swarming: Remove support for task without 'pool' dimension

appengine/swarming/server/task_request.py

 # coding: utf-8
 # Copyright 2014 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.
 
 """Tasks definition.
 
 Each user request creates a new TaskRequest. The TaskRequest instance saves the
 metadata of the request, e.g. who requested it, when why, etc. It links to the
 actual data of the request in a TaskProperties. The TaskProperties represents
@@ skipping 144 matching lines @@
   # pylint: disable=W0212
   if not value:
     raise datastore_errors.BadValueError(u'%s must be specified' % prop._name)
   _validate_dict_of_strings(prop, value)
   for key, val in value.iteritems():
     if not config.validate_dimension_key(key):
       raise datastore_errors.BadValueError(u'dimension %r isn\'t valid' % key)
     if not config.validate_dimension_value(val):
       raise datastore_errors.BadValueError(
           u'dimension %r:%r isn\'t valid' % (key, val))
-  if u'pool' not in value and u'id' not in value:
-    raise datastore_errors.BadValueError(
-        u'At least one of \'id\' or \'pool\' must be used as %s' % prop._name)
   if len(value) > 64:
     raise datastore_errors.BadValueError(
         '%s can have up to 64 keys' % prop._name)
 
 
 def _validate_env(prop, value):
   _validate_dict_of_strings(prop, value)
   maxlen = 1024
   for k, v in value.iteritems():
     if not k:
@@ skipping 304 matching lines @@
   # May be non-None even if task input is not isolated.
   #
   # Only inputs_ref.isolated or command can be specified.
   inputs_ref = ndb.LocalStructuredProperty(FilesRef)
 
   # CIPD packages to install.
   cipd_input = ndb.LocalStructuredProperty(CipdInput)
 
   # Filter to use to determine the required properties on the bot to run on. For
   # example, Windows or hostname. Encoded as json. Either 'pool' or 'id'
-  # dimension are required (see _validate_dimensions).
+  # dimension are required (see _validate_dimensions and _pre_put_hook).
   dimensions = datastore_utils.DeterministicJsonProperty(
       validator=_validate_dimensions, json_type=dict, indexed=False)
 
   # Environment variables. Encoded as json. Optional.
   env = datastore_utils.DeterministicJsonProperty(
       validator=_validate_env, json_type=dict, indexed=False)
 
   # Maximum duration the bot can take to run this task. It's named hard_timeout
   # in the bot.
   execution_timeout_secs = ndb.IntegerProperty(
@@ skipping 44 matching lines @@
         not self.grace_period_secs and
         not self.io_timeout_secs and
         not self.idempotent and
         not self.outputs and
         not self.has_secret_bytes)
 
   def _pre_put_hook(self):
     super(TaskProperties, self)._pre_put_hook()
     if self.is_terminate:
       # Most values are not valid with a terminate task. self.is_terminate
-      # already check those.
+      # already check those. Terminate task can only use 'id'.
       return
 
+    if u'pool' not in self.dimensions:
+      # Only terminate task may no use 'pool'. Others must specify one.
+      raise datastore_errors.BadValueError(
+          u'\'pool\' must be used as dimensions')
+
     isolated_input = self.inputs_ref and self.inputs_ref.isolated
     if not self.command and not isolated_input:
       raise datastore_errors.BadValueError(
           'use at least one of command or inputs_ref.isolated')
     if self.command and self.extra_args:
       raise datastore_errors.BadValueError(
           'can\'t use both command and extra_args')
     if self.extra_args and not isolated_input:
       raise datastore_errors.BadValueError(
           'extra_args require inputs_ref.isolated')
@@ skipping 444 matching lines @@
   init_new_request(request, allow_high_priority, original_secret_bytes)
   return request
 
 
 def validate_priority(priority):
   """Throws ValueError if priority is not a valid value."""
   if 0 > priority or MAXIMUM_PRIORITY < priority:
     raise datastore_errors.BadValueError(
         'priority (%d) must be between 0 and %d (inclusive)' %
         (priority, MAXIMUM_PRIORITY))