Mock an HTTP response from within Elm.

Specify exactly what you'd like the response of an HTTP request to be. The actual response of the HTTP request is ignored - the response will be exactly what you want to be mocked!

Here's some ways this can be useful.

Testing your code

Not sure how your code handles an HTTP request that results in a Timeout? Test it by mocking a Timeout response!

import Http
import Http.Mock


type Msg
    = MyResponseHandler (Result Http.Error String)


testTimeout =
    Http.get
        { url = "https://fakeurl.com"
        , expect = Http.Mock.expectString Http.Timeout_ MyResponseHandler
        }

Your update logic doesn't change - mock a Timeout response and make sure your application handles it correctly! Notice that we put in a dummy URL here - It doesn't matter request you make, as the response of the request will be exactly what you specify.

Mocking an API

Need to quickly mock an API locally? Don't waste time setting up a fake HTTP server for testing - just mock the response directly from within Elm!

import Http
import Http.Mock


type Msg
    = MyResponseHandler (Result Http.Error String)


-- This is our mocked response.
-- You would actually put metadata and a body!


mockResponse =
    Http.GoodStatus_ <metadata> <body>


sendRequestWithMockedResponse =
    Http.get
        { url = "https://fakeurl.com"
        , expect = Http.Mock.expectString mockResponse MyResponseHandler
        }

Again, your update logic should not change, and it doesn't matter what type of request you make - the response is discarded and replaced with the mocked response.

When using this module, it would be a good idea to store all your mock responses in a separate file!

Mock

The API is designed so that usage of this module is almost identical to using elm/http. Simply specify exactly what you want the response to be - everything else looks the same.

The Result is identical to the ones in elm/http. You can use the Transform functions in Detailed if you'd like the detailed responses.