Track merged nudge sources

sync/protocol/client_debug_info.proto

Index: sync/protocol/client_debug_info.proto
diff --git a/sync/protocol/client_debug_info.proto b/sync/protocol/client_debug_info.proto
index 7e4e1a5f961f1d57b5808f35cecdd2af02f0da6b..ab7de4fa8f8c40ebecd2462167f4037643137fd4 100644
--- a/sync/protocol/client_debug_info.proto
+++ b/sync/protocol/client_debug_info.proto
@@ -13,6 +13,24 @@ package sync_pb;
 
 import "get_updates_caller_info.proto";
 
+// Per-type hint information.
+message TypeHint {
+  // The data type this hint applied to.
+  optional int32 data_type_id = 1;
+
+  // Whether or not a valid hint is provided.
+  optional bool has_valid_hint = 2;
+}
+
+// Information about the source that triggered a sync.
+message SourceInfo {
+  // An enum indicating the reason for the nudge.
+  optional GetUpdatesCallerInfo.GetUpdatesSource source = 1;
+
+  // The per-type hint information associated with the nudge.
+  repeated TypeHint type_hint = 2;
+}
+
 // The additional info here is from the StatusController. They get sent when
 // the event SYNC_CYCLE_COMPLETED  is sent.
 message SyncCycleCompletedEventInfo {
@@ -38,6 +56,12 @@ message SyncCycleCompletedEventInfo {
   optional int32 num_updates_downloaded = 8;
   optional int32 num_reflected_updates_downloaded = 9;
   optional GetUpdatesCallerInfo caller_info = 10;

[Nicolas Zea, 2012/11/30 21:46:37]

out of curiosity, should this field be deprecated now?

[rlarocque, 2012/11/30 21:53:09]

I'll admit it's a bit redundant.  This will tell us what the client actually
sent up in the previously completed sync cycle.  The newly added counters below
will tell us all the sources that were merged together to form the caller_info
that was eventually sent.  

Although it should be possible to derive caller_info from source_info, it's not
trivial.  And I can foresee sawzall queries where we might want one or the
other.  Storing both will make some queries more convenient.

I think we should keep both for now and audit these fields once the scheduler
refactor is complete.

+
+  // A list of all the sources that were merged into this session.
+  //
+  // Some scenarios, notably mode switches and canary jobs, can spuriously add
+  // back-to-back duplicate sources to this list.
+  repeated SourceInfo source_info = 11;
 }
 
 // Datatype specifics statistics gathered at association time.