Return error from function posting to APM server (#30)

Author: estolfo

apm-lambda-extension/extension/apm_server.go

@@ -11,7 +11,7 @@ import (
 // todo: can this be a streaming or streaming style call that keeps the
 //       connection open across invocations?
 // func PostToApmServer(postBody []byte, apmServerEndpoint string, apmServerSecretToken string) {
-func PostToApmServer(postBody []byte, config *extensionConfig) {
+func PostToApmServer(postBody []byte, config *extensionConfig) error {
 	var compressedBytes bytes.Buffer
 	w := gzip.NewWriter(&compressedBytes)
 	w.Write(postBody)
@@ -34,7 +34,7 @@ func PostToApmServer(postBody []byte, config *extensionConfig) {
 	}
 	resp, err := client.Do(req)
 	if err != nil {
-		log.Fatalf("An Error Occured calling client.Do %v", err)
+		return err
 	}
 
 	//Read the response body
@@ -49,4 +49,6 @@ func PostToApmServer(postBody []byte, config *extensionConfig) {
 	sb := string(body)
 	log.Printf("Response Headers: %v\n", resp.Header)
 	log.Printf("Response Body: %v\n", sb)
+
+	return nil
 }

apm-lambda-extension/extension/process_events.go

@@ -14,9 +14,12 @@ func FlushAPMData(dataChannel chan []byte, config *extensionConfig) {
 	log.Println("Checking for agent data")
 	for {
 		select {
-		case agentBytes := <-dataChannel:
+		case agentData := <-dataChannel:
 			log.Println("Received bytes from data channel")
-			PostToApmServer(agentBytes, config)
+			err := PostToApmServer(agentData, config)
+			if err != nil {
+				log.Printf("Error sending to APM server: %v", err)
+			}
 		default:
 			log.Println("No more agent data")
 			return

apm-lambda-extension/extension/route_handlers.go

@@ -10,7 +10,7 @@ func handleIntakeV2Events(handler *serverHandler, w http.ResponseWriter, r *http
 	if nil != err {
 		log.Println("could not get bytes from body")
 	} else {
-		log.Println("Receiving bytes from request")
+		log.Println("Receiving bytes from agent request")
 		handler.data <- bodyBytes
 	}
 	w.WriteHeader(http.StatusAccepted)

apm-lambda-extension/main.go

@@ -82,7 +82,7 @@ func main() {
 				log.Println("Exiting")
 				return
 			}
-			log.Printf("Received event: %v\n", extension.PrettyPrint(res))
+			log.Printf("Received event: %v\n", extension.PrettyPrint(event))
 
 			// A shutdown event indicates the execution environment is shutting down.
 			// This is usually due to inactivity.
@@ -111,7 +111,10 @@ func main() {
 						log.Println("Function invocation is complete, not receiving any more agent data")
 						return
 					case agentData := <-dataChannel:
-						extension.PostToApmServer(agentData, config)
+						err := extension.PostToApmServer(agentData, config)
+						if err != nil {
+							log.Printf("Error sending to APM server: %v", err)
+						}
 					}
 				}
 			}()