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# postgresql/pygresql.py
# Copyright (C) 2005-2021 the SQLAlchemy authors and contributors
# <see AUTHORS file>
#
# This module is part of SQLAlchemy and is released under
# the MIT License: http://www.opensource.org/licenses/mit-license.php
"""
.. dialect:: postgresql+pygresql
:name: pygresql
:dbapi: pgdb
:connectstring: postgresql+pygresql://user:password@host:port/dbname[?key=value&key=value...]
:url: http://www.pygresql.org/
.. note::
The pygresql dialect is **not tested as part of SQLAlchemy's continuous
integration** and may have unresolved issues. The recommended PostgreSQL
dialect is psycopg2.
""" # noqa
import decimal
import re
from .base import _DECIMAL_TYPES
from .base import _FLOAT_TYPES
from .base import _INT_TYPES
from .base import PGCompiler
from .base import PGDialect
from .base import PGIdentifierPreparer
from .base import UUID
from .hstore import HSTORE
from .json import JSON
from .json import JSONB
from ... import exc
from ... import processors
from ... import util
from ...sql.elements import Null
from ...types import JSON as Json
from ...types import Numeric
class _PGNumeric(Numeric):
def bind_processor(self, dialect):
return None
def result_processor(self, dialect, coltype):
if not isinstance(coltype, int):
coltype = coltype.oid
if self.asdecimal:
if coltype in _FLOAT_TYPES:
return processors.to_decimal_processor_factory(
decimal.Decimal, self._effective_decimal_return_scale
)
elif coltype in _DECIMAL_TYPES or coltype in _INT_TYPES:
# PyGreSQL returns Decimal natively for 1700 (numeric)
return None
else:
raise exc.InvalidRequestError(
"Unknown PG numeric type: %d" % coltype
)
else:
if coltype in _FLOAT_TYPES:
# PyGreSQL returns float natively for 701 (float8)
return None
elif coltype in _DECIMAL_TYPES or coltype in _INT_TYPES:
return processors.to_float
else:
raise exc.InvalidRequestError(
"Unknown PG numeric type: %d" % coltype
)
class _PGHStore(HSTORE):
def bind_processor(self, dialect):
if not dialect.has_native_hstore:
return super(_PGHStore, self).bind_processor(dialect)
hstore = dialect.dbapi.Hstore
def process(value):
if isinstance(value, dict):
return hstore(value)
return value
return process
def result_processor(self, dialect, coltype):
if not dialect.has_native_hstore:
return super(_PGHStore, self).result_processor(dialect, coltype)
class _PGJSON(JSON):
def bind_processor(self, dialect):
if not dialect.has_native_json:
return super(_PGJSON, self).bind_processor(dialect)
json = dialect.dbapi.Json
def process(value):
if value is self.NULL:
value = None
elif isinstance(value, Null) or (
value is None and self.none_as_null
):
return None
if value is None or isinstance(value, (dict, list)):
return json(value)
return value
return process
def result_processor(self, dialect, coltype):
if not dialect.has_native_json:
return super(_PGJSON, self).result_processor(dialect, coltype)
class _PGJSONB(JSONB):
def bind_processor(self, dialect):
if not dialect.has_native_json:
return super(_PGJSONB, self).bind_processor(dialect)
json = dialect.dbapi.Json
def process(value):
if value is self.NULL:
value = None
elif isinstance(value, Null) or (
value is None and self.none_as_null
):
return None
if value is None or isinstance(value, (dict, list)):
return json(value)
return value
return process
def result_processor(self, dialect, coltype):
if not dialect.has_native_json:
return super(_PGJSONB, self).result_processor(dialect, coltype)
class _PGUUID(UUID):
def bind_processor(self, dialect):
if not dialect.has_native_uuid:
return super(_PGUUID, self).bind_processor(dialect)
uuid = dialect.dbapi.Uuid
def process(value):
if value is None:
return None
if isinstance(value, (str, bytes)):
if len(value) == 16:
return uuid(bytes=value)
return uuid(value)
if isinstance(value, int):
return uuid(int=value)
return value
return process
def result_processor(self, dialect, coltype):
if not dialect.has_native_uuid:
return super(_PGUUID, self).result_processor(dialect, coltype)
if not self.as_uuid:
def process(value):
if value is not None:
return str(value)
return process
class _PGCompiler(PGCompiler):
def visit_mod_binary(self, binary, operator, **kw):
return (
self.process(binary.left, **kw)
+ " %% "
+ self.process(binary.right, **kw)
)
def post_process_text(self, text):
return text.replace("%", "%%")
class _PGIdentifierPreparer(PGIdentifierPreparer):
def _escape_identifier(self, value):
value = value.replace(self.escape_quote, self.escape_to_quote)
return value.replace("%", "%%")
class PGDialect_pygresql(PGDialect):
driver = "pygresql"
statement_compiler = _PGCompiler
preparer = _PGIdentifierPreparer
@classmethod
def dbapi(cls):
import pgdb
return pgdb
colspecs = util.update_copy(
PGDialect.colspecs,
{
Numeric: _PGNumeric,
HSTORE: _PGHStore,
Json: _PGJSON,
JSON: _PGJSON,
JSONB: _PGJSONB,
UUID: _PGUUID,
},
)
def __init__(self, **kwargs):
super(PGDialect_pygresql, self).__init__(**kwargs)
try:
version = self.dbapi.version
m = re.match(r"(\d+)\.(\d+)", version)
version = (int(m.group(1)), int(m.group(2)))
except (AttributeError, ValueError, TypeError):
version = (0, 0)
self.dbapi_version = version
if version < (5, 0):
has_native_hstore = has_native_json = has_native_uuid = False
if version != (0, 0):
util.warn(
"PyGreSQL is only fully supported by SQLAlchemy"
" since version 5.0."
)
else:
self.supports_unicode_statements = True
self.supports_unicode_binds = True
has_native_hstore = has_native_json = has_native_uuid = True
self.has_native_hstore = has_native_hstore
self.has_native_json = has_native_json
self.has_native_uuid = has_native_uuid
def create_connect_args(self, url):
opts = url.translate_connect_args(username="user")
if "port" in opts:
opts["host"] = "%s:%s" % (
opts.get("host", "").rsplit(":", 1)[0],
opts.pop("port"),
)
opts.update(url.query)
return [], opts
def is_disconnect(self, e, connection, cursor):
if isinstance(e, self.dbapi.Error):
if not connection:
return False
try:
connection = connection.connection
except AttributeError:
pass
else:
if not connection:
return False
try:
return connection.closed
except AttributeError: # PyGreSQL < 5.0
return connection._cnx is None
return False
dialect = PGDialect_pygresql
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