structure cleanup: move remote operations of GitRepo to other_tools...

...in order to not include unwanted dependencies in just proper.
The new class extends the GitRepo class used for just's Git tree
operations and gets used in all of just-mr's async maps.

1 files changed, 105 insertions, 0 deletions

diff --git a/src/other_tools/git_operations/git_repo_remote.hpp b/src/other_tools/git_operations/git_repo_remote.hpp
new file mode 100644
index 00000000..83099994
--- /dev/null
+++ b/src/other_tools/git_operations/git_repo_remote.hpp
@@ -0,0 +1,105 @@
+// 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_OTHER_TOOLS_GIT_OPERATIONS_GIT_REPO_REMOTE_HPP
+#define INCLUDED_SRC_OTHER_TOOLS_GIT_OPERATIONS_GIT_REPO_REMOTE_HPP
+
+#include "src/buildtool/file_system/git_repo.hpp"
+
+/// \brief Extension to a Git repository, allowing remote Git operations.
+class GitRepoRemote : public GitRepo {
+  public:
+    GitRepoRemote() = delete;  // no default ctor
+    ~GitRepoRemote() noexcept = default;
+
+    // allow only move, no copy
+    GitRepoRemote(GitRepoRemote const&) = delete;
+    GitRepoRemote(GitRepoRemote&&) noexcept;
+    auto operator=(GitRepoRemote const&) = delete;
+    auto operator=(GitRepoRemote&& other) noexcept -> GitRepoRemote&;
+
+    /// \brief Factory to wrap existing open CAS in a "fake" repository.
+    [[nodiscard]] static auto Open(GitCASPtr git_cas) noexcept
+        -> std::optional<GitRepoRemote>;
+
+    /// \brief Factory to open existing real repository at given location.
+    [[nodiscard]] static auto Open(
+        std::filesystem::path const& repo_path) noexcept
+        -> std::optional<GitRepoRemote>;
+
+    /// \brief Factory to initialize and open new real repository at location.
+    /// Returns nullopt if repository init fails even after repeated tries.
+    [[nodiscard]] static auto InitAndOpen(
+        std::filesystem::path const& repo_path,
+        bool is_bare) noexcept -> std::optional<GitRepoRemote>;
+
+    /// \brief Retrieve commit hash from remote branch given its name.
+    /// Only possible with real repository and thus non-thread-safe.
+    /// Returns the retrieved commit hash, or nullopt if failure.
+    /// It guarantees the logger is called exactly once with fatal if failure.
+    [[nodiscard]] auto GetCommitFromRemote(
+        std::string const& repo_url,
+        std::string const& branch,
+        anon_logger_ptr const& logger) noexcept -> std::optional<std::string>;
+
+    /// \brief Fetch from given remote. It can either fetch a given named
+    /// branch, or it can fetch with base refspecs.
+    /// Only possible with real repository and thus non-thread-safe.
+    /// Returns a success flag.
+    /// It guarantees the logger is called exactly once with fatal if failure.
+    [[nodiscard]] auto FetchFromRemote(std::string const& repo_url,
+                                       std::optional<std::string> const& branch,
+                                       anon_logger_ptr const& logger) noexcept
+        -> bool;
+
+    /// \brief Get commit from remote via a temporary repository.
+    /// Calling it from a fake repository allows thread-safe use.
+    /// Creates a temporary real repository at the given location and uses it to
+    /// retrieve from the remote the commit of a branch given its name.
+    /// Caller needs to make sure the temporary directory exists and that the
+    /// given path is thread- and process-safe!
+    /// Returns the commit hash, as a string, or nullopt if failure.
+    /// It guarantees the logger is called exactly once with fatal if failure.
+    [[nodiscard]] auto UpdateCommitViaTmpRepo(
+        std::filesystem::path const& tmp_repo_path,
+        std::string const& repo_url,
+        std::string const& branch,
+        anon_logger_ptr const& logger) const noexcept
+        -> std::optional<std::string>;
+
+    /// \brief Fetch from a remote via a temporary repository.
+    /// Calling it from a fake repository allows thread-safe use.
+    /// Creates a temporary real repository at the given location and uses a
+    /// custom backend to redirect the fetched objects into the desired odb.
+    /// Caller needs to make sure the temporary directory exists and that the
+    /// given path is thread- and process-safe!
+    /// Uses either a given branch, or fetches using base refspecs.
+    /// Returns a success flag.
+    /// It guarantees the logger is called exactly once with fatal if failure.
+    [[nodiscard]] auto FetchViaTmpRepo(
+        std::filesystem::path const& tmp_repo_path,
+        std::string const& repo_url,
+        std::optional<std::string> const& branch,
+        anon_logger_ptr const& logger) noexcept -> bool;
+
+  private:
+    /// \brief Open "fake" repository wrapper for existing CAS.
+    explicit GitRepoRemote(GitCASPtr git_cas) noexcept;
+    /// \brief Open real repository at given location.
+    explicit GitRepoRemote(std::filesystem::path const& repo_path) noexcept;
+    /// \brief Construct from inherited class.
+    explicit GitRepoRemote(GitRepo&&) noexcept;
+};
+
+#endif  // INCLUDED_SRC_OTHER_TOOLS_GIT_OPERATIONS_GIT_REPO_REMOTE_HPP