eager loading optimization

peterberwind · peterberwind · commit d1617f58a592 · 2016-09-28T01:52:48.000-04:00
diff --git a/public/index.html b/public/index.html
@@ -46,6 +46,13 @@
           setInterval(this.loadCommentsFromServer, this.props.pollInterval);
         },
         handleCommentSubmit: function(comment) {
+          var comments = this.state.data;
+          // Optimistically set an id on the new comment. It will be replaced by an
+          // id generated by the server. In a production application you would likely
+          // not use Date.now() for this and would have a more robust system in place.
+          comment.id = Date.now();
+          var newComments = comments.concat([comment]);
+          this.setState({data: newComments});
           $.ajax({
             url: this.props.url,
             dataType: 'json',
@@ -55,6 +62,7 @@
               this.setState({data: data});
             }.bind(this),
             error: function(xhr, status, err) {
+              this.setState({data: comments});
               console.error(this.props.url, status, err.toString());
             }.bind(this)
           });
