just-mr utils: Extract setup-related code into separate library

This better separates the utility methods used in just-mr commands
and avoids any cyclic dependencies that might arise in new utility
methods requiring both existing utilities and the command-line
arguments.

1 files changed, 138 insertions, 0 deletions

diff --git a/src/other_tools/just_mr/setup_utils.cpp b/src/other_tools/just_mr/setup_utils.cpp
new file mode 100644
index 00000000..9aad1894
--- /dev/null
+++ b/src/other_tools/just_mr/setup_utils.cpp
@@ -0,0 +1,138 @@
+// 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.
+
+#include "src/other_tools/just_mr/setup_utils.hpp"
+
+#include <fstream>
+#include <unordered_set>
+
+#include "nlohmann/json.hpp"
+#include "src/buildtool/build_engine/expression/expression.hpp"
+#include "src/buildtool/file_system/file_system_manager.hpp"
+#include "src/buildtool/logging/logger.hpp"
+#include "src/other_tools/just_mr/exit_codes.hpp"
+
+namespace JustMR::Utils {
+
+void ReachableRepositories(
+    ExpressionPtr const& repos,
+    std::string const& main,
+    std::shared_ptr<JustMR::SetupRepos> const& setup_repos) {
+    // use temporary sets to avoid duplicates
+    std::unordered_set<std::string> include_repos_set{};
+    if (repos->IsMap()) {
+        // traversal of bindings
+        std::function<void(std::string const&)> traverse =
+            [&](std::string const& repo_name) {
+                if (not include_repos_set.contains(repo_name)) {
+                    // if not found, add it and repeat for its bindings
+                    include_repos_set.insert(repo_name);
+                    // check bindings
+                    auto repos_repo_name =
+                        repos->Get(repo_name, Expression::none_t{});
+                    if (not repos_repo_name.IsNotNull()) {
+                        return;
+                    }
+                    auto bindings =
+                        repos_repo_name->Get("bindings", Expression::none_t{});
+                    if (bindings.IsNotNull() and bindings->IsMap()) {
+                        for (auto const& bound : bindings->Map().Values()) {
+                            if (bound.IsNotNull() and bound->IsString()) {
+                                traverse(bound->String());
+                            }
+                        }
+                    }
+                }
+            };
+        traverse(main);  // traverse all bindings of main repository
+
+        // Add overlay repositories
+        std::unordered_set<std::string> setup_repos_set{include_repos_set};
+        for (auto const& repo : include_repos_set) {
+            auto repos_repo = repos->Get(repo, Expression::none_t{});
+            if (repos_repo.IsNotNull()) {
+                // copy over any present alternative root dirs
+                for (auto const& layer : kAltDirs) {
+                    auto layer_val =
+                        repos_repo->Get(layer, Expression::none_t{});
+                    if (layer_val.IsNotNull() and layer_val->IsString()) {
+                        auto repo_name = layer_val->String();
+                        setup_repos_set.insert(repo_name);
+                    }
+                }
+            }
+        }
+
+        // copy to vectors
+        setup_repos->to_setup.clear();
+        setup_repos->to_setup.reserve(setup_repos_set.size());
+        std::copy(
+            setup_repos_set.begin(),
+            setup_repos_set.end(),
+            std::inserter(setup_repos->to_setup, setup_repos->to_setup.end()));
+        setup_repos->to_include.clear();
+        setup_repos->to_include.reserve(include_repos_set.size());
+        std::copy(include_repos_set.begin(),
+                  include_repos_set.end(),
+                  std::inserter(setup_repos->to_include,
+                                setup_repos->to_include.end()));
+    }
+}
+
+void DefaultReachableRepositories(
+    ExpressionPtr const& repos,
+    std::shared_ptr<JustMR::SetupRepos> const& setup_repos) {
+    if (repos.IsNotNull() and repos->IsMap()) {
+        setup_repos->to_setup = repos->Map().Keys();
+        setup_repos->to_include = setup_repos->to_setup;
+    }
+}
+
+auto ReadConfiguration(
+    std::optional<std::filesystem::path> const& config_file_opt) noexcept
+    -> std::shared_ptr<Configuration> {
+    if (not config_file_opt) {
+        Logger::Log(LogLevel::Error, "Cannot find repository configuration.");
+        std::exit(kExitConfigError);
+    }
+    auto const& config_file = *config_file_opt;
+
+    std::shared_ptr<Configuration> config{nullptr};
+    if (not FileSystemManager::IsFile(config_file)) {
+        Logger::Log(LogLevel::Error,
+                    "Cannot read config file {}.",
+                    config_file.string());
+        std::exit(kExitConfigError);
+    }
+    try {
+        std::ifstream fs(config_file);
+        auto map = Expression::FromJson(nlohmann::json::parse(fs));
+        if (not map->IsMap()) {
+            Logger::Log(LogLevel::Error,
+                        "Config file {} does not contain a JSON object.",
+                        config_file.string());
+            std::exit(kExitConfigError);
+        }
+        config = std::make_shared<Configuration>(map);
+    } catch (std::exception const& e) {
+        Logger::Log(LogLevel::Error,
+                    "Parsing config file {} failed with error:\n{}",
+                    config_file.string(),
+                    e.what());
+        std::exit(kExitConfigError);
+    }
+    return config;
+}
+
+}  // namespace JustMR::Utils