LogDog: Implement RegisterPrefix RPC.

common/proto/logdog/svcconfig/config.proto

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 syntax = "proto3";
 
 package svcconfig;
 
 import "transport.proto";
 import "storage.proto";
@@ skipping 21 matching lines @@
   string project = 1;
 
   // The name of the authentication group for administrators.
   string admin_auth_group = 10;
   // The name of the authentication group for backend services.
   string service_auth_group = 11;
 
   // A list of origin URLs that are allowed to perform CORS RPC calls.
   repeated string rpc_allow_origins = 20;
 
+  // The maximum amount of time after a prefix has been registered when log
+  // streams may also be registered under that prefix.
+  //
+  // After the expiration period has passed, new log stream registration will
+  // fail.
+  //
+  // Project or stream configurations may override this by providing >= 0 values

[nodir, 2016/05/17 02:45:59]

s/stream/prefix/?

[dnj (Google), 2016/05/17 14:44:33]

Done.

+  // for prefix expiration. The smallest configured expiration will be applied.
+  google.protobuf.Duration prefix_expiration = 21;
+
   // The full path of the archival Pub/Sub topic.
   //
   // The Coordinator must have permission to publish to this topic.
   string archive_topic = 30;
 
   // The amount of time after an archive request has been dispatched before it
   // should be executed.
   //
   // Since terminal messages can arrive out of order, the archival request may
   // be kicked off before all of the log stream data has been loaded into
@@ skipping 81 matching lines @@
   //     back.
   //
   // Enabling this option will consume roughly twice the archival space, as each
   // stream's data will be archived once as a series of log entries and once as
   // a binary file.
   //
   // Streams without an explicit binary file extension will default to ".bin" if
   // this is enabled.
   bool always_create_binary = 13;
 }