ops: Allow serving both cdp and bidi on the same port

--protocol can now be specified multiple times. This just makes ops/dev easier
by only requiring 1 instance.

.github/workflows/e2e-test.yml

@@ -116,8 +116,7 @@ jobs:
           echo "value=$args" >> "$GITHUB_OUTPUT"
 
       - run: |
-          ./lightpanda serve --port 9222 --protocol cdp ${{ steps.args.outputs.value }} &
-          ./lightpanda serve --port 9223 --protocol webdriver ${{ steps.args.outputs.value }} &
+          ./lightpanda serve --port 9222 --protocol cdp --protocol webdriver ${{ steps.args.outputs.value }} &
 
       - run: |
           go run runner/main.go

src/Config.zig

@@ -386,7 +386,8 @@ const Commands = cli.Builder(.{
             .{ .name = "host", .type = []const u8, .default = "127.0.0.1" },
             .{ .name = "port", .type = u16, .default = 9222 },
             .{ .name = "advertise_host", .type = ?[]const u8 },
-            .{ .name = "protocol", .type = Protocol, .default = Protocol.cdp },
+            // Repeatable; one server can speak several on the same port.
+            .{ .name = "protocol", .type = Protocol, .multiple = true },
             .{ .name = "cdp_max_connections", .type = u16, .default = 16 },
             .{ .name = "cdp_max_pending_connections", .type = u16, .default = 128 },
             .{ .name = "cdp_max_message_size", .type = u32, .default = 1024 * 1024 },
@@ -827,10 +828,10 @@ pub const Protocol = enum {
     webdriver,
 };
 
-pub fn protocol(self: *const Config) Protocol {
+pub fn protocols(self: *const Config) []const Protocol {
     return switch (self.mode) {
-        .serve => |opts| opts.protocol,
-        .mcp => .cdp,
+        .serve => |opts| if (opts.protocol.items.len == 0) &.{.cdp} else opts.protocol.items,
+        .mcp => &.{.cdp},
         else => unreachable,
     };
 }

src/browser/frame/user_input.zig

@@ -18,7 +18,7 @@
 
 // Synthetic user input driving the DOM: mouse, wheel, keyboard, focus
 // navigation and text insertion. These are mostly fed by CDP's Input domain
-// (src/cdp/domains/input.zig) and by EventManager's default activation
+// (src/server/cdp/domains/input.zig) and by EventManager's default activation
 // behavior. Form submission itself lives on the Frame (it's a navigation
 // concern); the activation paths here call into it.
 

src/browser/tools.zig

@@ -21,7 +21,6 @@ const lp = @import("lightpanda");
 const zenai = @import("zenai");
 
 const NodeRegistry = @import("../NodeRegistry.zig");
-const LimitedWriter = @import("../LimitedWriter.zig");
 
 const DOMNode = @import("webapi/Node.zig");
 const Selector = @import("webapi/selector/Selector.zig");

src/help.zon

@@ -48,6 +48,14 @@
     \\  --port <INT>
     \\          Port of the CDP server.
     \\          Defaults to 9222.
+    \\  --protocol <PROTOCOL>
+    \\          Automation protocol to serve. Can be passed multiple times to
+    \\          serve several on the same port.
+    \\          Defaults to cdp.
+    \\          Allowed values:
+    \\              cdp        Chrome DevTools Protocol (WebSocket on /).
+    \\              webdriver  WebDriver BiDi (WebSocket on /session) plus the
+    \\                         classic WebDriver session endpoints.
     ,
     .fetch =
     \\usage: {0s} fetch <url>... [OPTIONS] [COMMON_OPTIONS]

src/server/Server.zig

@@ -160,6 +160,12 @@ pub fn init(app: *App, address: sys_net.IpAddress) !*Server {
     const bidi_session_url = try std.fmt.allocPrint(allocator, "ws://{s}:{d}/session/", .{ app.config.advertiseHost(), port });
     errdefer allocator.free(bidi_session_url);
 
+    var protocols: Handshake.Protocols = .{};
+    for (app.config.protocols()) |p| switch (p) {
+        .cdp => protocols.cdp = true,
+        .webdriver => protocols.webdriver = true,
+    };
+
     self.* = .{
         .app = app,
         .cdp_pool = .empty,
@@ -170,10 +176,7 @@ pub fn init(app: *App, address: sys_net.IpAddress) !*Server {
         .pollfds = pollfds,
         .wakeup_pipe = pipe,
         .poll_snapshot = poll_snapshot,
-        .protocols = switch (app.config.protocol()) {
-            .cdp => .{ .cdp = true },
-            .webdriver => .{ .webdriver = true },
-        },
+        .protocols = protocols,
     };
     return self;
 }
@@ -1468,7 +1471,7 @@ test "server: classic session bootstrap errors" {
 }
 
 test "server: protocol gate" {
-    // The test server serves both; the CLI only ever enables one.
+    // The test server serves both; --protocol picks which a real server does.
     const protocols = &testing.test_cdp_server.?.protocols;
     defer protocols.* = .{ .cdp = true, .webdriver = true };
 

src/server/bidi/remote_value.zig

@@ -484,12 +484,13 @@ pub const Serializer = struct {
         defer self.unsee();
 
         const next_depth = depth + 1;
-        var names = try object.nameIterator();
-        var list: std.ArrayList(Property) = try .initCapacity(self.arena, names.count);
-        while (try names.next()) |name| {
-            const owned = try self.arena.dupe(u8, name);
-            const value = try object.get(owned);
-            list.appendAssumeCapacity(.{ .name = owned, .value = try self.remote(value, next_depth, false) });
+        var it = try object.iterator();
+        var list: std.ArrayList(Property) = try .initCapacity(self.arena, it.count);
+        while (try it.next()) |entry| {
+            list.appendAssumeCapacity(.{
+                .name = try self.arena.dupe(u8, entry.name),
+                .value = try self.remote(entry.value, next_depth, false),
+            });
         }
         return list.items;
     }