Want to add a FormFile in unit test Golang - go

Question

I want to test a httpRequest with a json body and a test file.
I don't know how to add the created test file to the request beside body json.
body := strings.NewReader(URLTest.RequestBody)
request, err := http.NewRequest(URLTest.MethodType, "localhost:"+string(listeningPort)+URLTest.URL, body)
if err != nil {
t.Fatalf("HTTP NOT WORKING")
}
fileBuffer := new(bytes.Buffer)
mpWriter := multipart.NewWriter(fileBuffer)
fileWriter, err := mpWriter.CreateFormFile("file", "testfile.pdf")
if err != nil {
t.Fatalf(err.Error())
}
file, err := os.Open("testfile.pdf")
if err != nil {
t.Fatalf(err.Error())
}
defer file.Close()
_, err = io.Copy(fileWriter, file)
if err != nil {
t.Fatalf(err.Error())
}
rec := httptest.NewRecorder()
UploadFiles(rec, request, nil)
response := rec.Result()
if response.StatusCode != URLTest.ExpectedStatusCode {
t.Errorf(URLTest.URL + " status mismatch")
}
responseBody, err := ioutil.ReadAll(response.Body)
defer response.Body.Close()
if err != nil {
t.Errorf(URLTest.URL + " cant read response")
} else {
if strings.TrimSpace(string(responseBody)) != URLTest.ExpectedResponseBody {
t.Errorf(URLTest.URL + " response mismatch - have: " + string(responseBody) + " want: " + URLTest.ExpectedResponseBody)
}
}
}
Can I add file as a value like request.FormFile.Add(...) or something?

Answer 1

Regarding your question about how to send a file in an HTTP request with Go, here's some sample code.
And you will need the mime/multipart package to build the form.
package main
import (
"bytes"
"fmt"
"io"
"mime/multipart"
"net/http"
"net/http/httptest"
"net/http/httputil"
"os"
"strings"
)
func main() {
var client *http.Client
var remoteURL string
{
//setup a mocked http client.
ts := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
b, err := httputil.DumpRequest(r, true)
if err != nil {
panic(err)
}
fmt.Printf("%s", b)
}))
defer ts.Close()
client = ts.Client()
remoteURL = ts.URL
}
//prepare the reader instances to encode
values := map[string]io.Reader{
"file": mustOpen("main.go"), // lets assume its this file
"other": strings.NewReader("hello world!"),
}
err := Upload(client, remoteURL, values)
if err != nil {
panic(err)
}
}
func Upload(client *http.Client, url string, values map[string]io.Reader) (err error) {
// Prepare a form that you will submit to that URL.
var b bytes.Buffer
w := multipart.NewWriter(&b)
for key, r := range values {
var fw io.Writer
if x, ok := r.(io.Closer); ok {
defer x.Close()
}
// Add an image file
if x, ok := r.(*os.File); ok {
if fw, err = w.CreateFormFile(key, x.Name()); err != nil {
return
}
} else {
// Add other fields
if fw, err = w.CreateFormField(key); err != nil {
return
}
}
if _, err = io.Copy(fw, r); err != nil {
return err
}
}
// Don't forget to close the multipart writer.
// If you don't close it, your request will be missing the terminating boundary.
w.Close()
// Now that you have a form, you can submit it to your handler.
req, err := http.NewRequest("POST", url, &b)
if err != nil {
return
}
// Don't forget to set the content type, this will contain the boundary.
req.Header.Set("Content-Type", w.FormDataContentType())
// Submit the request
res, err := client.Do(req)
if err != nil {
return
}
// Check the response
if res.StatusCode != http.StatusOK {
err = fmt.Errorf("bad status: %s", res.Status)
}
return
}
Hope you can use this in your unit test