Flask CRUD Application Flash Messages

Flask CRUD

About Lesson

In this Flask CRUD Application lesson we are going to learn about Flask CRUD Application Flash Messages, Flask provides a really simple way to give feedback to a user with the flashing message system. The flashing system basically makes it possible to record a message at the end of a request and access it next request and only next request. This is usually combined with a layout template that does this. Note that browsers and sometimes web servers enforce a limit on cookie sizes. This means that flashing messages that are too large for session cookies causes message flashing to fail silently.

Open your App.py file and in the insert method add your Flash Message in flask.

@app.route('/insert', methods=['POST'])
def insert():
    if request.method == 'POST':
        name = request.form['name']
        email = request.form['email']
        phone = request.form['phone']

        my_data = Data(name, email, phone)
        db.session.add(my_data)
        db.session.commit()
        
        flash("Employee Inserted Successfully")

        return redirect(url_for('Index'))

@app.route('/insert', methods=['POST'])

def insert():

if request.method == 'POST':

name = request.form['name']

email = request.form['email']

phone = request.form['phone']

my_data = Data(name, email, phone)

db.session.add(my_data)

db.session.commit()

flash("Employee Inserted Successfully")

return redirect(url_for('Index'))

This is the complete code for App.py file.

from flask import Flask, render_template, redirect, flash, \
    request, url_for
from flask_sqlalchemy import SQLAlchemy




#create the object of Flask
app  = Flask(__name__)
app.secret_key = "geekscoderssecretkey"
#SqlAlchemy Database Configuration With Mysql
app.config['SQLALCHEMY_DATABASE_URI'] = 'mysql://root:''@localhost/crud'
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False


db = SQLAlchemy(app)


# Creating model table for our CRUD database
class Data(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(100))
    email = db.Column(db.String(100))
    phone = db.Column(db.String(100))

    def __init__(self, name, email, phone):
        self.name = name
        self.email = email
        self.phone = phone


#creating our routes
@app.route('/')
def Index():
    return render_template("index.html")


# this route is for inserting data
# to mysql database via html forms
@app.route('/insert', methods=['POST'])
def insert():
    if request.method == 'POST':
        name = request.form['name']
        email = request.form['email']
        phone = request.form['phone']

        my_data = Data(name, email, phone)
        db.session.add(my_data)
        db.session.commit()

        flash("Employee Inserted Successfully")

        return redirect(url_for('Index'))

#run flask app
if __name__ == "__main__":
    app.run(debug=True)

from flask import Flask, render_template, redirect, flash, \

request, url_for

from flask_sqlalchemy import SQLAlchemy

#create the object of Flask

app = Flask(__name__)

app.secret_key = "geekscoderssecretkey"

#SqlAlchemy Database Configuration With Mysql

app.config['SQLALCHEMY_DATABASE_URI'] = 'mysql://root:''@localhost/crud'

app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False

db = SQLAlchemy(app)

# Creating model table for our CRUD database

class Data(db.Model):

id = db.Column(db.Integer, primary_key=True)

name = db.Column(db.String(100))

email = db.Column(db.String(100))

phone = db.Column(db.String(100))

def __init__(self, name, email, phone):

self.name = name

self.email = email

self.phone = phone

#creating our routes

@app.route('/')

def Index():

return render_template("index.html")

# this route is for inserting data

# to mysql database via html forms

@app.route('/insert', methods=['POST'])

def insert():

if request.method == 'POST':

name = request.form['name']

email = request.form['email']

phone = request.form['phone']

my_data = Data(name, email, phone)

db.session.add(my_data)

db.session.commit()

flash("Employee Inserted Successfully")

return redirect(url_for('Index'))

#run flask app

if __name__ == "__main__":

app.run(debug=True)

Now we need to show our flash message so open your index.html file, and add this code after the Add button.

                {% with messages = get_flashed_messages() %}
 
                {% if messages %}
 
                {% for message in messages %}
 
                <div class="alert alert-success alert-dismissable" role="alert">
 
                    <button type="button" class="close" data-dismiss="alert" aria-label="close">
 
                        <span aria-hidden="true">x</span>
 
                    </button>
 
 
                {{message}}
 
 
                </div>
 
 
                {% endfor %}
 
                {% endif %}
                {% endwith %}

{% with messages = get_flashed_messages() %}

{% if messages %}

{% for message in messages %}

</button>

</div>

{% endfor %}

{% endif %}

{% endwith %}

This is the complete code for index.html.

{% extends 'base.html' %}
{% include 'header.html' %}


{% block title %}Flask CRUD Application {% endblock %}


{% block body %}

<div class="container">
  <div class="row">
    <div class="col md-12">
      <div class="jumbotron p-3">
        <h2>Manage <b>Employees </b>
          <button class="btn btn-success float-right" data-target="#mymodal"
                  data-toggle="modal" type="button">Add New Employees
          </button>
        </h2>


                {% with messages = get_flashed_messages() %}

                {% if messages %}

                {% for message in messages %}

                <div class="alert alert-success alert-dismissable" role="alert">

                    <button type="button" class="close" data-dismiss="alert" aria-label="close">

                        <span aria-hidden="true">x</span>

                    </button>


                {{message}}


                </div>


                {% endfor %}

                {% endif %}
                {% endwith %}

        <table class="table table-hover table-dark">

          <tr>

            <th>ID</th>
            <th>Name</th>
            <th>Email</th>
            <th>Phone</th>
            <th>Action</th>

          </tr>

          <tr>
            <td>01</td>
            <td>Geekscoders</td>
            <td>geeks@gmail.com</td>
            <td>858558</td>

            <td>
              <a class="btn btn-warning btn-xs" data-target="#modaledit"
                 data-toggle="modal" href="">
                Edit</a>
              <a class="btn btn-danger btn-xs" href=""
                 onclick="return confirm('Are You Sure To Delete ?')">
                Delete
              </a>

            </td>
          </tr>

          <!-- Modal Edit Employee-->
          <div class="modal fade" id="modaledit" role="dialog">
            <div class="modal-dialog">
              <div class="modal-content">
                <div class="modal-header">
                  <h4 class="modal-title">Update Information</h4>


                </div>

                <div class="modal-body">


                  <form action="" method="POST">


                    <div class="form-group">


                      <label>Name:</label>
                      <input name="id" type="hidden" value="">

                      <input class="form-control" name="name" type="text" value="Geekscoders">


                    </div>


                    <div class="form-group">

                      <label>Email:</label>

                      <input class="form-control" name="email" type="text" value="geeks@gmail.com">


                    </div>


                    <div class="form-group">

                      <label>Phone:</label>
                      <input class="form-control" name="phone" type="text" value="858558">
                    </div>

                    <div class="form-group">

                      <button class="btn btn-primary" type="submit">Update</button>
                    </div>

                  </form>

                </div>

                <div class="modal-footer">
                  <button class="btn btn-secondary" data-dismiss="modal" type="button">Close</button>
                </div>
              </div>
            </div>
          </div>

        </table>
      </div>


      <!-- Modal Add Employee-->
      <div class="modal fade" id="mymodal" role="dialog">
        <div class="modal-dialog">
          <div class="modal-content">
            <div class="modal-header">

              <h4 class="modal-title">Add Employee</h4>
            </div>
            <div class="modal-body">
              <form action="{{url_for('insert')}}" method="POST">
                <div class="form-group">
                  <label>Name:</label>
                  <input class="form-control" name="name" required="1" type="text">
                </div>
                <div class="form-group">
                  <label>Email:</label>
                  <input class="form-control" name="email" required="1" type="email">

                </div>
                <div class="form-group">
                  <label>Phone:</label>
                  <input class="form-control" name="phone" required="1" type="number">
                </div>
                <div class="form-group">
                  <button class="btn btn-primary" type="submit">Add Employee</button>
                </div>
              </form>
            </div>
            <div class="modal-footer">
              <button class="btn btn-secondary" data-dismiss="modal" type="button">Close</button>
            </div>
          </div>
        </div>
      </div>
    </div>
  </div>
</div>


{% endblock %}

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{% extends 'base.html' %}

{% include 'header.html' %}

{% block title %}Flask CRUD Application {% endblock %}

{% block body %}

<h2>Manage <b>Employees </b>

<button class="btn btn-success float-right" data-target="#mymodal"

data-toggle="modal" type="button">Add New Employees

</button>

</h2>

{% with messages = get_flashed_messages() %}

{% if messages %}

{% for message in messages %}

</button>

</div>

{% endfor %}

{% endif %}

{% endwith %}

<tr>

<th>Email</th>

<th>Phone</th>

<th>Action</th>

</tr>

<tr>

<td>Geekscoders</td>

<td>geeks@gmail.com</td>

<td>

<a class="btn btn-warning btn-xs" data-target="#modaledit"

data-toggle="modal" href="">

Edit</a>

<a class="btn btn-danger btn-xs" href=""

onclick="return confirm('Are You Sure To Delete ?')">

Delete

</a>

</td>

</tr>

<h4 class="modal-title">Update Information</h4>

</div>

</div>

<label>Email:</label>

</div>

<label>Phone:</label>

</div>

<button class="btn btn-primary" type="submit">Update</button>

</div>

</form>

</div>

<button class="btn btn-secondary" data-dismiss="modal" type="button">Close</button>

</div>

</table>

</div>

<h4 class="modal-title">Add Employee</h4>

</div>

</div>

<label>Email:</label>

</div>

<label>Phone:</label>

</div>

<button class="btn btn-primary" type="submit">Add Employee</button>

</div>

</form>

</div>

<button class="btn btn-secondary" data-dismiss="modal" type="button">Close</button>

</div>

{% endblock %}

templates/base.html

<!DOCTYPE html>
<html lang="en">
<head>


<link rel="stylesheet"
href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css">

    <meta charset="UTF-8">
    <title>{% block title %} {% endblock %} </title>
</head>
<body>

{% block body %} {% endblock %}


<script
 src="https://code.jquery.com/jquery-3.4.1.slim.min.js">
</script>
<script
src="https://cdn.jsdelivr.net/npm/popper.js@1.16.0/dist/umd/popper.min.js">
</script>
<script
src="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/js/bootstrap.min.js">

</script>

</body>
</html>

<!DOCTYPE html>

<head>

href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css">

<title>{% block title %} {% endblock %} </title>

</head>

<body>

{% block body %} {% endblock %}

<script

src="https://code.jquery.com/jquery-3.4.1.slim.min.js">

</script>

<script

src="https://cdn.jsdelivr.net/npm/popper.js@1.16.0/dist/umd/popper.min.js">

</script>

<script

src="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/js/bootstrap.min.js">

</script>

</body>

</html>

templates/header.html

{% extends 'base.html' %}



{% block title %} Flask CRUD {% endblock %}



{% block body %}

<div class="jumbotron p-3">
    <div class="well text-center">

        <h1>Flask CRUD Application - Geekscoders.com</h1>

    </div>


</div>


{% endblock %}

{% extends 'base.html' %}

{% block title %} Flask CRUD {% endblock %}

{% block body %}

<h1>Flask CRUD Application - Geekscoders.com</h1>

</div>

{% endblock %}

Run your application and add new data, you can see the flash message.