From ec04cb8346e7ea5309963f43bf16622e13f94100 Mon Sep 17 00:00:00 2001
From: Sithum Sathsara <89584440+SithumSathsaras@users.noreply.github.com>
Date: Fri, 18 Oct 2024 02:27:30 -0400
Subject: [PATCH] Fixed Issue: #2195 500 error when sending empty JSON payload
 to GraphQL server

---
 pkg/metrics/prometheus.go | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/pkg/metrics/prometheus.go b/pkg/metrics/prometheus.go
index 7b1e939618..edc762a593 100644
--- a/pkg/metrics/prometheus.go
+++ b/pkg/metrics/prometheus.go
@@ -278,6 +278,7 @@ func (pc *prometheusCollector) MeasureGraphQLResponseDuration(next http.Handler)
 
 		// Create a copy of the request body
 		body, err := io.ReadAll(r.Body)
+
 		if err != nil {
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return
@@ -292,6 +293,11 @@ func (pc *prometheusCollector) MeasureGraphQLResponseDuration(next http.Handler)
 		var graphqlRequest struct {
 			OperationName string `json:"operationName"`
 		}
+		if !json.Valid(bodyCopy) { // Check if the body is valid JSON
+			err_msg := fmt.Sprintf("Provided input json couldn't be parsed. likely it was empty or was wrongly structured; error message: %v", err.Error())
+			http.Error(w, err_msg, http.StatusBadRequest)
+			return
+		}
 		if err := json.Unmarshal(bodyCopy, &graphqlRequest); err != nil {
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return