Merge pull request #24 from defold/issue-22-skip-protocol-by-default

Issue 22: Don't send Sec-WebSocket-Protocol unless specified

README.md

@@ -20,3 +20,29 @@ Set it to:
 * `0` to disable debugging (i.e. no debug output).
 * `1` to display state changes.
 * `2` to display the messages sent and received.
+
+## External resources
+
+To verify that your websocket server works, you can test it with some tools.
+
+* [websocat](https://github.com/vi/websocat)
+
+Or, you can test your server on this web page:
+
+* https://www.websocket.org/echo.html
+
+To monitor all the packets sent to/from the client/server, you can use e.g.
+
+* [Wireshark](https://www.wireshark.org)
+
+For command line debugging, there's
+
+* tcpdump: `sudo tcpdump -X -s0 -ilo0 port 8080 ` (example for local ws:// connection)
+
+* tcpdump: `sudo tcpdump -X -s0 host echo.websocket.org` (Monitors packets to/from echo.websocket.org)
+
+## Credits
+
+This extension makes use of the C library WSlay by @tatsuhiro-t:
+
+* https://github.com/tatsuhiro-t/wslay

docs/index.md

@@ -14,18 +14,16 @@ Here is how you connect to a websocket and listen to events:
 ```lua
 local function websocket_callback(self, conn, data)
     if data.event == websocket.EVENT_DISCONNECTED then
-        print("disconnected " .. conn)
+        log("Disconnected: " .. tostring(conn))
         self.connection = nil
+        update_gui(self)
     elseif data.event == websocket.EVENT_CONNECTED then
-        print("Connected " .. conn)
-        -- self.connection = conn
+        update_gui(self)
+        log("Connected: " .. tostring(conn))
     elseif data.event == websocket.EVENT_ERROR then
-        print("Error:", data.message)
+        log("Error: '" .. data.error .. "'")
     elseif data.event == websocket.EVENT_MESSAGE then
-        print("Receiving: '" .. tostring(data.message) .. "'")
-    end
-    elseif data.event == websocket.EVENT_DISCONNECTED then
-        print("Disconnected: '" .. tostring(data.message) .. "'")
+        log("Receiving: '" .. tostring(data.message) .. "'")
     end
 end
 

websocket/api/api.script_api

@@ -17,6 +17,17 @@
         type: table
         desc: optional parameters as properties. The following parameters can be set
         members:
+          - name: timeout
+            type: number
+            desc: Timeout for the connection sequence (milliseconds). Not used on HTML5. (Default is 3000)
+
+          - name: protocol
+            type: string
+            desc: the protocol to use (e.g. 'chat'). If not set, no `Sec-WebSocket-Protocol` header is sent.
+
+          - name: headers
+            type: string
+            desc: list of http headers. Each pair is separated with "\r\n". Not used on HTML5.
 
       - name: callback
         type: function
@@ -48,11 +59,7 @@
 
           - name: message
             type: string
-            desc: The received data. Only valid if event is `websocket.EVENT_MESSAGE`
-
-          - name: error
-            type: string
-            desc: The error string. Only valid if event is `websocket.EVENT_ERROR`
+            desc: The received data if event is `websocket.EVENT_MESSAGE`. Error message otherwise
 
 
     returns:
@@ -65,21 +72,25 @@
             ```lua
               local function websocket_callback(self, conn, data)
                 if data.event == websocket.EVENT_DISCONNECTED then
-                  print("disconnected " .. conn)
+                  log("Disconnected: " .. tostring(conn))
                   self.connection = nil
+                  update_gui(self)
                 elseif data.event == websocket.EVENT_CONNECTED then
-                  print("Connected " .. conn)
-                  -- self.connection = conn
+                  update_gui(self)
+                  log("Connected: " .. tostring(conn))
                 elseif data.event == websocket.EVENT_ERROR then
-                  print("Error:", data.error)
+                  log("Error: '" .. data.message .. "'")
                 elseif data.event == websocket.EVENT_MESSAGE then
-                  print("Receiving: '" .. tostring(data.message) .. "'")
+                  log("Receiving: '" .. tostring(data.message) .. "'")
                 end
               end
 
               function init(self)
                 self.url = "ws://echo.websocket.org"
-                local params = {}
+                local params = {
+                  timeout = 3000,
+                  headers = "Sec-WebSocket-Protocol: chat\r\nOrigin: mydomain.com\r\n"
+                }
                 self.connection = websocket.connect(self.url, params, websocket_callback)
               end
 
@@ -112,6 +123,17 @@
       - name: message
         type: string
         desc: the message to send
+      - name: options
+        type: table
+        desc: options for this particular message. May be `nil`
+        members:
+        - name: type
+          type: number
+          desc: The data type of the message
+
+             - `websocket.DATA_TYPE_BINARY` (default)
+
+             - `websocket.DATA_TYPE_TEXT`
 
     examples:
       - desc: |-

websocket/src/handshake.cpp

@@ -40,8 +40,12 @@ static Result SendClientHandshakeHeaders(WebsocketConnection* conn)
         dmSnPrintf(port, sizeof(port), ":%d", conn->m_Url.m_Port);
 
     dmSocket::Result sr;
-    WS_SENDALL("GET /");
+    WS_SENDALL("GET ");
+    if (conn->m_Url.m_Path[0] == '\0') {
+        WS_SENDALL("/"); // Default to / for empty path
+    } else {
         WS_SENDALL(conn->m_Url.m_Path);
+    }
     WS_SENDALL(" HTTP/1.1\r\n");
     WS_SENDALL("Host: ");
     WS_SENDALL(conn->m_Url.m_Hostname);
@@ -54,9 +58,23 @@ static Result SendClientHandshakeHeaders(WebsocketConnection* conn)
     WS_SENDALL("\r\n");
     WS_SENDALL("Sec-WebSocket-Version: 13\r\n");
 
-    // Add custom protocols
+    if (conn->m_CustomHeaders)
+    {
+        WS_SENDALL(conn->m_CustomHeaders);
+        // make sure we ended with '\r\n'
+        int len = strlen(conn->m_CustomHeaders);
+        bool ended_with_sentinel = len >= 2 && conn->m_CustomHeaders[len - 2] == '\r' && conn->m_CustomHeaders[len - 1] == '\n';
+        if (!ended_with_sentinel)
+        {
+            WS_SENDALL("\r\n");
+        }
+    }
 
-    // Add custom headers
+    if (conn->m_Protocol) {
+        WS_SENDALL("Sec-WebSocket-Protocol: ");
+        WS_SENDALL(conn->m_Protocol);
+        WS_SENDALL("\r\n");
+    }
 
     WS_SENDALL("\r\n");
 
@@ -101,17 +119,12 @@ Result ReceiveHeaders(WebsocketConnection* conn)
 #else
 Result ReceiveHeaders(WebsocketConnection* conn)
 {
-    dmSocket::Selector selector;
-    dmSocket::SelectorZero(&selector);
-    dmSocket::SelectorSet(&selector, dmSocket::SELECTOR_KIND_READ, conn->m_Socket);
-
-    dmSocket::Result sr = dmSocket::Select(&selector, 200*1000);
-
+    dmSocket::Result sr = WaitForSocket(conn, dmSocket::SELECTOR_KIND_READ, SOCKET_WAIT_TIMEOUT);
     if (dmSocket::RESULT_OK != sr)
     {
         if (dmSocket::RESULT_WOULDBLOCK)
         {
-            dmLogWarning("Waiting for socket to be available for reading");
+            DebugLog(2, "Waiting for socket to be available for reading");
             return RESULT_WOULDBLOCK;
         }
 
@@ -194,9 +207,6 @@ Result VerifyHeaders(WebsocketConnection* conn)
     bool connection = false;
     bool upgrade = false;
     bool valid_key = false;
-    const char* protocol = "";
-
-    // TODO: Perhaps also support the Sec-WebSocket-Protocol
 
     // parse the headers in place
     while (r < endtag)

websocket/src/script_util.cpp

@@ -1,8 +1,8 @@
 #include "script_util.h"
 
-namespace dmWebsocket {
+namespace dmScript {
 
-bool luaL_checkbool(lua_State *L, int numArg)
+bool CheckBool(lua_State *L, int numArg)
 {
     bool b = false;
     if (lua_isboolean(L, numArg))
@@ -16,17 +16,17 @@ bool luaL_checkbool(lua_State *L, int numArg)
     return b;
 }
 
-bool luaL_checkboold(lua_State *L, int numArg, int def)
+bool CheckBoold(lua_State *L, int numArg, int def)
 {
     int type = lua_type(L, numArg);
     if (type != LUA_TNONE && type != LUA_TNIL)
     {
-        return luaL_checkbool(L, numArg);
+        return CheckBool(L, numArg);
     }
     return def;
 }
 
-lua_Number luaL_checknumberd(lua_State *L, int numArg, lua_Number def)
+lua_Number CheckNumberd(lua_State *L, int numArg, lua_Number def)
 {
     int type = lua_type(L, numArg);
     if (type != LUA_TNONE && type != LUA_TNIL)
@@ -36,7 +36,7 @@ lua_Number luaL_checknumberd(lua_State *L, int numArg, lua_Number def)
     return def;
 }
 
-char* luaL_checkstringd(lua_State *L, int numArg, const char* def)
+char* CheckStringd(lua_State *L, int numArg, const char* def)
 {
     int type = lua_type(L, numArg);
     if (type != LUA_TNONE && type != LUA_TNIL)
@@ -46,7 +46,7 @@ char* luaL_checkstringd(lua_State *L, int numArg, const char* def)
     return (char*)def;
 }
 
-lua_Number luaL_checktable_number(lua_State *L, int numArg, const char* field, lua_Number def)
+lua_Number CheckTableNumber(lua_State *L, int numArg, const char* field, lua_Number def)
 {
     lua_Number result = def;
     if(lua_istable(L, numArg))
@@ -61,7 +61,7 @@ lua_Number luaL_checktable_number(lua_State *L, int numArg, const char* field, l
     return result;
 }
 
-char* luaL_checktable_string(lua_State *L, int numArg, const char* field, char* def)
+char* CheckTableString(lua_State *L, int numArg, const char* field, char* def)
 {
     char* result = def;
     if(lua_istable(L, numArg))

websocket/src/script_util.h

@@ -2,11 +2,11 @@
 
 #include <dmsdk/sdk.h>
 
-namespace dmWebsocket {
-    bool        luaL_checkbool(lua_State *L, int numArg);
-    bool        luaL_checkboold(lua_State *L, int numArg, int def);
-    lua_Number  luaL_checknumberd(lua_State *L, int numArg, lua_Number def);
-    char*       luaL_checkstringd(lua_State *L, int numArg, const char* def);
-    lua_Number  luaL_checktable_number(lua_State *L, int numArg, const char* field, lua_Number def);
-    char*       luaL_checktable_string(lua_State *L, int numArg, const char* field, char* def);
+namespace dmScript {
+    bool        CheckBool(lua_State *L, int numArg);
+    bool        CheckBoold(lua_State *L, int numArg, int def);
+    lua_Number  CheckNumberd(lua_State *L, int numArg, lua_Number def);
+    char*       CheckStringd(lua_State *L, int numArg, const char* def);
+    lua_Number  CheckTableNumber(lua_State *L, int numArg, const char* field, lua_Number def);
+    char*       CheckTableString(lua_State *L, int numArg, const char* field, char* def);
 } // namespace

websocket/src/websocket.cpp

@@ -87,23 +87,50 @@ void DebugPrint(int level, const char* msg, const void* _bytes, uint32_t num_byt
     if (level > g_DebugWebSocket)
         return;
 
+    char buffer[1024];
+    char submessage[128];
+    uint32_t sublength = 0;
+
+    uint32_t len = dmSnPrintf(buffer, sizeof(buffer), "%s '", msg);
+
     const uint8_t* bytes = (const uint8_t*)_bytes;
-    printf("%s '", msg);
     for (uint32_t i = 0; i < num_bytes; ++i)
     {
+        if (len + 2 >= sizeof(buffer))
+        {
+            dmLogWarning("%s", buffer);
+            buffer[0] = 0;
+            len = 0;
+        }
+
+        sublength = 0;
+
         int c = bytes[i];
         if (isprint(c))
-            printf("%c", c);
+            sublength = dmSnPrintf(submessage, sizeof(submessage), "%c", c);
         else if (c == '\r')
-            printf("\\r");
+            sublength = dmSnPrintf(submessage, sizeof(submessage), "\\r");
         else if (c == '\n')
-            printf("\\n");
+            sublength = dmSnPrintf(submessage, sizeof(submessage), "\\n");
         else if (c == '\t')
-            printf("\\t");
+            sublength = dmSnPrintf(submessage, sizeof(submessage), "\\t");
         else
-            printf("\\%02x", c);
+            sublength = dmSnPrintf(submessage, sizeof(submessage), "\\%02x", c);
+        dmStrlCat(buffer, submessage, sizeof(buffer));
+        len += sublength;
     }
-    printf("' %u bytes\n", num_bytes);
+
+    if (len + 2 >= sizeof(buffer))
+    {
+        dmLogWarning("%s", buffer);
+        buffer[0] = 0;
+        len = 0;
+    }
+
+    sublength = dmSnPrintf(submessage, sizeof(submessage), "' %u bytes", num_bytes);
+    dmStrlCat(buffer, submessage, sizeof(buffer));
+    len += sublength;
+    dmLogWarning("%s", buffer);
 }
 
 
@@ -151,6 +178,7 @@ static WebsocketConnection* CreateConnection(const char* url)
     conn->m_Buffer = (char*)malloc(conn->m_BufferCapacity);
     conn->m_Buffer[0] = 0;
     conn->m_BufferSize = 0;
+    conn->m_ConnectTimeout = 0;
 
     dmURI::Parts uri;
     dmURI::Parse(url, &conn->m_Url);
@@ -167,6 +195,7 @@ static WebsocketConnection* CreateConnection(const char* url)
     conn->m_SSLSocket = 0;
     conn->m_Status = RESULT_OK;
     conn->m_HasHandshakeData = 0;
+    conn->m_WasConnected = 0;
 
 #if defined(HAVE_WSLAY)
     conn->m_Ctx = 0;
@@ -182,6 +211,9 @@ static void DestroyConnection(WebsocketConnection* conn)
         WSL_Exit(conn->m_Ctx);
 #endif
 
+    free((void*)conn->m_CustomHeaders);
+    free((void*)conn->m_Protocol);
+
     if (conn->m_Callback)
         dmScript::DestroyCallback(conn->m_Callback);
 
@@ -199,6 +231,7 @@ static void DestroyConnection(WebsocketConnection* conn)
 
     free((void*)conn->m_Buffer);
     delete conn;
+    DebugLog(2, "DestroyConnection: %p", conn);
 }
 
 
@@ -237,13 +270,22 @@ static int LuaConnect(lua_State* L)
         return DM_LUA_ERROR("The web socket module isn't initialized");
 
     const char* url = luaL_checkstring(L, 1);
+    lua_Number timeout = dmScript::CheckTableNumber(L, 2, "timeout", 3000);
+    const char* custom_headers = dmScript::CheckTableString(L, 2, "headers", 0);
+    const char* protocol = dmScript::CheckTableString(L, 2, "protocol", 0);
 
-    // long playedTime = luaL_checktable_number(L, 2, "playedTime", -1);
-    // long progressValue = luaL_checktable_number(L, 2, "progressValue", -1);
-    // char *description = luaL_checktable_string(L, 2, "description", NULL);
-    // char *coverImage = luaL_checktable_string(L, 2, "coverImage", NULL);
+    if (custom_headers != 0)
+    {
+        if (strstr(custom_headers, "\r\n\r\n") != 0)
+        {
+            return DM_LUA_ERROR("The header field must not contain double '\\r\\n\\r\\n': '%s'", custom_headers);
+        }
+    }
 
     WebsocketConnection* conn = CreateConnection(url);
+    conn->m_ConnectTimeout = dmTime::GetTime() + timeout * 1000;
+    conn->m_CustomHeaders = custom_headers ? strdup(custom_headers) : 0;
+    conn->m_Protocol = protocol ? strdup(protocol) : 0;
 
     conn->m_Callback = dmScript::CreateCallback(L, 3);
 
@@ -298,7 +340,7 @@ static int LuaSend(lua_State* L)
     const char* string = luaL_checklstring(L, 2, &string_length);
 
 #if defined(HAVE_WSLAY)
-    int write_mode = WSLAY_BINARY_FRAME; // or WSLAY_TEXT_FRAME
+    int write_mode = dmScript::CheckTableNumber(L, 3, "type", WSLAY_BINARY_FRAME);
 
     struct wslay_event_msg msg;
     msg.opcode = write_mode;
@@ -376,6 +418,16 @@ static void LuaInit(lua_State* L)
     SETCONSTANT(EVENT_MESSAGE);
     SETCONSTANT(EVENT_ERROR);
 
+#if defined(HAVE_WSLAY)
+    lua_pushnumber(L, (lua_Number) WSLAY_BINARY_FRAME);
+    lua_setfield(L, -2, "DATA_TYPE_BINARY");
+    lua_pushnumber(L, (lua_Number) WSLAY_TEXT_FRAME);
+    lua_setfield(L, -2, "DATA_TYPE_TEXT");
+#else
+    SETCONSTANT(DATA_TYPE_BINARY);
+    SETCONSTANT(DATA_TYPE_TEXT);
+#endif
+
 #undef SETCONSTANT
 
     lua_pop(L, 1);
@@ -491,6 +543,13 @@ Result PushMessage(WebsocketConnection* conn, MessageType type, int length, cons
     return dmWebsocket::RESULT_OK;
 }
 
+// has the connect procedure taken too long?
+static bool CheckConnectTimeout(WebsocketConnection* conn)
+{
+    uint64_t t = dmTime::GetTime();
+    return t >= conn->m_ConnectTimeout;
+}
+
 static dmExtension::Result OnUpdate(dmExtension::Params* params)
 {
     uint32_t size = g_Websocket.m_Connections.Size();
@@ -507,7 +566,10 @@ static dmExtension::Result OnUpdate(dmExtension::Params* params)
                 conn->m_BufferSize = 0;
             }
 
+            if (conn->m_WasConnected)
+            {
                 HandleCallback(conn, EVENT_DISCONNECTED, 0, conn->m_BufferSize);
+            }
 
             g_Websocket.m_Connections.EraseSwap(i);
             --i;
@@ -572,6 +634,12 @@ static dmExtension::Result OnUpdate(dmExtension::Params* params)
         }
         else if (STATE_HANDSHAKE_READ == conn->m_State)
         {
+            if (CheckConnectTimeout(conn))
+            {
+                CLOSE_CONN("Connect sequence timed out");
+                continue;
+            }
+
             Result result = ReceiveHeaders(conn);
             if (RESULT_WOULDBLOCK == result)
             {
@@ -608,11 +676,18 @@ static dmExtension::Result OnUpdate(dmExtension::Params* params)
 #endif
             dmSocket::SetBlocking(conn->m_Socket, false);
 
+            conn->m_WasConnected = 1;
             SetState(conn, STATE_CONNECTED);
             HandleCallback(conn, EVENT_CONNECTED, 0, 0);
         }
         else if (STATE_HANDSHAKE_WRITE == conn->m_State)
         {
+            if (CheckConnectTimeout(conn))
+            {
+                CLOSE_CONN("Connect sequence timed out");
+                continue;
+            }
+
             Result result = SendClientHandshake(conn);
             if (RESULT_WOULDBLOCK == result)
             {
@@ -628,9 +703,20 @@ static dmExtension::Result OnUpdate(dmExtension::Params* params)
         }
         else if (STATE_CONNECTING == conn->m_State)
         {
+            if (CheckConnectTimeout(conn))
+            {
+                CLOSE_CONN("Connect sequence timed out");
+                continue;
+            }
+
 #if defined(__EMSCRIPTEN__)
             conn->m_SSLSocket = dmSSLSocket::INVALID_SOCKET_HANDLE;
 
+            EM_ASM({
+                // https://emscripten.org/docs/porting/networking.html#emulated-posix-tcp-sockets-over-websockets
+                Module["websocket"]["subprotocol"] = $0 ? UTF8ToString($0) : null;
+            }, conn->m_Protocol);
+
             char uri_buffer[dmURI::MAX_URI_LEN];
             const char* uri;
             if (conn->m_Url.m_Path[0] != '\0') {

websocket/src/websocket.h

@@ -66,6 +66,12 @@ namespace dmWebsocket
         MESSAGE_TYPE_CLOSE  = 1,
     };
 
+    enum DataType
+    {
+        DATA_TYPE_BINARY = 0,
+        DATA_TYPE_TEXT   = 1,
+    };
+
     struct Message
     {
         uint32_t m_Length:30;
@@ -83,7 +89,10 @@ namespace dmWebsocket
         dmSocket::Socket                m_Socket;
         dmSSLSocket::Socket             m_SSLSocket;
         dmArray<Message>                m_Messages; // lengths of the messages in the data buffer
+        uint64_t                        m_ConnectTimeout;
         uint8_t                         m_Key[16];
+        const char*                     m_Protocol;
+        const char*                     m_CustomHeaders;
         State                           m_State;
         char*                           m_Buffer;
         int                             m_BufferSize;
@@ -91,6 +100,7 @@ namespace dmWebsocket
         Result                          m_Status;
         uint8_t                         m_SSL:1;
         uint8_t                         m_HasHandshakeData:1;
+        uint8_t                         m_WasConnected:1;
         uint8_t                         :6;
     };