Merge branch 'jsonb'

This commit is contained in:
Daniele Varrazzo 2014-08-13 02:03:11 +01:00
commit 0b95194f74
7 changed files with 171 additions and 31 deletions

1
NEWS
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@ -13,6 +13,7 @@ Bug fixes:
What's new in psycopg 2.5.4
^^^^^^^^^^^^^^^^^^^^^^^^^^^
- Added :sql:`jsonb` support for PostgreSQL 9.4.
- Fixed segfault if COPY statements are executed instead of using the
proper methods (:ticket:`#219`).
- Don't ignore silently the `cursor.callproc` argument without a length.

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@ -160,23 +160,27 @@ JSON_ adaptation
^^^^^^^^^^^^^^^^
.. versionadded:: 2.5
.. versionchanged:: 2.5.4
added |jsonb| support. In previous versions |jsonb| values are returned
as strings. See :ref:`the FAQ <faq-jsonb-adapt>` for a workaround.
Psycopg can adapt Python objects to and from the PostgreSQL |pgjson|_ type.
With PostgreSQL 9.2 adaptation is available out-of-the-box. To use JSON data
with previous database versions (either with the `9.1 json extension`__, but
even if you want to convert text fields to JSON) you can use
`register_json()`.
Psycopg can adapt Python objects to and from the PostgreSQL |pgjson|_ and
|jsonb| types. With PostgreSQL 9.2 and following versions adaptation is
available out-of-the-box. To use JSON data with previous database versions
(either with the `9.1 json extension`__, but even if you want to convert text
fields to JSON) you can use the `register_json()` function.
.. __: http://people.planetpostgresql.org/andrew/index.php?/archives/255-JSON-for-PG-9.2-...-and-now-for-9.1!.html
The Python library used to convert Python objects to JSON depends on the
language version: with Python 2.6 and following the :py:mod:`json` module from
the standard library is used; with previous versions the `simplejson`_ module
is used if available. Note that the last `!simplejson` version supporting
Python 2.4 is the 2.0.9.
The Python library used by default to convert Python objects to JSON and to
parse data from the database depends on the language version: with Python 2.6
and following the :py:mod:`json` module from the standard library is used;
with previous versions the `simplejson`_ module is used if available. Note
that the last `!simplejson` version supporting Python 2.4 is the 2.0.9.
.. _JSON: http://www.json.org/
.. |pgjson| replace:: :sql:`json`
.. |jsonb| replace:: :sql:`jsonb`
.. _pgjson: http://www.postgresql.org/docs/current/static/datatype-json.html
.. _simplejson: http://pypi.python.org/pypi/simplejson/
@ -186,8 +190,8 @@ the `Json` adapter::
curs.execute("insert into mytable (jsondata) values (%s)",
[Json({'a': 100})])
Reading from the database, |pgjson| values will be automatically converted to
Python objects.
Reading from the database, |pgjson| and |jsonb| values will be automatically
converted to Python objects.
.. note::
@ -233,9 +237,11 @@ or you can subclass it overriding the `~Json.dumps()` method::
[MyJson({'a': 100})])
Customizing the conversion from PostgreSQL to Python can be done passing a
custom `!loads()` function to `register_json()` (or `register_default_json()`
for PostgreSQL 9.2). For example, if you want to convert the float values
from :sql:`json` into :py:class:`~decimal.Decimal` you can use::
custom `!loads()` function to `register_json()`. For the builtin data types
(|pgjson| from PostgreSQL 9.2, |jsonb| from PostgreSQL 9.4) use
`register_default_json()` and `register_default_jsonb()`. For example, if you
want to convert the float values from :sql:`json` into
:py:class:`~decimal.Decimal` you can use::
loads = lambda x: json.loads(x, parse_float=Decimal)
psycopg2.extras.register_json(conn, loads=loads)
@ -248,8 +254,15 @@ from :sql:`json` into :py:class:`~decimal.Decimal` you can use::
.. autofunction:: register_json
.. versionchanged:: 2.5.4
added the *name* parameter to enable :sql:`jsonb` support.
.. autofunction:: register_default_json
.. autofunction:: register_default_jsonb
.. versionadded:: 2.5.4
.. index::

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@ -137,6 +137,20 @@ Psycopg automatically converts PostgreSQL :sql:`json` data into Python objects.
See :ref:`adapt-json` for further details.
.. _faq-jsonb-adapt:
.. cssclass:: faq
Psycopg converts :sql:`json` values into Python objects but :sql:`jsonb` values are returned as strings. Can :sql:`jsonb` be converted automatically?
Automatic conversion of :sql:`jsonb` values is supported from Psycopg
release 2.5.4. For previous versions you can register the :sql:`json`
typecaster on the :sql:`jsonb` oids (which are known and not suppsed to
change in future PostgreSQL versions)::
psycopg2.extras.register_json(oid=3802, array_oid=3807, globally=True)
See :ref:`adapt-json` for further details.
.. _faq-bytea-9.0:
.. cssclass:: faq

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@ -47,6 +47,10 @@ else:
JSON_OID = 114
JSONARRAY_OID = 199
# oids from PostgreSQL 9.4
JSONB_OID = 3802
JSONBARRAY_OID = 3807
class Json(object):
"""
An `~psycopg2.extensions.ISQLQuote` wrapper to adapt a Python object to
@ -102,7 +106,7 @@ class Json(object):
def register_json(conn_or_curs=None, globally=False, loads=None,
oid=None, array_oid=None):
oid=None, array_oid=None, name='json'):
"""Create and register typecasters converting :sql:`json` type to Python objects.
:param conn_or_curs: a connection or cursor used to find the :sql:`json`
@ -118,17 +122,19 @@ def register_json(conn_or_curs=None, globally=False, loads=None,
queried on *conn_or_curs*
:param array_oid: the OID of the :sql:`json[]` array type if known;
if not, it will be queried on *conn_or_curs*
:param name: the name of the data type to look for in *conn_or_curs*
The connection or cursor passed to the function will be used to query the
database and look for the OID of the :sql:`json` type. No query is
performed if *oid* and *array_oid* are provided. Raise
`~psycopg2.ProgrammingError` if the type is not found.
database and look for the OID of the :sql:`json` type (or an alternative
type if *name* if provided). No query is performed if *oid* and *array_oid*
are provided. Raise `~psycopg2.ProgrammingError` if the type is not found.
"""
if oid is None:
oid, array_oid = _get_json_oids(conn_or_curs)
oid, array_oid = _get_json_oids(conn_or_curs, name)
JSON, JSONARRAY = _create_json_typecasters(oid, array_oid, loads)
JSON, JSONARRAY = _create_json_typecasters(
oid, array_oid, loads=loads, name=name.upper())
register_type(JSON, not globally and conn_or_curs or None)
@ -149,7 +155,19 @@ def register_default_json(conn_or_curs=None, globally=False, loads=None):
return register_json(conn_or_curs=conn_or_curs, globally=globally,
loads=loads, oid=JSON_OID, array_oid=JSONARRAY_OID)
def _create_json_typecasters(oid, array_oid, loads=None):
def register_default_jsonb(conn_or_curs=None, globally=False, loads=None):
"""
Create and register :sql:`jsonb` typecasters for PostgreSQL 9.4 and following.
As in `register_default_json()`, the function allows to register a
customized *loads* function for the :sql:`jsonb` type at its known oid for
PostgreSQL 9.4 and following versions. All the parameters have the same
meaning of `register_json()`.
"""
return register_json(conn_or_curs=conn_or_curs, globally=globally,
loads=loads, oid=JSONB_OID, array_oid=JSONBARRAY_OID, name='jsonb')
def _create_json_typecasters(oid, array_oid, loads=None, name='JSON'):
"""Create typecasters for json data type."""
if loads is None:
if json is None:
@ -162,15 +180,15 @@ def _create_json_typecasters(oid, array_oid, loads=None):
return None
return loads(s)
JSON = new_type((oid, ), 'JSON', typecast_json)
JSON = new_type((oid, ), name, typecast_json)
if array_oid is not None:
JSONARRAY = new_array_type((array_oid, ), "JSONARRAY", JSON)
JSONARRAY = new_array_type((array_oid, ), "%sARRAY" % name, JSON)
else:
JSONARRAY = None
return JSON, JSONARRAY
def _get_json_oids(conn_or_curs):
def _get_json_oids(conn_or_curs, name='json'):
# lazy imports
from psycopg2.extensions import STATUS_IN_TRANSACTION
from psycopg2.extras import _solve_conn_curs
@ -185,8 +203,8 @@ def _get_json_oids(conn_or_curs):
# get the oid for the hstore
curs.execute(
"SELECT t.oid, %s FROM pg_type t WHERE t.typname = 'json';"
% typarray)
"SELECT t.oid, %s FROM pg_type t WHERE t.typname = %%s;"
% typarray, (name,))
r = curs.fetchone()
# revert the status of the connection as before the command
@ -194,7 +212,7 @@ def _get_json_oids(conn_or_curs):
conn.rollback()
if not r:
raise conn.ProgrammingError("json data type not found")
raise conn.ProgrammingError("%s data type not found" % name)
return r

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@ -152,20 +152,22 @@ class NoneAdapter(object):
# Create default json typecasters for PostgreSQL 9.2 oids
from psycopg2._json import register_default_json
from psycopg2._json import register_default_json, register_default_jsonb
try:
JSON, JSONARRAY = register_default_json()
JSONB, JSONBARRAY = register_default_jsonb()
except ImportError:
pass
del register_default_json
del register_default_json, register_default_jsonb
# Create default Range typecasters
from psycopg2. _range import Range
del Range
# Add the "cleaned" version of the encodings to the key.
# When the encoding is set its name is cleaned up from - and _ and turned
# uppercase, so an encoding not respecting these rules wouldn't be found in the

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@ -965,7 +965,8 @@ def register_composite(name, conn_or_curs, globally=False, factory=None):
# expose the json adaptation stuff into the module
from psycopg2._json import json, Json, register_json, register_default_json
from psycopg2._json import json, Json, register_json
from psycopg2._json import register_default_json, register_default_jsonb
# Expose range-related objects

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@ -1069,6 +1069,97 @@ class JsonTestCase(ConnectingTestCase):
self.assert_(s.endswith("'"))
def skip_if_no_jsonb_type(f):
return skip_before_postgres(9, 4)(f)
class JsonbTestCase(ConnectingTestCase):
@staticmethod
def myloads(s):
import json
rv = json.loads(s)
rv['test'] = 1
return rv
def test_default_cast(self):
curs = self.conn.cursor()
curs.execute("""select '{"a": 100.0, "b": null}'::jsonb""")
self.assertEqual(curs.fetchone()[0], {'a': 100.0, 'b': None})
curs.execute("""select array['{"a": 100.0, "b": null}']::jsonb[]""")
self.assertEqual(curs.fetchone()[0], [{'a': 100.0, 'b': None}])
def test_register_on_connection(self):
psycopg2.extras.register_json(self.conn, loads=self.myloads, name='jsonb')
curs = self.conn.cursor()
curs.execute("""select '{"a": 100.0, "b": null}'::jsonb""")
self.assertEqual(curs.fetchone()[0], {'a': 100.0, 'b': None, 'test': 1})
def test_register_on_cursor(self):
curs = self.conn.cursor()
psycopg2.extras.register_json(curs, loads=self.myloads, name='jsonb')
curs.execute("""select '{"a": 100.0, "b": null}'::jsonb""")
self.assertEqual(curs.fetchone()[0], {'a': 100.0, 'b': None, 'test': 1})
def test_register_globally(self):
old = psycopg2.extensions.string_types.get(3802)
olda = psycopg2.extensions.string_types.get(3807)
try:
new, newa = psycopg2.extras.register_json(self.conn,
loads=self.myloads, globally=True, name='jsonb')
curs = self.conn.cursor()
curs.execute("""select '{"a": 100.0, "b": null}'::jsonb""")
self.assertEqual(curs.fetchone()[0], {'a': 100.0, 'b': None, 'test': 1})
finally:
psycopg2.extensions.string_types.pop(new.values[0])
psycopg2.extensions.string_types.pop(newa.values[0])
if old:
psycopg2.extensions.register_type(old)
if olda:
psycopg2.extensions.register_type(olda)
def test_loads(self):
json = psycopg2.extras.json
loads = lambda x: json.loads(x, parse_float=Decimal)
psycopg2.extras.register_json(self.conn, loads=loads, name='jsonb')
curs = self.conn.cursor()
curs.execute("""select '{"a": 100.0, "b": null}'::jsonb""")
data = curs.fetchone()[0]
self.assert_(isinstance(data['a'], Decimal))
self.assertEqual(data['a'], Decimal('100.0'))
# sure we are not manling json too?
curs.execute("""select '{"a": 100.0, "b": null}'::json""")
data = curs.fetchone()[0]
self.assert_(isinstance(data['a'], float))
self.assertEqual(data['a'], 100.0)
def test_register_default(self):
curs = self.conn.cursor()
loads = lambda x: psycopg2.extras.json.loads(x, parse_float=Decimal)
psycopg2.extras.register_default_jsonb(curs, loads=loads)
curs.execute("""select '{"a": 100.0, "b": null}'::jsonb""")
data = curs.fetchone()[0]
self.assert_(isinstance(data['a'], Decimal))
self.assertEqual(data['a'], Decimal('100.0'))
curs.execute("""select array['{"a": 100.0, "b": null}']::jsonb[]""")
data = curs.fetchone()[0]
self.assert_(isinstance(data[0]['a'], Decimal))
self.assertEqual(data[0]['a'], Decimal('100.0'))
def test_null(self):
curs = self.conn.cursor()
curs.execute("""select NULL::jsonb""")
self.assertEqual(curs.fetchone()[0], None)
curs.execute("""select NULL::jsonb[]""")
self.assertEqual(curs.fetchone()[0], None)
decorate_all_tests(JsonbTestCase, skip_if_no_json_module)
decorate_all_tests(JsonbTestCase, skip_if_no_jsonb_type)
class RangeTestCase(unittest.TestCase):
def test_noparam(self):
from psycopg2.extras import Range