PLT-5379 Fix the error occuring while fetching OG metadata for links which don't exist. (#5308)

api/post.go

@@ -444,6 +444,7 @@ func getOpenGraphMetadata(c *Context, w http.ResponseWriter, r *http.Request) {
 	ogJson, err := og.ToJSON()
 	if err != nil {
 		w.Write([]byte(`{"url": ""}`))
+		return
 	}
 	w.Write(ogJson)
 }

app/post.go

@@ -488,10 +488,10 @@ func GetOpenGraphMetadata(url string) *opengraph.OpenGraph {
 	og := opengraph.NewOpenGraph()
 
 	res, err := http.Get(url)
-	defer CloseBody(res)
 	if err != nil {
 		return og
 	}
+	defer CloseBody(res)
 
 	if err := og.ProcessHTML(res.Body); err != nil {
 		return og