1 files changed, 82 insertions, 0 deletions
diff --git a/src/buildtool/execution_api/local/local_ac.hpp b/src/buildtool/execution_api/local/local_ac.hpp
new file mode 100644
index 00000000..f319940a
--- /dev/null
+++ b/src/buildtool/execution_api/local/local_ac.hpp
@@ -0,0 +1,82 @@
+#ifndef INCLUDED_SRC_BUILDTOOL_EXECUTION_API_LOCAL_LOCAL_AC_HPP
+#define INCLUDED_SRC_BUILDTOOL_EXECUTION_API_LOCAL_LOCAL_AC_HPP
+
+#include "gsl-lite/gsl-lite.hpp"
+#include "src/buildtool/common/bazel_types.hpp"
+#include "src/buildtool/execution_api/common/execution_common.hpp"
+#include "src/buildtool/execution_api/local/config.hpp"
+#include "src/buildtool/execution_api/local/file_storage.hpp"
+#include "src/buildtool/execution_api/local/local_cas.hpp"
+#include "src/buildtool/file_system/file_system_manager.hpp"
+#include "src/buildtool/logging/logger.hpp"
+
+class LocalAC {
+  public:
+    explicit LocalAC(gsl::not_null<LocalCAS<ObjectType::File>*> cas) noexcept
+        : cas_{std::move(cas)} {};
+
+    LocalAC(gsl::not_null<LocalCAS<ObjectType::File>*> cas,
+            std::filesystem::path cache_root) noexcept
+        : cas_{std::move(cas)}, cache_root_{std::move(cache_root)} {}
+
+    LocalAC(LocalAC const&) = delete;
+    LocalAC(LocalAC&&) = delete;
+    auto operator=(LocalAC const&) -> LocalAC& = delete;
+    auto operator=(LocalAC &&) -> LocalAC& = delete;
+    ~LocalAC() noexcept = default;
+
+    [[nodiscard]] auto StoreResult(
+        bazel_re::Digest const& action_id,
+        bazel_re::ActionResult const& result) const noexcept -> bool {
+        auto bytes = result.SerializeAsString();
+        auto digest = cas_->StoreBlobFromBytes(bytes);
+        return (digest and file_store_.AddFromBytes(
+                               action_id.hash(), digest->SerializeAsString()));
+    }
+
+    [[nodiscard]] auto CachedResult(bazel_re::Digest const& action_id)
+        const noexcept -> std::optional<bazel_re::ActionResult> {
+        auto entry_path = file_store_.GetPath(action_id.hash());
+        bazel_re::Digest digest{};
+        auto const entry =
+            FileSystemManager::ReadFile(entry_path, ObjectType::File);
+        if (not entry.has_value()) {
+            logger_.Emit(LogLevel::Debug,
+                         "Cache miss, entry not found {}",
+                         entry_path.string());
+            return std::nullopt;
+        }
+        if (not digest.ParseFromString(*entry)) {
+            logger_.Emit(LogLevel::Warning,
+                         "Parsing cache entry failed failed for action {}",
+                         action_id.hash());
+            return std::nullopt;
+        }
+        auto src_path = cas_->BlobPath(digest);
+        bazel_re::ActionResult result{};
+        if (src_path) {
+            auto const bytes = FileSystemManager::ReadFile(*src_path);
+            if (bytes.has_value() and result.ParseFromString(*bytes)) {
+                return result;
+            }
+        }
+        logger_.Emit(LogLevel::Warning,
+                     "Parsing action result failed for action {}",
+                     action_id.hash());
+        return std::nullopt;
+    }
+
+  private:
+    // The action cache stores the results of failed actions. For those to be
+    // overwritable by subsequent runs we need to choose the store mode "last
+    // wins" for the underlying file storage.
+    static constexpr auto kStoreMode = StoreMode::LastWins;
+
+    Logger logger_{"LocalAC"};
+    gsl::not_null<LocalCAS<ObjectType::File>*> cas_;
+    std::filesystem::path const cache_root_{
+        LocalExecutionConfig::GetCacheDir()};
+    FileStorage<ObjectType::File, kStoreMode> file_store_{cache_root_ / "ac"};
+};
+
+#endif  // INCLUDED_SRC_BUILDTOOL_EXECUTION_API_LOCAL_LOCAL_AC_HPP