Merge pull request #1955 from lightpanda-io/advertise_host

Add --advertise_host option to serve command

src/Config.zig

@@ -163,6 +163,20 @@ pub fn cdpTimeout(self: *const Config) usize {
     };
 }
 
+pub fn port(self: *const Config) u16 {
+    return switch (self.mode) {
+        .serve => |opts| opts.port,
+        else => unreachable,
+    };
+}
+
+pub fn advertiseHost(self: *const Config) []const u8 {
+    return switch (self.mode) {
+        .serve => |opts| opts.advertise_host orelse opts.host,
+        else => unreachable,
+    };
+}
+
 pub fn webBotAuth(self: *const Config) ?WebBotAuthConfig {
     return switch (self.mode) {
         inline .serve, .fetch, .mcp => |opts| WebBotAuthConfig{
@@ -199,6 +213,7 @@ pub const Mode = union(RunMode) {
 pub const Serve = struct {
     host: []const u8 = "127.0.0.1",
     port: u16 = 9222,
+    advertise_host: ?[]const u8 = null,
     timeout: u31 = 10,
     cdp_max_connections: u16 = 16,
     cdp_max_pending_connections: u16 = 128,
@@ -416,6 +431,11 @@ pub fn printUsageAndExit(self: *const Config, success: bool) void {
         \\--port          Port of the CDP server
         \\                Defaults to 9222
         \\
+        \\--advertise_host
+        \\                The host to advertise, e.g. in the /json/version response.
+        \\                Useful, for example, when --host is 0.0.0.0.
+        \\                Defaults to --host value
+        \\
         \\--timeout       Inactivity timeout in seconds before disconnecting clients
         \\                Defaults to 10 (seconds). Limited to 604800 (1 week).
         \\
@@ -557,6 +577,15 @@ fn parseServeArgs(
             continue;
         }
 
+        if (std.mem.eql(u8, "--advertise_host", opt)) {
+            const str = args.next() orelse {
+                log.fatal(.app, "missing argument value", .{ .arg = "--advertise_host" });
+                return error.InvalidArgument;
+            };
+            serve.advertise_host = try allocator.dupe(u8, str);
+            continue;
+        }
+
         if (std.mem.eql(u8, "--timeout", opt)) {
             const str = args.next() orelse {
                 log.fatal(.app, "missing argument value", .{ .arg = "--timeout" });

src/Server.zig

@@ -45,7 +45,7 @@ clients_pool: std.heap.MemoryPool(Client),
 
 pub fn init(app: *App, address: net.Address) !*Server {
     const allocator = app.allocator;
-    const json_version_response = try buildJSONVersionResponse(allocator, address);
+    const json_version_response = try buildJSONVersionResponse(app);
     errdefer allocator.free(json_version_response);
 
     const self = try allocator.create(Server);
@@ -484,11 +484,17 @@ pub const Client = struct {
 // --------
 
 fn buildJSONVersionResponse(
-    allocator: Allocator,
+    app: *const App,
-    address: net.Address,
 ) ![]const u8 {
-    const body_format = "{{\"webSocketDebuggerUrl\": \"ws://{f}/\"}}";
+    const port = app.config.port();
-    const body_len = std.fmt.count(body_format, .{address});
+    const host = app.config.advertiseHost();
+    if (std.mem.eql(u8, host, "0.0.0.0")) {
+        log.info(.cdp, "unreachable advertised host", .{
+            .message = "when --host is set to 0.0.0.0 consider setting --advertise_host to a reachable address",
+        });
+    }
+    const body_format = "{{\"webSocketDebuggerUrl\": \"ws://{s}:{d}/\"}}";
+    const body_len = std.fmt.count(body_format, .{ host, port });
 
     // We send a Connection: Close (and actually close the connection)
     // because chromedp (Go driver) sends a request to /json/version and then
@@ -502,23 +508,22 @@ fn buildJSONVersionResponse(
         "Connection: Close\r\n" ++
         "Content-Type: application/json; charset=UTF-8\r\n\r\n" ++
         body_format;
-    return try std.fmt.allocPrint(allocator, response_format, .{ body_len, address });
+    return try std.fmt.allocPrint(app.allocator, response_format, .{ body_len, host, port });
 }
 
 pub const timestamp = @import("datetime.zig").timestamp;
 pub const milliTimestamp = @import("datetime.zig").milliTimestamp;
 
-const testing = std.testing;
+const testing = @import("testing.zig");
 test "server: buildJSONVersionResponse" {
-    const address = try net.Address.parseIp4("127.0.0.1", 9001);
+    const res = try buildJSONVersionResponse(testing.test_app);
-    const res = try buildJSONVersionResponse(testing.allocator, address);
+    defer testing.test_app.allocator.free(res);
-    defer testing.allocator.free(res);
 
-    try testing.expectEqualStrings("HTTP/1.1 200 OK\r\n" ++
+    try testing.expectEqual("HTTP/1.1 200 OK\r\n" ++
         "Content-Length: 48\r\n" ++
         "Connection: Close\r\n" ++
         "Content-Type: application/json; charset=UTF-8\r\n\r\n" ++
-        "{\"webSocketDebuggerUrl\": \"ws://127.0.0.1:9001/\"}", res);
+        "{\"webSocketDebuggerUrl\": \"ws://127.0.0.1:9222/\"}", res);
 }
 
 test "Client: http invalid request" {
@@ -526,7 +531,7 @@ test "Client: http invalid request" {
     defer c.deinit();
 
     const res = try c.httpRequest("GET /over/9000 HTTP/1.1\r\n" ++ "Header: " ++ ("a" ** 4100) ++ "\r\n\r\n");
-    try testing.expectEqualStrings("HTTP/1.1 413 \r\n" ++
+    try testing.expectEqual("HTTP/1.1 413 \r\n" ++
         "Connection: Close\r\n" ++
         "Content-Length: 17\r\n\r\n" ++
         "Request too large", res);
@@ -595,7 +600,7 @@ test "Client: http valid handshake" {
         "Custom:  Header-Value\r\n\r\n";
 
     const res = try c.httpRequest(request);
-    try testing.expectEqualStrings("HTTP/1.1 101 Switching Protocols\r\n" ++
+    try testing.expectEqual("HTTP/1.1 101 Switching Protocols\r\n" ++
         "Upgrade: websocket\r\n" ++
         "Connection: upgrade\r\n" ++
         "Sec-Websocket-Accept: flzHu2DevQ2dSCSVqKSii5e9C2o=\r\n\r\n", res);
@@ -723,7 +728,7 @@ test "server: 404" {
     defer c.deinit();
 
     const res = try c.httpRequest("GET /unknown HTTP/1.1\r\n\r\n");
-    try testing.expectEqualStrings("HTTP/1.1 404 \r\n" ++
+    try testing.expectEqual("HTTP/1.1 404 \r\n" ++
         "Connection: Close\r\n" ++
         "Content-Length: 9\r\n\r\n" ++
         "Not found", res);
@@ -735,7 +740,7 @@ test "server: get /json/version" {
         "Content-Length: 48\r\n" ++
         "Connection: Close\r\n" ++
         "Content-Type: application/json; charset=UTF-8\r\n\r\n" ++
-        "{\"webSocketDebuggerUrl\": \"ws://127.0.0.1:9583/\"}";
+        "{\"webSocketDebuggerUrl\": \"ws://127.0.0.1:9222/\"}";
 
     {
         // twice on the same connection
@@ -743,7 +748,7 @@ test "server: get /json/version" {
         defer c.deinit();
 
         const res1 = try c.httpRequest("GET /json/version HTTP/1.1\r\n\r\n");
-        try testing.expectEqualStrings(expected_response, res1);
+        try testing.expectEqual(expected_response, res1);
     }
 
     {
@@ -752,7 +757,7 @@ test "server: get /json/version" {
         defer c.deinit();
 
         const res1 = try c.httpRequest("GET /json/version HTTP/1.1\r\n\r\n");
-        try testing.expectEqualStrings(expected_response, res1);
+        try testing.expectEqual(expected_response, res1);
     }
 }
 
@@ -770,7 +775,7 @@ fn assertHTTPError(
         .{ expected_status, expected_body.len, expected_body },
     );
 
-    try testing.expectEqualStrings(expected_response, res);
+    try testing.expectEqual(expected_response, res);
 }
 
 fn assertWebSocketError(close_code: u16, input: []const u8) !void {
@@ -914,7 +919,7 @@ const TestClient = struct {
             "Custom:  Header-Value\r\n\r\n";
 
         const res = try self.httpRequest(request);
-        try testing.expectEqualStrings("HTTP/1.1 101 Switching Protocols\r\n" ++
+        try testing.expectEqual("HTTP/1.1 101 Switching Protocols\r\n" ++
             "Upgrade: websocket\r\n" ++
             "Connection: upgrade\r\n" ++
             "Sec-Websocket-Accept: flzHu2DevQ2dSCSVqKSii5e9C2o=\r\n\r\n", res);