Add CIPD pin reporting to swarming.

appengine/swarming/server/task_request.py

Index: appengine/swarming/server/task_request.py
diff --git a/appengine/swarming/server/task_request.py b/appengine/swarming/server/task_request.py
index e4a8062c94bbba0b4a7ea3af7a3fa85dacc37e3f..8b7a5cc1f1882ae1eda42a2a82671711924e0f85 100644
--- a/appengine/swarming/server/task_request.py
+++ b/appengine/swarming/server/task_request.py
@@ -333,11 +333,40 @@ class CipdInput(ndb.Model):
       package_names.add(p.package_name)
     self.packages.sort(key=lambda p: p.package_name)
 
-  def packages_grouped_by_path(self):
-    """Returns sorted [(path), [package]) list. Used by user_task.html."""
+  def packages_grouped_by_path(self, pins):
+    """Returns sorted [(path, [PinInfo, ...])].
+
+    PinInfo is a namedtuple with two fields 'pkg' and 'pin'. 'pkg' is the
+    CipdPackage that was specified in the task request. 'pin' is the CipdPackage
+    that was resolved by the bot at runtime, and contains a full package name as
+    well as a package instance id.
+
+    If pinning information is unavailable, or if 'pkg' already specifies a full
+    pin, 'pin' is None. If 'version' or 'package_name' are the same between
+    'pkg' and 'pin', then the field in 'pin' is None.
+
+    Args:
+      pins - a list of CipdPackages which represent the pin counterparts of
+        self.packages.
+
+    Used by user_task.html.
+    """
+    assert pins is None or len(pins) == len(self.packages)
+    PinInfo = collections.namedtuple('PinInfo', ['pkg', 'pin'])
+    pinned = pins is not None
+
     packages = collections.defaultdict(list)
-    for p in self.packages:
-      packages[p.path].append(p)
+    for i, pkg in enumerate(self.packages):
+      pin = None
+      if pinned:
+        pin = pins[i]
+        if pkg.package_name == pin.package_name:
+          pin.package_name = None
+        if pkg.version == pin.version:
+          pin.version = None
+        if pin.package_name is None and pin.version is None:
+          pin = None
+      packages[pkg.path].append(PinInfo(pkg, pin))
     for pkgs in packages.itervalues():
       pkgs.sort()
     return sorted(packages.iteritems())