gracefully exit

simplify code
clean up dead code

src/server/client.zig

@@ -32,17 +32,31 @@ pub fn start(self: *Client, io: std.Io, alloc: std.mem.Allocator, queue: *std.Io
         for (msgs[0..len]) |msg| {
             switch (msg) {
                 .@"+ok" => {
-                    try writeOk(self.to_client);
+                    _ = try self.to_client.write("+OK\r\n");
                 },
                 .pong => {
-                    try writePong(self.to_client);
+                    _ = try self.to_client.write("PONG\r\n");
                 },
                 .info => |info| {
-                    try writeInfo(self.to_client, info);
+                    _ = try self.to_client.write("INFO ");
+                    try std.json.Stringify.value(info, .{}, self.to_client);
+                    _ = try self.to_client.write("\r\n");
                 },
                 .msg => |m| {
                     defer m.deinit(alloc);
-                    try writeMsg(self.to_client, m);
+                    try self.to_client.print(
+                        "MSG {s} {s} {s} {d}\r\n{s}\r\n",
+                        .{
+                            m.subject,
+                            m.sid,
+                            m.reply_to orelse "",
+                            m.payload.len,
+                            m.payload,
+                        },
+                    );
+                },
+                .@"-err" => |s| {
+                    _ = try self.to_client.print("-ERR '{s}'\r\n", .{s});
                 },
                 else => |m| {
                     std.debug.panic("unimplemented write: {any}\n", .{m});
@@ -60,42 +74,7 @@ pub fn send(self: *Client, io: std.Io, msg: Message) !void {
 }
 
 pub fn next(self: *Client, allocator: std.mem.Allocator) !Message {
-    // std.debug.print("in client awaiting next message\n", .{});
-    // errdefer std.debug.print("actually it was canceled\n", .{});
-    // defer std.debug.print("client returning next message!\n", .{});
     return Message.next(allocator, self.from_client);
-    // return self.send_queue.getOne(io);
-}
-
-fn writeOk(out: *std.Io.Writer) !void {
-    _ = try out.write("+OK\r\n");
-}
-
-fn writeErr(out: *std.Io.Writer, msg: []const u8) !void {
-    _ = try out.print("-ERR '{s}'\r\n", .{msg});
-}
-
-fn writePong(out: *std.Io.Writer) !void {
-    _ = try out.write("PONG\r\n");
-}
-
-pub fn writeInfo(out: *std.Io.Writer, info: Message.ServerInfo) !void {
-    _ = try out.write("INFO ");
-    try std.json.Stringify.value(info, .{}, out);
-    _ = try out.write("\r\n");
-}
-
-fn writeMsg(out: *std.Io.Writer, msg: Message.Msg) !void {
-    try out.print(
-        "MSG {s} {s} {s} {d}\r\n{s}\r\n",
-        .{
-            msg.subject,
-            msg.sid,
-            msg.reply_to orelse "",
-            msg.payload.len,
-            msg.payload,
-        },
-    );
 }
 
 test {

src/server/main.zig

@@ -25,25 +25,45 @@ fn handleSigInt(sig: std.os.linux.SIG) callconv(.c) void {
     keep_running.store(false, .monotonic);
 }
 
-pub fn main(gpa: std.mem.Allocator, server_config: ServerInfo) !void {
+pub fn main(alloc: std.mem.Allocator, server_config: ServerInfo) !void {
     // Configure the signal action
-    // const act = std.posix.Sigaction{
-    //     .handler = .{ .handler = handleSigInt },
-    //     .mask = std.posix.sigemptyset(),
-    //     .flags = 0,
-    // };
-
-    // // Register the handler for SIGINT (Ctrl+C)
-    // std.posix.sigaction(std.posix.SIG.INT, &act, null);
-
-    var server: Server = .{
-        .info = server_config,
+    const act = std.posix.Sigaction{
+        .handler = .{ .handler = handleSigInt },
+        .mask = std.posix.sigemptyset(),
+        .flags = 0,
     };
 
-    var threaded: std.Io.Threaded = .init(gpa, .{});
-    defer threaded.deinit();
-    const io = threaded.io();
+    // Register the handler for SIGINT (Ctrl+C)
+    std.posix.sigaction(std.posix.SIG.INT, &act, null);
 
+    {
+        var dba: std.heap.DebugAllocator(.{}) = .init;
+        dba.backing_allocator = alloc;
+        defer _ = dba.deinit();
+        const gpa = if (builtin.mode == .Debug or builtin.mode == .ReleaseSafe) dba.allocator() else alloc;
+
+        var server: Server = .{
+            .info = server_config,
+        };
+
+        var threaded: std.Io.Threaded = .init(gpa, .{});
+        defer threaded.deinit();
+        const io = threaded.io();
+
+        var server_task = try io.concurrent(start, .{ &server, io, gpa });
+        defer server_task.cancel(io) catch {};
+
+        while (keep_running.load(.monotonic)) {
+            try io.sleep(.fromMilliseconds(1), .awake);
+        }
+
+        std.debug.print("\nShutting down...\n", .{});
+        server_task.cancel(io) catch {};
+    }
+    std.debug.print("Goodbye\n", .{});
+}
+
+pub fn start(server: *Server, io: std.Io, gpa: std.mem.Allocator) !void {
     var tcp_server = try std.Io.net.IpAddress.listen(try std.Io.net.IpAddress.parse(
         server.info.host,
         server.info.port,
@@ -52,46 +72,20 @@ pub fn main(gpa: std.mem.Allocator, server_config: ServerInfo) !void {
 
     var id: usize = 0;
     // Run until SIGINT is handled, then exit gracefully
-    while (keep_running.load(.monotonic)) : (id +%= 1) {
+    while (true) : (id +%= 1) {
         std.debug.print("in server loop\n", .{});
         if (server.clients.contains(id)) continue;
         const stream = try tcp_server.accept(io);
         std.debug.print("accepted connection\n", .{});
-        _ = io.concurrent(handleConnection, .{ &server, gpa, io, id, stream }) catch {
+        _ = io.concurrent(handleConnection, .{ server, gpa, io, id, stream }) catch {
             std.debug.print("could not start concurrent handler for {d}\n", .{id});
             stream.close(io);
         };
     }
-
-    std.debug.print("Exiting gracefully\n", .{});
-}
-
-fn processMsgs(server: *Server, io: std.Io, alloc: std.mem.Allocator) void {
-    while (true) {
-        const msg = server.msg_queue.getOne(io) catch break;
-        defer msg.deinit(alloc);
-
-        for (server.subscriptions.items) |subscription| {
-            if (subjectMatches(subscription.subject, msg.subject)) {
-                const client = server.clients.get(subscription.client_id) orelse {
-                    std.debug.print("trying to publish to a client that no longer exists: {d}", .{subscription.client_id});
-                    continue;
-                };
-                client.send(io, .{ .msg = .{
-                    .subject = msg.subject,
-                    .sid = subscription.sid,
-                    .reply_to = msg.reply_to,
-                    .payload = msg.payload,
-                } }) catch continue;
-            }
-        }
-    }
 }
 
 fn addClient(server: *Server, allocator: std.mem.Allocator, id: usize, client: *Client) !void {
-    // server.clients.lockPointers();
     try server.clients.put(allocator, id, client);
-    // server.clients.unlockPointers();
 }
 
 fn removeClient(server: *Server, io: std.Io, allocator: std.mem.Allocator, id: usize) void {
@@ -185,13 +179,6 @@ fn handleConnection(
     }
 }
 
-// // Result is owned by the caller
-// fn subscribers(server: *Server, gpa: std.mem.Allocator, subject: []const u8) []ClientState {
-//     var acc: std.ArrayList(ClientState) = .empty;
-
-//     return acc.toOwnedSlice();
-// }
-
 fn subjectMatches(expected: []const u8, actual: []const u8) bool {
     return std.mem.eql(u8, expected, actual);
 }
@@ -200,7 +187,7 @@ fn publishMessage(server: *Server, io: std.Io, alloc: std.mem.Allocator, source_
     errdefer {
         if (source_client.connect) |c| {
             if (c.verbose) {
-                source_client.send(io, .@"-err") catch {};
+                source_client.send(io, .{ .@"-err" = "Slow Consumer" }) catch {};
             }
         }
     }
@@ -259,42 +246,3 @@ pub fn createId() []const u8 {
 pub fn createName() []const u8 {
     return "SERVERNAME";
 }
-
-// TESTING
-
-// fn initTestServer() Server {
-//     return .{
-//         .info = .{
-//             .server_id = "ABCD",
-//             .server_name = "test server",
-//             .version = "0.1.2",
-//             .max_payload = 1234,
-//         },
-//     };
-// }
-
-// fn initTestClient(
-//     io: std.Io,
-//     allocator: std.mem.Allocator,
-//     id: usize,
-//     data_from: []const u8,
-// ) !struct {
-//     Client,
-//     *std.Io.Reader,
-//     *std.Io.Writer,
-// } {
-//     return .init(io, allocator, id, .{}, in, out);
-// }
-
-// test {
-//     const gpa = std.testing.allocator;
-//     const io = std.testing.io;
-
-//     const server = initTestServer();
-//     const client: Client = .init(
-//         io,
-//         gpa,
-//         1,
-//         .{},
-//     );
-// }

src/server/message_parser.zig

@@ -43,7 +43,7 @@ pub const Message = union(MessageType) {
     ping,
     pong,
     @"+ok": void,
-    @"-err": void,
+    @"-err": []const u8,
     pub const ServerInfo = struct {
         /// The unique identifier of the NATS server.
         server_id: []const u8,
@@ -416,34 +416,6 @@ fn readSubject(alloc: std.mem.Allocator, in: *std.Io.Reader) ![]const u8 {
     return subject_list.toOwnedSlice(alloc);
 }
 
-fn parseJsonMessage(T: type, alloc: std.mem.Allocator, in: *std.Io.Reader) !T {
-    var reader: std.json.Reader = .init(alloc, in);
-    return std.json.innerParse(T, alloc, &reader, .{
-        .max_value_len = std.json.default_max_value_len,
-        .allocate = .alloc_always,
-    });
-}
-
-fn parsePub(in: *std.Io.Reader) !Message.Pub {
-    const subject = (try in.takeDelimiter(' ')) orelse return error.EndOfStream;
-    const next = (try in.takeDelimiter('\r')) orelse return error.EndOfStream;
-    var reply_to: ?[]const u8 = null;
-    const bytes = std.fmt.parseUnsigned(usize, next, 10) catch blk: {
-        reply_to = next;
-        break :blk try std.fmt.parseUnsigned(usize, (try in.takeDelimiter(' ')) orelse return error.EndOfStream, 10);
-    };
-
-    in.toss(1); // LF
-    const payload = try in.take(bytes);
-
-    return .{
-        .subject = subject,
-        .reply_to = reply_to,
-        .bytes = bytes,
-        .payload = payload,
-    };
-}
-
 inline fn expectStreamBytes(reader: *std.Io.Reader, expected: []const u8) !void {
     if (!std.mem.eql(u8, try reader.take(expected.len), expected)) {
         @branchHint(.unlikely);
@@ -451,74 +423,39 @@ inline fn expectStreamBytes(reader: *std.Io.Reader, expected: []const u8) !void
     }
 }
 
-// try returning error in debug mode, only null in release?
-// pub fn parseNextMessage(alloc: std.mem.Allocator, in: *std.Io.Reader) ?Message {
-//     const message_type: MessageType = blk: {
-//         var word: ["CONNECT".len]u8 = undefined;
-//         var len: usize = 0;
-//         for (&word, 0..) |*b, i| {
-//             const byte = in.takeByte() catch return null;
-//             if (std.ascii.isUpper(byte)) {
-//                 b.* = byte;
-//                 len = i + 1;
-//             } else break;
-//         }
+test "parsing a stream" {
+    const input = "CONNECT {\"verbose\":false,\"pedantic\":false,\"tls_required\":fa" ++
+        "lse,\"name\":\"NATS CLI Version v0.2.4\",\"lang\":\"go\",\"version\":\"1.43" ++
+        ".0\",\"protocol\":1,\"echo\":true,\"headers\":true,\"no_responders\":true}\r" ++
+        "\nPUB hi 3\r\nfoo\r\n";
+    var reader: std.Io.Reader = .fixed(input);
+    var arena: std.heap.ArenaAllocator = .init(std.testing.allocator);
+    defer arena.deinit();
+    const gpa = arena.allocator();
 
-//         break :blk Message.parse(word[0..len]) orelse return null;
-//     };
+    {
+        const msg: Message = try Message.next(gpa, &reader);
+        const expected: Message = .{ .connect = .{
+            .verbose = false,
+            .pedantic = false,
+            .tls_required = false,
+            .name = "NATS CLI Version v0.2.4",
+            .lang = "go",
+            .version = "1.43.0",
+            .protocol = 1,
+            .echo = true,
+            .headers = true,
+            .no_responders = true,
+        } };
 
-//     // defer in.toss(2); // CRLF
-//     return switch (message_type) {
-//         .connect => blk: {
-//             const value: ?Message = .{ .connect = parseJsonMessage(Message.Connect, alloc, in) catch return null };
-
-//             break :blk value;
-//         },
-//         .@"pub" => .{ .@"pub" = parsePub(in) catch |err| std.debug.panic("{}", .{err}) },
-//         .ping => .ping,
-//         else => null,
-//     };
-// }
-
-// test parseNextMessage {
-//     const input = "CONNECT {\"verbose\":false,\"pedantic\":false,\"tls_required\":false,\"name\":\"NATS CLI Version v0.2.4\",\"lang\":\"go\",\"version\":\"1.43.0\",\"protocol\":1,\"echo\":true,\"headers\":true,\"no_responders\":true}\r\nPUB hi 3\r\nfoo\r\n";
-//     var reader: std.Io.Reader = .fixed(input);
-//     var arena: std.heap.ArenaAllocator = .init(std.testing.allocator);
-//     defer arena.deinit();
-//     const gpa = arena.allocator();
-
-//     {
-//         const msg: Message = try Message.next(gpa, &reader);
-//         const expected: Message = .{ .connect = .{
-//             .connect = .{
-//                 .verbose = false,
-//                 .pedantic = false,
-//                 .tls_required = false,
-//                 .name = try gpa.dupe(u8, "NATS CLI Version v0.2.4"),
-//                 .lang = try gpa.dupe(u8, "go"),
-//                 .version = try gpa.dupe(u8, "1.43.0"),
-//                 .protocol = 1,
-//                 .echo = true,
-//                 .headers = true,
-//                 .no_responders = true,
-//             },
-//             .allocator = arena,
-//         } };
-
-//         try std.testing.expectEqualDeep(expected, msg);
-//     }
-//     {
-//         const msg: Message = try Message.next(gpa, &reader);
-//         const expected: Message = .{ .@"pub" = .{
-//             .subject = "hi",
-//             .payload = "foo",
-//         } };
-//         try std.testing.expectEqualDeep(expected, msg);
-//     }
-// }
-
-// test "MessageType.parse performance" {
-//     // Measure perf for parseMemEql
-//     // Measure perf for parseStaticStringMap
-//     // assert parse = fastest perf
-// }
+        try std.testing.expectEqualDeep(expected, msg);
+    }
+    {
+        const msg: Message = try Message.next(gpa, &reader);
+        const expected: Message = .{ .@"pub" = .{
+            .subject = "hi",
+            .payload = "foo",
+        } };
+        try std.testing.expectEqualDeep(expected, msg);
+    }
+}