LogDog: Add signed GS URL fetching.

logdog/api/endpoints/coordinator/logs/v1/logs.proto

 // Copyright 2016 The LUCI Authors. All rights reserved.
 // Use of this source code is governed under the Apache License, Version 2.0
 // that can be found in the LICENSE file.
 
 syntax = "proto3";
 
 package logdog;
 
 import "github.com/luci/luci-go/logdog/api/endpoints/coordinator/logs/v1/state.proto";
 import "github.com/luci/luci-go/logdog/api/logpb/log.proto";
 import "google/protobuf/timestamp.proto";
+import "google/protobuf/duration.proto";
 
 // GetRequest is the request structure for the user Get endpoint.
 //
 // If the requested log stream exists, a valid GetRequest will succeed
 // regardless of whether the requested log range was available.
 //
 // Note that this endpoint may return fewer logs than requested due to either
 // availability or internal constraints.
 message GetRequest {
   // The request project to request.
@@ skipping 35 matching lines @@
   // Index and stop if either the end of stream is encountered or there is a
   // missing stream index. A NonContiguous request will remove the latter
   // condition.
   //
   // For example, say the log stream consists of:
   // [3, 4, 6, 7]
   //
   // A contiguous request with Index 3 will return: [3, 4], stopping because
   // 5 is missing. A non-contiguous request will return [3, 4, 6, 7].
   bool non_contiguous = 7;
+
+  // If supplied and >0, return a signed version of the log stream's RecordIO
+  // entry protobuf URL. If signing URLs is not supported, the signed URL
+  // field in the response will be empty.
+  //
+  // The signed URL will have an expiration that is <= the requested expiration.

[Vadim Sh., 2016/11/30 21:03:52]

you mean >=?

[dnj, 2016/12/01 17:39:30]

I mean <=, as in if you request 24 days and the server caps at 1 day, you'll get
1 day.'

The expiration here is a duration, not a time, so it probably will always be <
in practice b/c of delay.

[Vadim Sh., 2016/12/01 19:32:12]

Oh, I thought it would return an URL that lives at least
"sign_entry_url_lifetime" (and possibly more). 

+  google.protobuf.Duration sign_entry_url_lifetime = 8;
 }
 
 // TailRequest is the request structure for the user Tail endpoint. It returns
 // the last log in a given log stream at the time of the request.
 message TailRequest {
   // The request project to request.
   string project = 1;
   // The path of the log stream to get.
   //
   // This can either be a LogDog stream path or the SHA256 hash of a LogDog
@@ skipping 22 matching lines @@
   // The expanded LogStreamDescriptor protobuf. It is intended for JSON
   // consumption.
   //
   // If the GetRequest's Proto field is false, this will be populated;
   // otherwise, the serialized protobuf will be written to the DescriptorProto
   // field.
   logpb.LogStreamDescriptor desc = 3;
 
   // Log represents the set of retrieved log records.
   repeated logpb.LogEntry logs = 4;
+
+  // Holds information about the log stream's signed entry URL.
+  message SignedEntryUrl {
+    // The signed URL value.
+    string value = 1;
+    // The time when this signed URL will expire.
+    google.protobuf.Timestamp expiration = 2;
+  }
+  // An optional signed log entry RecordIO protobuf URL, if requested via
+  // "sign_entry_url_lifetime".
+  SignedEntryUrl signed_entry_url = 5;
 }
 
 // QueryRequest is the request structure for the user Query endpoint.
 message QueryRequest {
   // Trinary represents a trinary value.
   enum Trinary {
     // Both positive and negative results will be returned.
     BOTH = 0;
     // Only positive results will be returned.
     YES = 1;
@@ skipping 227 matching lines @@
 
   // Tail returns the last log in the log stream at the time of the request.
   rpc Tail(TailRequest) returns (GetResponse);
 
   // Query returns log stream paths that match the requested query.
   rpc Query(QueryRequest) returns (QueryResponse);
 
   // List returns log stream paths rooted under the path hierarchy.
   rpc List(ListRequest) returns (ListResponse);
 }