just-mr: add option to override the absent pragma

Using absent repositories depends on a just-serve endpoint. As
such, it is not a datum of the project, but one of the available
infrastructure. As the latter can change independently of the
project, it is desriable to have the option to specify those pieces
of information in separate files.

1 files changed, 61 insertions, 6 deletions

diff --git a/src/other_tools/just_mr/setup_utils.cpp b/src/other_tools/just_mr/setup_utils.cpp
index b325a71d..332503ea 100644
--- a/src/other_tools/just_mr/setup_utils.cpp
+++ b/src/other_tools/just_mr/setup_utils.cpp
@@ -148,7 +148,8 @@ void DefaultReachableRepositories(
 }
 
 auto ReadConfiguration(
-    std::optional<std::filesystem::path> const& config_file_opt) noexcept
+    std::optional<std::filesystem::path> const& config_file_opt,
+    std::optional<std::filesystem::path> const& absent_file_opt) noexcept
     -> std::shared_ptr<Configuration> {
     if (not config_file_opt) {
         Logger::Log(LogLevel::Error, "Cannot find repository configuration.");
@@ -156,7 +157,7 @@ auto ReadConfiguration(
     }
     auto const& config_file = *config_file_opt;
 
-    std::shared_ptr<Configuration> config{nullptr};
+    auto config = nlohmann::json::object();
     if (not FileSystemManager::IsFile(config_file)) {
         Logger::Log(LogLevel::Error,
                     "Cannot read config file {}.",
@@ -165,14 +166,13 @@ auto ReadConfiguration(
     }
     try {
         std::ifstream fs(config_file);
-        auto map = Expression::FromJson(nlohmann::json::parse(fs));
-        if (not map->IsMap()) {
+        config = nlohmann::json::parse(fs);
+        if (not config.is_object()) {
             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{}",
@@ -180,7 +180,62 @@ auto ReadConfiguration(
                     e.what());
         std::exit(kExitConfigError);
     }
-    return config;
+
+    if (absent_file_opt) {
+        if (not FileSystemManager::IsFile(*absent_file_opt)) {
+            Logger::Log(LogLevel::Error,
+                        "Not file specifying the absent repositories: {}",
+                        absent_file_opt->string());
+            std::exit(kExitConfigError);
+        }
+        try {
+            std::ifstream fs(*absent_file_opt);
+            auto absent = nlohmann::json::parse(fs);
+            if (not absent.is_array()) {
+                Logger::Log(LogLevel::Error,
+                            "Expected {} to contain a list of repository "
+                            "names, but found {}",
+                            absent_file_opt->string(),
+                            absent.dump());
+                std::exit(kExitConfigError);
+            }
+            std::unordered_set<std::string> absent_set{};
+            for (auto const& repo : absent) {
+                if (not repo.is_string()) {
+                    Logger::Log(LogLevel::Error,
+                                "Repositories names have to be strings, but "
+                                "found entry {} in {}",
+                                repo.dump(),
+                                absent_file_opt->string());
+                    std::exit(kExitConfigError);
+                }
+                absent_set.insert(repo);
+            }
+            auto new_repos = nlohmann::json::object();
+            auto repos = config.value("repositories", nlohmann::json::object());
+            for (auto const& [key, val] : repos.items()) {
+                new_repos[key] = val;
+                auto ws = val.value("repository", nlohmann::json::object());
+                auto pragma = ws.value("pragma", nlohmann::json::object());
+                pragma["absent"] = absent_set.contains(key);
+                ws["pragma"] = pragma;
+                new_repos[key]["repository"] = ws;
+            }
+            config["repositories"] = new_repos;
+        } catch (std::exception const& e) {
+            Logger::Log(LogLevel::Error,
+                        "Parsing absent-repos file {} failed with error:\n{}",
+                        absent_file_opt->string(),
+                        e.what());
+            std::exit(kExitConfigError);
+        }
+    }
+
+    try {
+        return std::make_shared<Configuration>(Expression::FromJson(config));
+    } catch (...) {
+        return nullptr;
+    }
 }
 
 auto SetupRemoteApi(std::optional<std::string> const& remote_exec_addr,