Added ipaddress objects conversion

Close #387

NEWS

@@ -19,8 +19,9 @@ New features:
 - The attributes `~connection.notices` and `~connection.notifies` can be
   customized replacing them with any object exposing an `!append()` method
   (:ticket:`#326`).
-- old ``inet`` adapters deprecated, but arrays of network types converted
+- Adapt network types to `ipaddress` objects when available. When not
-  to lists by default (:tickets:`#343, #387`).
+  enabled, convert arrays of network types to lists by default. The old `!Inet`
+  adapter is deprecated (:tickets:`#317, #343, #387`).
 - Added `~psycopg2.extensions.quote_ident()` function (:ticket:`#359`).
 - Added `~connection.get_dsn_parameters()` connection method (:ticket:`#364`).
 

doc/src/conf.py

@@ -62,7 +62,7 @@ except ImportError:
 
 intersphinx_mapping = {
     'py': ('http://docs.python.org/', None),
-    'py3': ('http://docs.python.org/3.2', None),
+    'py3': ('http://docs.python.org/3.4', None),
     }
 
 # Pattern to generate links to the bug tracker

doc/src/extras.rst

@@ -933,18 +933,27 @@ UUID data type
     pair: CIDR; Data types
     pair: MACADDR; Data types
 
-Networking data type
+.. _adapt-network:
-^^^^^^^^^^^^^^^^^^^^
 
-Psycopg casts the PostgreSQL networking data types (:sql:`inet`, :sql:`cidr`,
+Networking data types
-:sql:`macaddr`) into ordinary strings. However their array are detected as
+^^^^^^^^^^^^^^^^^^^^^
-arrays and directly cast into lists.
+
+By default Psycopg casts the PostgreSQL networking data types (:sql:`inet`,
+:sql:`cidr`, :sql:`macaddr`) into ordinary strings; array of such types are
+converted into lists of strings.
 
 .. versionchanged:: 2.7
-    in previous version array of networking types were not treated as arrays
+    in previous version array of networking types were not treated as arrays.
+
+.. autofunction:: register_ipaddress
+
 
 .. autofunction:: register_inet
 
+    .. deprecated:: 2.7
+        this function will not receive further development and disappear in
+        future versions.
+
 .. doctest::
 
     >>> psycopg2.extras.register_inet()
@@ -957,16 +966,12 @@ arrays and directly cast into lists.
     >>> cur.fetchone()[0].addr
     '192.168.0.1/24'
 
-.. deprecated:: 2.7
-    this function will not receive further development and disappear in future
-    versions
-
 
 .. autoclass:: Inet
 
     .. deprecated:: 2.7
-    this object will not receive further development and disappear in future
+        this object will not receive further development and may disappear in
-    versions
+        future versions.
 
 
 .. index::

doc/src/usage.rst

@@ -264,7 +264,10 @@ types:
     +--------------------+-------------------------+--------------------------+
     | Anything\ |tm|     | :sql:`json`             | :ref:`adapt-json`        |
     +--------------------+-------------------------+--------------------------+
-    | `uuid`             | :sql:`uuid`             | :ref:`adapt-uuid`        |
+    | `~uuid.UUID`       | :sql:`uuid`             | :ref:`adapt-uuid`        |
+    +--------------------+-------------------------+--------------------------+
+    | `ipaddress`        | | :sql:`inet`           | :ref:`adapt-network`     |
+    | objects            | | :sql:`cidr`           |                          |
     +--------------------+-------------------------+--------------------------+
 
 .. |tm| unicode:: U+2122

lib/_ipaddress.py

@@ -0,0 +1,89 @@
+"""Implementation of the ipaddres-based network types adaptation
+"""
+
+# psycopg/_ipaddress.py - Ipaddres-based network types adaptation
+#
+# Copyright (C) 2016 Daniele Varrazzo  <daniele.varrazzo@gmail.com>
+#
+# psycopg2 is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License as published
+# by the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# In addition, as a special exception, the copyright holders give
+# permission to link this program with the OpenSSL library (or with
+# modified versions of OpenSSL that use the same license as OpenSSL),
+# and distribute linked combinations including the two.
+#
+# You must obey the GNU Lesser General Public License in all respects for
+# all of the code used other than OpenSSL.
+#
+# psycopg2 is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+# License for more details.
+
+from psycopg2.extensions import (
+    new_type, new_array_type, register_type, register_adapter, QuotedString)
+
+# The module is imported on register_ipaddress
+ipaddress = None
+
+# The typecasters are created only once
+_casters = None
+
+
+def register_ipaddress(conn_or_curs=None):
+    """
+    Register conversion support between `ipaddress` objects and `network types`__.
+
+    :param conn_or_curs: the scope where to register the type casters.
+        If `!None` register them globally.
+
+    After the function is called, PostgreSQL :sql:`inet` values will be
+    converted into `~ipaddress.IPv4Interface` or `~ipaddress.IPv6Interface`
+    objects, :sql:`cidr` values into into `~ipaddress.IPv4Network` or
+    `~ipaddress.IPv6Network`.
+
+    .. __: https://www.postgresql.org/docs/current/static/datatype-net-types.html
+    """
+    global ipaddress
+    import ipaddress
+
+    global _casters
+    if _casters is None:
+        _casters = _make_casters()
+
+    for c in _casters:
+        register_type(c, conn_or_curs)
+
+    for t in [ipaddress.IPv4Interface, ipaddress.IPv6Interface,
+              ipaddress.IPv4Network, ipaddress.IPv6Network]:
+        register_adapter(t, adapt_ipaddress)
+
+
+def _make_casters():
+    inet = new_type((869,), 'INET', cast_interface)
+    ainet = new_array_type((1041,), 'INET[]', inet)
+
+    cidr = new_type((650,), 'CIDR', cast_network)
+    acidr = new_array_type((651,), 'CIDR[]', cidr)
+
+    return [inet, ainet, cidr, acidr]
+
+
+def cast_interface(s, cur=None):
+    if s is None:
+        return None
+    # Py2 version force the use of unicode. meh.
+    return ipaddress.ip_interface(unicode(s))
+
+
+def cast_network(s, cur=None):
+    if s is None:
+        return None
+    return ipaddress.ip_network(unicode(s))
+
+
+def adapt_ipaddress(obj):
+    return QuotedString(str(obj))

lib/extras.py

@@ -59,6 +59,10 @@ from psycopg2._range import (                               # noqa
     register_range, RangeAdapter, RangeCaster)
 
 
+# Expose ipaddress-related objects
+from psycopg2._ipaddress import register_ipaddress          # noqa
+
+
 class DictCursorBase(_cursor):
     """Base class for all dict-like cursors."""
 

tests/__init__.py

@@ -38,6 +38,7 @@ import test_dates
 import test_errcodes
 import test_extras_dictcursor
 import test_green
+import test_ipaddress
 import test_lobject
 import test_module
 import test_notify
@@ -46,11 +47,7 @@ import test_quote
 import test_transaction
 import test_types_basic
 import test_types_extras
-
-if sys.version_info[:2] >= (2, 5):
 import test_with
-else:
-    test_with = None
 
 
 def test_suite():
@@ -78,6 +75,7 @@ def test_suite():
     suite.addTest(test_errcodes.test_suite())
     suite.addTest(test_extras_dictcursor.test_suite())
     suite.addTest(test_green.test_suite())
+    suite.addTest(test_ipaddress.test_suite())
     suite.addTest(test_lobject.test_suite())
     suite.addTest(test_module.test_suite())
     suite.addTest(test_notify.test_suite())
@@ -86,7 +84,6 @@ def test_suite():
     suite.addTest(test_transaction.test_suite())
     suite.addTest(test_types_basic.test_suite())
     suite.addTest(test_types_extras.test_suite())
-    if test_with:
     suite.addTest(test_with.test_suite())
     return suite
 

tests/test_ipaddress.py

@@ -0,0 +1,131 @@
+#!/usr/bin/env python
+# # test_ipaddress.py - tests for ipaddress support #
+# Copyright (C) 2016 Daniele Varrazzo  <daniele.varrazzo@gmail.com>
+#
+# psycopg2 is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License as published
+# by the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# psycopg2 is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+# License for more details.
+
+from __future__ import unicode_literals
+
+import sys
+from functools import wraps
+
+from testutils import unittest, ConnectingTestCase, decorate_all_tests
+
+import psycopg2
+import psycopg2.extras
+
+
+def skip_if_no_ipaddress(f):
+    @wraps(f)
+    def skip_if_no_ipaddress_(self):
+        if sys.version_info[:2] < (3, 3):
+            try:
+                import ipaddress            # noqa
+            except ImportError:
+                return self.skipTest("'ipaddress' module not available")
+
+        return f(self)
+
+    return skip_if_no_ipaddress_
+
+
+class NetworkingTestCase(ConnectingTestCase):
+    def test_inet_cast(self):
+        import ipaddress as ip
+        cur = self.conn.cursor()
+        psycopg2.extras.register_ipaddress(cur)
+
+        cur.execute("select null::inet")
+        self.assert_(cur.fetchone()[0] is None)
+
+        cur.execute("select '127.0.0.1/24'::inet")
+        obj = cur.fetchone()[0]
+        self.assert_(isinstance(obj, ip.IPv4Interface), repr(obj))
+        self.assertEquals(obj, ip.ip_interface('127.0.0.1/24'))
+
+        cur.execute("select '::ffff:102:300/128'::inet")
+        obj = cur.fetchone()[0]
+        self.assert_(isinstance(obj, ip.IPv6Interface), repr(obj))
+        self.assertEquals(obj, ip.ip_interface('::ffff:102:300/128'))
+
+    def test_inet_array_cast(self):
+        import ipaddress as ip
+        cur = self.conn.cursor()
+        psycopg2.extras.register_ipaddress(cur)
+        cur.execute("select '{NULL,127.0.0.1,::ffff:102:300/128}'::inet[]")
+        l = cur.fetchone()[0]
+        self.assert_(l[0] is None)
+        self.assertEquals(l[1], ip.ip_interface('127.0.0.1'))
+        self.assertEquals(l[2], ip.ip_interface('::ffff:102:300/128'))
+        self.assert_(isinstance(l[1], ip.IPv4Interface), l)
+        self.assert_(isinstance(l[2], ip.IPv6Interface), l)
+
+    def test_inet_adapt(self):
+        import ipaddress as ip
+        cur = self.conn.cursor()
+        psycopg2.extras.register_ipaddress(cur)
+
+        cur.execute("select %s", [ip.ip_interface('127.0.0.1/24')])
+        self.assertEquals(cur.fetchone()[0], '127.0.0.1/24')
+
+        cur.execute("select %s", [ip.ip_interface('::ffff:102:300/128')])
+        self.assertEquals(cur.fetchone()[0], '::ffff:102:300/128')
+
+    def test_cidr_cast(self):
+        import ipaddress as ip
+        cur = self.conn.cursor()
+        psycopg2.extras.register_ipaddress(cur)
+
+        cur.execute("select null::cidr")
+        self.assert_(cur.fetchone()[0] is None)
+
+        cur.execute("select '127.0.0.0/24'::cidr")
+        obj = cur.fetchone()[0]
+        self.assert_(isinstance(obj, ip.IPv4Network), repr(obj))
+        self.assertEquals(obj, ip.ip_network('127.0.0.0/24'))
+
+        cur.execute("select '::ffff:102:300/128'::cidr")
+        obj = cur.fetchone()[0]
+        self.assert_(isinstance(obj, ip.IPv6Network), repr(obj))
+        self.assertEquals(obj, ip.ip_network('::ffff:102:300/128'))
+
+    def test_cidr_array_cast(self):
+        import ipaddress as ip
+        cur = self.conn.cursor()
+        psycopg2.extras.register_ipaddress(cur)
+        cur.execute("select '{NULL,127.0.0.1,::ffff:102:300/128}'::cidr[]")
+        l = cur.fetchone()[0]
+        self.assert_(l[0] is None)
+        self.assertEquals(l[1], ip.ip_network('127.0.0.1'))
+        self.assertEquals(l[2], ip.ip_network('::ffff:102:300/128'))
+        self.assert_(isinstance(l[1], ip.IPv4Network), l)
+        self.assert_(isinstance(l[2], ip.IPv6Network), l)
+
+    def test_cidr_adapt(self):
+        import ipaddress as ip
+        cur = self.conn.cursor()
+        psycopg2.extras.register_ipaddress(cur)
+
+        cur.execute("select %s", [ip.ip_network('127.0.0.0/24')])
+        self.assertEquals(cur.fetchone()[0], '127.0.0.0/24')
+
+        cur.execute("select %s", [ip.ip_network('::ffff:102:300/128')])
+        self.assertEquals(cur.fetchone()[0], '::ffff:102:300/128')
+
+decorate_all_tests(NetworkingTestCase, skip_if_no_ipaddress)
+
+
+def test_suite():
+    return unittest.TestLoader().loadTestsFromName(__name__)
+
+
+if __name__ == "__main__":
+    unittest.main()