Merge pull request #36 from hasgeek/namespace_from_url

Added namespace_from_url()

coaster/utils.py

@@ -12,6 +12,7 @@
 from warnings import warn
 from BeautifulSoup import BeautifulSoup, Comment
 import pytz
+from urlparse import urlparse
 
 from ._version import *
 
@@ -22,6 +23,7 @@
 _punctuation_re = re.compile(ur'[\t +!#$%&()*\-/<=>?@\[\\\]^_{|}:;,.…‒–—―«»]+')
 _diacritics_re = re.compile(u'[\u0300-\u036F]+')
 _username_valid_re = re.compile('^[a-z0-9]([a-z0-9-]*[a-z0-9])?$')
+_ipv4_re = re.compile('^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$')
 
 
 # --- Utilities ---------------------------------------------------------------
@@ -453,6 +455,24 @@ def hourmin(delta):
         ) for delta, name in timezones]
 
 
+def namespace_from_url(url):
+    """
+    Construct a dotted namespace string from a URL.
+    """
+    parsed = urlparse(url)
+    if parsed.hostname is None or parsed.hostname in ['localhost', 'localhost.localdomain'] or (
+            _ipv4_re.search(parsed.hostname)):
+        return None
+
+    namespace = parsed.hostname.split('.')
+    namespace.reverse()
+    if namespace and not namespace[0]:
+        namespace.pop(0)
+    if namespace and namespace[-1] == 'www':
+        namespace.pop(-1)
+    return '.'.join(namespace)
+
+
 class LabeledEnum(object):
     """
     Labeled enumerations. Declarate an enumeration with values and labels

tests/test_utils.py

@@ -2,7 +2,7 @@
 
 import datetime
 import unittest
-from coaster.utils import LabeledEnum, make_password, check_password, parse_isoformat, sanitize_html, sorted_timezones
+from coaster.utils import LabeledEnum, make_password, check_password, parse_isoformat, sanitize_html, sorted_timezones, namespace_from_url
 
 
 class MY_ENUM(LabeledEnum):
@@ -49,3 +49,16 @@ def test_sanitize_html(self):
 
     def test_sorted_timezones(self):
         self.assertTrue(isinstance(sorted_timezones(), list))
+
+    def test_namespace_from_url(self):
+        self.assertEqual(namespace_from_url(u'https://github.com/hasgeek/coaster'), u'com.github')
+        self.assertEqual(namespace_from_url(u'https://funnel.hasgeek.com/metarefresh2014/938-making-design-decisions'),
+            u'com.hasgeek.funnel')
+        self.assertEqual(namespace_from_url(u'http://www.hasgeek.com'), u'com.hasgeek')
+        self.assertEqual(namespace_from_url(u'www.hasgeek.com'), None)
+        self.assertEqual(namespace_from_url(u'This is an invalid url'), None)
+        # IP addresses are rejected
+        self.assertEqual(namespace_from_url('127.0.0.1'), None)
+        # Return string type is the input type
+        self.assertTrue(isinstance(namespace_from_url(u'https://github.com/hasgeek/coaster'), unicode))
+        self.assertTrue(isinstance(namespace_from_url('https://github.com/hasgeek/coaster'), str))