bleep bloop

testrig/util.go

@@ -0,0 +1,48 @@
+package testrig
+
+import (
+	"bytes"
+	"io"
+	"mime/multipart"
+	"os"
+)
+
+// CreateMultipartFormData is a handy function for taking a fieldname and a filename, and creating a multipart form bytes buffer
+// with the file contents set in the given fieldname. The extraFields param can be used to add extra FormFields to the request, as necessary.
+// The returned bytes.Buffer b can be used like so:
+// 	httptest.NewRequest(http.MethodPost, "https://example.org/whateverpath", bytes.NewReader(b.Bytes()))
+// The returned *multipart.Writer w can be used to set the content type of the request, like so:
+// 	req.Header.Set("Content-Type", w.FormDataContentType())
+func CreateMultipartFormData(fieldName string, fileName string, extraFields map[string]string) (bytes.Buffer, *multipart.Writer, error) {
+	var b bytes.Buffer
+	var err error
+	w := multipart.NewWriter(&b)
+	var fw io.Writer
+	file, err := os.Open(fileName)
+	if err != nil {
+		return b, nil, err
+	}
+	if fw, err = w.CreateFormFile(fieldName, file.Name()); err != nil {
+		return b, nil, err
+	}
+	if _, err = io.Copy(fw, file); err != nil {
+		return b, nil, err
+	}
+
+	if extraFields != nil {
+		for k, v := range extraFields {
+			f, err := w.CreateFormField(k)
+			if err != nil {
+				return b, nil, err
+			}
+			if _, err := io.Copy(f, bytes.NewBufferString(v)); err != nil {
+				return b, nil, err
+			}
+		}
+	}
+
+	if err := w.Close(); err != nil {
+		return b, nil, err
+	}
+	return b, w, nil
+}