1 files changed, 56 insertions, 0 deletions
diff --git a/devtools/client/netmonitor/src/components/messages/ColumnTime.js b/devtools/client/netmonitor/src/components/messages/ColumnTime.js
new file mode 100644
index 0000000000..594a6b705b
--- /dev/null
+++ b/devtools/client/netmonitor/src/components/messages/ColumnTime.js
@@ -0,0 +1,56 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const {
+  Component,
+} = require("resource://devtools/client/shared/vendor/react.js");
+const dom = require("resource://devtools/client/shared/vendor/react-dom-factories.js");
+const PropTypes = require("resource://devtools/client/shared/vendor/react-prop-types.js");
+
+/**
+ * Renders the "Time" column of a message.
+ */
+class ColumnTime extends Component {
+  static get propTypes() {
+    return {
+      item: PropTypes.object.isRequired,
+    };
+  }
+
+  shouldComponentUpdate(nextProps) {
+    return (
+      this.props.item.type !== nextProps.item.type ||
+      this.props.item.timeStamp !== nextProps.item.timeStamp
+    );
+  }
+
+  /**
+   * Format a DOMHighResTimeStamp (in microseconds) as HH:mm:ss.SSS
+   * @param {number} highResTimeStamp
+   */
+  formatTime(highResTimeStamp) {
+    const date = new Date(highResTimeStamp / 1000);
+    const hh = date.getHours().toString().padStart(2, "0");
+    const mm = date.getMinutes().toString().padStart(2, "0");
+    const ss = date.getSeconds().toString().padStart(2, "0");
+    const mmm = date.getMilliseconds().toString().padStart(3, "0");
+    return `${hh}:${mm}:${ss}.${mmm}`;
+  }
+
+  render() {
+    const label = this.formatTime(this.props.item.timeStamp);
+
+    return dom.td(
+      {
+        className: "message-list-column message-list-time",
+        title: label,
+      },
+      label
+    );
+  }
+}
+
+module.exports = ColumnTime;