Added a MinecraftServer.lookup method, converts a string to host/port (including SRV lookup)

This closes #12

.travis.yml

@@ -3,6 +3,6 @@ python:
   - 3.3
   - 2.7
 install:
-  - pip install -r requirements.txt --use-mirrors
+  - if [[ $TRAVIS_PYTHON_VERSION == 2* ]]; then pip install -r requirements/python2.txt --use-mirrors; fi
-  - pip install mock --use-mirrors
+  - if [[ $TRAVIS_PYTHON_VERSION == 3* ]]; then pip install -r requirements/python3.txt --use-mirrors; fi
 script: nosetests

README.md

@@ -2,7 +2,7 @@ mcstatus
 ========
 
 `mcstatus` provides an easy way to query Minecraft servers for any information they can expose.
-It provides two modes of access, `query` and `ping`, the differences of which are listed below in usage.
+It provides three modes of access (`query`, `status` and `ping`), the differences of which are listed below in usage.
 
 Usage
 -----
@@ -10,15 +10,21 @@ Usage
 ```python
 from mcstatus import MinecraftServer
 
-server = MinecraftServer("localhost", 25565)
+# If you know the host and port, you may skip this and use MinecraftServer("example.org", 1234)
+server = MinecraftServer.lookup("example.org:1234")
+
+# 'status' is supported by all Minecraft servers that are version 1.7 or higher.
+status = server.status()
+print("The server has {0} players and replied in {1} ms".format(status.players.online, status.latency))
 
 # 'ping' is supported by all Minecraft servers that are version 1.7 or higher.
-status, ping = server.ping_server()
+# It is included in a 'status' call, but is exposed separate if you do not require the additional info.
-print("The server has {0} players".format(status.players.online))
+latency = server.ping()
+print("The server replied in {0} ms".format(latency))
 
 # 'query' has to be enabled in a servers' server.properties file.
 # It may give more information than a ping, such as a full player list or mod information.
-query = server.query_server()
+query = server.query()
 print("The server has the following players online: {0}".format(", ".join(query.players.names)))
 ```
 

mcstatus/server.py

@@ -1,6 +1,7 @@
 from mcstatus.pinger import ServerPinger
 from mcstatus.protocol.connection import TCPSocketConnection, UDPSocketConnection
 from mcstatus.querier import ServerQuerier
+import dns.resolver
 
 
 class MinecraftServer:
@@ -8,6 +9,29 @@ class MinecraftServer:
         self.host = host
         self.port = port
 
+    @staticmethod
+    def lookup(address):
+        host = address
+        port = None
+        if ":" in address:
+            parts = address.split(":")
+            if len(parts) > 2:
+                raise ValueError("Invalid address '%s'" % address)
+            host = parts[0]
+            port = int(parts[1])
+        if port is None:
+            port = 25565
+            try:
+                answers = dns.resolver.query("_minecraft._tcp." + host, "SRV")
+                if len(answers):
+                    answer = answers[0]
+                    host = str(answer.target).rstrip(".")
+                    port = int(answer.port)
+            except Exception:
+                pass
+
+        return MinecraftServer(host, port)
+
     def ping(self, retries=3, **kwargs):
         attempt = 0
         connection = TCPSocketConnection((self.host, self.port))

mcstatus/tests/test_server.py

@@ -81,4 +81,42 @@ class TestMinecraftServer(TestCase):
             with patch("mcstatus.server.ServerQuerier") as querier:
                 querier.side_effect = [Exception, Exception, Exception]
                 self.assertRaises(Exception, self.server.query)
-                self.assertEqual(querier.call_count, 3)
+                self.assertEqual(querier.call_count, 3)
+
+    def test_by_address_no_srv(self):
+        with patch("dns.resolver.query") as query:
+            query.return_value = []
+            self.server = MinecraftServer.lookup("example.org")
+            query.assert_called_once_with("_minecraft._tcp.example.org", "SRV")
+        self.assertEqual(self.server.host, "example.org")
+        self.assertEqual(self.server.port, 25565)
+
+    def test_by_address_invalid_srv(self):
+        with patch("dns.resolver.query") as query:
+            query.side_effect = [Exception]
+            self.server = MinecraftServer.lookup("example.org")
+            query.assert_called_once_with("_minecraft._tcp.example.org", "SRV")
+        self.assertEqual(self.server.host, "example.org")
+        self.assertEqual(self.server.port, 25565)
+
+    def test_by_address_with_srv(self):
+        with patch("dns.resolver.query") as query:
+            answer = Mock()
+            answer.target = "different.example.org."
+            answer.port = 12345
+            query.return_value = [answer]
+            self.server = MinecraftServer.lookup("example.org")
+            query.assert_called_once_with("_minecraft._tcp.example.org", "SRV")
+        self.assertEqual(self.server.host, "different.example.org")
+        self.assertEqual(self.server.port, 12345)
+
+    def test_by_address_with_port(self):
+        self.server = MinecraftServer.lookup("example.org:12345")
+        self.assertEqual(self.server.host, "example.org")
+        self.assertEqual(self.server.port, 12345)
+
+    def test_by_address_with_multiple_ports(self):
+        self.assertRaises(ValueError, MinecraftServer.lookup, "example.org:12345:6789")
+
+    def test_by_address_with_invalid_port(self):
+        self.assertRaises(ValueError, MinecraftServer.lookup, "example.org:port")

requirements.txt

@@ -1 +1 @@
-six==1.7.3
+-r requirements/base.txt

requirements/base.txt

@@ -0,0 +1,2 @@
+six==1.7.3
+mock==1.0.1

requirements/python2.txt

@@ -0,0 +1,3 @@
+-r base.txt
+
+dnspython==1.12.0

requirements/python3.txt

@@ -0,0 +1,3 @@
+-r base.txt
+
+dnspython3==1.12.0

setup.py

@@ -1,4 +1,18 @@
 from distutils.core import setup
+from six import PY2
+
+install_requires = [
+    'six'
+]
+
+if PY2:
+    install_requires.append('dnspython')
+else:
+    install_requires.append('dnspython3')
+
+tests_require = [
+    'mock'
+]
 
 setup(
     name='mcstatus',
@@ -8,8 +22,8 @@ setup(
     url='https://pypi.python.org/pypi/mcstatus',
     packages=['mcstatus', 'mcstatus.protocol'],
     description='A library to query Minecraft Servers for their status and capabilities.',
-    install_requires=['six'],
+    install_requires=install_requires,
-    tests_require=['mock'],
+    tests_require=tests_require,
     classifiers=[
         'Development Status :: 5 - Production/Stable',
         'Intended Audience :: Developers',