Add support for getaddrinfo

fixes #23

aiodns/__init__.py

@@ -110,6 +110,12 @@ def gethostbyname(self, host: str, family: socket.AddressFamily) -> asyncio.Futu
         cb = functools.partial(self._callback, fut)
         self._channel.gethostbyname(host, family, cb)
         return fut
+
+    def getaddrinfo(self, host: str, family: socket.AddressFamily = 0, port: Optional[int] = None, proto: int = 0, type: int = 0, flags: int = 0) -> asyncio.Future:
+        fut = asyncio.Future(loop=self.loop) # type: asyncio.Future
+        cb = functools.partial(self._callback, fut)
+        self._channel.getaddrinfo(host, port, cb, family=family, type=type, proto=proto, flags=flags)
+        return fut
 
     def gethostbyaddr(self, name: str) -> asyncio.Future:
         fut = asyncio.Future(loop=self.loop)  # type: asyncio.Future

tests.py

@@ -151,6 +151,26 @@ def test_gethostbyname(self):
         result = self.loop.run_until_complete(f)
         self.assertTrue(result)
 
+    def test_getaddrinfo_address_family_0(self):
+        f = self.resolver.getaddrinfo('google.com')
+        result = self.loop.run_until_complete(f)
+        self.assertTrue(result)
+        self.assertTrue(len(result.nodes) > 1)
+
+    def test_getaddrinfo_address_family_af_inet(self):
+        f = self.resolver.getaddrinfo('google.com', socket.AF_INET)
+        result = self.loop.run_until_complete(f)
+        self.assertTrue(result)
+        self.assertTrue(len(result.nodes) == 1)
+        self.assertTrue(result.nodes[0].family == socket.AF_INET)
+
+    def test_getaddrinfo_address_family_af_inet6(self):
+        f = self.resolver.getaddrinfo('google.com', socket.AF_INET6)
+        result = self.loop.run_until_complete(f)
+        self.assertTrue(result)
+        self.assertTrue(len(result.nodes) == 1)
+        self.assertTrue(result.nodes[0].family == socket.AF_INET6)
+
     @unittest.skipIf(sys.platform == 'win32', 'skipped on Windows')
     def test_gethostbyaddr(self):
         f = self.resolver.gethostbyaddr('127.0.0.1')