Updating the webpage using Flask based on MySQL database.


I have a webpage (built using HTML & jQuery) which displays the data from a MySQL database. I am using Flask to connect HTML with my database. However, my database gets updated every 15 minutes (using a separate Python Script). Currently, I stop the flask server, update the database and restart the Flask to update the webpage. My question is the following:

Is there a way to update the MySQL database in the background without having to stop the flask server? I read about concepts of AJAX and CRON, however i am not able to understand how to use them with flask asynchronously.

Note: I am a newbie in web applications and this is my first project which involves connecting client side and server side. Any help will be appreciated.


2/14/2013 8:24:33 AM

Accepted Answer

You are most likely doing something like this:

from flask import Flask, render_template
from yourMySqlLibrary import connect_to_mysql

conn = connect_to_mysql()
# This is only executed when you start the script
data = conn.execute("SELECT * FROM MySemiRegularlyUpdatedTable")

app = Flask(__name__)

def view_data():
    return render_template("view_data.html", data=data)

if __name__ == "__main__":

If that is the case, then your solution is simply to move your connection and query calls into your controller so that the database is re-queried every time you hit the page:

def view_data():
    # Removed from above and placed here
    # The connection is made to the database for each request
    conn = connect_to_mysql()
    # This is only executed on every request
    data = conn.execute("SELECT * FROM MySemiRegularlyUpdatedTable")
    return render_template("view_data.html", data=data)

This way, your view will update when your data does - and you won't have to restart the server just to pick up changes to your data.

2/15/2013 2:34:17 AM

Licensed under: CC-BY-SA with attribution
Not affiliated with: Stack Overflow