bebetterthinker / Django-crud-application

Django CRUD (Create Read Update Delete) Example. This project contains creating table using ORM, listing, fetching, editing and deleting data from and to database

Django CRUD (Create Read Update Delete) Example

This project contains-

• creating table using ORM
• listing, fetching, editing and deleting data from and to database

For step by step guide open file- stepBystep.docs

Prerequisites before using Django- basic knowledge of python, html, css and Applications need to install- Python and python virtual environment

a. Download and Install python

b. Create virtual environment(pip should be installed(check version- pip --version)) Install either virtualenvwrapper or virtualenv(for more info goto- link) install virtual environment- pip install virtualenv Create virtual environment- virtualenv Now activate virtual env - cd /Scripts/activate

c. Install Django using command - pip install django Check django version command- python -m django --version

To create a Django application that performs CRUD operations, follow the following steps.

1. Create a Project, using command- $ django-admin startproject crudexample

2. Create an App, using command- $ python3 manage.py startapp employee

3. Database Setup - Create a database djangodb in mysql, and configure into the settings.py file of django project. See the example. // settings.py DATABASES = {
   'default': {
   'ENGINE': 'django.db.backends.mysql',
   'NAME': 'djangodb',
   'USER':'root',
   'PASSWORD':'mysql',
   'HOST':'localhost',
   'PORT':'3306'
   }
   }

4. Create a Model- Put the following code into models.py file. // models.py from django.db import models
   class Employee(models.Model):
   eid = models.CharField(max_length=20)
   ename = models.CharField(max_length=100)
   eemail = models.EmailField()
   econtact = models.CharField(max_length=15)
   class Meta:
   db_table = "employee"

5. Create a ModelForm // forms.py from django import forms
   from employee.models import Employee
   class EmployeeForm(forms.ModelForm):
   class Meta:
   model = Employee
   fields = "all"

6. Create View Functions // views.py from django.shortcuts import render, redirect
   from employee.forms import EmployeeForm
   from employee.models import Employee

Create your views here.

def emp(request):
if request.method == "POST":
form = EmployeeForm(request.POST)
if form.is_valid():
try:
form.save()
return redirect('/show')
except:
pass
else:
form = EmployeeForm()
return render(request,'index.html',{'form':form})

def show(request):
employees = Employee.objects.all()
return render(request,"show.html",{'employees':employees})

def edit(request, id):
employee = Employee.objects.get(id=id)
return render(request,'edit.html', {'employee':employee})

def update(request, id):
employee = Employee.objects.get(id=id)
form = EmployeeForm(request.POST, instance = employee)
if form.is_valid():
form.save()
return redirect("/show")
return render(request, 'edit.html', {'employee': employee})

def destroy(request, id):
employee = Employee.objects.get(id=id)
employee.delete()
return redirect("/show")

7. Provide Routing Provide URL patterns to map with views function. // urls.py from django.contrib import admin
   from django.urls import path
   from employee import views
   urlpatterns = [
   path('admin/', admin.site.urls), path('', include('employee.urls')), ]

8. Creating routing for employee urls // employee/urls.py from django.urls import path from . import views

urlpatterns = [ path('', views.show), path('emp', views.emp), path('show', views.show), path('edit/int:id', views.edit), path('update/int:id', views.update), path('delete/int:id', views.destroy), ]

9. Organize Templates

create a base template for all files- templates/base.html To tell django about this file, do some changes in settings.py- TEMPLATES = [ { 'BACKEND': 'django.template.backends.django.DjangoTemplates', 'DIRS': [os.path.join(BASE_DIR, 'templates')], 'APP_DIRS': True, 'OPTIONS': { 'context_processors': [ 'django.template.context_processors.debug', 'django.template.context_processors.request', 'django.contrib.auth.context_processors.auth', 'django.contrib.messages.context_processors.messages', ], }, }, ]

Create a templates folder inside the main project and create base.html file there- // base.html Now a create a templates folder inside employee app and create three (index, edit, show) html files inside the directory. files are- // index.html // show.html //edit.html

10. Now create css, create a static/css folder in main directory parallel to manage.py and create a file style.css in it. changes to do at the end of settings.py- STATICFILES_DIRS = [ os.path.join(BASE_DIR, 'static') ] STATIC_ROOT = os.path.join(BASE_DIR, 'assets')

and now tell djnago about your css file, run command- python manage.py collectstatic (it will create a folder assets in main directory with your css file in it. You should run this command always after making changes in your css, js or images.)

11. Create Migrations Create migrations for the created model employee, use the following command. $ python3 manage.py makemigrations
    After migrations, execute one more command to reflect the migration into the database. But before it, mention name of app (employee) in INSTALLED_APPS of settings.py file. // settings.py INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'employee'
    ]

Run the command to migrate the migrations. $ python3 manage.py migrate

Now, our application has successfully connected and created tables in database. It creates 10 default tables for handling project (session, authentication etc) and one table of our model that we created. See list of tables created after migrate command.

Run Server To run server use the following command. $ python3 manage.py runserver

Access to the Browser Access the application by entering localhost:8000/, it will show all the available employee records. Initially, there is no record. So, it shows no record message. Well, we have successfully created a CRUD application using Django. This complete project can be downloaded here.( https://github.com/diwamishra21/Django-crud-application)

12. Accessing admin panel, for that you have to create a super user using command- python manage.py createsuperuser (than follow instructions)

Debugging/basic errors-

1. MySQL connection Error- Solution- django.core.exceptions.ImproperlyConfigured: Error loading MySQLdb module. Did you install mysqlclient? Ans- pip install pymysql Then, edit the init.py file in your project origin dir(the same as settings.py) add: import pymysql pymysql.install_as_MySQLdb()

2. 'staticfiles' is not a registered tag library Solution- It's due to upgrading to Django3.0, use as mentioned above. use- {% load static %}