262 lines
8.3 KiB
Python
262 lines
8.3 KiB
Python
# engine/url.py
|
|
# Copyright (C) 2005-2017 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
|
|
|
|
"""Provides the :class:`~sqlalchemy.engine.url.URL` class which encapsulates
|
|
information about a database connection specification.
|
|
|
|
The URL object is created automatically when
|
|
:func:`~sqlalchemy.engine.create_engine` is called with a string
|
|
argument; alternatively, the URL is a public-facing construct which can
|
|
be used directly and is also accepted directly by ``create_engine()``.
|
|
"""
|
|
|
|
import re
|
|
from .. import exc, util
|
|
from . import Dialect
|
|
from ..dialects import registry, plugins
|
|
|
|
|
|
class URL(object):
|
|
"""
|
|
Represent the components of a URL used to connect to a database.
|
|
|
|
This object is suitable to be passed directly to a
|
|
:func:`~sqlalchemy.create_engine` call. The fields of the URL are parsed
|
|
from a string by the :func:`.make_url` function. the string
|
|
format of the URL is an RFC-1738-style string.
|
|
|
|
All initialization parameters are available as public attributes.
|
|
|
|
:param drivername: the name of the database backend.
|
|
This name will correspond to a module in sqlalchemy/databases
|
|
or a third party plug-in.
|
|
|
|
:param username: The user name.
|
|
|
|
:param password: database password.
|
|
|
|
:param host: The name of the host.
|
|
|
|
:param port: The port number.
|
|
|
|
:param database: The database name.
|
|
|
|
:param query: A dictionary of options to be passed to the
|
|
dialect and/or the DBAPI upon connect.
|
|
|
|
"""
|
|
|
|
def __init__(self, drivername, username=None, password=None,
|
|
host=None, port=None, database=None, query=None):
|
|
self.drivername = drivername
|
|
self.username = username
|
|
self.password = password
|
|
self.host = host
|
|
if port is not None:
|
|
self.port = int(port)
|
|
else:
|
|
self.port = None
|
|
self.database = database
|
|
self.query = query or {}
|
|
|
|
def __to_string__(self, hide_password=True):
|
|
s = self.drivername + "://"
|
|
if self.username is not None:
|
|
s += _rfc_1738_quote(self.username)
|
|
if self.password is not None:
|
|
s += ':' + ('***' if hide_password
|
|
else _rfc_1738_quote(self.password))
|
|
s += "@"
|
|
if self.host is not None:
|
|
if ':' in self.host:
|
|
s += "[%s]" % self.host
|
|
else:
|
|
s += self.host
|
|
if self.port is not None:
|
|
s += ':' + str(self.port)
|
|
if self.database is not None:
|
|
s += '/' + self.database
|
|
if self.query:
|
|
keys = list(self.query)
|
|
keys.sort()
|
|
s += '?' + "&".join("%s=%s" % (k, self.query[k]) for k in keys)
|
|
return s
|
|
|
|
def __str__(self):
|
|
return self.__to_string__(hide_password=False)
|
|
|
|
def __repr__(self):
|
|
return self.__to_string__()
|
|
|
|
def __hash__(self):
|
|
return hash(str(self))
|
|
|
|
def __eq__(self, other):
|
|
return \
|
|
isinstance(other, URL) and \
|
|
self.drivername == other.drivername and \
|
|
self.username == other.username and \
|
|
self.password == other.password and \
|
|
self.host == other.host and \
|
|
self.database == other.database and \
|
|
self.query == other.query
|
|
|
|
def get_backend_name(self):
|
|
if '+' not in self.drivername:
|
|
return self.drivername
|
|
else:
|
|
return self.drivername.split('+')[0]
|
|
|
|
def get_driver_name(self):
|
|
if '+' not in self.drivername:
|
|
return self.get_dialect().driver
|
|
else:
|
|
return self.drivername.split('+')[1]
|
|
|
|
def _instantiate_plugins(self, kwargs):
|
|
plugin_names = util.to_list(self.query.get('plugin', ()))
|
|
|
|
return [
|
|
plugins.load(plugin_name)(self, kwargs)
|
|
for plugin_name in plugin_names
|
|
]
|
|
|
|
def _get_entrypoint(self):
|
|
"""Return the "entry point" dialect class.
|
|
|
|
This is normally the dialect itself except in the case when the
|
|
returned class implements the get_dialect_cls() method.
|
|
|
|
"""
|
|
if '+' not in self.drivername:
|
|
name = self.drivername
|
|
else:
|
|
name = self.drivername.replace('+', '.')
|
|
cls = registry.load(name)
|
|
# check for legacy dialects that
|
|
# would return a module with 'dialect' as the
|
|
# actual class
|
|
if hasattr(cls, 'dialect') and \
|
|
isinstance(cls.dialect, type) and \
|
|
issubclass(cls.dialect, Dialect):
|
|
return cls.dialect
|
|
else:
|
|
return cls
|
|
|
|
def get_dialect(self):
|
|
"""Return the SQLAlchemy database dialect class corresponding
|
|
to this URL's driver name.
|
|
"""
|
|
entrypoint = self._get_entrypoint()
|
|
dialect_cls = entrypoint.get_dialect_cls(self)
|
|
return dialect_cls
|
|
|
|
def translate_connect_args(self, names=[], **kw):
|
|
r"""Translate url attributes into a dictionary of connection arguments.
|
|
|
|
Returns attributes of this url (`host`, `database`, `username`,
|
|
`password`, `port`) as a plain dictionary. The attribute names are
|
|
used as the keys by default. Unset or false attributes are omitted
|
|
from the final dictionary.
|
|
|
|
:param \**kw: Optional, alternate key names for url attributes.
|
|
|
|
:param names: Deprecated. Same purpose as the keyword-based alternate
|
|
names, but correlates the name to the original positionally.
|
|
"""
|
|
|
|
translated = {}
|
|
attribute_names = ['host', 'database', 'username', 'password', 'port']
|
|
for sname in attribute_names:
|
|
if names:
|
|
name = names.pop(0)
|
|
elif sname in kw:
|
|
name = kw[sname]
|
|
else:
|
|
name = sname
|
|
if name is not None and getattr(self, sname, False):
|
|
translated[name] = getattr(self, sname)
|
|
return translated
|
|
|
|
|
|
def make_url(name_or_url):
|
|
"""Given a string or unicode instance, produce a new URL instance.
|
|
|
|
The given string is parsed according to the RFC 1738 spec. If an
|
|
existing URL object is passed, just returns the object.
|
|
"""
|
|
|
|
if isinstance(name_or_url, util.string_types):
|
|
return _parse_rfc1738_args(name_or_url)
|
|
else:
|
|
return name_or_url
|
|
|
|
|
|
def _parse_rfc1738_args(name):
|
|
pattern = re.compile(r'''
|
|
(?P<name>[\w\+]+)://
|
|
(?:
|
|
(?P<username>[^:/]*)
|
|
(?::(?P<password>.*))?
|
|
@)?
|
|
(?:
|
|
(?:
|
|
\[(?P<ipv6host>[^/]+)\] |
|
|
(?P<ipv4host>[^/:]+)
|
|
)?
|
|
(?::(?P<port>[^/]*))?
|
|
)?
|
|
(?:/(?P<database>.*))?
|
|
''', re.X)
|
|
|
|
m = pattern.match(name)
|
|
if m is not None:
|
|
components = m.groupdict()
|
|
if components['database'] is not None:
|
|
tokens = components['database'].split('?', 2)
|
|
components['database'] = tokens[0]
|
|
query = (
|
|
len(tokens) > 1 and dict(util.parse_qsl(tokens[1]))) or None
|
|
if util.py2k and query is not None:
|
|
query = dict((k.encode('ascii'), query[k]) for k in query)
|
|
else:
|
|
query = None
|
|
components['query'] = query
|
|
|
|
if components['username'] is not None:
|
|
components['username'] = _rfc_1738_unquote(components['username'])
|
|
|
|
if components['password'] is not None:
|
|
components['password'] = _rfc_1738_unquote(components['password'])
|
|
|
|
ipv4host = components.pop('ipv4host')
|
|
ipv6host = components.pop('ipv6host')
|
|
components['host'] = ipv4host or ipv6host
|
|
name = components.pop('name')
|
|
return URL(name, **components)
|
|
else:
|
|
raise exc.ArgumentError(
|
|
"Could not parse rfc1738 URL from string '%s'" % name)
|
|
|
|
|
|
def _rfc_1738_quote(text):
|
|
return re.sub(r'[:@/]', lambda m: "%%%X" % ord(m.group(0)), text)
|
|
|
|
|
|
def _rfc_1738_unquote(text):
|
|
return util.unquote(text)
|
|
|
|
|
|
def _parse_keyvalue_args(name):
|
|
m = re.match(r'(\w+)://(.*)', name)
|
|
if m is not None:
|
|
(name, args) = m.group(1, 2)
|
|
opts = dict(util.parse_qsl(args))
|
|
return URL(name, *opts)
|
|
else:
|
|
return None
|