apitest

A simple and extensible behavioural testing library. Supports mocking external http calls and renders sequence diagrams on completion.

In behavioural tests the internal structure of the app is not known by the tests. Data is input to the system and the outputs are expected to meet certain conditions.

Join the conversation at #apitest on https://gophers.slack.com.

Logo by @egonelbre

Documentation

Please visit https://apitest.dev for the latest documentation.

Installation

go get -u github.com/steinfletcher/apitest

Examples

Framework and library integration examples

Example	Comment
gin	popular martini-like web framework
gorilla	the gorilla web toolkit
iris	iris web framework
echo	High performance, extensible, minimalist Go web framework
fiber	Express inspired web framework written in Go
httprouter	High performance HTTP request router that scales well
mocks	example mocking out external http calls
sequence diagrams	generate sequence diagrams from tests. See the demo

Companion libraries

Library	Comment
JSONPath	JSONPath assertion addons
CSS Selectors	CSS selector assertion addons
PlantUML	Export sequence diagrams as plantUML
DynamoDB	Add DynamoDB interactions to sequence diagrams

Credits

This library was influenced by the following software packages:

• YatSpec for creating sequence diagrams from tests
• MockMVC and superagent for the concept and behavioural testing approach
• Gock for the approach to mocking HTTP services in Go
• Baloo for API design

Credit to testify which is this libraries' only dependency.

Code snippets

JSON body matcher

func TestApi(t *testing.T) {
	apitest.New().
		Handler(handler).
		Get("/user/1234").
		Expect(t).
		Body(`{"id": "1234", "name": "Tate"}`).
		Status(http.StatusCreated).
		End()
}

JSONPath

For asserting on parts of the response body JSONPath may be used. A separate module must be installed which provides these assertions - go get -u github.com/steinfletcher/apitest-jsonpath. This is packaged separately to keep this library dependency free.

Given the response is {"a": 12345, "b": [{"key": "c", "value": "result"}]}

func TestApi(t *testing.T) {
	apitest.New().
		Handler(handler).
		Get("/hello").
		Expect(t).
		Assert(jsonpath.Contains(`$.b[? @.key=="c"].value`, "result")).
		End()
}

and jsonpath.Equals checks for value equality

func TestApi(t *testing.T) {
	apitest.New(handler).
		Get("/hello").
		Expect(t).
		Assert(jsonpath.Equal(`$.a`, float64(12345))).
		End()
}

Custom assert functions

func TestApi(t *testing.T) {
	apitest.New().
		Handler(handler).
		Get("/hello").
		Expect(t).
		Assert(func(res *http.Response, req *http.Request) {
			assert.Equal(t, http.StatusOK, res.StatusCode)
		}).
		End()
}

Assert cookies

func TestApi(t *testing.T) {
	apitest.New().
		Handler(handler).
		Patch("/hello").
		Expect(t).
		Status(http.StatusOK).
		Cookies(apitest.Cookie"ABC").Value("12345")).
		CookiePresent("Session-Token").
		CookieNotPresent("XXX").
		Cookies(
			apitest.Cookie("ABC").Value("12345"),
			apitest.Cookie("DEF").Value("67890"),
		).
		End()
}

Assert headers

func TestApi(t *testing.T) {
	apitest.New().
		Handler(handler).
		Get("/hello").
		Expect(t).
		Status(http.StatusOK).
		Headers(map[string]string{"ABC": "12345"}).
		End()
}

Mocking external http calls

var getUser = apitest.NewMock().
	Get("/user/12345").
	RespondWith().
	Body(`{"name": "jon", "id": "1234"}`).
	Status(http.StatusOK).
	End()

var getPreferences = apitest.NewMock().
	Get("/preferences/12345").
	RespondWith().
	Body(`{"is_contactable": true}`).
	Status(http.StatusOK).
	End()

func TestApi(t *testing.T) {
	apitest.New().
		Mocks(getUser, getPreferences).
		Handler(handler).
		Get("/hello").
		Expect(t).
		Status(http.StatusOK).
		Body(`{"name": "jon", "id": "1234"}`).
		End()
}

Generating sequence diagrams from tests

func TestApi(t *testing.T) {
	apitest.New().
		Report(apitest.SequenceDiagram()).
		Mocks(getUser, getPreferences).
		Handler(handler).
		Get("/hello").
		Expect(t).
		Status(http.StatusOK).
		Body(`{"name": "jon", "id": "1234"}`).
		End()
}

It is possible to override the default storage location by passing the formatter instance Report(apitest.NewSequenceDiagramFormatter(".sequence-diagrams")). You can bring your own formatter too if you want to produce custom output. By default a sequence diagram is rendered on a html page. See the demo

Debugging http requests and responses generated by api test and any mocks

func TestApi(t *testing.T) {
	apitest.New().
		Debug().
		Handler(handler).
		Get("/hello").
		Expect(t).
		Status(http.StatusOK).
		End()
}

Provide basic auth in the request

func TestApi(t *testing.T) {
	apitest.New().
		Handler(handler).
		Get("/hello").
		BasicAuth("username", "password").
		Expect(t).
		Status(http.StatusOK).
		End()
}

Provide cookies in the request

func TestApi(t *testing.T) {
	apitest.New().
		Handler(handler).
		Get("/hello").
		Cookies(apitest.Cookie("ABC").Value("12345")).
		Expect(t).
		Status(http.StatusOK).
		End()
}

Provide headers in the request

func TestApi(t *testing.T) {
	apitest.New().
		Handler(handler).
		Delete("/hello").
		Headers(map[string]string{"My-Header": "12345"}).
		Expect(t).
		Status(http.StatusOK).
		End()
}

Provide query parameters in the request

Query, QueryParams and QueryCollection can all be used in combination

func TestApi(t *testing.T) {
	apitest.New().
		Handler(handler).
		Get("/hello").
		QueryParams(map[string]string{"a": "1", "b": "2"}).
		Query("c", "d").
		Expect(t).
		Status(http.StatusOK).
		End()
}

Providing {"a": {"b", "c", "d"} results in parameters encoded as a=b&a=c&a=d. QueryCollection can be used in combination with Query

func TestApi(t *testing.T) {
	apitest.New().
		Handler(handler).
		Get("/hello").
		QueryCollection(map[string][]string{"a": {"b", "c", "d"}}).
		Expect(t).
		Status(http.StatusOK).
		End()
}

Provide a url encoded form body in the request

func TestApi(t *testing.T) {
	apitest.New().
		Handler(handler).
		Post("/hello").
		FormData("a", "1").
		FormData("b", "2").
		FormData("b", "3").
		FormData("c", "4", "5", "6").
		Expect(t).
		Status(http.StatusOK).
		End()
}

Capture the request and response data

func TestApi(t *testing.T) {
	apitest.New().
		Observe(func(res *http.Response, req *http.Request, apiTest *apitest.APITest) {
			// do something with res and req
		}).
		Handler(handler).
		Get("/hello").
		Expect(t).
		Status(http.StatusOK).
		End()
}

Intercept the request

This is useful for mutating the request before it is sent to the system under test.

func TestApi(t *testing.T) {
	apitest.New().
		Handler(handler).
		Intercept(func(req *http.Request) {
			req.URL.RawQuery = "a[]=xxx&a[]=yyy"
		}).
		Get("/hello").
		Expect(t).
		Status(http.StatusOK).
		End()
}

Contributing

View the contributing guide.