Refactor configuration handling and integrate command-line argument parsing with args.zig

.gitignore

@@ -12,4 +12,4 @@ docgen_tmp/
 
 .idea/
 
-zocket/*.md
+config/*.md

build.zig

@@ -5,6 +5,11 @@ pub fn build(b: *std.Build) void
     const target   = b.standardTargetOptions(.{});
     const optimize = b.standardOptimizeOption(.{});
 
+    const version = getGitVersion(b);
+
+    const options = b.addOptions();
+    options.addOption([]const u8, "version", version);
+
     // deps
 
     const toml_dep = b.dependency("toml", .{
@@ -12,6 +17,11 @@ pub fn build(b: *std.Build) void
         .optimize = optimize,
     });
 
+    const args_dep = b.dependency("args", .{
+        .target   = target,
+        .optimize = optimize,
+    });
+
     //
 
     const mod = b.addModule("zocket", .{
@@ -20,6 +30,7 @@ pub fn build(b: *std.Build) void
     });
 
     mod.addImport("toml", toml_dep.module("toml"));
+    mod.addImport("args", args_dep.module("args"));
 
     const exe = b.addExecutable(.{
         .name        = "zocket",
@@ -33,6 +44,8 @@ pub fn build(b: *std.Build) void
         }),
     });
 
+    exe.root_module.addOptions("build_options", options);
+
     //
 
     b.installArtifact(exe);
@@ -63,3 +76,14 @@ pub fn build(b: *std.Build) void
     test_step.dependOn(&run_mod_tests.step);
     test_step.dependOn(&run_exe_tests.step);
 }
+
+fn getGitVersion(b: *std.Build) []const u8
+{
+    const result = b.runAllowFail(
+        &.{ "git", "describe", "--tags", "--always", "--dirty" },
+        undefined,
+        .inherit,
+    ) catch return "0.0.0-unknown";
+
+    return b.dupe(std.mem.trim(u8, result, " \n\r\t"));
+}

build.zig.zon

@@ -8,6 +8,10 @@
             .url  = "git+https://github.com/sam701/zig-toml?ref=zig-0.16#8685923e32e8b8a795eb2715684236975a70faed",
             .hash = "toml-0.3.0-bV14BRmKAQAWR0FT0KUKFwVJTImaFhWjSe6HfSMtNZOH",
         },
+        .args = .{
+            .url  = "https://github.com/muhammad-fiaz/args.zig/archive/refs/tags/0.0.8.tar.gz",
+            .hash = "args-0.0.8-8hzgbsBECgD3C0uPaFNcK9UFTZ210rWU4XIhopR8snoA",
+        },
     },
     .paths               = .{
         "build.zig",

src/main.zig

@@ -2,6 +2,10 @@ const zocket = @import("zocket");
 
 const std     = @import("std");
 const builtin = @import("builtin");
+const options = @import("build_options");
+
+
+const args = zocket.deps.args;
 
 pub fn main(init: std.process.Init) !void
 {
@@ -12,20 +16,36 @@ pub fn main(init: std.process.Init) !void
         var arena: std.heap.DebugAllocator(.{}) = .init;
         defer _ = arena.deinit();
 
-        try run(io, arena.allocator(), "zocket/config.toml");
+        try run(io, arena.allocator(), "config/config.toml");
     }
     else
     {
         var arena = std.heap.ArenaAllocator.init(std.heap.smp_allocator);
         defer arena.deinit();
-
         const allocator = arena.allocator();
 
         var tmpArena       = std.heap.ArenaAllocator.init(std.heap.smp_allocator);
         const tmpAllocator = tmpArena.allocator();
 
-        const exe  = try std.process.executableDirPathAlloc(io, tmpAllocator);
+        var parser = try args.ArgumentParser.init(tmpAllocator, .{
-        const path = try std.fs.path.join(allocator, &.{ exe, "zocket/config.toml" });
+            .name        = "zocket",
+            .version     = options.version,
+            .description = "A lightweight Zig WebSocket server and mesh routing daemon.",
+        });
+
+        try parser.addOption("path", .{
+            .short = 'p',
+            .help  = "Configuration-File Path (*.toml)",
+        });
+
+        var result = try parser.parseProcess(init);
+
+        const tmpPath = result.getString("path") orelse blk: {
+            const exe = try std.process.executableDirPathAlloc(io, tmpAllocator);
+            break :blk  try std.Io.Dir.path.join(tmpAllocator, &.{ exe, "config/config.toml" });
+        };
+
+        const path = try allocator.dupe(u8, tmpPath);
 
         tmpArena.deinit();
 
@@ -35,7 +55,16 @@ pub fn main(init: std.process.Init) !void
 
 fn run(io: std.Io, allocator: std.mem.Allocator, path: []const u8) !void
 {
-    const parsed = try zocket.config.parse(io, allocator, path);
+    const parsed = zocket.config.parse(io, allocator, path) catch |err|
+    {
+        const msg: []const u8 = switch (err) {
+            error.FileNotFound => "File not found",
+            error.AccessDenied => "Permission denied reading",
+            else               => "Unexpected error opening",
+        };
+        std.log.err("{s}: '{s}' ({any})\n", .{ msg, path, err });
+        std.process.exit(1);
+    };
     defer parsed.deinit();
 
     const configuration = parsed.value;

src/root.zig

@@ -1,4 +1,8 @@
-const std = @import("std");
+pub const deps = struct {
+    pub const args = @import("args");
+};
+
+
 pub const config = @import("config/config.zig");
 
 test {