pythonhtmlsqliteflaskhttp-status-code-404
How to prevent data from disappearing when refreshing web page?
In app.py I established a connection with my database then retrieved the data and stored it in a cursor object. I want to show the data on a web page so I transferred it with :
render_template('home.html', data=cursor)
Which works, it shows the data on my web page but when I refresh the page I get :
GET http://127.0.0.1:5000/static/css/template.css net::ERR_ABORTED 404 (NOT FOUND)
and my data doesn't show anymore.
app.py :
from flask import Flask, render_template
import sqlite3
import os.path
app = Flask(__name__)
BASE_DIR = os.path.dirname(os.path.abspath(__file__))
db_path = os.path.join(BASE_DIR, "movies.db")
with sqlite3.connect(db_path, check_same_thread=False) as db:
#I used check_same_thread=False to solve a same thread error
cursor = db.cursor()
cursor.execute("SELECT * FROM data")
@app.route("/")
def home():
return render_template('home.html', data=cursor)
if __name__== "__main__":
app.run(debug=True)
A piece of home.html :
<body>
{% extends "template.html" %}
{% block content %}
{% for item in data %}
<tr>
<td><a>{{item[1]}}</a></td>
</tr>
{% endfor %}
{% endblock %}
</body>
I want my web page to show the data without disappearing when I refresh my page.
Solution
According to the official documentation as @Fian suggested, you need to open the database connection on demand and close them when the context dies.
Updated code for app.py:
import os
import sqlite3
from flask import Flask, render_template, g
app = Flask(__name__)
BASE_DIR = os.path.dirname(os.path.abspath(__file__))
DATABASE = os.path.join(BASE_DIR, "movies.db")
def get_db():
db = getattr(g, '_database', None)
if db is None:
db = g._database = sqlite3.connect(DATABASE)
return db
@app.teardown_appcontext
def close_connection(exception):
db = getattr(g, '_dattabase', None)
if db is not None:
db.close()
@app.route('/')
def index():
cur = get_db().cursor()
cur.execute('SELECT * FROM data')
rows = cur.fetchall()
return render_template('index.html', rows = rows)
if __name__ == '__main__':
app.run(debug = True)
index.html:
<html>
<head>
<title>SQLite in Flask</title>
</head>
<body>
<h1>Movies</h1>
{% if rows %}
<ul>
{% for row in rows %}
<li>{{ row[0] }}</li>
{% endfor %}
</ul>
{% endif %}
</body>
</html>
Output:
Reference: