Add bot-page stubs

appengine/swarming/elements/res/imp/botpage/bot-page-data.html

+<!--
+  Copyright 2016 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.
+
+  This in an HTML Import-able file that contains the definition
+  of the following elements:
+
+    <bot-page-data>
+
+  This makes calls authenticated with Oauth 2 to the swarming apis.  It parses

[stephana, 2016/09/01 13:25:39]

Based on our recent discussion about JS conventions, wouldn't this better in JS
as part of the bot-page element or a sub element. 

[kjlubick, 2016/09/01 14:32:29]

The Skia element status-sk originally had everything in one file and it was a
monolithic mess.  Keeping the logic that fetches and parses the data separate
from the display of the data is way easier for me to understand and maintain.

If this element were more simple, I would be more likely to agree, but this
element will not be trivial.  So far (in a future CL), it is about 250 LOC. 

[stephana, 2016/09/01 14:48:35]

Acknowledged.

+  that data into usable data structures.
+
+  Properties:
+    busy: Boolean, if we are fetching any data from the server.
+    bot: Object, The information about the bot. See swarming_rpcs.py#BotInfo
+        for all relevent fields.
+    events: Array<Object>, The most recent events that pertain to this bot.
+        Contains the following fields: "event_type", "message", "ts" (timestamp),

[stephana, 2016/09/01 13:25:39]

If it's easily available, it would be helpful to just paste an example of the
underlying JSON object here.

[kjlubick, 2016/09/01 14:32:29]

I think they are a bit long to inline.  If you run `make run`, the Makefile will
download sample data to inspect.

[stephana, 2016/09/01 14:48:35]

Acknowledged.

+        "quarantined", "version".
+    tasks: Array<Object>, The most recent tasks done by this bot.
+        Contains the following fields: "abandoned_ts", "bot_version", "duration",
+        "failure", "internal_failure", "modified_ts", "name", "started_ts",
+        "state", "task_id", "try_number".
+
+  Methods:
+    request(): Force a fetch of the data. This happens automatically when
+        auth_headers is set or bot_id is changed.
+
+  Events:
+    None.
+-->
+
+
+<link rel="import" href="/res/imp/common/common-behavior.html">
+
+<dom-module id="bot-page-data">
+  <script>
+  (function(){
+
+    Polymer({
+      is: 'bot-page-data',
+
+      behaviors: [
+          SwarmingBehaviors.CommonBehavior,
+      ],
+
+      properties: {
+        // inputs
+        auth_headers: {
+          type: Object,
+        },
+        bot_id: {
+          type: String,
+        },
+
+        // outputs
+        busy: {
+          type: Boolean,
+          computed: "_or(_busy1,_busy2,_busy3)",
+          notify: true,
+        },
+        bot: {
+          type: Object,
+          computed: "_parseBot(_bot)",
+          notify: true,
+        },
+        events: {
+          type: Array,
+          computed: "_parseEvents(_events)",
+          notify: true,
+        },
+        tasks: {
+          type: Array,
+          computed: "_parseTasks(_tasks)",
+          notify: true,
+        },
+
+        // private
+         _busy1: {
+          type: Boolean,
+          value: false
+        },
+        _busy2: {
+          type: Boolean,
+          value: false
+        },
+        _busy3: {
+          type: Boolean,
+          value: false
+        },
+        _bot: {
+          type: Object,
+        },
+        _events: {
+          type: Object,
+        },
+        _tasks: {
+          type: Object,
+        },
+      },
+
+      observers: [
+        "request(auth_headers,bot_id)",
+      ],
+
+      request: function(){
+        if (!this.bot_id || !this.auth_headers) {
+          console.log("bot_id and auth_headers can't be empty");
+          return;
+        }
+        var baseUrl = "/_ah/api/swarming/v1/bot/"+this.bot_id;
+        this._getJsonAsync("_bot", baseUrl + "/get",
+          "_busy1", this.auth_headers);
+        // We limit the fields on these two queries to make them faster.
+        this._getJsonAsync("_events",
+          baseUrl + "/events?fields=items(event_type%2Cmessage%2Cquarantined%2Ctask_id%2Cts%2Cversion)",
+          "_busy2", this.auth_headers);
+        this._getJsonAsync("_tasks",
+          baseUrl + "/tasks?fields=items(abandoned_ts%2Cbot_version%2Ccompleted_ts%2Cduration%2Cexit_code%2Cfailure%2Cinternal_failure%2Cmodified_ts%2Cname%2Cstarted_ts%2Cstate%2Ctask_id%2Ctry_number)",
+          "_busy3", this.auth_headers);
+      },
+
+      _parseBot: function(bot) {
+        if (!bot) {
+          return {};
+        }
+        return bot;
+      },
+
+      _parseEvents: function(events) {
+        if (!events || !events.items) {
+          return [];
+        }
+        return events.items;
+      },
+
+      _parseTasks: function(tasks) {
+        if (!tasks || !tasks.items) {
+          return [];
+        }
+        return tasks.items;
+      }
+
+    });
+  })();
+  </script>
+</dom-module>