fix(api): accept 2xx responses without error

Many of our API endpoints that create objects now return 201 Created
instead of 200 OK. The API implementation here was previously only
accepting http.StatusOK as valid.

With this change, the API handler now accepts 2xx status codes.

Bug: #173

cloudflare.go

@@ -109,15 +109,18 @@ func (api *API) makeRequestWithAuthType(method, uri string, params interface{},
 		return nil, errors.Wrap(err, "could not read response body")
 	}
 
-	switch resp.StatusCode {
-	case http.StatusOK:
-		break
-	case http.StatusUnauthorized:
+	switch {
+	case resp.StatusCode >= http.StatusOK && resp.StatusCode < http.StatusMultipleChoices:
+	case resp.StatusCode == http.StatusUnauthorized:
 		return nil, errors.Errorf("HTTP status %d: invalid credentials", resp.StatusCode)
-	case http.StatusForbidden:
+	case resp.StatusCode == http.StatusForbidden:
 		return nil, errors.Errorf("HTTP status %d: insufficient permissions", resp.StatusCode)
-	case http.StatusServiceUnavailable, http.StatusBadGateway, http.StatusGatewayTimeout,
-		522, 523, 524:
+	case resp.StatusCode == http.StatusServiceUnavailable,
+		resp.StatusCode == http.StatusBadGateway,
+		resp.StatusCode == http.StatusGatewayTimeout,
+		resp.StatusCode == 522,
+		resp.StatusCode == 523,
+		resp.StatusCode == 524:
 		return nil, errors.Errorf("HTTP status %d: service failure", resp.StatusCode)
 	default:
 		var s string

custom_hostname_test.go

@@ -35,6 +35,7 @@ func TestCustomHostname_CreateCustomHostname(t *testing.T) {
 		assert.Equal(t, "POST", r.Method, "Expected method 'POST', got %s", r.Method)
 
 		w.Header().Set("content-type", "application/json")
+		w.WriteHeader(http.StatusCreated)
 		fmt.Fprintf(w, `
 {
   "success": true,