Modify annotated_run to read factory configs from the slave checkout.

scripts/slave/annotated_run.py

Index: scripts/slave/annotated_run.py
diff --git a/scripts/slave/annotated_run.py b/scripts/slave/annotated_run.py
index 136e84bde1fd9c6e37f5af71d4a00c1f94b58d0c..ed5b66e313913142df7821b852b1f4940b33df9d 100755
--- a/scripts/slave/annotated_run.py
+++ b/scripts/slave/annotated_run.py
@@ -3,6 +3,7 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import json
 import optparse
 import os
 import subprocess
@@ -23,33 +24,41 @@ from recipe_engine import main as recipe_main
 def get_recipe_properties(factory_properties, build_properties):
   """Constructs the recipe's properties from buildbot's properties.
 
-  This merges factory_properties and build_properties.  Furthermore, it
-  tries to reconstruct the 'recipe' property from builders.pyl if it isn't
-  already there, and in that case merges in properties form builders.pyl.
+  This retrieves the current factory properties from the master_config
+  in the slave's checkout (the factory properties handed to us from the
+  master might be out of date), and merges in the build properties.
+
+  Using the values from the checkout allows us to do things like change
+  the recipe and other factory properties for a builder without needing
+  a master restart.
   """
-  properties = factory_properties.copy()
+  mastername = factory_properties['mastername']
+  buildername = factory_properties['buildername']

[Paweł Hajdan Jr., 2015/06/11 08:38:19]

How does this interact with e.g. running a recipe locally with run_recipe.py
with a different mastername and buildername than in buildbot config (or just
without these properties) for testing?

+
+  # Get the recipe and otherfactory properties from the current
+  # checked-out copies of the master.cfg on the slave, rather than taking what
+  # was handed to us from the master. The latter might be out-of-date.
+  script_path = os.path.join(BUILD_ROOT, 'scripts', 'slave',
+                             'dump_factory_properties.py')
+  dump_cmd = [sys.executable,
+              script_path,
+              mastername,
+              buildername]
+  proc = subprocess.Popen(dump_cmd, cwd=BUILD_ROOT, stdout=subprocess.PIPE)
+  out, _ = proc.communicate()
+  output_obj = json.loads(out)
+
+  if output_obj['result']:
+    raise LookupError('Failed to get the current factory properties for '
+                      '%s on %s: %s' % (buildername, mastername,
+                                        output_obj['message']))
+
+  if 'recipe' not in output_obj['factory_properties']:
+    raise LookupError('Cannot find recipe for %s on %s' %
+                      (buildername, mastername))
+
+  properties = output_obj['factory_properties'].copy()
   properties.update(build_properties)
-
-  # Try to reconstruct the recipe from builders.pyl if not given.
-  if 'recipe' not in properties:
-    mastername = properties['mastername']
-    buildername = properties['buildername']
-
-    master_path = chromium_utils.MasterPath(mastername)
-    builders_file = os.path.join(master_path, 'builders.pyl')
-    if os.path.isfile(builders_file):
-      builders = chromium_utils.ReadBuildersFile(builders_file)
-      assert buildername in builders['builders'], (
-        'buildername %s is not listed in %s' % (buildername, builders_file))
-      builder = builders['builders'][buildername]
-
-      # Update properties with builders.pyl data.
-      properties['recipe'] = builder['recipe']
-      properties.update(builder.get('properties', {}))
-    else:
-      raise LookupError('Cannot find recipe for %s on %s' %
-                        (build_properties['buildername'],
-                        build_properties['mastername']))
   return properties