Merge pull request #483 from imperialCHEPI/refactor_parsing_args

Refactor code for parsing command-line arguments
imperialCHEPI · Aug 16, 2024 · 0e2229f · 0e2229f
2 parents 297d88b + aa6f0be
commit 0e2229f
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Showing 3 changed files with 56 additions and 69 deletions.
diff --git a/src/HealthGPS.Console/command_options.cpp b/src/HealthGPS.Console/command_options.cpp
@@ -19,75 +19,56 @@ cxxopts::Options create_options() {
     return options;
 }
 
-// NOLINTNEXTLINE(modernize-avoid-c-arrays)
-CommandOptions parse_arguments(cxxopts::Options &options, int &argc, char *argv[]) {
+std::optional<CommandOptions> parse_arguments(cxxopts::Options &options, int argc, char **argv) {
     namespace fs = std::filesystem;
 
     CommandOptions cmd;
-    try {
-        cmd.success = true;
-        cmd.exit_code = EXIT_SUCCESS;
-        cmd.verbose = false;
-        auto result = options.parse(argc, argv);
-        if (result.count("help")) {
-            std::cout << options.help() << '\n';
-            cmd.success = false;
-            return cmd;
-        }
+    auto result = options.parse(argc, argv);
 
-        if (result.count("version")) {
-            fmt::print("Version {}\n\n", PROJECT_VERSION);
-            cmd.success = false;
-            return cmd;
-        }
+    if (result.count("help")) {
+        std::cout << options.help() << '\n';
+        return std::nullopt;
+    }
 
-        cmd.verbose = result["verbose"].as<bool>();
-        if (cmd.verbose) {
-            fmt::print(fg(fmt::color::dark_salmon), "Verbose output enabled\n");
-        }
+    if (result.count("version")) {
+        fmt::print("Version {}\n\n", PROJECT_VERSION);
+        return std::nullopt;
+    }
 
-        if (result.count("file")) {
-            cmd.config_file = result["file"].as<std::string>();
-            if (cmd.config_file.is_relative()) {
-                cmd.config_file = std::filesystem::absolute(cmd.config_file);
-                fmt::print("Configuration file..: {}\n", cmd.config_file.string());
-            }
-        }
+    cmd.verbose = result["verbose"].as<bool>();
+    if (cmd.verbose) {
+        fmt::print(fg(fmt::color::dark_salmon), "Verbose output enabled\n");
+    }
 
-        if (!fs::exists(cmd.config_file)) {
-            fmt::print(fg(fmt::color::red), "\nConfiguration file: {} not found.\n",
-                       cmd.config_file.string());
-            cmd.exit_code = EXIT_FAILURE;
-        }
+    cmd.config_file = result["file"].as<std::string>();
+    if (cmd.config_file.is_relative()) {
+        cmd.config_file = std::filesystem::absolute(cmd.config_file);
+        fmt::print("Configuration file: {}\n", cmd.config_file.string());
+    }
 
-        if (result.count("storage")) {
-            auto source = result["storage"].as<std::string>();
+    if (!fs::exists(cmd.config_file)) {
+        throw std::runtime_error(
+            fmt::format("Configuration file: {} not found.", cmd.config_file.string()));
+    }
 
-            fmt::print(fmt::fg(fmt::color::yellow),
-                       "WARNING: Path to data source specified with command-line argument. "
-                       "This functionality is deprecatated and will be removed in future. You "
-                       "should pass the data source via the config file.\n");
-            fmt::print("Data source: {}\n", source);
+    if (result.count("storage")) {
+        auto source = result["storage"].as<std::string>();
 
-            cmd.data_source = hgps::input::DataSource(std::move(source));
-        }
+        fmt::print(fmt::fg(fmt::color::yellow),
+                   "WARNING: Path to data source specified with command-line argument. "
+                   "This functionality is deprecated and will be removed in future. You "
+                   "should pass the data source via the config file.\n");
+        fmt::print("Data source: {}\n", source);
 
-        if (result.count("jobid")) {
-            cmd.job_id = result["jobid"].as<int>();
-            if (cmd.job_id < 1) {
-                fmt::print(fg(fmt::color::red),
-                           "\nJob identifier value outside range: (0 < x) given: {}.\n",
-                           std::to_string(cmd.job_id));
-                cmd.exit_code = EXIT_FAILURE;
-            }
-        }
+        cmd.data_source = hgps::input::DataSource(std::move(source));
+    }
 
-        cmd.success = cmd.exit_code == EXIT_SUCCESS;
-    } catch (const cxxopts::exceptions::exception &ex) {
-        fmt::print(fg(fmt::color::red), "\nInvalid command line argument: {}.\n", ex.what());
-        fmt::print("\n{}\n", options.help());
-        cmd.success = false;
-        cmd.exit_code = EXIT_FAILURE;
+    if (result.count("jobid")) {
+        cmd.job_id = result["jobid"].as<int>();
+        if (cmd.job_id < 1) {
+            throw std::runtime_error(
+                fmt::format("Job identifier value outside range: (0 < x) given: {}.", cmd.job_id));
+        }
     }
 
     return cmd;

diff --git a/src/HealthGPS.Console/command_options.h b/src/HealthGPS.Console/command_options.h
@@ -14,14 +14,8 @@
 namespace hgps {
 /// @brief Defines the Command Line Interface (CLI) arguments options
 struct CommandOptions {
-    /// @brief Indicates whether the argument parsing succeed
-    bool success{};
-
-    /// @brief The exit code to return, in case of CLI arguments parsing failure
-    int exit_code{};
-
     /// @brief The configuration file argument value
-    std::filesystem::path config_file{};
+    std::filesystem::path config_file;
 
     /// @brief The back-end storage full path or URL argument value
     std::optional<hgps::input::DataSource> data_source;
@@ -41,7 +35,7 @@ cxxopts::Options create_options();
 /// @param options The valid CLI options
 /// @param argc Number of input arguments
 /// @param argv List of input arguments
-/// @return User command-line options
-CommandOptions parse_arguments(cxxopts::Options &options, int &argc, char *argv[]);
+/// @return User command-line options or std::nullopt if program should exit
+std::optional<CommandOptions> parse_arguments(cxxopts::Options &options, int argc, char **argv);
 
 } // namespace hgps
diff --git a/src/HealthGPS.Console/program.cpp b/src/HealthGPS.Console/program.cpp
@@ -81,11 +81,23 @@ int main(int argc, char *argv[]) { // NOLINT(bugprone-exception-escape)
 
     // Print application title and parse command line arguments
     print_app_title();
-    auto cmd_args = parse_arguments(options, argc, argv);
-    if (!cmd_args.success) {
-        return cmd_args.exit_code;
+
+    std::optional<CommandOptions> cmd_args_opt;
+    try {
+        cmd_args_opt = parse_arguments(options, argc, argv);
+
+        // We won't get a config if e.g. the user chooses the --help option
+        if (!cmd_args_opt) {
+            return exit_application(EXIT_SUCCESS);
+        }
+    } catch (const std::exception &ex) {
+        fmt::print(fg(fmt::color::red), "\nInvalid command line argument: {}\n", ex.what());
+        fmt::print("\n{}\n", options.help());
+        return exit_application(EXIT_FAILURE);
     }
 
+    const auto &cmd_args = cmd_args_opt.value();
+
     // Parse inputs configuration file, *.json.
     Configuration config;
     try {