python - reconnect keyword argument on ClearDB default connection string causing errors with MySQLdb

Question

I uploaded a Django app to Heroku and than provision the cleardb add-on using these 3 commands from Heroku documentation:

heroku addons:create cleardb:ignite
heroku config | grep CLEARDB_DATABASE_URL
heroku config:set DATABASE_URL='mysql://adffdadf2341:[email protected]/heroku_db?reconnect=true'

it seems to be O.K and the app is running (but without database). now I try to run:

$ heroku run python manage.py migrate

and this is the error I get:

Traceback (most recent call last):
  File "manage.py", line 22, in <module>
    execute_from_command_line(sys.argv)
  File "/app/.heroku/python/lib/python3.5/site-packages/django/core/management/__init__.py", line 363, in execute_from_command_line
    utility.execute()
  File "/app/.heroku/python/lib/python3.5/site-packages/django/core/management/__init__.py", line 355, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/app/.heroku/python/lib/python3.5/site-packages/django/core/management/base.py", line 283, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/app/.heroku/python/lib/python3.5/site-packages/django/core/management/base.py", line 327, in execute
    self.check()
  File "/app/.heroku/python/lib/python3.5/site-packages/django/core/management/base.py", line 359, in check
    include_deployment_checks=include_deployment_checks,
  File "/app/.heroku/python/lib/python3.5/site-packages/django/core/management/commands/migrate.py", line 61, in _run_checks
    issues = run_checks(tags=[Tags.database])
  File "/app/.heroku/python/lib/python3.5/site-packages/django/core/checks/registry.py", line 81, in run_checks
    new_errors = check(app_configs=app_configs)
  File "/app/.heroku/python/lib/python3.5/site-packages/django/core/checks/database.py", line 10, in check_database_backends
    issues.extend(conn.validation.check(**kwargs))
  File "/app/.heroku/python/lib/python3.5/site-packages/django/db/backends/mysql/validation.py", line 9, in check
    issues.extend(self._check_sql_mode(**kwargs))
  File "/app/.heroku/python/lib/python3.5/site-packages/django/db/backends/mysql/validation.py", line 13, in _check_sql_mode
    with self.connection.cursor() as cursor:
  File "/app/.heroku/python/lib/python3.5/site-packages/django/db/backends/base/base.py", line 254, in cursor
    return self._cursor()
  File "/app/.heroku/python/lib/python3.5/site-packages/django/db/backends/base/base.py", line 229, in _cursor
    self.ensure_connection()
  File "/app/.heroku/python/lib/python3.5/site-packages/django/db/backends/base/base.py", line 213, in ensure_connection
    self.connect()
  File "/app/.heroku/python/lib/python3.5/site-packages/django/db/backends/base/base.py", line 189, in connect
    self.connection = self.get_new_connection(conn_params)
  File "/app/.heroku/python/lib/python3.5/site-packages/django/db/backends/mysql/base.py", line 274, in get_new_connection
    conn = Database.connect(**conn_params)
  File "/app/.heroku/python/lib/python3.5/site-packages/MySQLdb/__init__.py", line 86, in Connect
    return Connection(*args, **kwargs)
  File "/app/.heroku/python/lib/python3.5/site-packages/MySQLdb/connections.py", line 204, in __init__
    super(Connection, self).__init__(*args, **kwargs2)
TypeError: 'reconnect' is an invalid keyword argument for this function

Where does the problem comes from and how can I fix it?

Answer 1

Remove ?reconnect=true from the end of DATABASE_URL

The parameters after the database are arguments to the MySQL server. In this case, it asks to reconnect if the connection is dropped. It looks like the MySQLdb package doesn't support that argument.