LogDog: Update to archival V2.

common/api/logdog_coordinator/services/v1/tasks.proto

Index: common/api/logdog_coordinator/services/v1/tasks.proto
diff --git a/common/api/logdog_coordinator/services/v1/tasks.proto b/common/api/logdog_coordinator/services/v1/tasks.proto
index d208f61c5ae35038c641011b42e00361d355dc36..d7bfabed651ef166a779069027cf97fed42ec3e1 100644
--- a/common/api/logdog_coordinator/services/v1/tasks.proto
+++ b/common/api/logdog_coordinator/services/v1/tasks.proto
@@ -6,12 +6,19 @@ syntax = "proto3";
 
 package logdog;
 
+import "google/protobuf/duration.proto";
+
 // ArchiveTask is a task queue task description for the archival of a single
 // log stream.
 message ArchiveTask {
   // The path of the log stream to archive.
   string path = 1;
 
-  // If true, require that the log stream be complete.
-  bool complete = 2;
+  // The amount of time after the task was created that log stream completeness
+  // will be used as a success criteria. If the task's age is older than this
+  // value, completeness will not be enforced.
+  //
+  // The task's age can be calculated by subtracting its lease expiration time
+  // (leaseTimestamp) from its enqueued timestamp (enqueueTimestamp).

[Vadim Sh., 2016/04/07 01:21:32]

dunno, I'd just use global timestamp and don't bother trying to calculate it
from other fields

if clocks are desyncronized, a lot of bad stuff happens anyway (e.g. SSL may
stop to work). GCE machines are configured to use Google's NTP server by
default, and will almost certainly by in sync with each other and with GAE
clock.

[dnj, 2016/04/11 17:20:04]

Since we have to load the stream state in the Archivist anyway, I'm replacing
this mechanism with just having the Coordinator supply the age as one of the
results of that RPC.

(But yes generically agree)

+  google.protobuf.Duration complete_period = 2;
 }