1#
2# Licensed to the Apache Software Foundation (ASF) under one
3# or more contributor license agreements. See the NOTICE file
4# distributed with this work for additional information
5# regarding copyright ownership. The ASF licenses this file
6# to you under the Apache License, Version 2.0 (the
7# "License"); you may not use this file except in compliance
8# with the License. You may obtain a copy of the License at
9#
10#   http://www.apache.org/licenses/LICENSE-2.0
11#
12# Unless required by applicable law or agreed to in writing,
13# software distributed under the License is distributed on an
14# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15# KIND, either express or implied. See the License for the
16# specific language governing permissions and limitations
17# under the License.
18#
19import zmq
20from cStringIO import StringIO
21from thrift.transport.TTransport import TTransportBase, CReadableTransport
22
23
24class TZmqClient(TTransportBase, CReadableTransport):
25    def __init__(self, ctx, endpoint, sock_type):
26        self._sock = ctx.socket(sock_type)
27        self._endpoint = endpoint
28        self._wbuf = StringIO()
29        self._rbuf = StringIO()
30
31    def open(self):
32        self._sock.connect(self._endpoint)
33
34    def read(self, size):
35        ret = self._rbuf.read(size)
36        if len(ret) != 0:
37            return ret
38        self._read_message()
39        return self._rbuf.read(size)
40
41    def _read_message(self):
42        msg = self._sock.recv()
43        self._rbuf = StringIO(msg)
44
45    def write(self, buf):
46        self._wbuf.write(buf)
47
48    def flush(self):
49        msg = self._wbuf.getvalue()
50        self._wbuf = StringIO()
51        self._sock.send(msg)
52
53    # Implement the CReadableTransport interface.
54    @property
55    def cstringio_buf(self):
56        return self._rbuf
57
58    # NOTE: This will probably not actually work.
59    def cstringio_refill(self, prefix, reqlen):
60        while len(prefix) < reqlen:
61            self.read_message()
62            prefix += self._rbuf.getvalue()
63        self._rbuf = StringIO(prefix)
64        return self._rbuf
65