Versatile HTTP mocking made easy in Go that works with any net/http
based stdlib implementation.
Heavily inspired by nock. There is also its Python port, pook.
To get started, take a look to the examples.
- Simple, expressive, fluent API.
- Semantic API DSL for declarative HTTP mock declarations.
- Built-in helpers for easy JSON/XML mocking.
- Supports persistent and volatile TTL-limited mocks.
- Full regular expressions capable HTTP request mock matching.
- Designed for both testing and runtime scenarios.
- Match request by method, URL params, headers and bodies.
- Extensible and pluggable HTTP matching rules.
- Ability to switch between mock and real networking modes.
- Ability to filter/map HTTP requests for accurate mock matching.
- Supports map and filters to handle mocks easily.
- Wide compatible HTTP interceptor using
http.RoundTripper
interface. - Works with any
net/http
compatible client, such as gentleman. - Network timeout/cancelation delay simulation.
- Extensible and hackable API.
- Dependency free.
go get -u github.com/h2non/gock
See godoc reference for detailed API documentation.
- Intercepts any HTTP outgoing request via
http.DefaultTransport
or customhttp.Transport
used by anyhttp.Client
. - Matches outgoing HTTP requests against a pool of defined HTTP mock expectations in FIFO declaration order.
- If at least one mock matches, it will be used in order to compose the mock HTTP response.
- If no mock can be matched, it will resolve the request with an error, unless real networking mode is enable, in which case a real HTTP request will be performed.
Declare your mocks before you start declaring the concrete test logic:
func TestFoo(t *testing.T) {
defer gock.Off() // Flush pending mocks after test execution
gock.New("http://server.com").
Get("/bar").
Reply(200).
JSON(map[string]string{"foo": "bar"})
// Your test code starts here...
}
If you're running concurrent code, be aware that your mocks are declared first to avoid unexpected
race conditions while configuring gock
or intercepting custom HTTP clients.
gock
is not fully thread-safe, but sensible parts are.
Any help making gock
more reliable in this sense is appreciated.
If you're mocking a bunch of mocks in the same test suite, it's recommended to define the more concrete mocks first, and then the generic ones.
This approach usually avoids matching unexpected generic mocks (e.g: specific header, body payload...) instead of the generic ones that performs less complex matches.
In other to minimize potential side effects within your test code, it's a good practice
disabling gock
once you are done with your HTTP testing logic.
A Go idiomatic approach for doing this can be using it in a defer
statement, such as:
func TestGock (t *testing.T) {
defer gock.Off()
// ... my test code goes here
}
You don't need to intercept multiple times the same http.Client
instance.
Just call gock.InterceptClient(client)
once, typically at the beginning of your test scenarios.
NOTE: this is not required is you are using http.DefaultClient
or http.DefaultTransport
.
As a good testing pattern, you should call gock.RestoreClient(client)
after running your test scenario, typically as after clean up hook.
You can also use a defer
statement for doing it, as you do with gock.Off()
, such as:
func TestGock (t *testing.T) {
defer gock.Off()
defer gock.RestoreClient(client)
// ... my test code goes here
}
See examples directory for more featured use cases.
package test
import (
"io/ioutil"
"net/http"
"testing"
"github.com/nbio/st"
"github.com/h2non/gock"
)
func TestSimple(t *testing.T) {
defer gock.Off()
gock.New("http://foo.com").
Get("/bar").
Reply(200).
JSON(map[string]string{"foo": "bar"})
res, err := http.Get("http://foo.com/bar")
st.Expect(t, err, nil)
st.Expect(t, res.StatusCode, 200)
body, _ := ioutil.ReadAll(res.Body)
st.Expect(t, string(body)[:13], `{"foo":"bar"}`)
// Verify that we don't have pending mocks
st.Expect(t, gock.IsDone(), true)
}
package test
import (
"io/ioutil"
"net/http"
"testing"
"github.com/nbio/st"
"github.com/h2non/gock"
)
func TestMatchHeaders(t *testing.T) {
defer gock.Off()
gock.New("http://foo.com").
MatchHeader("Authorization", "^foo bar$").
MatchHeader("API", "1.[0-9]+").
HeaderPresent("Accept").
Reply(200).
BodyString("foo foo")
req, err := http.NewRequest("GET", "http://foo.com", nil)
req.Header.Set("Authorization", "foo bar")
req.Header.Set("API", "1.0")
req.Header.Set("Accept", "text/plain")
res, err := (&http.Client{}).Do(req)
st.Expect(t, err, nil)
st.Expect(t, res.StatusCode, 200)
body, _ := ioutil.ReadAll(res.Body)
st.Expect(t, string(body), "foo foo")
// Verify that we don't have pending mocks
st.Expect(t, gock.IsDone(), true)
}
package test
import (
"io/ioutil"
"net/http"
"testing"
"github.com/nbio/st"
"github.com/h2non/gock"
)
func TestMatchParams(t *testing.T) {
defer gock.Off()
gock.New("http://foo.com").
MatchParam("page", "1").
MatchParam("per_page", "10").
Reply(200).
BodyString("foo foo")
req, err := http.NewRequest("GET", "http://foo.com?page=1&per_page=10", nil)
res, err := (&http.Client{}).Do(req)
st.Expect(t, err, nil)
st.Expect(t, res.StatusCode, 200)
body, _ := ioutil.ReadAll(res.Body)
st.Expect(t, string(body), "foo foo")
// Verify that we don't have pending mocks
st.Expect(t, gock.IsDone(), true)
}
package test
import (
"bytes"
"io/ioutil"
"net/http"
"testing"
"github.com/nbio/st"
"github.com/h2non/gock"
)
func TestMockSimple(t *testing.T) {
defer gock.Off()
gock.New("http://foo.com").
Post("/bar").
MatchType("json").
JSON(map[string]string{"foo": "bar"}).
Reply(201).
JSON(map[string]string{"bar": "foo"})
body := bytes.NewBuffer([]byte(`{"foo":"bar"}`))
res, err := http.Post("http://foo.com/bar", "application/json", body)
st.Expect(t, err, nil)
st.Expect(t, res.StatusCode, 201)
resBody, _ := ioutil.ReadAll(res.Body)
st.Expect(t, string(resBody)[:13], `{"bar":"foo"}`)
// Verify that we don't have pending mocks
st.Expect(t, gock.IsDone(), true)
}
package test
import (
"io/ioutil"
"net/http"
"testing"
"github.com/nbio/st"
"github.com/h2non/gock"
)
func TestClient(t *testing.T) {
defer gock.Off()
gock.New("http://foo.com").
Reply(200).
BodyString("foo foo")
req, err := http.NewRequest("GET", "http://foo.com", nil)
client := &http.Client{Transport: &http.Transport{}}
gock.InterceptClient(client)
res, err := client.Do(req)
st.Expect(t, err, nil)
st.Expect(t, res.StatusCode, 200)
body, _ := ioutil.ReadAll(res.Body)
st.Expect(t, string(body), "foo foo")
// Verify that we don't have pending mocks
st.Expect(t, gock.IsDone(), true)
}
package main
import (
"fmt"
"io/ioutil"
"net/http"
"github.com/h2non/gock"
)
func main() {
defer gock.Off()
defer gock.DisableNetworking()
gock.EnableNetworking()
gock.New("http://httpbin.org").
Get("/get").
Reply(201).
SetHeader("Server", "gock")
res, err := http.Get("http://httpbin.org/get")
if err != nil {
fmt.Errorf("Error: %s", err)
}
// The response status comes from the mock
fmt.Printf("Status: %d\n", res.StatusCode)
// The server header comes from mock as well
fmt.Printf("Server header: %s\n", res.Header.Get("Server"))
// Response body is the original
body, _ := ioutil.ReadAll(res.Body)
fmt.Printf("Body: %s", string(body))
}
package main
import (
"bytes"
"net/http"
"github.com/h2non/gock"
)
func main() {
defer gock.Off()
gock.Observe(gock.DumpRequest)
gock.New("http://foo.com").
Post("/bar").
MatchType("json").
JSON(map[string]string{"foo": "bar"}).
Reply(200)
body := bytes.NewBuffer([]byte(`{"foo":"bar"}`))
http.Post("http://foo.com/bar", "application/json", body)
}
You can easily hack gock
defining custom matcher functions with own matching rules.
See add matcher functions and custom matching layer examples for further details.
MIT - Tomas Aparicio