Add CIPD pin reporting to swarming.

client/cipd.py

Index: client/cipd.py
diff --git a/client/cipd.py b/client/cipd.py
index 8881ef2ecad75d22fd150ea8733fd230e25d6854..cbee59d1df2db4c6c7f139a401f2501479efe5d6 100644
--- a/client/cipd.py
+++ b/client/cipd.py
@@ -4,11 +4,12 @@
 
 """Fetches CIPD client and installs packages."""
 
-__version__ = '0.2'
+__version__ = '0.3'
 
 import collections
 import contextlib
 import hashlib
+import json
 import logging
 import optparse
 import os
@@ -129,6 +130,10 @@ class CipdClient(object):
       tmp_dir (str): if not None, dir for temp files.
       timeout (int): if not None, timeout in seconds for this function to run.
 
+    Returns:
+      Pinned packages in the form of [(package_name, package_id)], which
+      correspond 1:1 with the input packages argument.
+
     Raises:
       Error if could not install packages or timed out.
     """
@@ -137,6 +142,10 @@ class CipdClient(object):
 
     list_file_handle, list_file_path = tempfile.mkstemp(
         dir=tmp_dir, prefix=u'cipd-ensure-list-', suffix='.txt')
+    json_out_file_handle, json_file_path = tempfile.mkstemp(
+      dir=tmp_dir, prefix=u'cipd-ensure-result-', suffix='.json')
+    os.close(json_out_file_handle)
+
     try:
       try:
         for pkg, version in packages:
@@ -150,6 +159,7 @@ class CipdClient(object):
         '-root', site_root,
         '-list', list_file_path,
         '-verbose',  # this is safe because cipd-ensure does not print a lot
+        '-json-output', json_file_path,
       ]
       if cache_dir:
         cmd += ['-cache-dir', cache_dir]
@@ -180,8 +190,12 @@ class CipdClient(object):
         raise Error(
             'Could not install packages; exit code %d\noutput:%s' % (
             exit_code, '\n'.join(output)))
+      with open(json_file_path) as jfile:
+        result_json = json.load(jfile)
+      return [(x['package'], x['instance_id']) for x in result_json['result']]
     finally:
       fs.remove(list_file_path)
+      fs.remove(json_file_path)
 
 
 def get_platform():
@@ -402,21 +416,26 @@ def get_client(
     yield CipdClient(binary_path)
 
 
-def parse_package_args(packages):
+def parse_package_args(packages, with_index=False):
   """Parses --cipd-package arguments.
 
   Assumes |packages| were validated by validate_cipd_options.
 
   Returns:
-    A map {path: [(package, version)]}.
+    A map {path: [(package, version)]}. If with_index is True, the tuples in the
+    map have a third parameter which is the original command line index of that
+    pin.
   """
   result = collections.defaultdict(list)
-  for pkg in packages:
+  for i, pkg in enumerate(packages):
     path, name, version = pkg.split(':', 2)
     path = path.replace('/', os.path.sep)
     if not name:
       raise Error('Invalid package "%s": package name is not specified' % pkg)
     if not version:
       raise Error('Invalid package "%s": version is not specified' % pkg)
-    result[path].append((name, version))
+    if with_index:
+      result[path].append((name, version, i))
+    else:
+      result[path].append((name, version))
   return result