gaerdbms.py 3.4 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102
  1. # mysql/gaerdbms.py
  2. # Copyright (C) 2005-2017 the SQLAlchemy authors and contributors
  3. # <see AUTHORS file>
  4. #
  5. # This module is part of SQLAlchemy and is released under
  6. # the MIT License: http://www.opensource.org/licenses/mit-license.php
  7. """
  8. .. dialect:: mysql+gaerdbms
  9. :name: Google Cloud SQL
  10. :dbapi: rdbms
  11. :connectstring: mysql+gaerdbms:///<dbname>?instance=<instancename>
  12. :url: https://developers.google.com/appengine/docs/python/cloud-sql/\
  13. developers-guide
  14. This dialect is based primarily on the :mod:`.mysql.mysqldb` dialect with
  15. minimal changes.
  16. .. versionadded:: 0.7.8
  17. .. deprecated:: 1.0 This dialect is **no longer necessary** for
  18. Google Cloud SQL; the MySQLdb dialect can be used directly.
  19. Cloud SQL now recommends creating connections via the
  20. mysql dialect using the URL format
  21. ``mysql+mysqldb://root@/<dbname>?unix_socket=/cloudsql/<projectid>:<instancename>``
  22. Pooling
  23. -------
  24. Google App Engine connections appear to be randomly recycled,
  25. so the dialect does not pool connections. The :class:`.NullPool`
  26. implementation is installed within the :class:`.Engine` by
  27. default.
  28. """
  29. import os
  30. from .mysqldb import MySQLDialect_mysqldb
  31. from ...pool import NullPool
  32. import re
  33. from sqlalchemy.util import warn_deprecated
  34. def _is_dev_environment():
  35. return os.environ.get('SERVER_SOFTWARE', '').startswith('Development/')
  36. class MySQLDialect_gaerdbms(MySQLDialect_mysqldb):
  37. @classmethod
  38. def dbapi(cls):
  39. warn_deprecated(
  40. "Google Cloud SQL now recommends creating connections via the "
  41. "MySQLdb dialect directly, using the URL format "
  42. "mysql+mysqldb://root@/<dbname>?unix_socket=/cloudsql/"
  43. "<projectid>:<instancename>"
  44. )
  45. # from django:
  46. # http://code.google.com/p/googleappengine/source/
  47. # browse/trunk/python/google/storage/speckle/
  48. # python/django/backend/base.py#118
  49. # see also [ticket:2649]
  50. # see also http://stackoverflow.com/q/14224679/34549
  51. from google.appengine.api import apiproxy_stub_map
  52. if _is_dev_environment():
  53. from google.appengine.api import rdbms_mysqldb
  54. return rdbms_mysqldb
  55. elif apiproxy_stub_map.apiproxy.GetStub('rdbms'):
  56. from google.storage.speckle.python.api import rdbms_apiproxy
  57. return rdbms_apiproxy
  58. else:
  59. from google.storage.speckle.python.api import rdbms_googleapi
  60. return rdbms_googleapi
  61. @classmethod
  62. def get_pool_class(cls, url):
  63. # Cloud SQL connections die at any moment
  64. return NullPool
  65. def create_connect_args(self, url):
  66. opts = url.translate_connect_args()
  67. if not _is_dev_environment():
  68. # 'dsn' and 'instance' are because we are skipping
  69. # the traditional google.api.rdbms wrapper
  70. opts['dsn'] = ''
  71. opts['instance'] = url.query['instance']
  72. return [], opts
  73. def _extract_error_code(self, exception):
  74. match = re.compile(r"^(\d+)L?:|^\((\d+)L?,").match(str(exception))
  75. # The rdbms api will wrap then re-raise some types of errors
  76. # making this regex return no matches.
  77. code = match.group(1) or match.group(2) if match else None
  78. if code:
  79. return int(code)
  80. dialect = MySQLDialect_gaerdbms