GitCAS::Open: allow specifying the log-level for failure

This method returns a GitCASPtr allowing the caller to handle
failure gracefully. Therefore, logging should be at most at level
Warning as it is up to the caller to provide the fatal error message.
Moreover, it can be at lower level in cases where failure to open
that git cas is not an unexpected event, e.g., when looking for a
blob in local mirrors first.

3 files changed, 14 insertions, 9 deletions

diff --git a/src/buildtool/file_system/TARGETS b/src/buildtool/file_system/TARGETS
index d327af6e..c8c26458 100644
--- a/src/buildtool/file_system/TARGETS
+++ b/src/buildtool/file_system/TARGETS
@@ -70,12 +70,16 @@
   , "name": ["git_cas"]
   , "hdrs": ["git_cas.hpp"]
   , "srcs": ["git_cas.cpp"]
-  , "deps": ["git_utils", "object_type", ["@", "gsl", "", "gsl"]]
+  , "deps":
+    [ "git_utils"
+    , "object_type"
+    , ["@", "gsl", "", "gsl"]
+    , ["src/buildtool/logging", "log_level"]
+    ]
   , "stage": ["src", "buildtool", "file_system"]
   , "private-deps":
     [ "git_context"
     , ["", "libgit2"]
-    , ["src/buildtool/logging", "log_level"]
     , ["src/buildtool/logging", "logging"]
     , ["src/utils/cpp", "hex_string"]
     , ["src/utils/cpp", "path"]
diff --git a/src/buildtool/file_system/git_cas.cpp b/src/buildtool/file_system/git_cas.cpp
index 7e004934..295b5783 100644
--- a/src/buildtool/file_system/git_cas.cpp
+++ b/src/buildtool/file_system/git_cas.cpp
@@ -18,7 +18,6 @@
 #include <mutex>
 
 #include "src/buildtool/file_system/git_context.hpp"
-#include "src/buildtool/logging/log_level.hpp"
 #include "src/buildtool/logging/logger.hpp"
 #include "src/utils/cpp/hex_string.hpp"
 #include "src/utils/cpp/path.hpp"
@@ -54,8 +53,8 @@ GitCAS::GitCAS() noexcept {
     GitContext::Create();
 }
 
-auto GitCAS::Open(std::filesystem::path const& repo_path) noexcept
-    -> GitCASPtr {
+auto GitCAS::Open(std::filesystem::path const& repo_path,
+                  LogLevel log_failure) noexcept -> GitCASPtr {
 #ifdef BOOTSTRAP_BUILD_TOOL
     return nullptr;
 #else
@@ -70,7 +69,7 @@ auto GitCAS::Open(std::filesystem::path const& repo_path) noexcept
                                 GIT_REPOSITORY_OPEN_NO_SEARCH,
                                 nullptr) != 0 or
         repo_ptr == nullptr) {
-        Logger::Log(LogLevel::Error,
+        Logger::Log(log_failure,
                     "Opening git repository {} failed with:\n{}",
                     repo_path.string(),
                     GitLastError());
@@ -81,7 +80,7 @@ auto GitCAS::Open(std::filesystem::path const& repo_path) noexcept
     git_odb* odb_ptr = nullptr;
     if (git_repository_odb(&odb_ptr, result->repo_.get()) != 0 or
         odb_ptr == nullptr) {
-        Logger::Log(LogLevel::Error,
+        Logger::Log(log_failure,
                     "Obtaining git object database {} failed with:\n{}",
                     repo_path.string(),
                     GitLastError());
@@ -97,7 +96,7 @@ auto GitCAS::Open(std::filesystem::path const& repo_path) noexcept
     try {
         result->git_path_ = std::filesystem::absolute(git_path);
     } catch (std::exception const& e) {
-        Logger::Log(LogLevel::Error,
+        Logger::Log(log_failure,
                     "Failed to obtain absolute path for {}: {}",
                     git_path.string(),
                     e.what());
diff --git a/src/buildtool/file_system/git_cas.hpp b/src/buildtool/file_system/git_cas.hpp
index 0b104f54..f63fd543 100644
--- a/src/buildtool/file_system/git_cas.hpp
+++ b/src/buildtool/file_system/git_cas.hpp
@@ -25,6 +25,7 @@
 #include "gsl/gsl"
 #include "src/buildtool/file_system/git_utils.hpp"
 #include "src/buildtool/file_system/object_type.hpp"
+#include "src/buildtool/logging/log_level.hpp"
 
 class GitCAS;
 using GitCASPtr = std::shared_ptr<GitCAS const>;
@@ -33,7 +34,8 @@ using GitCASPtr = std::shared_ptr<GitCAS const>;
 class GitCAS {
   public:
     [[nodiscard]] static auto Open(
-        std::filesystem::path const& repo_path) noexcept -> GitCASPtr;
+        std::filesystem::path const& repo_path,
+        LogLevel log_failure = LogLevel::Warning) noexcept -> GitCASPtr;
 
     [[nodiscard]] static auto CreateEmpty() noexcept -> GitCASPtr;