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@@ -1,458 +1,466 b'' | |||
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1 | 1 | """Kernel frontend classes. |
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2 | 2 | |
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3 | 3 | TODO: Create logger to handle debugging and console messages. |
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4 | 4 | |
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5 | 5 | """ |
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6 | 6 | |
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7 | 7 | # Standard library imports. |
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8 | 8 | from Queue import Queue, Empty |
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9 | 9 | from subprocess import Popen |
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10 | 10 | from threading import Thread |
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11 | 11 | import time |
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12 | 12 | import traceback |
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13 | 13 | |
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14 | 14 | # System library imports. |
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15 | 15 | import zmq |
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16 | 16 | from zmq import POLLIN, POLLOUT, POLLERR |
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17 | 17 | from zmq.eventloop import ioloop |
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18 | 18 | |
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19 | 19 | # Local imports. |
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20 | 20 | from IPython.utils.traitlets import HasTraits, Any, Bool, Int, Instance, Str, \ |
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21 | 21 | Type |
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22 | 22 | from kernel import launch_kernel |
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23 | 23 | from session import Session |
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24 | 24 | |
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25 | 25 | # Constants. |
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26 | 26 | LOCALHOST = '127.0.0.1' |
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27 | 27 | |
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28 | 28 | |
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29 | 29 | class MissingHandlerError(Exception): |
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30 | 30 | pass |
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31 | 31 | |
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32 | 32 | |
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33 | 33 | class ZmqSocketChannel(Thread): |
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34 | 34 | """ The base class for the channels that use ZMQ sockets. |
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35 | 35 | """ |
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36 | 36 | |
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37 | 37 | def __init__(self, context, session, address=None): |
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38 | 38 | super(ZmqSocketChannel, self).__init__() |
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39 | 39 | self.daemon = True |
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40 | 40 | |
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41 | 41 | self.context = context |
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42 | 42 | self.session = session |
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43 | 43 | self.address = address |
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44 | 44 | self.socket = None |
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45 | 45 | |
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46 | 46 | def stop(self): |
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47 | 47 | """Stop the thread's activity. Returns when the thread terminates. |
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48 | 48 | |
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49 | 49 | The thread will raise :class:`RuntimeError` if :method:`self.start` |
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50 | 50 | is called again. |
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51 | 51 | """ |
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52 | 52 | self.join() |
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53 | 53 | |
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54 | 54 | |
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55 | 55 | def get_address(self): |
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56 | 56 | """ Get the channel's address. By the default, a channel is on |
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57 | 57 | localhost with no port specified (a negative port number). |
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58 | 58 | """ |
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59 | 59 | return self._address |
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60 | 60 | |
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61 | 61 | def set_adresss(self, address): |
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62 | 62 | """ Set the channel's address. Should be a tuple of form: |
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63 | 63 | (ip address [str], port [int]). |
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64 | 64 | or None, in which case the address is reset to its default value. |
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65 | 65 | """ |
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66 | 66 | # FIXME: Validate address. |
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67 | 67 | if self.is_alive(): # This is Thread.is_alive |
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68 | 68 | raise RuntimeError("Cannot set address on a running channel!") |
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69 | 69 | else: |
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70 | 70 | if address is None: |
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71 | 71 | address = (LOCALHOST, 0) |
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72 | 72 | self._address = address |
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73 | 73 | |
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74 | 74 | address = property(get_address, set_adresss) |
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75 | 75 | |
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76 | 76 | |
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77 | 77 | class SubSocketChannel(ZmqSocketChannel): |
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78 | 78 | |
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79 | 79 | def __init__(self, context, session, address=None): |
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80 | 80 | super(SubSocketChannel, self).__init__(context, session, address) |
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81 | 81 | |
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82 | 82 | def run(self): |
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83 | 83 | self.socket = self.context.socket(zmq.SUB) |
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84 | 84 | self.socket.setsockopt(zmq.SUBSCRIBE,'') |
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85 | 85 | self.socket.setsockopt(zmq.IDENTITY, self.session.session) |
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86 | 86 | self.socket.connect('tcp://%s:%i' % self.address) |
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87 | 87 | self.ioloop = ioloop.IOLoop() |
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88 | 88 | self.ioloop.add_handler(self.socket, self._handle_events, |
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89 | 89 | POLLIN|POLLERR) |
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90 | 90 | self.ioloop.start() |
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91 | 91 | |
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92 | 92 | def stop(self): |
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93 | 93 | self.ioloop.stop() |
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94 | 94 | super(SubSocketChannel, self).stop() |
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95 | 95 | |
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96 | 96 | def _handle_events(self, socket, events): |
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97 | 97 | # Turn on and off POLLOUT depending on if we have made a request |
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98 | 98 | if events & POLLERR: |
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99 | 99 | self._handle_err() |
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100 | 100 | if events & POLLIN: |
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101 | 101 | self._handle_recv() |
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102 | 102 | |
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103 | 103 | def _handle_err(self): |
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104 | 104 | # We don't want to let this go silently, so eventually we should log. |
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105 |
raise zmq.Z |
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105 | raise zmq.ZMQError() | |
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106 | 106 | |
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107 | 107 | def _handle_recv(self): |
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108 | msg = self.socket.recv_json() | |
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109 | self.call_handlers(msg) | |
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108 | # Get all of the messages we can | |
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109 | while True: | |
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110 | try: | |
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111 | msg = self.socket.recv_json(zmq.NOBLOCK) | |
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112 | except zmq.ZMQError: | |
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113 | # Check the errno? | |
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114 | # Will this tigger POLLERR? | |
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115 | break | |
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116 | else: | |
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117 | self.call_handlers(msg) | |
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110 | 118 | |
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111 | 119 | def call_handlers(self, msg): |
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112 | 120 | """This method is called in the ioloop thread when a message arrives. |
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113 | 121 | |
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114 | 122 | Subclasses should override this method to handle incoming messages. |
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115 | 123 | It is important to remember that this method is called in the thread |
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116 | 124 | so that some logic must be done to ensure that the application leve |
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117 | 125 | handlers are called in the application thread. |
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118 | 126 | """ |
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119 | 127 | raise NotImplementedError('call_handlers must be defined in a subclass.') |
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120 | 128 | |
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121 | 129 | def flush(self, timeout=1.0): |
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122 | 130 | """Immediately processes all pending messages on the SUB channel. |
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123 | 131 | |
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124 | 132 | This method is thread safe. |
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125 | 133 | |
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126 | 134 | Parameters |
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127 | 135 | ---------- |
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128 | 136 | timeout : float, optional |
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129 | 137 | The maximum amount of time to spend flushing, in seconds. The |
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130 | 138 | default is one second. |
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131 | 139 | """ |
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132 | 140 | # We do the IOLoop callback process twice to ensure that the IOLoop |
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133 | 141 | # gets to perform at least one full poll. |
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134 | 142 | stop_time = time.time() + timeout |
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135 | 143 | for i in xrange(2): |
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136 | 144 | self._flushed = False |
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137 | 145 | self.ioloop.add_callback(self._flush) |
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138 | 146 | while not self._flushed and time.time() < stop_time: |
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139 | 147 | time.sleep(0.01) |
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140 | 148 | |
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141 | 149 | def _flush(self): |
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142 | 150 | """Called in this thread by the IOLoop to indicate that all events have |
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143 | 151 | been processed. |
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144 | 152 | """ |
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145 | 153 | self._flushed = True |
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146 | 154 | |
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147 | 155 | |
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148 | 156 | class XReqSocketChannel(ZmqSocketChannel): |
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149 | 157 | |
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150 | 158 | handler_queue = None |
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151 | 159 | command_queue = None |
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152 | 160 | handlers = None |
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153 | 161 | _overriden_call_handler = None |
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154 | 162 | |
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155 | 163 | def __init__(self, context, session, address=None): |
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156 | 164 | self.handlers = {} |
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157 | 165 | self.handler_queue = Queue() |
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158 | 166 | self.command_queue = Queue() |
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159 | 167 | super(XReqSocketChannel, self).__init__(context, session, address) |
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160 | 168 | |
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161 | 169 | def run(self): |
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162 | 170 | self.socket = self.context.socket(zmq.XREQ) |
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163 | 171 | self.socket.setsockopt(zmq.IDENTITY, self.session.session) |
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164 | 172 | self.socket.connect('tcp://%s:%i' % self.address) |
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165 | 173 | self.ioloop = ioloop.IOLoop() |
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166 | 174 | self.ioloop.add_handler(self.socket, self._handle_events, |
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167 | 175 | POLLIN|POLLOUT|POLLERR) |
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168 | 176 | self.ioloop.start() |
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169 | 177 | |
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170 | 178 | def stop(self): |
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171 | 179 | self.ioloop.stop() |
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172 | 180 | super(XReqSocketChannel, self).stop() |
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173 | 181 | |
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174 | 182 | def _handle_events(self, socket, events): |
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175 | 183 | # Turn on and off POLLOUT depending on if we have made a request |
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176 | 184 | if events & POLLERR: |
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177 | 185 | self._handle_err() |
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178 | 186 | if events & POLLOUT: |
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179 | 187 | self._handle_send() |
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180 | 188 | if events & POLLIN: |
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181 | 189 | self._handle_recv() |
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182 | 190 | |
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183 | 191 | def _handle_recv(self): |
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184 | 192 | msg = self.socket.recv_json() |
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185 | 193 | self.call_handlers(msg) |
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186 | 194 | |
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187 | 195 | def _handle_send(self): |
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188 | 196 | try: |
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189 | 197 | msg = self.command_queue.get(False) |
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190 | 198 | except Empty: |
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191 | 199 | pass |
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192 | 200 | else: |
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193 | 201 | self.socket.send_json(msg) |
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194 | 202 | |
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195 | 203 | def _handle_err(self): |
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196 | 204 | # We don't want to let this go silently, so eventually we should log. |
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197 |
raise zmq.Z |
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205 | raise zmq.ZMQError() | |
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198 | 206 | |
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199 | 207 | def _queue_request(self, msg, callback): |
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200 | 208 | handler = self._find_handler(msg['msg_type'], callback) |
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201 | 209 | self.handler_queue.put(handler) |
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202 | 210 | self.command_queue.put(msg) |
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203 | 211 | |
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204 | 212 | def execute(self, code, callback=None): |
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205 | 213 | # Create class for content/msg creation. Related to, but possibly |
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206 | 214 | # not in Session. |
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207 | 215 | content = dict(code=code) |
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208 | 216 | msg = self.session.msg('execute_request', content) |
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209 | 217 | self._queue_request(msg, callback) |
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210 | 218 | return msg['header']['msg_id'] |
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211 | 219 | |
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212 | 220 | def complete(self, text, line, block=None, callback=None): |
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213 | 221 | content = dict(text=text, line=line) |
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214 | 222 | msg = self.session.msg('complete_request', content) |
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215 | 223 | self._queue_request(msg, callback) |
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216 | 224 | return msg['header']['msg_id'] |
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217 | 225 | |
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218 | 226 | def object_info(self, oname, callback=None): |
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219 | 227 | content = dict(oname=oname) |
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220 | 228 | msg = self.session.msg('object_info_request', content) |
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221 | 229 | self._queue_request(msg, callback) |
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222 | 230 | return msg['header']['msg_id'] |
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223 | 231 | |
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224 | 232 | def _find_handler(self, name, callback): |
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225 | 233 | if callback is not None: |
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226 | 234 | return callback |
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227 | 235 | handler = self.handlers.get(name) |
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228 | 236 | if handler is None: |
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229 | 237 | raise MissingHandlerError( |
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230 | 238 | 'No handler defined for method: %s' % name) |
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231 | 239 | return handler |
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232 | 240 | |
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233 | 241 | def override_call_handler(self, func): |
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234 | 242 | """Permanently override the call_handler. |
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235 | 243 | |
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236 | 244 | The function func will be called as:: |
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237 | 245 | |
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238 | 246 | func(handler, msg) |
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239 | 247 | |
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240 | 248 | And must call:: |
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241 | 249 | |
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242 | 250 | handler(msg) |
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243 | 251 | |
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244 | 252 | in the main thread. |
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245 | 253 | """ |
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246 | 254 | assert callable(func), "not a callable: %r" % func |
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247 | 255 | self._overriden_call_handler = func |
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248 | 256 | |
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249 | 257 | def call_handlers(self, msg): |
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250 | 258 | try: |
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251 | 259 | handler = self.handler_queue.get(False) |
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252 | 260 | except Empty: |
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253 | 261 | print "Message received with no handler!!!" |
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254 | 262 | print msg |
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255 | 263 | else: |
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256 | 264 | self.call_handler(handler, msg) |
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257 | 265 | |
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258 | 266 | def call_handler(self, handler, msg): |
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259 | 267 | if self._overriden_call_handler is not None: |
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260 | 268 | self._overriden_call_handler(handler, msg) |
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261 | 269 | elif hasattr(self, '_call_handler'): |
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262 | 270 | call_handler = getattr(self, '_call_handler') |
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263 | 271 | call_handler(handler, msg) |
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264 | 272 | else: |
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265 | 273 | raise RuntimeError('no handler!') |
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266 | 274 | |
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267 | 275 | |
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268 | 276 | class RepSocketChannel(ZmqSocketChannel): |
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269 | 277 | |
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270 | 278 | def on_raw_input(self): |
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271 | 279 | pass |
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272 | 280 | |
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273 | 281 | |
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274 | 282 | class KernelManager(HasTraits): |
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275 | 283 | """ Manages a kernel for a frontend. |
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276 | 284 | |
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277 | 285 | The SUB channel is for the frontend to receive messages published by the |
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278 | 286 | kernel. |
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279 | 287 | |
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280 | 288 | The REQ channel is for the frontend to make requests of the kernel. |
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281 | 289 | |
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282 | 290 | The REP channel is for the kernel to request stdin (raw_input) from the |
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283 | 291 | frontend. |
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284 | 292 | """ |
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285 | 293 | |
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286 | 294 | # Whether the kernel manager is currently listening on its channels. |
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287 | 295 | is_listening = Bool(False) |
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288 | 296 | |
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289 | 297 | # The PyZMQ Context to use for communication with the kernel. |
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290 | 298 | context = Instance(zmq.Context, ()) |
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291 | 299 | |
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292 | 300 | # The Session to use for communication with the kernel. |
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293 | 301 | session = Instance(Session, ()) |
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294 | 302 | |
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295 | 303 | # The classes to use for the various channels. |
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296 | 304 | sub_channel_class = Type(SubSocketChannel) |
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297 | 305 | xreq_channel_class = Type(XReqSocketChannel) |
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298 | 306 | rep_channel_class = Type(RepSocketChannel) |
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299 | 307 | |
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300 | 308 | # Protected traits. |
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301 | 309 | _kernel = Instance(Popen) |
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302 | 310 | _sub_channel = Any |
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303 | 311 | _xreq_channel = Any |
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304 | 312 | _rep_channel = Any |
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305 | 313 | |
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306 | 314 | #-------------------------------------------------------------------------- |
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307 | 315 | # Channel management methods: |
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308 | 316 | #-------------------------------------------------------------------------- |
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309 | 317 | |
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310 | 318 | def start_listening(self): |
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311 | 319 | """Starts listening on the specified ports. If already listening, raises |
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312 | 320 | a RuntimeError. |
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313 | 321 | """ |
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314 | 322 | if self.is_listening: |
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315 | 323 | raise RuntimeError("Cannot start listening. Already listening!") |
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316 | 324 | else: |
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317 | 325 | self.is_listening = True |
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318 | 326 | self.sub_channel.start() |
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319 | 327 | self.xreq_channel.start() |
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320 | 328 | self.rep_channel.start() |
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321 | 329 | |
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322 | 330 | @property |
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323 | 331 | def is_alive(self): |
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324 | 332 | """ Returns whether the kernel is alive. """ |
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325 | 333 | if self.is_listening: |
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326 | 334 | # TODO: check if alive. |
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327 | 335 | return True |
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328 | 336 | else: |
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329 | 337 | return False |
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330 | 338 | |
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331 | 339 | def stop_listening(self): |
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332 | 340 | """Stops listening. If not listening, does nothing. """ |
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333 | 341 | if self.is_listening: |
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334 | 342 | self.is_listening = False |
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335 | 343 | self.sub_channel.stop() |
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336 | 344 | self.xreq_channel.stop() |
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337 | 345 | self.rep_channel.stop() |
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338 | 346 | |
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339 | 347 | #-------------------------------------------------------------------------- |
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340 | 348 | # Kernel process management methods: |
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341 | 349 | #-------------------------------------------------------------------------- |
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342 | 350 | |
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343 | 351 | def start_kernel(self): |
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344 | 352 | """Starts a kernel process and configures the manager to use it. |
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345 | 353 | |
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346 | 354 | If ports have been specified via the address attributes, they are used. |
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347 | 355 | Otherwise, open ports are chosen by the OS and the channel port |
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348 | 356 | attributes are configured as appropriate. |
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349 | 357 | """ |
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350 | 358 | xreq, sub = self.xreq_address, self.sub_address |
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351 | 359 | if xreq[0] != LOCALHOST or sub[0] != LOCALHOST: |
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352 | 360 | raise RuntimeError("Can only launch a kernel on localhost." |
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353 | 361 | "Make sure that the '*_address' attributes are " |
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354 | 362 | "configured properly.") |
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355 | 363 | |
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356 | 364 | kernel, xrep, pub = launch_kernel(xrep_port=xreq[1], pub_port=sub[1]) |
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357 | 365 | self.set_kernel(kernel) |
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358 | 366 | self.xreq_address = (LOCALHOST, xrep) |
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359 | 367 | self.sub_address = (LOCALHOST, pub) |
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360 | 368 | |
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361 | 369 | def set_kernel(self, kernel): |
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362 | 370 | """Sets the kernel manager's kernel to an existing kernel process. |
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363 | 371 | |
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364 | 372 | It is *not* necessary to a set a kernel to communicate with it via the |
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365 | 373 | channels, and those objects must be configured separately. It |
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366 | 374 | *is* necessary to set a kernel if you want to use the manager (or |
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367 | 375 | frontends that use the manager) to signal and/or kill the kernel. |
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368 | 376 | |
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369 | 377 | Parameters: |
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370 | 378 | ----------- |
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371 | 379 | kernel : Popen |
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372 | 380 | An existing kernel process. |
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373 | 381 | """ |
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374 | 382 | self._kernel = kernel |
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375 | 383 | |
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376 | 384 | @property |
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377 | 385 | def has_kernel(self): |
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378 | 386 | """Returns whether a kernel process has been specified for the kernel |
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379 | 387 | manager. |
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380 | 388 | |
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381 | 389 | A kernel process can be set via 'start_kernel' or 'set_kernel'. |
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382 | 390 | """ |
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383 | 391 | return self._kernel is not None |
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384 | 392 | |
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385 | 393 | def kill_kernel(self): |
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386 | 394 | """ Kill the running kernel. """ |
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387 | 395 | if self._kernel: |
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388 | 396 | self._kernel.kill() |
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389 | 397 | self._kernel = None |
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390 | 398 | else: |
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391 | 399 | raise RuntimeError("Cannot kill kernel. No kernel is running!") |
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392 | 400 | |
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393 | 401 | def signal_kernel(self, signum): |
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394 | 402 | """ Sends a signal to the kernel. """ |
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395 | 403 | if self._kernel: |
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396 | 404 | self._kernel.send_signal(signum) |
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397 | 405 | else: |
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398 | 406 | raise RuntimeError("Cannot signal kernel. No kernel is running!") |
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399 | 407 | |
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400 | 408 | #-------------------------------------------------------------------------- |
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401 | 409 | # Channels used for communication with the kernel: |
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402 | 410 | #-------------------------------------------------------------------------- |
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403 | 411 | |
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404 | 412 | @property |
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405 | 413 | def sub_channel(self): |
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406 | 414 | """Get the SUB socket channel object.""" |
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407 | 415 | if self._sub_channel is None: |
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408 | 416 | self._sub_channel = self.sub_channel_class(self.context, |
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409 | 417 | self.session) |
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410 | 418 | return self._sub_channel |
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411 | 419 | |
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412 | 420 | @property |
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413 | 421 | def xreq_channel(self): |
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414 | 422 | """Get the REQ socket channel object to make requests of the kernel.""" |
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415 | 423 | if self._xreq_channel is None: |
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416 | 424 | self._xreq_channel = self.xreq_channel_class(self.context, |
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417 | 425 | self.session) |
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418 | 426 | return self._xreq_channel |
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419 | 427 | |
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420 | 428 | @property |
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421 | 429 | def rep_channel(self): |
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422 | 430 | """Get the REP socket channel object to handle stdin (raw_input).""" |
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423 | 431 | if self._rep_channel is None: |
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424 | 432 | self._rep_channel = self.rep_channel_class(self.context, |
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425 | 433 | self.session) |
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426 | 434 | return self._rep_channel |
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427 | 435 | |
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428 | 436 | #-------------------------------------------------------------------------- |
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429 | 437 | # Delegates for the Channel address attributes: |
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430 | 438 | #-------------------------------------------------------------------------- |
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431 | 439 | |
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432 | 440 | def get_sub_address(self): |
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433 | 441 | return self.sub_channel.address |
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434 | 442 | |
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435 | 443 | def set_sub_address(self, address): |
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436 | 444 | self.sub_channel.address = address |
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437 | 445 | |
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438 | 446 | sub_address = property(get_sub_address, set_sub_address, |
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439 | 447 | doc="The address used by SUB socket channel.") |
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440 | 448 | |
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441 | 449 | def get_xreq_address(self): |
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442 | 450 | return self.xreq_channel.address |
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443 | 451 | |
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444 | 452 | def set_xreq_address(self, address): |
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445 | 453 | self.xreq_channel.address = address |
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446 | 454 | |
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447 | 455 | xreq_address = property(get_xreq_address, set_xreq_address, |
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448 | 456 | doc="The address used by XREQ socket channel.") |
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449 | 457 | |
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450 | 458 | def get_rep_address(self): |
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451 | 459 | return self.rep_channel.address |
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452 | 460 | |
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453 | 461 | def set_rep_address(self, address): |
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454 | 462 | self.rep_channel.address = address |
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455 | 463 | |
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456 | 464 | rep_address = property(get_rep_address, set_rep_address, |
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457 | 465 | doc="The address used by REP socket channel.") |
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458 | 466 |
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