Return codes.InvalidArgument to rather return HTTP 400 instead of HTTP 500

examples/clients/echo/EchoServiceApi.go

@@ -143,3 +143,64 @@ func (a EchoServiceApi) EchoBody (body ExamplepbSimpleMessage) (ExamplepbSimpleM
 
   return *successPayload, err
 }
+/**
+ * Echo method receives a simple message and returns it.
+ * The message posted as the id parameter will also be\nreturned.
+ * @param id 
+ * @param num 
+ * @return ExamplepbSimpleMessage
+ */
+//func (a EchoServiceApi) Echo_1 (id string, num string) (ExamplepbSimpleMessage, error) {
+func (a EchoServiceApi) Echo_1 (id string, num string) (ExamplepbSimpleMessage, error) {
+
+    _sling := sling.New().Get(a.basePath)
+
+    // create path and map variables
+    path := "/v1/example/echo/{id}/{num}"
+    path = strings.Replace(path, "{" + "id" + "}", fmt.Sprintf("%v", id), -1)
+    path = strings.Replace(path, "{" + "num" + "}", fmt.Sprintf("%v", num), -1)
+
+    _sling = _sling.Path(path)
+
+    // accept header
+    accepts := []string { "application/json" }
+    for key := range accepts {
+        _sling = _sling.Set("Accept", accepts[key])
+        break // only use the first Accept
+    }
+
+
+  var successPayload = new(ExamplepbSimpleMessage)
+
+  // We use this map (below) so that any arbitrary error JSON can be handled.
+  // FIXME: This is in the absence of this Go generator honoring the non-2xx
+  // response (error) models, which needs to be implemented at some point.
+  var failurePayload map[string]interface{}
+
+  httpResponse, err := _sling.Receive(successPayload, &failurePayload)
+
+  if err == nil {
+    // err == nil only means that there wasn't a sub-application-layer error (e.g. no network error)
+    if failurePayload != nil {
+      // If the failurePayload is present, there likely was some kind of non-2xx status
+      // returned (and a JSON payload error present)
+      var str []byte
+      str, err = json.Marshal(failurePayload)
+      if err == nil { // For safety, check for an error marshalling... probably superfluous
+        // This will return the JSON error body as a string
+        err = errors.New(string(str))
+      }
+  } else {
+    // So, there was no network-type error, and nothing in the failure payload,
+    // but we should still check the status code
+    if httpResponse == nil {
+      // This should never happen...
+      err = errors.New("No HTTP Response received.")
+    } else if code := httpResponse.StatusCode; 200 > code || code > 299 {
+        err = errors.New("HTTP Error: " + string(httpResponse.StatusCode))
+      }
+    }
+  }
+
+  return *successPayload, err
+}

examples/clients/echo/ExamplepbSimpleMessage.go

@@ -5,5 +5,6 @@ import (
 
 type ExamplepbSimpleMessage struct {
     Id  string  `json:"id,omitempty"`
+    Num  string  `json:"num,omitempty"`
 
 }