Fix on-job-complete request not having json body (#2409)

Author: RobertLucian

pkg/enqueuer/enqueuer.go

@@ -78,6 +78,10 @@ type JobSubmission struct {
 	DelimitedFiles *DelimitedFiles `json:"delimited_files"`
 }
 
+type onJobCompleteRequestBody struct {
+	Message string `json:"message"`
+}
+
 func randomMessageID() string {
 	return random.String(40) // maximum is 80 (for sqs.SendMessageBatchRequestEntry.Id) but this ID may show up in a user error message
 }
@@ -127,10 +131,17 @@ func (e *Enqueuer) Enqueue() (int, error) {
 		}
 	}
 
+	onJobCompleteBodyBytes, err := json.Marshal(onJobCompleteRequestBody{
+		Message: "job_complete",
+	})
+	if err != nil {
+		return 0, err
+	}
+
 	randomID := randomMessageID()
 	_, err = e.aws.SQS().SendMessage(&sqs.SendMessageInput{
 		QueueUrl:               aws.String(e.queueURL),
-		MessageBody:            aws.String("\"job_complete\""),
+		MessageBody:            aws.String(string(onJobCompleteBodyBytes)),
 		MessageDeduplicationId: aws.String(randomID), // prevent content based deduping
 		MessageGroupId:         aws.String(randomID), // aws recommends message group id per message to improve chances of exactly-once
 		MessageAttributes: map[string]*sqs.MessageAttributeValue{