just serve protocol: clean up

Just like the remote-execution protocol has several services (Execution,
ActionCache, ContentAddressableStorage, etc), so will the serve
protocol: the actual target-level caching, as well auxilliary
services, like the service to obtain the tree for a given root. Already
follow that scheme, before the protocol gets part of any release.

Also, move the status enum into the respective answer messages. In this
way, we can have different enums for different requests without causing
conflicts on the named enum constants.

1 files changed, 70 insertions, 0 deletions

diff --git a/src/buildtool/serve_api/serve_service/source_tree.hpp b/src/buildtool/serve_api/serve_service/source_tree.hpp
new file mode 100644
index 00000000..a1599508
--- /dev/null
+++ b/src/buildtool/serve_api/serve_service/source_tree.hpp
@@ -0,0 +1,70 @@
+// Copyright 2023 Huawei Cloud Computing Technology Co., Ltd.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef INCLUDED_SRC_BUILDTOOL_SERVE_API_SERVE_SERVICE_SOURCE_TREE_HPP
+#define INCLUDED_SRC_BUILDTOOL_SERVE_API_SERVE_SERVICE_SOURCE_TREE_HPP
+
+#include <filesystem>
+#include <memory>
+#include <optional>
+#include <string>
+#include <vector>
+
+#include "gsl/gsl"
+#include "justbuild/just_serve/just_serve.grpc.pb.h"
+#include "src/buildtool/execution_api/common/execution_api.hpp"
+#include "src/buildtool/execution_api/remote/config.hpp"
+#include "src/buildtool/logging/logger.hpp"
+
+class SourceTreeService final
+    : public justbuild::just_serve::SourceTree::Service {
+
+  public:
+    // Retrieve the tree of a commit.
+    //
+    // This request interrogates the service whether it knows a given Git
+    // commit. If requested commit is found, it provides the commit's
+    // Git-tree identifier.
+    //
+    // Errors:
+    //
+    // * `NOT_FOUND`: The requested commit could not be found.
+    auto ServeCommitTree(
+        ::grpc::ServerContext* context,
+        const ::justbuild::just_serve::ServeCommitTreeRequest* request,
+        ::justbuild::just_serve::ServeCommitTreeResponse* response)
+        -> ::grpc::Status override;
+
+  private:
+    std::shared_ptr<Logger> logger_{std::make_shared<Logger>("serve-service")};
+
+    // remote execution endpoint
+    gsl::not_null<IExecutionApi::Ptr> const remote_api_{
+        CreateExecutionApi(RemoteExecutionConfig::RemoteAddress())};
+    // local api
+    gsl::not_null<IExecutionApi::Ptr> const local_api_{
+        CreateExecutionApi(std::nullopt)};
+
+    [[nodiscard]] static auto CreateExecutionApi(
+        std::optional<RemoteExecutionConfig::ServerAddress> const& address)
+        -> gsl::not_null<IExecutionApi::Ptr>;
+
+    [[nodiscard]] static auto GetTreeFromCommit(
+        std::filesystem::path const& repo_path,
+        std::string const& commit,
+        std::string const& subdir,
+        std::shared_ptr<Logger> const& logger) -> std::optional<std::string>;
+};
+
+#endif