Add Config structure, TOML parser, and tests for zocket configuration

build.zig

@@ -1,156 +1,65 @@
 const std = @import("std");
 
-// Although this function looks imperative, it does not perform the build
+pub fn build(b: *std.Build) void
-// directly and instead it mutates the build graph (`b`) that will be then
+{
-// executed by an external runner. The functions in `std.Build` implement a DSL
-// for defining build steps and express dependencies between them, allowing the
-// build runner to parallelize the build automatically (and the cache system to
-// know when a step doesn't need to be re-run).
-pub fn build(b: *std.Build) void {
-    // Standard target options allow the person running `zig build` to choose
-    // what target to build for. Here we do not override the defaults, which
-    // means any target is allowed, and the default is native. Other options
-    // for restricting supported target set are available.
     const target   = b.standardTargetOptions(.{});
-    // Standard optimization options allow the person running `zig build` to select
-    // between Debug, ReleaseSafe, ReleaseFast, and ReleaseSmall. Here we do not
-    // set a preferred release mode, allowing the user to decide how to optimize.
     const optimize = b.standardOptimizeOption(.{});
-    // It's also possible to define more custom flags to toggle optional features
-    // of this build script using `b.option()`. All defined flags (including
-    // target and optimize options) will be listed when running `zig build --help`
-    // in this directory.
 
-    // This creates a module, which represents a collection of source files alongside
+    // deps
-    // some compilation options, such as optimization mode and linked system libraries.
+
-    // Zig modules are the preferred way of making Zig code available to consumers.
+    const toml_dep = b.dependency("toml", .{
-    // addModule defines a module that we intend to make available for importing
+        .target   = target,
-    // to our consumers. We must give it a name because a Zig package can expose
+        .optimize = optimize,
-    // multiple modules and consumers will need to be able to specify which
+    });
-    // module they want to access.
+
+    //
+
     const mod = b.addModule("zocket", .{
-        // The root source file is the "entry point" of this module. Users of
-        // this module will only be able to access public declarations contained
-        // in this file, which means that if you have declarations that you
-        // intend to expose to consumers that were defined in other files part
-        // of this module, you will have to make sure to re-export them from
-        // the root file.
         .root_source_file = b.path("src/root.zig"),
-        // Later on we'll use this module as the root module of a test executable
-        // which requires us to specify a target.
         .target           = target,
     });
 
-    // Here we define an executable. An executable needs to have a root module
+    mod.addImport("toml", toml_dep.module("toml"));
-    // which needs to expose a `main` function. While we could add a main function
+
-    // to the module defined above, it's sometimes preferable to split business
-    // logic and the CLI into two separate modules.
-    //
-    // If your goal is to create a Zig library for others to use, consider if
-    // it might benefit from also exposing a CLI tool. A parser library for a
-    // data serialization format could also bundle a CLI syntax checker, for example.
-    //
-    // If instead your goal is to create an executable, consider if users might
-    // be interested in also being able to embed the core functionality of your
-    // program in their own executable in order to avoid the overhead involved in
-    // subprocessing your CLI tool.
-    //
-    // If neither case applies to you, feel free to delete the declaration you
-    // don't need and to put everything under a single module.
     const exe = b.addExecutable(.{
         .name        = "zocket",
         .root_module = b.createModule(.{
-            // b.createModule defines a new module just like b.addModule but,
-            // unlike b.addModule, it does not expose the module to consumers of
-            // this package, which is why in this case we don't have to give it a name.
             .root_source_file = b.path("src/main.zig"),
-            // Target and optimization levels must be explicitly wired in when
-            // defining an executable or library (in the root module), and you
-            // can also hardcode a specific target for an executable or library
-            // definition if desireable (e.g. firmware for embedded devices).
             .target           = target,
             .optimize         = optimize,
-            // List of modules available for import in source files part of the
-            // root module.
             .imports          = &.{
-                // Here "zocket" is the name you will use in your source code to
-                // import this module (e.g. `@import("zocket")`). The name is
-                // repeated because you are allowed to rename your imports, which
-                // can be extremely useful in case of collisions (which can happen
-                // importing modules from different packages).
                 .{ .name = "zocket", .module = mod },
             },
         }),
     });
 
-    // This declares intent for the executable to be installed into the
+    //
-    // install prefix when running `zig build` (i.e. when executing the default
+
-    // step). By default the install prefix is `zig-out/` but can be overridden
-    // by passing `--prefix` or `-p`.
     b.installArtifact(exe);
 
-    // This creates a top level step. Top level steps have a name and can be
-    // invoked by name when running `zig build` (e.g. `zig build run`).
-    // This will evaluate the `run` step rather than the default step.
-    // For a top level step to actually do something, it must depend on other
-    // steps (e.g. a Run step, as we will see in a moment).
     const run_step = b.step("run", "Run the app");
-
-    // This creates a RunArtifact step in the build graph. A RunArtifact step
-    // invokes an executable compiled by Zig. Steps will only be executed by the
-    // runner if invoked directly by the user (in the case of top level steps)
-    // or if another step depends on it, so it's up to you to define when and
-    // how this Run step will be executed. In our case we want to run it when
-    // the user runs `zig build run`, so we create a dependency link.
     const run_cmd  = b.addRunArtifact(exe);
-    run_step.dependOn(&run_cmd.step);
 
-    // By making the run step depend on the default step, it will be run from the
+    run_step.dependOn(&run_cmd.step);
-    // installation directory rather than directly from within the cache directory.
     run_cmd.step.dependOn(b.getInstallStep());
 
-    // This allows the user to pass arguments to the application in the build
-    // command itself, like this: `zig build run -- arg1 arg2 etc`
     if (b.args) |args| {
         run_cmd.addArgs(args);
     }
 
-    // Creates an executable that will run `test` blocks from the provided module.
-    // Here `mod` needs to define a target, which is why earlier we made sure to
-    // set the releative field.
     const mod_tests = b.addTest(.{
         .root_module = mod,
     });
 
-    // A run step that will run the test executable.
     const run_mod_tests = b.addRunArtifact(mod_tests);
 
-    // Creates an executable that will run `test` blocks from the executable's
-    // root module. Note that test executables only test one module at a time,
-    // hence why we have to create two separate ones.
     const exe_tests  = b.addTest(.{
         .root_module = exe.root_module,
     });
 
-    // A run step that will run the second test executable.
     const run_exe_tests = b.addRunArtifact(exe_tests);
 
-    // A top level step for running all tests. dependOn can be called multiple
-    // times and since the two run steps do not depend on one another, this will
-    // make the two of them run in parallel.
     const test_step = b.step("test", "Run tests");
     test_step.dependOn(&run_mod_tests.step);
     test_step.dependOn(&run_exe_tests.step);
-
-    // Just like flags, top level steps are also listed in the `--help` menu.
-    //
-    // The Zig build system is entirely implemented in userland, which means
-    // that it cannot hook into private compiler APIs. All compilation work
-    // orchestrated by the build system will result in other Zig compiler
-    // subcommands being invoked with the right flags defined. You can observe
-    // these invocations when one fails (or you pass a flag to increase
-    // verbosity) to validate assumptions and diagnose problems.
-    //
-    // Lastly, the Zig build system is relatively simple and self-contained,
-    // and reading its source code will allow you to master it.
 }

src/config/config.zig

@@ -0,0 +1,30 @@
+const Config = @import("models.zig").Config;
+
+const std  = @import("std");
+const toml = @import("toml");
+
+pub fn parse(io: std.Io, allocator: std.mem.Allocator, path: []const u8) !toml.Parsed(Config)
+{
+    var parser = toml.Parser(Config).init(allocator);
+    defer parser.deinit();
+
+    return parser.parseFile(io,path);
+}
+
+test "parse zocket config"
+{
+    var threaded: std.Io.Threaded = .init(std.testing.allocator, .{});
+    defer threaded.deinit();
+    const io = threaded.io();
+
+    const allocator = std.testing.allocator;
+
+    const parsed = try parse(io, allocator, "zocket/config.toml");
+    defer parsed.deinit();
+
+    const cfg = parsed.value;
+    try std.testing.expectEqualStrings("node-01", cfg.node.id);
+    try std.testing.expect(cfg.listen.client.enabled);
+    try std.testing.expectEqual(@as(usize, 1), cfg.mesh.peers.len);
+    try std.testing.expectEqualStrings("node-02", cfg.mesh.peers[0].id);
+}

src/config/models.zig

@@ -0,0 +1,209 @@
+const std  = @import("std");
+const toml = @import("toml");
+
+//
+
+pub const Config = struct {
+    node:    Node, 
+    log:     Log     = .{},
+    listen:  Listen  = .{},
+    mesh:    Mesh    = .{},
+    metrics: Metrics = .{},
+};
+
+//
+
+/// Per-instance identity. Intentionally has no defaults - id/data_dir/private_key
+/// are meaningless without a concrete deployment behind them.
+pub const Node = struct {
+    id:          []const u8,
+    data_dir:    []const u8,
+    private_key: []const u8, // ed25519; auto-generated on first run if missing
+};
+
+pub const LogLevel = enum {
+    debug,
+    info,
+    warn,
+    @"error",
+};
+
+pub const LogFormat = enum {
+    json,
+    text,
+};
+
+pub const Log = struct {
+    level:  LogLevel   = .info,
+    format: LogFormat  = .json,
+    output: []const u8 = "stdout", // or "/path/to/file.log"
+};
+
+pub const Listen = struct {
+    client: ListenClient = .{},
+    peer:   ListenPeer   = .{},
+};
+
+pub const ListenClient = struct {
+    enabled:        bool          = true,
+    bind:           []const u8    = "0.0.0.0:8080",
+    tls:            ClientTls     = .{},
+    auth:           ClientAuth    = .{},
+    access_control: AccessControl = .{},
+    limits:         ClientLimits  = .{},
+};
+
+pub const ClientTls = struct {
+    enabled: bool       = false,
+    cert:    []const u8 = "/etc/zocket/client.crt",
+    key:     []const u8 = "/etc/zocket/client.key",
+};
+
+pub const ClientAuthMode = enum {
+    none,  // clients self-declare their client_id
+    token, // client_id is derived from the matched identity below
+};
+
+pub const ClientAuth = struct {
+    mode:       ClientAuthMode = .token,
+    identities: []Identity     = &[_]Identity{},
+};
+
+/// A single client credential. No defaults as each identity is a distinct
+/// (id, token) pair that must be explicitly provisioned.
+pub const Identity = struct {
+    id:    []const u8,
+    token: []const u8,
+};
+
+/// Shared by listen.client.access_control and listen.peer.access_control.
+pub const AccessControlMode = enum {
+    allowlist,
+    blocklist,
+    disabled,
+};
+
+pub const AccessControl = struct {
+    mode: AccessControlMode = .allowlist,
+    list: [][]const u8      = &[_][]const u8{}, // IP | CIDR entries
+};
+
+pub const ClientLimits = struct {
+    max_message_bytes:  i64        = 65536,
+    max_frame_bytes:    i64        = 65536,
+    idle_timeout_secs:  i64        = 300,
+    ping_interval_secs: i64        = 30,
+    max_missed_pongs:   i64        = 2,
+    max_connections:    i64        = 256,
+    rate_limit:         RateLimit  = .{},
+};
+
+pub const RateLimit = struct {
+    enabled:          bool = true,
+    messages_per_sec: i64  = 50,
+    burst:            i64  = 100,
+};
+
+pub const ListenPeer = struct {
+    enabled:        bool          = true,
+    bind:           []const u8    = "0.0.0.0:8181",
+    tls:            PeerTls       = .{},
+    auth:           PeerAuth      = .{},
+    access_control: AccessControl = .{},
+    limits:         PeerLimits    = .{},
+};
+
+pub const PeerTls = struct {
+    enabled:             bool       = false,
+    cert:                []const u8 = "/etc/zocket/peer.crt",
+    key:                 []const u8 = "/etc/zocket/peer.key",
+    require_client_cert: bool       = false,
+};
+
+pub const PeerAuthMode = enum {
+    pubkey, // only supported mode: signed-nonce challenge, never a shared secret
+};
+
+pub const PeerAuth = struct {
+    mode: PeerAuthMode = .pubkey,
+};
+
+pub const PeerLimits = struct {
+    max_message_bytes:  i64 = 1048576,
+    idle_timeout_secs:  i64 = 60,
+    ping_interval_secs: i64 = 15,
+};
+
+pub const MeshTopology = enum {
+    full,
+    @"static-partial",
+    disabled,
+};
+
+pub const RoutingMode = enum {
+    gossip,
+    reactive,
+    static,
+};
+
+pub const Mesh = struct {
+    enabled:         bool            = true,
+    topology:        MeshTopology    = .full,
+    routing_mode:    RoutingMode     = .gossip,
+    discoverability: Discoverability = .{},
+    peers:           []MeshPeer      = &[_]MeshPeer{},
+    trust:           Trust           = .{},
+    gossip:          Gossip          = .{},
+    broadcast:       Broadcast       = .{},
+    reactive:        Reactive        = .{},
+};
+
+pub const DiscoverabilityMode = enum {
+    // mesh.peers is the complete, manually-maintained set of instances.
+    static,
+    // mesh.peers is just the initial seed; unknown nodes may connect and
+    // prove possession of a pubkey, then get auto-trusted and gossiped
+    // mesh-wide. listen.peer.access_control is the real gate in this mode.
+    broadcast,
+};
+
+pub const Discoverability = struct {
+    mode: DiscoverabilityMode = .static,
+};
+
+/// A statically-pinned peer. No defaults for id/addr/pubkey as pinning a
+/// peer's identity is the entire point, so these must be explicit.
+pub const MeshPeer = struct {
+    id:             []const u8,
+    addr:           []const u8,
+    pubkey:         []const u8,
+    reconnect:      bool = true,
+    backoff_min_ms: i64  = 500,
+    backoff_max_ms: i64  = 30000,
+};
+
+pub const Trust = struct {
+    gossip_new_peers: bool = true, // propagate newly-enrolled peer identities mesh-wide
+};
+
+pub const Gossip = struct {
+    seen_cache_ttl_secs: i64 = 300,
+    route_ttl_secs:      i64 = 0, // 0 = no expiry, rely on explicit ROUTE_REMOVE
+};
+
+pub const Broadcast = struct {
+    // Peer-only (target = "*"); never exposed to clients on listen.client.
+    enabled: bool = true,
+};
+
+pub const Reactive = struct {
+    // Only used when mesh.routing_mode = .reactive.
+    query_ttl_hops:      i64 = 4,
+    query_timeout_ms:    i64 = 2000,
+    negative_cache_secs: i64 = 30,
+};
+
+pub const Metrics = struct {
+    enabled: bool       = true,
+    bind:    []const u8 = "127.0.0.1:9090", // prometheus format
+};

src/main.zig

@@ -1,8 +1,7 @@
-const std = @import("std");
-const Io = std.Io;
-
 const zocket = @import("zocket");
 
+const std = @import("std");
+
 pub fn main(init: std.process.Init) !void
 {
     _ = init;

src/root.zig

@@ -1 +1,6 @@
 const std = @import("std");
+pub const config = @import("config/config.zig");
+
+test {
+    _ = config;
+}

zocket/config.toml

@@ -80,11 +80,6 @@ mode = "pubkey" # pubkey
 # For a KNOWN node_id, the pubkey must match mesh.peers[].pubkey exactly, or the connection is rejected outright.
 # For a claimed node_id that isn't yet known, see mesh.discoverability = "broadcast" below.
 
-[listen.peer.bootstrap]
-enabled = false # only consulted when mesh.discoverability.mode = "broadcast"
-# a bootstrap token grants ONLY "permission to register one new peer identity" —
-# never permission to act as an already-known peer. keep these short-lived / single-use.
-
 [listen.peer.access_control]
 mode = "allowlist"                  # allowlist | blocklist | disabled
 list = ["10.0.0.0/24", "127.0.0.1"] # IP | CIDR
@@ -128,13 +123,15 @@ enabled = true
 # Broadcasting (target = "*") is peer-only and never exposed to clients on listen.client.
 # Floods across peer links using the same seen_cache dedup as gossip route announcements.
 
-[mesh.reactive] # only used if routing_mode = "reactive"
+# only used if routing_mode = "reactive"
+[mesh.reactive]
 query_ttl_hops      = 4
 query_timeout_ms    = 2000
 negative_cache_secs = 30
 
 # ----
 
-[metrics] # prometheus format
+# prometheus format
+[metrics]
 enabled = true
 bind    = "127.0.0.1:9090"