I'm using python flask as a backend, running it as a service in the GCP instance. It is working correctly once started the service. But after a day when I try to make an API call it losses its connection with MySQL and shows the following
error mysql.connector.errors.InterfaceError: 2013:
I tried using pymysql and mysql.connector but facing the same error. Is there any way to solve this?
Related
I'm newbie running a Flask app connected to a MySQL remote server with Flask-SQLAlchemy.
The app has very little traffic and it's usual to stay idle for more than 8 hours, I then get disconnected from the MySQL server.
this is my app code:
from flask import Flask, render_template, request, redirect, jsonify, make_response
from flask_sqlalchemy import SQLAlchemy
from sqlalchemy import or_
app = Flask(__name__)
app.config['DEBUG'] = True
app.config['SQLALCHEMY_ENGINE_OPTIONS'] = {'pool_pre_ping': True, 'pool_recycle': 300, 'echo':'debug',}
app.config['SQLALCHEMY_DATABASE_URI']='mysql+pymysql://user:pass#myipcode/db'
db = SQLAlchemy(app)
Everything works ok until no querys are performed for 8 hours, then I lose db connection and logs show this error code:
"MySQL server has gone away (%r)" % (e,)) sqlalchemy.exc.OperationalError: (pymysql.err.OperationalError) (2006, "MySQL server has gone away (BrokenPipeError(32, 'Broken pipe'))
I did some research and was adviced to set 'SQLALCHEMY_ENGINE_OPTIONS' as written in the code sample but it behaves the same with or without such engine options, connection is not recycled every 300 seconds as It should, and pool_pre_ping doesn't seem to make any difference. 'echo':'debug' option works as intended since I get every transaction logged.
What should I do to prevent the connection from being disconnected even after a long period of inactivty?
EDIT:
To add some additional info:
The database is hosted in Cloud SQL from GCP .
I'm lost...
Any help would be greatly appreciated.
Finally I figured it out myself,
It had to do with the fact that my app was running on a mountpoint like http://ServerIP/app instead of http://ServerIP/ because it was initially intended as a staging server.
I was using uWSGI and, in order to make it work in the aforementioned path, I had to specify a mount parameter in the [UWSGI] block from app.ini file.
When the uWSGI server started it showed like it was mounting two apps, one in '' and the other in '/app', and I guess that created a conflict that made the app unable to manage connections on MySQL server.
Mounting the app in http://ServerIP/ worked like a charm.
I am trying to run a SQL script from MySQL workbench, and have it import data to Cloud SQL using Cloud SQL Client proxy. This SQL script is about 10 GB. I have tried this a few times, and it takes too long, and says the certification of the connection will expire soon. Soon after that, the so the connection ends, and I see an error on workbench saying lost connection to MySQL server.
Are there any suggestions on what I should do / do different?
I am not wanting to use Cloud SQL Buckets to import data, and hence am going the route of Cloud SQL Client.
Your connection ended error can be due to many different reasons. One being your script is too large and is causing the connection to timeout. I would suggest splitting your script and importing them separately.
It is possible that the “certification of the connection will expire soon” error can be resolved by rotating your server certificates. You can find how to do that here: https://cloud.google.com/sql/docs/mysql/manage-ssl-instance#manage-server-certs
I am trying to connect superset 0.23.3 which is in hdp to sql server 2014(local machine) through sqlalchemy but facing an error regarding no module found. Attachments of my sqlalchemy connection string and error is given below:
This is the image of my connection string and it is correct as i ran this string in spyder and successfully connected with sql server
Error i am getting after clicking on test connection button
As it is saying in error no module found but it is already installed in site-packages under C:\Python36\Lib\
Already installed in site-packages folder
Connected sql server with python via sqlalchemy
Any help is highly appreciated. Thanks in advance
I am currently trying to connect to my MySql database created on AWS with a python program using the library PyMySQL.
import pymysql.cursors
connection = pymysql.connect(host='.blablablablabla.us-east.rds.amazonaws.com',
user='Username',
password='Password',
db='nameofmydb',
)
When I run the above code I get the following error:
pymysql.err.InternalError: (1049, "Unknown database 'nameofmydb'")
What am I doing wrong? The arguments I gave to the function are correct. Could it be a problem with the MySql driver?
Thank you in advance
The message is the standard one, returned by mysql server. It means what it says, it can not find the database. Doesn't look like a connectivity problem or a driver issue: it reaches the server and the server returns a message.
Just make sure you have created the database using the CREATE DATABASE command. Use the mysql CLI client to connect to the database and type SHOW DATABASES to see all the available databases.
Im having trouble connecting to my sql server on digital ocean through my flask webapp. Im using flask-sqlalchemy to bind the mysql database to Flask.
Im able to access the mysql server through the phpmyadmin interface at myipaddress:5000/phpmyadmin
Since Im using Nginx (I bound it to port 80). Bound Apache to Port 5000. So my phpmyadmin interface is accessible at
myipaddress:5000/phpmyadmin
In my flask app, i specify the
SQLALCHEMY_DATABASE_URI ='mysql://root:password#myipaddress:5000/databasename'
when i try to create the tables on my database using the shell with db.create_all() - it just doesnt respond. The cursor blinks forever and then i get the operational error that i quote on the title afte a few minutes
Im able to get the same setup running on my local dev machine. So i know its not a flask configuration problem but just a mysql access issue. I have my webapp up on digitalocean (Not sure if mysql server is behind a firewall or something like that making it inaccessible
On the
/etc/mysql/my.cnf
for the bind-address under mysql_d section, i tried all possible combinations and restarted the mysql server with no success
i tried localhost, 127.0.0.1, 127.0.0.1:5000, myipaddress for the bind-address (Also tried commenting it out) without any results.
Also i tried to get the user, current_user on the table properties from the mysql command line, it's listed as root#localhost for both
From this post:Lost connection to MySQL server at 'reading initial communication packet', system error: 0; i get the idea that its related to firewall but not sure how to rectify this.
Anyidea how can i connect my flask app to the mysql server ? Any help would be much appreciated
I was specifying the mysql address as
mysql://root:password#myipaddress:5000/databasename
But since my flask app and the mysql server are running on the same server, the flask app was be able to access the mysql server when i replaced the myipaddress:5000 with localhost:5000
mysql://root:password#localhost:5000/databasename
The phpmyadmin is just a web interface for your database, if you're looking at connecting your Flask application to your MySql database, you need to point the SQLALCHEMY_DATABASE_URI to the actual MySQL database, rather then the web interface to that database.
Usually MySql runs on port 3306. I believe that SQLAlchemy is clever enough to know that's the default, so your connection string should just be: SQLALCHEMY_DATABASE_URI ='mysql://root:password#localhost/databasename' or if you are running on a different port/external IP address: SQLALCHEMY_DATABASE_URI ='mysql://root:password#myipaddress:4444/databasename'. Remember, if you're connecting to a MySQL database on an external server (not the same one as your Flask app is running on) you will have to change the configuration to allow that kind of access.