如何将 python 连接到 MySQL 服务器

Question

I coded a CRUD Python API with flask and MySQL. The source code is located in local system and the MySQL database is located on a real network host.

Is it possible to connect local python code to MySQL on a real network host?

here is config.py

from app import app
from flask_mysqldb import MySQL

mysql = MySQL()
app.config['MYSQL_HOST'] = 'http://test.com:5000'
app.config['MYSQL_USER'] = 'guest'
app.config['MYSQL_PASSWORD'] = '12345'
app.config['MYSQL_DB'] = 'school'
mysql.init_app(app)

main.py:

from flask import request, jsonify, redirect, url_for
from app import app
from config import MySQL


@app.route('/list')
def home():
try:
    cursor = mysql.connection.cursor()
    cursor.execute("SELECT * FROM student")
    row_headers = [x[0] for x in cursor.description]
    studentsRows = cursor.fetchall()
    json_data = []
    for result in studentsRows:
        json_data.append(dict(zip(row_headers, result)))
    response = jsonify(student_list=json_data, status=120)
    response.status_code = 200
    return response
 except Exception as e:
    print(e)

@app.errorhandler(404)
def not_found(error=None):
message = {
    'status': 404,
    'message': 'Record not found: ' + request.url,
}
response = jsonify(message)
response.status_code = 404
return response


if __name__ == '__main__':
app.run(host="0.0.0.0")

Answer 1

It's definitely possible to connect from different location to your database.

It's actually the main feature of server based database systems as what mysql or for example postgresql is. Compare that to something like sqlite which is a simple file based database system.

There is but a simple requirement to it - the server has to be network accessible from your current network.

This means few things:

• The server's IP has to be accessible from your network - it either has to have public internet IP assigned or be accessible thru VPN network. Example of bad setup:
  • Server is running on friend's home computer and he doesn't have public IP nor does his ISP allow port forwarding.
• Connection from your network to the server's network must not be blocked by local firewalls (enterprise networks can have strict setups) or by the server's firewall itself.
• The database has to be configured to listen for these outside connections. Most of these servers, by default, listen only on local network/interface.
• Proper security measures should be in-place. Opening the database to the whole internet is considered pretty insecure as it allows anyone to fiddle with it (password bruteforce, bug explotation...). You should have strong password and at least IP whitelist in-place.

Please see the mysql manual , also there is a bunch of tutorials how to setup this, simple google search should work.

EDIT: As to your code example, please see flask_mysql documentation on how to connect to server, you will probably be most interested in the 'MYSQL_HOST' value, though all the other values (user, pass, port, dbname) have to match what is configured on your server.