Add backend description to CAS in a ctor of TargetCache

...instead of adding it preliminarily.

4 files changed, 30 insertions, 36 deletions

diff --git a/src/buildtool/main/main.cpp b/src/buildtool/main/main.cpp
index 544027ca..d125041f 100644
--- a/src/buildtool/main/main.cpp
+++ b/src/buildtool/main/main.cpp
@@ -26,7 +26,6 @@
 #include <optional>
 #include <set>
 #include <string>
-#include <tuple>
 #include <utility>
 #include <variant>
 #include <vector>
@@ -248,23 +247,6 @@ void SetupFileChunker() {
     FileChunker::Initialize();
 }
 
-/// \brief Write backend description (which determines the target cache shard)
-/// to CAS.
-void StoreTargetCacheShard(
-    Storage const& storage,
-    RemoteExecutionConfig const& remote_exec_config) noexcept {
-    auto backend_description =
-        BackendDescription::Describe(remote_exec_config.remote_address,
-                                     remote_exec_config.platform_properties,
-                                     remote_exec_config.dispatch);
-    if (not backend_description) {
-        Logger::Log(LogLevel::Error, backend_description.error());
-        std::exit(kExitFailure);
-    }
-    std::ignore =
-        storage.CAS().StoreBlob(backend_description->GetDescription());
-}
-
 #endif  // BOOTSTRAP_BUILD_TOOL
 
 // returns path relative to `root`.
@@ -820,7 +802,6 @@ auto main(int argc, char* argv[]) -> int {
                     return kExitFailure;
                 }
                 auto const storage = Storage::Create(&*storage_config);
-                StoreTargetCacheShard(storage, remote_exec_config);
 
                 // pack the local context instances to be passed as needed
                 LocalContext const local_context{
@@ -886,7 +867,6 @@ auto main(int argc, char* argv[]) -> int {
                     return kExitFailure;
                 }
                 auto const storage = Storage::Create(&*storage_config);
-                StoreTargetCacheShard(storage, *remote_exec_config);
 
                 // pack the local context instances to be passed as needed
                 LocalContext const local_context{
@@ -967,10 +947,6 @@ auto main(int argc, char* argv[]) -> int {
         }
         auto const storage = Storage::Create(&*storage_config);
 
-#ifndef BOOTSTRAP_BUILD_TOOL
-        StoreTargetCacheShard(storage, *remote_exec_config);
-#endif  // BOOTSTRAP_BUILD_TOOL
-
         auto jobs = arguments.build.build_jobs > 0 ? arguments.build.build_jobs
                                                    : arguments.common.jobs;
 
diff --git a/src/buildtool/serve_api/serve_service/target.cpp b/src/buildtool/serve_api/serve_service/target.cpp
index 6b46dbea..1154bc9c 100644
--- a/src/buildtool/serve_api/serve_service/target.cpp
+++ b/src/buildtool/serve_api/serve_service/target.cpp
@@ -213,16 +213,6 @@ auto TargetService::ServeTarget(
         return ::grpc::Status{::grpc::StatusCode::INTERNAL, err};
     }
 
-    // add backend description to CAS
-    auto execution_backend_dgst =
-        local_context_.storage->CAS().StoreBlob(description->GetDescription());
-    if (not execution_backend_dgst) {
-        std::string err{
-            "Failed to store execution backend description in local CAS"};
-        logger_->Emit(LogLevel::Error, err);
-        return ::grpc::Status{::grpc::StatusCode::INTERNAL, err};
-    }
-
     // get a target cache instance with the correct computed shard
     auto const tc =
         local_context_.storage->TargetCache().WithShard(*description);
diff --git a/src/buildtool/storage/target_cache.hpp b/src/buildtool/storage/target_cache.hpp
index d674a9ed..bd9edb9c 100644
--- a/src/buildtool/storage/target_cache.hpp
+++ b/src/buildtool/storage/target_cache.hpp
@@ -30,6 +30,7 @@
 #include "src/buildtool/common/artifact_digest.hpp"
 #include "src/buildtool/file_system/file_storage.hpp"
 #include "src/buildtool/file_system/object_type.hpp"
+#include "src/buildtool/logging/log_level.hpp"
 #include "src/buildtool/logging/logger.hpp"
 #include "src/buildtool/storage/backend_description.hpp"
 #include "src/buildtool/storage/config.hpp"
@@ -149,7 +150,35 @@ class TargetCache {
               root /
               backend_description.HashContent(cas->GetHashFunction()).hash()},
           uplinker_{*uplinker},
-          backend_description_{std::move(backend_description)} {}
+          backend_description_{std::move(backend_description)} {
+        if constexpr (kDoGlobalUplink) {
+            // Write backend description (which determines the target cache
+            // shard) to CAS. It needs to be added for informational purposes
+            // only, so it is not an error if insertion fails or returns an
+            // unexpected result.
+            auto const id = cas_.StoreBlob(
+                backend_description_.GetDescription(), /*is_executable=*/false);
+
+            auto const expected_hash =
+                file_store_.StorageRoot().filename().string();
+            if (not id) {
+                logger_->Emit(LogLevel::Debug,
+                              "TargetCache: Failed to add backend description "
+                              "{} to the storage:\n{}",
+                              expected_hash,
+                              backend_description_.GetDescription());
+            }
+            else if (id->hash() != expected_hash) {
+                logger_->Emit(LogLevel::Debug,
+                              "TargetCache: backend description was added to "
+                              "the storage with an unexpected hash. Expected "
+                              "{}, added with {}. Content:\n{}",
+                              expected_hash,
+                              id->hash(),
+                              backend_description_.GetDescription());
+            }
+        }
+    }
 
     template <bool kIsLocalGeneration = not kDoGlobalUplink>
         requires(kIsLocalGeneration)
diff --git a/src/buildtool/storage/target_cache.tpp b/src/buildtool/storage/target_cache.tpp
index 5a6acb88..973373b3 100644
--- a/src/buildtool/storage/target_cache.tpp
+++ b/src/buildtool/storage/target_cache.tpp
@@ -22,7 +22,6 @@
 
 #include "nlohmann/json.hpp"
 #include "src/buildtool/crypto/hash_function.hpp"
-#include "src/buildtool/logging/log_level.hpp"
 #include "src/buildtool/storage/target_cache.hpp"
 
 template <bool kDoGlobalUplink>