Обработка ошибок Flask

1

Я пытаюсь поймать ошибку, сгенерированную flask- sqlalchemy. Мой код, к сожалению, не может справиться с этой ошибкой, потому что отладчик ловит его первым. Это происходит, когда я пытаюсь вставить запись в базу данных с полем, который должен быть уникальным, но дублируется. Есть ли способ обойти это? Это трассировка.

sqlalchemy.exc.IntegrityError

IntegrityError: (IntegrityError) column username is not unique u'INSERT INTO user (username, password, karma) VALUES (?, ?, ?)' (u'Test', u'test', 0)
Traceback (most recent call last)

    *
      File "/home/josh/Projects/masterpieces_of_code/env/lib/python2.6/site-packages/flask/app.py", line 889, in __call__

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] return self.wsgi_app(environ, start_response)

    *
      File "/home/josh/Projects/masterpieces_of_code/env/lib/python2.6/site-packages/flask/app.py", line 879, in wsgi_app

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] response = self.make_response(self.handle_exception(e))

    *
      File "/home/josh/Projects/masterpieces_of_code/env/lib/python2.6/site-packages/flask/app.py", line 876, in wsgi_app

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] rv = self.dispatch_request()

    *
      File "/home/josh/Projects/masterpieces_of_code/env/lib/python2.6/site-packages/flask/app.py", line 695, in dispatch_request

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] return self.view_functions[rule.endpoint](**req.view_args)

    *
      File "/home/josh/Projects/masterpieces_of_code/app.py", line 70, in create_user

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] db.session.commit()

    *
      File "/usr/share/pyshared/sqlalchemy/orm/scoping.py", line 129, in do

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] return getattr(self.registry(), name)(*args, **kwargs)

    *
      File "/usr/share/pyshared/sqlalchemy/orm/session.py", line 653, in commit

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] self.transaction.commit()

    *
      File "/usr/share/pyshared/sqlalchemy/orm/session.py", line 364, in commit

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] self._prepare_impl()

    *
      File "/usr/share/pyshared/sqlalchemy/orm/session.py", line 348, in _prepare_impl

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] self.session.flush()

    *
      File "/usr/share/pyshared/sqlalchemy/orm/session.py", line 1346, in flush

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] self._flush(objects)

    *
      File "/usr/share/pyshared/sqlalchemy/orm/session.py", line 1427, in _flush

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] flush_context.execute()

    *
      File "/usr/share/pyshared/sqlalchemy/orm/unitofwork.py", line 299, in execute

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] rec.execute(self)

    *
      File "/usr/share/pyshared/sqlalchemy/orm/unitofwork.py", line 443, in execute

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] uow

    *
      File "/usr/share/pyshared/sqlalchemy/orm/mapper.py", line 1833, in _save_obj

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] execute(statement, params)

    *
      File "/usr/share/pyshared/sqlalchemy/engine/base.py", line 1794, in execute

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] object, *multiparams, **params)

    *
      File "/usr/share/pyshared/sqlalchemy/interfaces.py", line 149, in execute

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] return execute(clauseelement, *multiparams, **params)

    *
      File "/usr/share/pyshared/sqlalchemy/engine/base.py", line 1157, in execute

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] params)

    *
      File "/usr/share/pyshared/sqlalchemy/engine/base.py", line 1237, in _execute_clauseelement

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] return self.__execute_context(context)

    *
      File "/usr/share/pyshared/sqlalchemy/engine/base.py", line 1268, in __execute_context

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] context.parameters[0], context=context)

    *
      File "/usr/share/pyshared/sqlalchemy/engine/base.py", line 1806, in _cursor_execute

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] cursor, statement, parameters, context, False)

    *
      File "/home/josh/Projects/masterpieces_of_code/env/lib/python2.6/site-packages/flaskext/sqlalchemy.py", line 115, in cursor_execute

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] return execute(cursor, statement, parameters, context)

    *
      File "/usr/share/pyshared/sqlalchemy/engine/base.py", line 1367, in _cursor_execute

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] context)

    *
      File "/usr/share/pyshared/sqlalchemy/engine/base.py", line 1360, in _cursor_execute

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] context)

    *
      File "/usr/share/pyshared/sqlalchemy/engine/default.py", line 288, in do_execute

       [Display the sourcecode for this frame]  [Open an interactive python shell in this frame] cursor.execute(statement, parameters)

    IntegrityError: (IntegrityError) column username is not unique u'INSERT INTO user (username, password, karma) VALUES (?, ?, ?)' (u'Test', u'test', 0)

This is the Copy/Paste friendly version of the traceback. You can also paste this traceback into the public lodgeit pastebin:

Traceback (most recent call last):
  File "/home/josh/Projects/masterpieces_of_code/env/lib/python2.6/site-packages/flask/app.py", line 889, in __call__
    return self.wsgi_app(environ, start_response)
  File "/home/josh/Projects/masterpieces_of_code/env/lib/python2.6/site-packages/flask/app.py", line 879, in wsgi_app
    response = self.make_response(self.handle_exception(e))
  File "/home/josh/Projects/masterpieces_of_code/env/lib/python2.6/site-packages/flask/app.py", line 876, in wsgi_app
    rv = self.dispatch_request()
  File "/home/josh/Projects/masterpieces_of_code/env/lib/python2.6/site-packages/flask/app.py", line 695, in dispatch_request
    return self.view_functions[rule.endpoint](**req.view_args)
  File "/home/josh/Projects/masterpieces_of_code/app.py", line 70, in create_user
    db.session.commit()
  File "/usr/share/pyshared/sqlalchemy/orm/scoping.py", line 129, in do
    return getattr(self.registry(), name)(*args, **kwargs)
  File "/usr/share/pyshared/sqlalchemy/orm/session.py", line 653, in commit
    self.transaction.commit()
  File "/usr/share/pyshared/sqlalchemy/orm/session.py", line 364, in commit
    self._prepare_impl()
  File "/usr/share/pyshared/sqlalchemy/orm/session.py", line 348, in _prepare_impl
    self.session.flush()
  File "/usr/share/pyshared/sqlalchemy/orm/session.py", line 1346, in flush
    self._flush(objects)
  File "/usr/share/pyshared/sqlalchemy/orm/session.py", line 1427, in _flush
    flush_context.execute()
  File "/usr/share/pyshared/sqlalchemy/orm/unitofwork.py", line 299, in execute
    rec.execute(self)
  File "/usr/share/pyshared/sqlalchemy/orm/unitofwork.py", line 443, in execute
    uow
  File "/usr/share/pyshared/sqlalchemy/orm/mapper.py", line 1833, in _save_obj
    execute(statement, params)
  File "/usr/share/pyshared/sqlalchemy/engine/base.py", line 1794, in execute
    object, *multiparams, **params)
  File "/usr/share/pyshared/sqlalchemy/interfaces.py", line 149, in execute
    return execute(clauseelement, *multiparams, **params)
  File "/usr/share/pyshared/sqlalchemy/engine/base.py", line 1157, in execute
    params)
  File "/usr/share/pyshared/sqlalchemy/engine/base.py", line 1237, in _execute_clauseelement
    return self.__execute_context(context)
  File "/usr/share/pyshared/sqlalchemy/engine/base.py", line 1268, in __execute_context
    context.parameters[0], context=context)
  File "/usr/share/pyshared/sqlalchemy/engine/base.py", line 1806, in _cursor_execute
    cursor, statement, parameters, context, False)
  File "/home/josh/Projects/masterpieces_of_code/env/lib/python2.6/site-packages/flaskext/sqlalchemy.py", line 115, in cursor_execute
    return execute(cursor, statement, parameters, context)
  File "/usr/share/pyshared/sqlalchemy/engine/base.py", line 1367, in _cursor_execute
    context)
  File "/usr/share/pyshared/sqlalchemy/engine/base.py", line 1360, in _cursor_execute
    context)
  File "/usr/share/pyshared/sqlalchemy/engine/default.py", line 288, in do_execute
    cursor.execute(statement, parameters)
IntegrityError: (IntegrityError) column username is not unique u'INSERT INTO user (username, password, karma) VALUES (?, ?, ?)' (u'Test', u'test', 0)

The debugger caught an exception in your WSGI application. You can now look at the traceback which led to the error.

To switch between the interactive traceback and the plaintext one, you can click on the "Traceback" headline. From the text traceback you can also create a paste of it. For code execution mouse-over the frame you want to debug and click on the console icon on the right side.

You can execute arbitrary Python code in the stack frames and there are some extra helpers available for introspection:

    * dump() shows all variables in the frame
    * dump(obj) dumps all that known about the object

Brought to you by DON'T PANIC, your friendly Werkzeug powered traceback interpreter.

Я забыл упомянуть, как реагирует фляжка, когда я пытаюсь обработать ошибку. Я получаю что-то, связанное с глобальным undefined. Здесь трассировка для этого.

Traceback (most recent call last):
  File "/home/josh/Projects/masterpieces_of_code/env/lib/python2.6/site-packages/flask/app.py", line 889, in __call__
    return self.wsgi_app(environ, start_response)
  File "/home/josh/Projects/masterpieces_of_code/env/lib/python2.6/site-packages/flask/app.py", line 879, in wsgi_app
    response = self.make_response(self.handle_exception(e))
  File "/home/josh/Projects/masterpieces_of_code/env/lib/python2.6/site-packages/flask/app.py", line 876, in wsgi_app
    rv = self.dispatch_request()
  File "/home/josh/Projects/masterpieces_of_code/env/lib/python2.6/site-packages/flask/app.py", line 695, in dispatch_request
    return self.view_functions[rule.endpoint](**req.view_args)
  File "/home/josh/Projects/masterpieces_of_code/app.py", line 72, in create_user
    except(IntegrityError):
NameError: global name 'IntegrityError' is not defined
  • 0
    Я обновил свой ответ в ответ на ваш комментарий.
Теги:
flask
flask-sqlalchemy

1 ответ

9
Лучший ответ

Вам нужно поставить try/catch в вашу create_user функцию (masterpieces_c_code/app.py) в блок кода, который делает db.session.commit(), и обрабатывать там исключение.

Обновление: Если вы получаете NameError для IntegrityError, значит, вы, вероятно, не увидите

from sqlalchemy.exc import IntegrityError

в app.py. Это не сообщение из Flask, что Python сообщает вам о неизвестном имени (из-за отсутствия импорта), поскольку он интерпретирует код в app.py.

  • 0
    Спасибо, я забыл упомянуть, что уже пробовал. По какой-то причине Flask говорит, что IntegrityError является неопределенным глобальным. Я обновил свою исходную публикацию, чтобы отразить это.
  • 0
    Сладкий, спасибо. Я довольно новичок в Python.

Ещё вопросы

Сообщество Overcoder
Наверх
Меню