Echo: How to test a handler that return 404 ?

[remylab]

Description

My handler return a 404, but I cannot test the status code returned as the code does not reach my custom ErrorHandler.

Is there any way I can test the actuel status code in my test ?

I would like to test something like that

assert.Equal(t, http.StatusNotFound, rec.Code)

The handler :

func  (h *Handler)Ipsum(c echo.Context) error {

    ipsumMap, err := h.Dbm.GetIpsum( c.Param("uri") )

    // return 404 when there is not match in the DB
    if ( err != nil ) {
        return echo.NewHTTPError(http.StatusNotFound, err.Error())
    }

The test :

func TestIpsum(t *testing.T) {
    dbm, _ := db.NewSqliteManager("./TestIpsum.db")
    defer db.AfterDbTest(dbm,"./TestIpsum.db")()

    test.LoadTestData("./TestIpsum.db","./app_test.TestIpsum.sql")

    h = &Handler{dbm}

    e, req, rec := test.GetEcho(), new(http.Request), httptest.NewRecorder()
    c := e.NewContext(standard.NewRequest(req, e.Logger()), standard.NewResponse(rec, e.Logger()))

    c.SetPath("/:uri")
    c.SetParamNames("uri")
    c.SetParamValues("i-dont-exist")

    assert.Error(t, h.Ipsum(c))
}

Custom ErrorHandler

func ErrorHandler(err error, c echo.Context) {
    code := http.StatusInternalServerError
    msg := http.StatusText(code)
    he, ok := err.(*echo.HTTPError)
    if ok {

        code = he.Code
        msg = he.Message
        fmt.Printf("ErrorHandler msg :%v for URI =%v \n",msg, c.Request().URI())
        switch code {
        case http.StatusNotFound:
            c.Render(code, "404","")
        default:
            c.Render(code, "404",msg)
        }
    }
}

[vishr]

You response is recorded in rec so assert.Equal(t, http. StatusNotFound, rec.Code). From https://echo.labstack.com/guide/testing

[remylab]

Unfortunately I tried it, and status is 200, rec.Body = "", I don't reach the ErrorHandler (I've put printf in there).

Also, I'm sure the return echo.NewHTTPError(http.StatusNotFound, err.Error()) is reached as I get the err back in the test.

[vishr]

Custom error handler only plays with real request. Are you able to test your handler (standalone) for 404 code?

[remylab]

What do you mean standalone ? I thought this one was :+1:

func TestIpsum(t *testing.T) {
    dbm, _ := db.NewSqliteManager("./TestIpsum.db")
    defer db.AfterDbTest(dbm,"./TestIpsum.db")()

    test.LoadTestData("./TestIpsum.db","./app_test.TestIpsum.sql")

    h = &Handler{dbm}

    e, req, rec := test.GetEcho(), new(http.Request), httptest.NewRecorder()
    c := e.NewContext(standard.NewRequest(req, e.Logger()), standard.NewResponse(rec, e.Logger()))

    c.SetPath("/:uri")
    c.SetParamNames("uri")
    c.SetParamValues("i-dont-exist")

    assert.Error(t, h.Ipsum(c))
}

In the test above the recorded status is 200 , even if

return echo.NewHTTPError(http.StatusNotFound, err.Error())

is executed

[vishr]

For 404 your handler is just returning an error, rec will be filled only if it writes to the response. You should test for error like he, ok := err.(*echo.HTTPError) and check status code in he.

[remylab]

Make sense ! thank you so much , code below works

    err := h.Ipsum(c)
    if( assert.NotNil(t,err) ){
        he, ok := err.(*echo.HTTPError)
        if ok {
            assert.Equal(t, http.StatusNotFound, he.Code)
        } 
    }

[albttx]

Could this be added to the documentation ?

[DannyHinshaw]

Could this be added to the documentation ?

Yea, that is not at all clear from the documentation. I definitely expected to use the rec object to check errors as well.