diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/_json.py | 57 |
1 files changed, 5 insertions, 52 deletions
diff --git a/lib/_json.py b/lib/_json.py index f90bac5..7757b6e 100644 --- a/lib/_json.py +++ b/lib/_json.py @@ -52,43 +52,11 @@ class Json(object): An `~psycopg2.extensions.ISQLQuote` wrapper to adapt a Python object to :sql:`json` data type. - `!Json` can be used to wrap any object supported by the underlying - `!json` module. `~psycopg2.extensions.ISQLQuote.getquoted()` will raise - `!ImportError` if no module is available. - - The basic usage is to wrap `!Json` around the object to be adapted:: - - curs.execute("insert into mytable (jsondata) values (%s)", - [Json({'a': 100})]) - - If you want to customize the adaptation from Python to PostgreSQL you can - either provide a custom *dumps* function:: - - curs.execute("insert into mytable (jsondata) values (%s)", - [Json({'a': 100}, dumps=simplejson.dumps)]) - - or you can subclass `!Json` overriding the `dumps()` method:: - - class MyJson(Json): - def dumps(self, obj): - return simplejson.dumps(obj) - - curs.execute("insert into mytable (jsondata) values (%s)", - [MyJson({'a': 100})]) - - .. note:: - - You can use `~psycopg2.extensions.register_adapter()` to adapt any - Python dictionary to JSON, either using `!Json` or any subclass or - factory creating a compatible adapter:: - - psycopg2.extensions.register_adapter(dict, psycopg2.extras.Json) - - This setting is global though, so it is not compatible with similar - adapters such as the one registered by `register_hstore()`. Any other - object supported by JSON can be registered the same way, but this will - clobber the default adaptation rule, so be careful to unwanted side - effects. + `!Json` can be used to wrap any object supported by the provided *dumps* + function. If none is provided, the standard :py:func:`json.dumps()` is + used (`!simplejson` for Python < 2.6; + `~psycopg2.extensions.ISQLQuote.getquoted()` will raise `!ImportError` if + the module is available). """ def __init__(self, adapted, dumps=None): @@ -143,20 +111,6 @@ def register_json(conn_or_curs=None, globally=False, loads=None, :param array_oid: the OID of the :sql:`json[]` array type if known; if not, it will be queried on *conn_or_curs* - Using the function is required to convert :sql:`json` data in PostgreSQL - versions before 9.2. Since 9.2 the oids are hardcoded so a default - typecaster is already registered. The :sql:`json` type is available as - `extension for PostgreSQL 9.1`__. - - .. __: http://people.planetpostgresql.org/andrew/index.php?/archives/255-JSON-for-PG-9.2-...-and-now-for-9.1!.html - - Another use of the function is to adapt :sql:`json` using a customized - load function. For example, if you want to convert the float values in the - :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) - 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 @@ -187,7 +141,6 @@ 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): """Create typecasters for json data type.""" if loads is None: |