From 82479dfc1899acfcc7f7a34bed69f3513cdd8b35 Mon Sep 17 00:00:00 2001
From: Nicolas Jouanin <nico@beerfactory.org>
Date: Thu, 18 Jun 2015 10:22:46 +0200
Subject: [PATCH] Add Unsuscribe packet

---
 hbmqtt/mqtt/unsubscribe.py     | 48 ++++++++++++++++++++++++++++++++++
 tests/mqtt/test_unsubscribe.py | 29 ++++++++++++++++++++
 2 files changed, 77 insertions(+)
 create mode 100644 hbmqtt/mqtt/unsubscribe.py
 create mode 100644 tests/mqtt/test_unsubscribe.py

diff --git a/hbmqtt/mqtt/unsubscribe.py b/hbmqtt/mqtt/unsubscribe.py
new file mode 100644
index 0000000..ef7724c
--- /dev/null
+++ b/hbmqtt/mqtt/unsubscribe.py
@@ -0,0 +1,48 @@
+# Copyright (c) 2015 Nicolas JOUANIN
+#
+# See the file license.txt for copying permission.
+from hbmqtt.mqtt.packet import MQTTPacket, MQTTFixedHeader, PacketType, PacketIdVariableHeader, MQTTPayload, MQTTVariableHeader
+from hbmqtt.errors import HBMQTTException
+from hbmqtt.codecs import *
+
+
+class UnubscribePayload(MQTTPayload):
+    def __init__(self, topics=[]):
+        super().__init__()
+        self.topics = topics
+
+    def to_bytes(self, fixed_header: MQTTFixedHeader, variable_header: MQTTVariableHeader):
+        out = b''
+        for topic in self.topics:
+            out += encode_string(topic)
+        return out
+
+    @classmethod
+    @asyncio.coroutine
+    def from_stream(cls, reader: asyncio.StreamReader, fixed_header: MQTTFixedHeader,
+                    variable_header: MQTTVariableHeader):
+        topics = []
+        while True:
+            try:
+                topic = yield from decode_string(reader)
+                topics.append(topic)
+            except NoDataException:
+                break
+        return cls(topics)
+
+
+class UnsubscribePacket(MQTTPacket):
+    VARIABLE_HEADER = PacketIdVariableHeader
+    PAYLOAD = UnubscribePayload
+
+    def __init__(self, fixed: MQTTFixedHeader=None, variable_header: PacketIdVariableHeader=None, payload=None):
+        if fixed is None:
+            header = MQTTFixedHeader(PacketType.UNSUBSCRIBE, 0x00)
+        else:
+            if fixed.packet_type is not PacketType.UNSUBSCRIBE:
+                raise HBMQTTException("Invalid fixed packet type %s for UnsubscribePacket init" % fixed.packet_type)
+            header = fixed
+
+        super().__init__(header)
+        self.variable_header = variable_header
+        self.payload = payload
diff --git a/tests/mqtt/test_unsubscribe.py b/tests/mqtt/test_unsubscribe.py
new file mode 100644
index 0000000..274da6d
--- /dev/null
+++ b/tests/mqtt/test_unsubscribe.py
@@ -0,0 +1,29 @@
+# Copyright (c) 2015 Nicolas JOUANIN
+#
+# See the file license.txt for copying permission.
+import unittest
+
+from hbmqtt.mqtt.unsubscribe import UnsubscribePacket, UnubscribePayload
+from hbmqtt.mqtt.packet import PacketIdVariableHeader
+from hbmqtt.codecs import *
+
+class SubscribePacketTest(unittest.TestCase):
+    def setUp(self):
+        self.loop = asyncio.new_event_loop()
+
+    def test_from_stream(self):
+        data = b'\xa0\x0c\x00\n\x00\x03a/b\x00\x03c/d'
+        stream = asyncio.StreamReader(loop=self.loop)
+        stream.feed_data(data)
+        stream.feed_eof()
+        message = self.loop.run_until_complete(UnsubscribePacket.from_stream(stream))
+        self.assertEqual(message.payload.topics[0], 'a/b')
+        self.assertEqual(message.payload.topics[1], 'c/d')
+
+    def test_to_stream(self):
+        variable_header = PacketIdVariableHeader(10)
+        payload = UnubscribePayload(['a/b', 'c/d'])
+        publish = UnsubscribePacket(variable_header=variable_header, payload=payload)
+        out = publish.to_bytes()
+        print(out)
+        self.assertEqual(out, b'\xa0\x0c\x00\n\x00\x03a/b\x00\x03c/d')
\ No newline at end of file