implement a dyndns2 updater + tests

nsupdate/utils/_tests/test_ddns_client.py

@@ -0,0 +1,57 @@
+"""
+Tests for ddns_client module.
+"""
+
+import pytest
+
+from requests import Timeout, ConnectionError
+
+from ..ddns_client import dyndns2_update
+
+# see also conftest.py
+BASEDOMAIN = 'nsupdate.info'
+HOSTNAME = 'nsupdate-ddns-client-unittest.' + BASEDOMAIN
+INVALID_HOSTNAME = 'nsupdate-ddns-client-nohost.' + BASEDOMAIN
+USER, PASSWORD = HOSTNAME, 'yUTvxjRwNu'  # no problem, is only used for this unit test
+SERVER = 'ipv4.' + BASEDOMAIN
+SECURE = False  # SSL/SNI support on python 2.x sucks :(
+
+
+class TestDynDns2Client(object):
+    def test_timeout(self):
+        with pytest.raises(Timeout):
+            # this assumes that the service can't respond in 1us and thus times out
+            dyndns2_update('wrong', 'wrong', SERVER,
+                           hostname='wrong', myip='1.2.3.4', secure=SECURE,
+                           timeout=0.000001)
+
+    def test_connrefused(self):
+        with pytest.raises(ConnectionError):
+            # this assumes that there is no service running on 127.0.0.42
+            dyndns2_update('wrong', 'wrong', '127.0.0.42',
+                           hostname='wrong', myip='1.2.3.4', secure=SECURE,
+                           timeout=2.0)
+
+    def test_notfqdn(self):
+        status, text = dyndns2_update('wrongdomainnotfqdn', 'wrongpassword', SERVER,
+                                      hostname=HOSTNAME, myip='1.2.3.4', secure=SECURE)
+        assert status == 200
+        assert text == 'notfqdn'
+
+    def test_badauth(self):
+        status, text = dyndns2_update(USER, 'wrongpassword', SERVER,
+                                      hostname=HOSTNAME, myip='1.2.3.4', secure=SECURE)
+        assert status == 401
+
+    def test_nohost(self):
+        status, text = dyndns2_update(USER, PASSWORD, SERVER,
+                                      hostname=INVALID_HOSTNAME, myip='1.2.3.4', secure=SECURE)
+        assert status == 200
+        assert text == 'nohost'
+
+    def test_success(self):
+        ip = '1.2.3.4'
+        status, text = dyndns2_update(USER, PASSWORD, SERVER,
+                                      hostname=HOSTNAME, myip=ip, secure=SECURE)
+        assert status == 200
+        assert text in ["good %s" % ip, "nochg %s" % ip]

nsupdate/utils/ddns_client.py

@@ -0,0 +1,40 @@
+"""
+dyndns2 client
+"""
+
+import logging
+logger = logging.getLogger(__name__)
+
+import requests
+
+TIMEOUT = 30.0  # timeout for http request response [s]
+
+
+def dyndns2_update(userid, password,
+                   server, hostname=None, myip=None,
+                   path='/nic/update', secure=True, timeout=TIMEOUT):
+    """
+    send a dyndns2-compatible update request
+
+    :param userid: for http basic auth
+    :param password: for http basic auth
+    :param server: server to send the update to
+    :param hostname: hostname we want to update
+    :param myip: the new ip address for hostname
+    :param path: url path (default: '/nic/update')
+    :param secure: whether to use ssl for the request (default: True)
+                   note: if you use secure=False, it will transmit
+                   the given data unencrypted.
+    :param timeout: how long to wait until response has to begin
+    :return:
+    """
+    params = {}
+    if hostname is not None:
+        params['hostname'] = hostname
+    if myip is not None:
+        params['myip'] = myip
+    url = "%s://%s%s" % ('https' if secure else 'http', server, path)
+    r = requests.get(url, params=params, auth=(userid, password), timeout=timeout)
+    r.close()
+    logger.debug("update response: %d %s" % (r.status_code, r.text, ))
+    return r.status_code, r.text

setup.py

@@ -49,6 +49,7 @@ setup(
         'django-registration',
         'django-extensions',
         'python-social-auth',
+        'requests',  # for our ddns_client
         # packages only needed for development:
         'django-debug-toolbar',
         'pytest',