Allow Action router to mutate Actions and implement a remote action router

cmd/bb_scheduler/main.go

@@ -92,7 +92,7 @@ func main() {
 		// Create an action router that is responsible for analyzing
 		// incoming execution requests and determining how they are
 		// scheduled.
-		actionRouter, err := routing.NewActionRouterFromConfiguration(configuration.ActionRouter, contentAddressableStorage, int(configuration.MaximumMessageSizeBytes), previousExecutionStatsStore)
+		actionRouter, err := routing.NewActionRouterFromConfiguration(configuration.ActionRouter, contentAddressableStorage, int(configuration.MaximumMessageSizeBytes), previousExecutionStatsStore, grpcClientFactory, dependenciesGroup)
 		if err != nil {
 			return util.StatusWrap(err, "Failed to create action router")
 		}

internal/mock/BUILD.bazel

@@ -263,6 +263,7 @@ gomock(
     name = "initialsizeclass",
     out = "initialsizeclass.go",
     interfaces = [
+        "Analyzer",
         "Learner",
         "PreviousExecutionStatsHandle",
         "PreviousExecutionStatsStore",
@@ -312,6 +313,16 @@ gomock(
     package = "mock",
 )
 
+gomock(
+    name = "remoteactionrouter",
+    out = "remoteactionrouter.go",
+    interfaces = ["ActionRouterClient"],
+    library = "//pkg/proto/remoteactionrouter",
+    mockgen_model_library = "@org_uber_go_mock//mockgen/model",
+    mockgen_tool = "@org_uber_go_mock//mockgen",
+    package = "mock",
+)
+
 gomock(
     name = "remoteworker",
     out = "remoteworker.go",
@@ -430,6 +441,7 @@ go_library(
         ":initialsizeclass.go",
         ":platform.go",
         ":random.go",
+        ":remoteactionrouter.go",
         ":remoteexecution.go",
         ":remoteworker.go",
         ":routing.go",
@@ -465,11 +477,13 @@ go_library(
         "//pkg/proto/cas",
         "//pkg/proto/completedactionlogger",
         "//pkg/proto/outputpathpersistency",
+        "//pkg/proto/remoteactionrouter",
         "//pkg/proto/remoteworker",
         "//pkg/proto/runner",
         "//pkg/scheduler/initialsizeclass",
         "//pkg/scheduler/invocation",
         "//pkg/scheduler/platform",
+        "//pkg/scheduler/routing",
         "@bazel_remote_apis//build/bazel/remote/execution/v2:remote_execution_go_proto",
         "@com_github_buildbarn_bb_storage//pkg/blobstore",
         "@com_github_buildbarn_bb_storage//pkg/blobstore/buffer",

pkg/proto/configuration/scheduler/BUILD.bazel

@@ -9,6 +9,7 @@ proto_library(
     visibility = ["//visibility:public"],
     deps = [
         "@bazel_remote_apis//build/bazel/remote/execution/v2:remote_execution_proto",
+        "@com_github_buildbarn_bb_storage//pkg/proto/configuration/grpc:grpc_proto",
         "@protobuf//:duration_proto",
         "@protobuf//:empty_proto",
     ],
@@ -19,7 +20,10 @@ go_proto_library(
     importpath = "github.com/buildbarn/bb-remote-execution/pkg/proto/configuration/scheduler",
     proto = ":scheduler_proto",
     visibility = ["//visibility:public"],
-    deps = ["@bazel_remote_apis//build/bazel/remote/execution/v2:remote_execution_go_proto"],
+    deps = [
+        "@bazel_remote_apis//build/bazel/remote/execution/v2:remote_execution_go_proto",
+        "@com_github_buildbarn_bb_storage//pkg/proto/configuration/grpc",
+    ],
 )
 
 go_library(

pkg/proto/configuration/scheduler/scheduler.proto

@@ -3,6 +3,7 @@ syntax = "proto3";
 package buildbarn.configuration.scheduler;
 
 import "build/bazel/remote/execution/v2/remote_execution.proto";
+import "github.com/buildbarn/bb-storage/pkg/proto/configuration/grpc/grpc.proto";
 import "google/protobuf/duration.proto";
 import "google/protobuf/empty.proto";
 
@@ -18,6 +19,10 @@ message ActionRouterConfiguration {
     // Demultiplex incoming requests based on the client-provided REv2
     // instance name prefix and platform properties.
     DemultiplexingActionRouterConfiguration demultiplexing = 2;
+
+    // Delegate action routing to a gRPC service, using the protocol defined
+    // in pkg/protocol/remoteactionrouter/remoteactionrouter.proto.
+    RemoteActionRouterConfiguration remote = 3;
   }
 }
 
@@ -88,6 +93,18 @@ message DemultiplexingActionRouterConfiguration {
   ActionRouterConfiguration default_action_router = 3;
 }
 
+message RemoteActionRouterConfiguration {
+  // gRPC client configuration.
+  buildbarn.configuration.grpc.ClientConfiguration grpc_client = 1;
+
+  // The initial size class analyzer that is used. This is performed
+  // locally after receiving the routing decision from the remote service.
+  //
+  // See SimpleActionRouterConfiguration.initial_size_class_analyzer for
+  // details on how to set this field.
+  InitialSizeClassAnalyzerConfiguration initial_size_class_analyzer = 2;
+}
+
 message PlatformKeyExtractorConfiguration {
   oneof kind {
     // Attempt to extract platform properties from the REv2 Action

pkg/proto/remoteactionrouter/BUILD.bazel

@@ -0,0 +1,33 @@
+load("@rules_go//go:def.bzl", "go_library")
+load("@rules_go//proto:def.bzl", "go_proto_library")
+load("@rules_proto//proto:defs.bzl", "proto_library")
+
+proto_library(
+    name = "remoteactionrouter_proto",
+    srcs = ["remoteactionrouter.proto"],
+    import_prefix = "github.com/buildbarn/bb-remote-execution",
+    visibility = ["//visibility:public"],
+    deps = [
+        "@bazel_remote_apis//build/bazel/remote/execution/v2:remote_execution_proto",
+        "@protobuf//:any_proto",
+    ],
+)
+
+go_proto_library(
+    name = "remoteactionrouter_go_proto",
+    compilers = [
+        "@rules_go//proto:go_proto",
+        "@rules_go//proto:go_grpc_v2",
+    ],
+    importpath = "github.com/buildbarn/bb-remote-execution/pkg/proto/remoteactionrouter",
+    proto = ":remoteactionrouter_proto",
+    visibility = ["//visibility:public"],
+    deps = ["@bazel_remote_apis//build/bazel/remote/execution/v2:remote_execution_go_proto"],
+)
+
+go_library(
+    name = "remoteactionrouter",
+    embed = [":remoteactionrouter_go_proto"],
+    importpath = "github.com/buildbarn/bb-remote-execution/pkg/proto/remoteactionrouter",
+    visibility = ["//visibility:public"],
+)