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| 1 | +# Licensed under the Apache License, Version 2.0 (the "License"); you may |
| 2 | +# not use this file except in compliance with the License. You may obtain |
| 3 | +# a copy of the License at |
| 4 | +# |
| 5 | +# http://www.apache.org/licenses/LICENSE-2.0 |
| 6 | +# |
| 7 | +# Unless required by applicable law or agreed to in writing, software |
| 8 | +# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| 9 | +# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| 10 | +# License for the specific language governing permissions and limitations |
| 11 | +# under the License. |
| 12 | + |
| 13 | +from kubernetes.client.rest import ApiException |
| 14 | + |
| 15 | +import select |
| 16 | +import certifi |
| 17 | +import time |
| 18 | +import collections |
| 19 | +from websocket import WebSocket, ABNF, enableTrace |
| 20 | +import six |
| 21 | +import ssl |
| 22 | +from six.moves.urllib.parse import urlencode, quote_plus, urlparse, urlunparse |
| 23 | + |
| 24 | +STDIN_CHANNEL = 0 |
| 25 | +STDOUT_CHANNEL = 1 |
| 26 | +STDERR_CHANNEL = 2 |
| 27 | +ERROR_CHANNEL = 3 |
| 28 | +RESIZE_CHANNEL = 4 |
| 29 | + |
| 30 | + |
| 31 | +class WSClient: |
| 32 | + def __init__(self, configuration, url, headers): |
| 33 | + """A websocket client with support for channels. |
| 34 | +
|
| 35 | + Exec command uses different channels for different streams. for |
| 36 | + example, 0 is stdin, 1 is stdout and 2 is stderr. Some other API calls |
| 37 | + like port forwarding can forward different pods' streams to different |
| 38 | + channels. |
| 39 | + """ |
| 40 | + enableTrace(False) |
| 41 | + header = [] |
| 42 | + self._connected = False |
| 43 | + self._channels = {} |
| 44 | + self._all = "" |
| 45 | + |
| 46 | + # We just need to pass the Authorization, ignore all the other |
| 47 | + # http headers we get from the generated code |
| 48 | + if headers and 'authorization' in headers: |
| 49 | + header.append("authorization: %s" % headers['authorization']) |
| 50 | + |
| 51 | + if configuration.ws_streaming_protocol: |
| 52 | + header.append("Sec-WebSocket-Protocol: %s" % |
| 53 | + configuration.ws_streaming_protocol) |
| 54 | + |
| 55 | + if url.startswith('wss://') and configuration.verify_ssl: |
| 56 | + ssl_opts = { |
| 57 | + 'cert_reqs': ssl.CERT_REQUIRED, |
| 58 | + 'ca_certs': configuration.ssl_ca_cert or certifi.where(), |
| 59 | + } |
| 60 | + if configuration.assert_hostname is not None: |
| 61 | + ssl_opts['check_hostname'] = configuration.assert_hostname |
| 62 | + else: |
| 63 | + ssl_opts = {'cert_reqs': ssl.CERT_NONE} |
| 64 | + |
| 65 | + if configuration.cert_file: |
| 66 | + ssl_opts['certfile'] = configuration.cert_file |
| 67 | + if configuration.key_file: |
| 68 | + ssl_opts['keyfile'] = configuration.key_file |
| 69 | + |
| 70 | + self.sock = WebSocket(sslopt=ssl_opts, skip_utf8_validation=False) |
| 71 | + self.sock.connect(url, header=header) |
| 72 | + self._connected = True |
| 73 | + |
| 74 | + def peek_channel(self, channel, timeout=0): |
| 75 | + """Peek a channel and return part of the input, |
| 76 | + empty string otherwise.""" |
| 77 | + self.update(timeout=timeout) |
| 78 | + if channel in self._channels: |
| 79 | + return self._channels[channel] |
| 80 | + return "" |
| 81 | + |
| 82 | + def read_channel(self, channel, timeout=0): |
| 83 | + """Read data from a channel.""" |
| 84 | + if channel not in self._channels: |
| 85 | + ret = self.peek_channel(channel, timeout) |
| 86 | + else: |
| 87 | + ret = self._channels[channel] |
| 88 | + if channel in self._channels: |
| 89 | + del self._channels[channel] |
| 90 | + return ret |
| 91 | + |
| 92 | + def readline_channel(self, channel, timeout=None): |
| 93 | + """Read a line from a channel.""" |
| 94 | + if timeout is None: |
| 95 | + timeout = float("inf") |
| 96 | + start = time.time() |
| 97 | + while self.is_open() and time.time() - start < timeout: |
| 98 | + if channel in self._channels: |
| 99 | + data = self._channels[channel] |
| 100 | + if "\n" in data: |
| 101 | + index = data.find("\n") |
| 102 | + ret = data[:index] |
| 103 | + data = data[index+1:] |
| 104 | + if data: |
| 105 | + self._channels[channel] = data |
| 106 | + else: |
| 107 | + del self._channels[channel] |
| 108 | + return ret |
| 109 | + self.update(timeout=(timeout - time.time() + start)) |
| 110 | + |
| 111 | + def write_channel(self, channel, data): |
| 112 | + """Write data to a channel.""" |
| 113 | + self.sock.send(chr(channel) + data) |
| 114 | + |
| 115 | + def peek_stdout(self, timeout=0): |
| 116 | + """Same as peek_channel with channel=1.""" |
| 117 | + return self.peek_channel(STDOUT_CHANNEL, timeout=timeout) |
| 118 | + |
| 119 | + def read_stdout(self, timeout=None): |
| 120 | + """Same as read_channel with channel=1.""" |
| 121 | + return self.read_channel(STDOUT_CHANNEL, timeout=timeout) |
| 122 | + |
| 123 | + def readline_stdout(self, timeout=None): |
| 124 | + """Same as readline_channel with channel=1.""" |
| 125 | + return self.readline_channel(STDOUT_CHANNEL, timeout=timeout) |
| 126 | + |
| 127 | + def peek_stderr(self, timeout=0): |
| 128 | + """Same as peek_channel with channel=2.""" |
| 129 | + return self.peek_channel(STDERR_CHANNEL, timeout=timeout) |
| 130 | + |
| 131 | + def read_stderr(self, timeout=None): |
| 132 | + """Same as read_channel with channel=2.""" |
| 133 | + return self.read_channel(STDERR_CHANNEL, timeout=timeout) |
| 134 | + |
| 135 | + def readline_stderr(self, timeout=None): |
| 136 | + """Same as readline_channel with channel=2.""" |
| 137 | + return self.readline_channel(STDERR_CHANNEL, timeout=timeout) |
| 138 | + |
| 139 | + def read_all(self): |
| 140 | + """Return buffered data received on stdout and stderr channels. |
| 141 | + This is useful for non-interactive call where a set of command passed |
| 142 | + to the API call and their result is needed after the call is concluded. |
| 143 | + Should be called after run_forever() or update() |
| 144 | +
|
| 145 | + TODO: Maybe we can process this and return a more meaningful map with |
| 146 | + channels mapped for each input. |
| 147 | + """ |
| 148 | + out = self._all |
| 149 | + self._all = "" |
| 150 | + self._channels = {} |
| 151 | + return out |
| 152 | + |
| 153 | + def is_open(self): |
| 154 | + """True if the connection is still alive.""" |
| 155 | + return self._connected |
| 156 | + |
| 157 | + def write_stdin(self, data): |
| 158 | + """The same as write_channel with channel=0.""" |
| 159 | + self.write_channel(STDIN_CHANNEL, data) |
| 160 | + |
| 161 | + def update(self, timeout=0): |
| 162 | + """Update channel buffers with at most one complete frame of input.""" |
| 163 | + if not self.is_open(): |
| 164 | + return |
| 165 | + if not self.sock.connected: |
| 166 | + self._connected = False |
| 167 | + return |
| 168 | + r, _, _ = select.select( |
| 169 | + (self.sock.sock, ), (), (), timeout) |
| 170 | + if r: |
| 171 | + op_code, frame = self.sock.recv_data_frame(True) |
| 172 | + if op_code == ABNF.OPCODE_CLOSE: |
| 173 | + self._connected = False |
| 174 | + return |
| 175 | + elif op_code == ABNF.OPCODE_BINARY or op_code == ABNF.OPCODE_TEXT: |
| 176 | + data = frame.data |
| 177 | + if six.PY3: |
| 178 | + data = data.decode("utf-8") |
| 179 | + if len(data) > 1: |
| 180 | + channel = ord(data[0]) |
| 181 | + data = data[1:] |
| 182 | + if data: |
| 183 | + if channel in [STDOUT_CHANNEL, STDERR_CHANNEL]: |
| 184 | + # keeping all messages in the order they received for |
| 185 | + # non-blocking call. |
| 186 | + self._all += data |
| 187 | + if channel not in self._channels: |
| 188 | + self._channels[channel] = data |
| 189 | + else: |
| 190 | + self._channels[channel] += data |
| 191 | + |
| 192 | + def run_forever(self, timeout=None): |
| 193 | + """Wait till connection is closed or timeout reached. Buffer any input |
| 194 | + received during this time.""" |
| 195 | + if timeout: |
| 196 | + start = time.time() |
| 197 | + while self.is_open() and time.time() - start < timeout: |
| 198 | + self.update(timeout=(timeout - time.time() + start)) |
| 199 | + else: |
| 200 | + while self.is_open(): |
| 201 | + self.update(timeout=None) |
| 202 | + |
| 203 | + def close(self, **kwargs): |
| 204 | + """ |
| 205 | + close websocket connection. |
| 206 | + """ |
| 207 | + self._connected = False |
| 208 | + if self.sock: |
| 209 | + self.sock.close(**kwargs) |
| 210 | + |
| 211 | + |
| 212 | +WSResponse = collections.namedtuple('WSResponse', ['data']) |
| 213 | + |
| 214 | + |
| 215 | +def get_websocket_url(url): |
| 216 | + parsed_url = urlparse(url) |
| 217 | + parts = list(parsed_url) |
| 218 | + if parsed_url.scheme == 'http': |
| 219 | + parts[0] = 'ws' |
| 220 | + elif parsed_url.scheme == 'https': |
| 221 | + parts[0] = 'wss' |
| 222 | + return urlunparse(parts) |
| 223 | + |
| 224 | + |
| 225 | +def websocket_call(configuration, url, query_params, _request_timeout, |
| 226 | + _preload_content, headers): |
| 227 | + """An internal function to be called in api-client when a websocket |
| 228 | + connection is required.""" |
| 229 | + |
| 230 | + # Extract the command from the list of tuples |
| 231 | + commands = None |
| 232 | + for key, value in query_params: |
| 233 | + if key == 'command': |
| 234 | + commands = value |
| 235 | + break |
| 236 | + |
| 237 | + # drop command from query_params as we will be processing it separately |
| 238 | + query_params = [(key, value) for key, value in query_params if |
| 239 | + key != 'command'] |
| 240 | + |
| 241 | + # if we still have query params then encode them |
| 242 | + if query_params: |
| 243 | + url += '?' + urlencode(query_params) |
| 244 | + |
| 245 | + # tack on the actual command to execute at the end |
| 246 | + if isinstance(commands, list): |
| 247 | + for command in commands: |
| 248 | + url += "&command=%s&" % quote_plus(command) |
| 249 | + elif commands is not None: |
| 250 | + url += '&command=' + quote_plus(commands) |
| 251 | + |
| 252 | + try: |
| 253 | + client = WSClient(configuration, get_websocket_url(url), headers) |
| 254 | + if not _preload_content: |
| 255 | + return client |
| 256 | + client.run_forever(timeout=_request_timeout) |
| 257 | + return WSResponse('%s' % ''.join(client.read_all())) |
| 258 | + except (Exception, KeyboardInterrupt, SystemExit) as e: |
| 259 | + raise ApiException(status=0, reason=str(e)) |
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