LogDog: Add prefix registration endpoint.

common/proto/logdog/logpb/butler.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 logpb;
 
 import "log.proto";
 import "google/protobuf/timestamp.proto";
@@ skipping 33 matching lines @@
  * messages together into this protocol buffer. Based on Butler bundling
  * settings, this message can represent anything from a single LogRecord to
  * multiple LogRecords belonging to several different streams.
  *
  * Entries in a Log Bundle are fully self-descriptive: no additional information
  * is needed to fully associate the contained data with its proper place in
  * the source log stream.
  */
 message ButlerLogBundle {
   /*
-   * String describing the source of this LogBundle.
-   * This is an unstructured field, and is not intended to be parsed. An
-   * example would be: "Butler @a33967 (Linux/amd64)".
-   *
-   * This field will be used for debugging and internal accounting.
+   * (DEPRECATED) Stream source information. Now supplied during prefix
+   * registration.
    */
-  string source = 1;
+  string deprecated_source = 1;

[nodir, 2016/05/19 16:43:17]

use reserved

[dnj (Google), 2016/05/19 22:52:05]

I think "deprecated" is better here, since it communicates what the state of the
value is. Reserved suggests something else is saving it for usage.

 
   /* The timestamp when this bundle was generated.
    *
    * This field will be used for debugging and internal accounting.
    */
   google.protobuf.Timestamp timestamp = 2;
 
   /*
    * A bundle Entry describes a set of LogEntry messages originating from the
    * same log stream.
@@ skipping 62 matching lines @@
    * The Collector will check the secret prior to ingesting logs. If the
    * secret doesn't match the value recorded by the Coordinator, the log
    * will be discarded.
    *
    * This ensures that only the Butler instance that generated the log stream
    * can emit log data for that stream. It also ensures that only authenticated
    * users can write to a Prefix.
    */
   bytes secret = 6;
 }