How to write a test using httprouter
I am writing tests for a simple REST service in GoLang. But since I am using julienschmidt / httprouter as my routing library. I am struggling on how to write a test.
main.go
package main
func main() {
router := httprouter.New()
bookController := controllers.NewBookController()
router.GET("/book/:id", bookController.GetBook)
http.ListenAndServe(":8080", router)
}
controllers
package controllers
type BookController struct {}
func NewBookController *BookController {
return &BookController()
}
func (bc BookController) GetBook(w http.ResponseWriter, r *http.Request, p httprouter.Params) {
fmt.Fprintf(w,"%s", p)
}
My question is how to check this while GetBook is neither HttpHandler nor HttpHandle
If I use a traditional handler, the test is as simple as this
func TestGetBook(t *testing.T) {
req, _ := http.NewRequest("GET", "/book/sampleid", nil)
rr := httptest.NewRecorder()
handler := controllers.NewBookController().GetBook
handler.ServeHTTP(rr,req)
if status := rr.code; status != http.StatusOK {
t.Errorf("Wrong status")
}
}
The problem is that httprouter is not a handler or handlefunc. So I'm stuck now
Just start a new router for each test, and then register a handler in the test, and then pass the test request to the router, not the handler, so the router can parse the path parameters and pass them on to the handler.
func TestGetBook(t *testing.T) {
handler := controllers.NewBookController()
router := httprouter.New()
router.GET("/book/:id", handler.GetBook)
req, _ := http.NewRequest("GET", "/book/sampleid", nil)
rr := httptest.NewRecorder()
router.ServeHTTP(rr, req)
if status := rr.Code; status != http.StatusOK {
t.Errorf("Wrong status")
}
}
You need to wrap the handler so that it can be accessed like http.HandlerFunc
:
func TestGetBook(t *testing.T) {
req, _ := http.NewRequest("GET", "/book/sampleid", nil)
rr := httptest.NewRecorder()
handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
controllers.NewBookController().GetBook(w, r, httprouter.Params{})
})
handler.ServeHTTP(rr,req)
if status := rr.code; status != http.StatusOK {
t.Errorf("Wrong status")
}
}
If your handler requires parameters, you will either have to manually parse it from the request, or simply supply it as the third argument.
u can try this without ServeHTTP
func TestGetBook(t *testing.T) {
req := httptest.NewRequest("GET", "http://example.com/foo", nil)
w := httptest.NewRecorder()
controllers.NewBookController().GetBook(w, req, []httprouter.Param{{Key: "id", Value: "101"}})
resp := w.Result()
body, _ := ioutil.ReadAll(resp.Body)
t.Log(resp.StatusCode)
t.Log(resp.Header.Get("Content-Type"))
t.Log(string(body))
}
here is another good blog and related working code for that:
https://medium.com/@gauravsingharoy/build-your-first-api-server-with-httprouter-in-golang-732b7b01f6ab
https://github.com/gsingharoy/httprouter-tutorial/blob/master/part4/handlers_test.go