to assert that it was called with the PUT method instead:

{
  "validation_errors": [
    {
      "code": "method_mismatch",
      "metadata": {
        "method_expected": "put",
        "method_requested": "post"
      }
    }
  ]
}

mock tells you whether the assertion passed or not by including “Validation Errors” into the validation_errors response field. Another indicative is the Response Status - 200 is success, 400 means your assertion failed.

With that we’ve seen a very simple assertion. There are other things that can be asserted in a HTTP Request, such as the header values passed, the body payload etc. For a reference of all available condition options, skip to this section.

Which Request to assert against?¶

By default, Assertions are based on the 1st Request. In cases where you want to assert against a Request other than the first, you’ll use the nth Assertion Option.

 {
   "route": "foo/bar",
+  "nth": 2,
   "condition": {
     "type": "method_match",
     "value": "post"
   }
 }

Contents: