Service stopped when MySQL server restarted

[indrarudia]

When MySQL server restarted, vaisala-bbd Supervisor process failed to restart. It caused the service to stop and not receiving data from telnet server which make the data continue to stop.

Supervisor log:

cendana15@apicendana15:~/GitLab/bpptkg-meteo/examples/vaisala-bbd$ tail /var/log/supervisor/vaisala-bbd-error.log

Output:

  File "/home/cendana15/GitLab/bpptkg-meteo/examples/vaisala-bbd/venv/lib/python3.6/site-packages/sqlalchemy/engine/create.py", line 578, in connect
    return dialect.connect(*cargs, **cparams)
  File "/home/cendana15/GitLab/bpptkg-meteo/examples/vaisala-bbd/venv/lib/python3.6/site-packages/sqlalchemy/engine/default.py", line 583, in connect
    return self.dbapi.connect(*cargs, **cparams)
  File "/home/cendana15/GitLab/bpptkg-meteo/examples/vaisala-bbd/venv/lib/python3.6/site-packages/MySQLdb/__init__.py", line 130, in Connect
    return Connection(*args, **kwargs)
  File "/home/cendana15/GitLab/bpptkg-meteo/examples/vaisala-bbd/venv/lib/python3.6/site-packages/MySQLdb/connections.py", line 185, in __init__
    super().__init__(*args, **kwargs2)
sqlalchemy.exc.OperationalError: (MySQLdb._exceptions.OperationalError) (2002, "Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)")
(Background on this error at: http://sqlalche.me/e/14/e3q8)

Although that we can easily restart the service using sudo supervisorctl restart vaisala-bbd, it is more convenient that the service itself can detect the error as we rarely monitor the service whether is up or not in the server.