config_service: Added revision and timestamp to config-set-cards and config-set pages

appengine/config_service/ui/common/common-behaviors.html

+<!--
+  Copyright 2017 The LUCI Authors. All rights reserved.
+  Use of this source code is governed under the Apache License, Version 2.0
+  that can be found in the LICENSE file.
+
+  It contains the definition of the following Behaviors:
+
+    ConfigUIBehaviors.CommonBehavior
+
+  To use it, include
+      behaviors: [ConfigUIBehaviors.CommonBehavior]
+  in the creation of any Polymer element.
+
+  ConfigUIBehaviors.CommonBehavior contains shared methods to ease
+  templating, such _isEmpty() and _not(), as well as general utility methods
+  such as _formatDate and _getTimestamp.
+ -->
+
+ <script>
+  window.ConfigUIBehaviors = window.ConfigUIBehaviors || {};
+  (function(){
+    // This behavior wraps up all the shared config UI functionality.
+    ConfigUIBehaviors.CommonBehavior = {

[Sergey Berezin, 2017/07/31 20:21:18]

Could you add unittests for these functions?

[cwpayton, 2017/07/31 23:40:52]

Done.

+
+      _formatDate: function(timestamp) {
+        var date = new Date(timestamp / 1000);
+        var month = date.getMonth() + 1;
+        if (month < 10) {
+          month = "0" + month;
+        }
+        var day = date.getDate();
+        if (day < 10) {
+          day = "0" + day;
+        }
+        var hours = date.getHours();
+        if (hours < 10) {
+          hours = "0" + hours;
+        }
+        var minutes = date.getMinutes();
+        if (minutes < 10) {
+          minutes = "0" + minutes;
+        }
+        return month + "/" + day + "/" + date.getFullYear() +
+            " " + hours + ":" + minutes;

[Sergey Berezin, 2017/07/31 20:21:18]

Why not just use date.toString()? In particular, it prints the timezone (local
by default), so the timestamp is not ambiguous.

Also consider formatting it as "x minutes/hours/days/... ago" with a tooltip
showing the full timestamp (see comments in other files).

[cwpayton, 2017/07/31 23:40:52]

Done.

+      },
+
+      _frontPageIsActive: function() {
+        if (this.frontPageIsActive === false) {
+          this.isLoading = true;
+          if (!this.initialized) {
+            document.addEventListener('fetch-configs', function() {
+              this.$.requestConfigs.generateRequest();
+            }.bind(this));
+          } else {
+            this.$.requestConfigs.generateRequest();
+          }
+        }
+      },
+
+      _getTimestamp: function(lastImportAttempt, revision) {
+        if (lastImportAttempt && lastImportAttempt.success) {
+          return this._formatDate(lastImportAttempt.revision.timestamp);
+        } else if (revision && revision.timestamp) {
+          return this._formatDate(revision.timestamp);
+        } else {
+          return "Not Found"
+        }
+      },
+
+      _getRevision: function(revision) {
+        if (revision) {
+          return revision.id;
+        } else {
+          return "Not Found"
+        }
+      },
+
+      _isEmpty: function(list) {
+        return list.length === 0;
+      },
+
+      _not: function(a) {
+        return !a;
+      },
+    };
+  })();
+</script>