Milo: Grpc endpoint for multiple builds on a builder

milo/api/proto/buildbot.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 milo;
 
 import "google/protobuf/timestamp.proto";
 
 // The buildbot service definition.
 service Buildbot {
   rpc GetCompressedMasterJSON(MasterRequest) returns (CompressedMasterJSON) {}
   rpc GetBuildbotBuildJSON(BuildbotBuildRequest) returns (BuildbotBuildJSON) {}
+  rpc GetBuildbotBuildsJSON(BuildbotBuildsRequest) returns (BuildbotBuildsJSON) {}
 }
 
 // The request containing the name of the master.
 message MasterRequest {
   string name = 1;
 }
 
 // The response message containing master information.
 message CompressedMasterJSON {
   // Whether the master is internal or not.
@@ skipping 11 matching lines @@
   string master = 1;
   string builder = 2;
   int64 build_num = 3;
 }
 
 // The response message for a specific build.
 message BuildbotBuildJSON {
   // Json data of the build.
   bytes data = 1;
 }
+
+// The request for multiple build on a builder.
+message BuildbotBuildsRequest {
+  string master = 1;
+  string builder = 2;
+  // Limit to the number of builds to return (default: 20).
+  int32 limit = 3;
+  // Include ongoing builds (default: false).
+  bool include_current = 4;
+}
+
+// The response message for multiple builds in a builder.
+message BuildbotBuildsJSON {
+  repeated BuildbotBuildJSON builds = 1;
+}