Separate the debugger-client to support the later usage of other communication protocols (#2764)

JerryScript-DCO-1.0-Signed-off-by: Robert Sipka rsipka.uszeged@partner.samsung.com

jerry-debugger/jerry_client_websocket.py

@@ -0,0 +1,135 @@
+#!/usr/bin/env python
+
+# Copyright JS Foundation and other contributors, http://js.foundation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import struct
+from jerry_client_tcp import Socket
+
+MAX_BUFFER_SIZE = 128
+WEBSOCKET_BINARY_FRAME = 2
+WEBSOCKET_FIN_BIT = 0x80
+
+class WebSocket(object):
+    def __init__(self, address, protocol=Socket()):
+
+        self.data_buffer = b""
+        self.protocol = protocol
+        self.address = address
+
+    def __handshake(self):
+        """ Client Handshake Request. """
+        self.__send_data(b"GET /jerry-debugger HTTP/1.1\r\n" +
+                         b"Upgrade: websocket\r\n" +
+                         b"Connection: Upgrade\r\n" +
+                         b"Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==\r\n\r\n")
+
+        # Expected answer from the handshake.
+        expected = (b"HTTP/1.1 101 Switching Protocols\r\n" +
+                    b"Upgrade: websocket\r\n" +
+                    b"Connection: Upgrade\r\n" +
+                    b"Sec-WebSocket-Accept: s3pPLMBiTxaQ9kYGzzhZRbK+xOo=\r\n\r\n")
+
+        len_expected = len(expected)
+
+        while len(self.data_buffer) < len_expected:
+            self.data_buffer += self.protocol.receive_data()
+
+        if self.data_buffer[0:len_expected] != expected:
+            raise Exception("Unexpected handshake")
+
+        if len(self.data_buffer) > len_expected:
+            self.data_buffer = self.data_buffer[len_expected:]
+        else:
+            self.data_buffer = b""
+
+    def connect(self, config_size):
+        """  WebSockets connection. """
+        self.protocol.connect(self.address)
+        self.data_buffer = b""
+        self.__handshake()
+
+        # It will return with the Network configurations, which has the following struct:
+        # header [2] - opcode[1], size[1]
+        # configuration [config_size]
+        len_expected = config_size + 2
+
+        while len(self.data_buffer) < len_expected:
+            self.data_buffer += self.protocol.receive_data()
+
+        expected = struct.pack("BB",
+                               WEBSOCKET_BINARY_FRAME | WEBSOCKET_FIN_BIT,
+                               config_size)
+
+        if self.data_buffer[0:2] != expected:
+            raise Exception("Unexpected configuration")
+
+        result = self.data_buffer[2:len_expected]
+        self.data_buffer = self.data_buffer[len_expected:]
+
+        return result
+
+    def __send_data(self, data):
+        """ Private function to send data using the given protocol. """
+        size = len(data)
+
+        while size > 0:
+            bytes_send = self.protocol.send_data(data)
+            if bytes_send < size:
+                data = data[bytes_send:]
+            size -= bytes_send
+
+    def send_message(self, byte_order, packed_data):
+        """ Send message. """
+        message = struct.pack(byte_order + "BBI",
+                              WEBSOCKET_BINARY_FRAME | WEBSOCKET_FIN_BIT,
+                              WEBSOCKET_FIN_BIT + struct.unpack(byte_order + "B", packed_data[0])[0],
+                              0) + packed_data[1:]
+
+        self.__send_data(message)
+
+    def close(self):
+        """ Close the WebSockets connection. """
+        self.protocol.close()
+
+    def get_message(self, blocking):
+        """ Receive message. """
+
+        # Connection was closed
+        if self.data_buffer is None:
+            return None
+
+        while True:
+            if len(self.data_buffer) >= 2:
+                if ord(self.data_buffer[0]) != WEBSOCKET_BINARY_FRAME | WEBSOCKET_FIN_BIT:
+                    raise Exception("Unexpected data frame")
+
+                size = ord(self.data_buffer[1])
+                if size == 0 or size >= 126:
+                    raise Exception("Unexpected data frame")
+
+                if len(self.data_buffer) >= size + 2:
+                    result = self.data_buffer[2:size + 2]
+                    self.data_buffer = self.data_buffer[size + 2:]
+                    return result
+
+            if not blocking and not self.protocol.ready():
+                return b''
+
+            data = self.protocol.receive_data(MAX_BUFFER_SIZE)
+
+            if not data:
+                self.data_buffer = None
+                return None
+            self.data_buffer += data