CRUD in Django

Simplest CRUD example

If you find these steps unfamiliar, consider starting here instead. Note these steps come from Stack Overflow Documentation.

django-admin startproject myproject
cd myproject
python manage.py startapp myapp

myproject/settings.py Install the app

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'myapp',
]

Create a file called urls.py within the myapp directory and updated it with the following view.

from django.conf.urls import url
from myapp import views

urlpatterns = [
    url(r'^$', views.index, name='index'),
    ]

Update the other urls.py file with the following content.

from django.conf.urls import url
from django.contrib import admin
from django.conf.urls import include 
from myapp import views

urlpatterns = [
    url(r'^$', views.index, name='index'),
    url(r'^myapp/', include('myapp.urls')),
    url(r'^admin/', admin.site.urls),
]

Create a folder named templates within the myapp directory. Then create a file named index.html inside of the templates directory. Fill it with the following content.

<!DOCTYPE html>
<html>
<head>
    <title>myapp</title>
</head>
<body>
    <h2>Simplest Crud Example</h2>
    <p>This shows a list of names and lets you Create, Update and Delete them.</p>
    <h3>Add a Name</h3>
    <button>Create</button>
</body>
</html>

We also need a view to show index.html which we can create by editing the views.py file like so:

from django.shortcuts import render, redirect

# Create your views here.
def index(request):
    return render(request, 'index.html', {})

You now have the base that you’re going to work off of. The next step is create a Model. This is the simplest example possible so in your models.py folder add the following code.

from __future__ import unicode_literals

from django.db import models

# Create your models here.
class Name(models.Model):
    name_value = models.CharField(max_length=100)

    def __str__(self): # if Python 2 use __unicode__
        return self.name_value

This creates a model of a Name object which we’ll add to the database with the following commands from the command line.

python manage.py createsuperuser 
python manage.py makemigrations
python manage.py migrate

You should see some operations performed by Django. These setup up the tables and create a superuser that can access the admin database from a Django powered admin view. Speaking of which, lets register our new model with the admin view. Go to admin.py and add the following code.

from django.contrib import admin
from myapp.models import Name
# Register your models here.

admin.site.register(Name)

Back at the command line you can now spin up the server with the python manage.py runserver command. You should be able to visit https://localhost:8000/ and see your app. Please then navigate to https://localhost:8000/admin so that you can add a name to your project. Log in and add a Name under the MYAPP table, we kept it simple for the example so ensure it’s less than 100 characters.

In order to access the name you need to display it somewhere. Edit the index function within views.py to get all of the Name objects out of the database.

from django.shortcuts import render, redirect
from myapp.models import Name

# Create your views here.
def index(request):
    names_from_db = Name.objects.all()
    context_dict = {'names_from_context': names_from_db}
    return render(request, 'index.html', context_dict)

Now edit the index.html file to the following.

<!DOCTYPE html>
<html>
<head>
    <title>myapp</title>
</head>
<body>
    <h2>Simplest Crud Example</h2>
    <p>This shows a list of names and lets you Create, Update and Delete them.</p>
    {% if names_from_context %}
        <ul>
            {% for name in names_from_context %}
                <li>{{ name.name_value }}  <button>Delete</button> <button>Update</button></li>
            {% endfor %}
        </ul>
    {% else %}
        <h3>Please go to the admin and add a Name under 'MYAPP'</h3>
    {% endif %}
    <h3>Add a Name</h3>
    <button>Create</button>
</body>
</html>

That demonstrates the Read in CRUD. Within the myapp directory create a forms.py file. Add the following code:

from django import forms
from myapp.models import Name

class NameForm(forms.ModelForm):
    name_value = forms.CharField(max_length=100, help_text = "Enter a name")

    class Meta:
        model = Name
        fields = ('name_value',)

Update the index.html in the following manner:

<!DOCTYPE html>
<html>
<head>
    <title>myapp</title>
</head>
<body>
    <h2>Simplest Crud Example</h2>
    <p>This shows a list of names and lets you Create, Update and Delete them.</p>
    {% if names_from_context %}
        <ul>
            {% for name in names_from_context %}
                <li>{{ name.name_value }}  <button>Delete</button> <button>Update</button></li>
            {% endfor %}
        </ul>
    {% else %}
        <h3>Please go to the admin and add a Name under 'MYAPP'</h3>
    {% endif %}
    <h3>Add a Name</h3>
    <form id="name_form" method="post" action="/">
        {% csrf_token %}
        {% for field in form.visible_fields %}
            {{ field.errors }}
            {{ field.help_text }}
            {{ field }}
        {% endfor %}
        <input type="submit" name="submit" value="Create">
    </form>
</body>
</html>

Next update the views.py in the following manner:

from django.shortcuts import render, redirect
from myapp.models import Name
from myapp.forms import NameForm

# Create your views here.
def index(request):
    names_from_db = Name.objects.all()

    form = NameForm()

    context_dict = {'names_from_context': names_from_db, 'form': form}

    if request.method == 'POST':
        form = NameForm(request.POST)

        if form.is_valid():
            form.save(commit=True)
            return render(request, 'index.html', context_dict)
        else:
            print(form.errors)    

    return render(request, 'index.html', context_dict)

Restart your server and you should now have a working version of the app with the C in create completed.

TODO add update and delete