Send authorization headers when calling Swarming backend.

appengine/swarming/swarming_bot/config/bot_config.py

 # coding: utf-8
 # Copyright 2013 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 file is meant to be overriden by the server's specific copy.
 
 You can upload a new version via /restricted/upload/bot_config.
 
 There's 3 types of functions in this file:
@@ skipping 22 matching lines @@
 
   The dimensions are what are used to select the bot that can run each task.
 
   The bot id will be automatically selected based on the hostname with
   os_utilities.get_dimensions(). If you want something more special, specify it
   in your bot_config.py and override the item 'id'.
 
   See https://code.google.com/p/swarming/wiki/SwarmingMagicValues.
 
   Arguments:
-  - botobj: bot.Bot instance or None.
+  - bot: bot.Bot instance or None.
   """
   return os_utilities.get_dimensions()
 
 
 def get_state(bot):
   """Returns dict with a state of the bot reported to the server with each poll.
 
   It is only for dynamic state that changes while bot is running for information
   for the sysadmins.
 
   The server can not use this state for immediate scheduling purposes (use
   'dimensions' for that), but it can use it for maintenance and bookkeeping
   tasks.
 
   See https://code.google.com/p/swarming/wiki/SwarmingMagicValues.
 
   Arguments:
-  - botobj: bot.Bot instance or None.
+  - bot: bot.Bot instance or None.
   """
   return os_utilities.get_state()
 
 
+def get_authentication_headers(bot):
+  """Returns authentication headers and their expiration time.
+
+  The returned headers will be passed with each HTTP request to the Swarming
+  server (and only Swarming server). The bot will use the returned headers until
+  they are close to expiration (usually 6 min, see AUTH_HEADERS_EXPIRATION_SEC
+  in remote_client.py), and then it'll attempt to refresh them by calling
+  get_authentication_headers again.
+
+  Can be used to implement per-bot authentication. If no headers are returned,
+  the server will use only IP whitelist for bot authentication.
+
+  May be called by different threads, but never concurrently.
+
+  Arguments:
+  - bot: bot.Bot instance.
+
+  Returns:
+    Tuple (dict with headers or None, unix timestamp of when they expire).
+  """
+  return (None, None)
+
+
 ### Hooks
 
 
 def on_bot_shutdown(bot):
   """Hook function called when the bot shuts down, usually rebooting.
 
   It's a good time to do other kinds of cleanup.
 
   Arguments:
   - bot: bot.Bot instance.
@@ skipping 52 matching lines @@
 def setup_bot(bot):
   """Does one time initialization for this bot.
 
   Returns True if it's fine to start the bot right away. Otherwise, the calling
   script should exit.
 
   Example: making this script starts automatically on user login via
   os_utilities.set_auto_startup_win() or os_utilities.set_auto_startup_osx().
   """
   return True