Python Django 2021 Bootcamp Course Sessions

Course Content

Session #1: Views, URLs & Templates
Session #2: Admin Panel, Models & Database Queries
Session #3: Models Forms & CRUD
Session #4: Static Files & Theme Installation

Views, URLs & Templates

Start new project

django-admin startproject devsearchlive .

The previous command will generate automatically all files needed for your project as listed bellow.

 ├── devsearchlive
 │   ├── asgi.py
 │   ├── __init__.py
 │   ├── settings.py
 │   ├── urls.py
 │   └── wsgi.py
 ├── manage.py
 ├── README.md
 └── requirements.txt

Run the server

Once the project created, you can start running the server anytime you would like by running the following command:
```
python manage.py runserver
```

Create new application

The following command will create a new projects application within the main devsearchlive directory

python manage.py startapp projects

The new generated files therefore are:

 projects
 ├── admin.py
 ├── apps.py
 ├── __init__.py
 ├── migrations
 │   └── __init__.py
 ├── models.py
 ├── tests.py
 └── views.py

Go to the settings.py file within the devsearchlive directory and add the name of the created application as shown bellow

 # Application definition

 INSTALLED_APPS = [
     "django.contrib.admin",
     "django.contrib.auth",
     "django.contrib.contenttypes",
     "django.contrib.sessions",
     "django.contrib.messages",
     "django.contrib.staticfiles",

     "projects.apps.ProjectsConfig",
 ]

Add new projects/ url

Once the application created, we can add now a new url to access that application. We need therefore, to crate a new project function (later we will be using views instead) and create new path to that function.

We need to modify the urls.py file within the devsearchlive directory as following:
```
from django.http import HttpResponse

def projects(request):
    return HttpResponse("This is the projects page!")

urlpatterns = [
    path("admin/", admin.site.urls),
    path("projects/", projects),
]
```

Render dynamic pages

It's also possible to render dynamic pages by using <int:pk> configuration in the url paths.

Bellow an example using a simple function within the url.py file.

from django.http import HttpResponse

def project(request, pk):
    return HttpResponse(f"This is the project No. {str(pk)} page!")

urlpatterns = [
    path("admin/", admin.site.urls),
    path("projects/", projects),
    path("project/<str:pk>/", project),
]

Add a urls.py for each application

The correct way of adding paths and views is to use a urls.py and views.py of each application.

To do so, let move the projects and project functions to the views.py file inside the projects application

We create than a urls.py

   from django.urls import path

   from . import views

   urlpatterns = [
       path("", views.projects),
       path("project/<str:pk>/", views.project),
   ]

Include the projects application urls.py into the main devsearchlive directory urls.py file

from django.contrib import admin
from django.urls import path, include

urlpatterns = [
    path("admin/", admin.site.urls),
    path("", include("projects.urls"))
]

Templates and Template Inheritance

One possible configuration is inside the root directory, we add templates directory

    .
    ├── assets
    ├── devsearchlive
    │   └── __pycache__
    ├── projects
    │   ├── migrations
    │   │   └── __pycache__
    │   └── __pycache__
    └── templates

Once the templates are used, we will be no longer using the HttpResponse in views but the render

 def projects(request):
     return render(request, "projects.html")

However, before using the templates we need to tell Django where they are located, so we have to update the settings.py file

 import os

 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",
             ],
         },
     },
 ]

Another way to use templates is for each application, we add a specific templates directory. This is the Django recommended method

 .
 ├── assets
 ├── devsearchlive
 │   └── __pycache__
 ├── projects
 │   ├── migrations
 │   │   └── __pycache__
 │   ├── __pycache__
 │   └── templates
 │       └── projects
 └── templates

In this case the view function will be modified by specifying the name of the application inside the render method

 def projects(request):
     return render(request, "projects/projects.html")

Admin Panel, Models & Database Queries

The aim here is to build the DB, manage interactions and design queries.

Use the default SQLite database, before creating models or using the Admin panel we need to migrate all changes
```
python manage.py makemigrations
python manage.py migrate
```
Create superuser account for the administration of the application
```
python manage.py createsuperuser
```
We can now access the admin panel using the chosen username and password

Now if you access successfully to the Django Admin interface you'll see the following dashboard

Create our own Models by adding our DB tables to the models.py within the application directory

 from django.db import models
 import uuid

 class Project(models.Model):
     # owner = WILL BE COMPLETED LATER
     title = models.CharField(max_length=200)
     description = models.TextField(null=True, blank=True)
     # feature_image = WILL BE COMPLETED LATER
     demo_link = models.CharField(max_length=1000, null=True, blank=True)
     source_link = models.CharField(max_length=1000, null=True, blank=True)
     vote_total = models.IntegerField(default=0)
     vote_ratio = models.IntegerField(default=0)
     created = models.DateTimeField(auto_now_add=True)
     id = models.UUIDField(default=uuid.uuid4, unique=True, primary_key=True, editable=False)

     def __str__(self):
         return self.title

Make new migration to update the DB with the new model just created
```
python manage.py makemigrations
python manage.py migrate
```
Register the model within the admin panel to be visible in the admin interface, therefore, we need to update the admin.py file of the application as following
```
from django.contrib import admin

# Register your models here.
from .models import Project

admin.site.register(Project)
```
Now we can see our Model inside the Admin panel
Now models can be used within the view.py file

Models Forms & CRUD (Create Read Update Delete)

Two ways are possible under django to deal with CRUD (i) function based views or (ii) class based views. The class based views is the easiest way, however, here we will be using the function based view to see the complete flow of the views.

Model Forms

We start by creating form.py file inside the projects directory

from django.forms import ModelForm
from .models import Project

class ProjectForm(ModelForm):
    class Meta:
        model = Project
        fields = "__all__"

We can import now the created form inside the views.py
```
from .forms import ProjectForm
```

The next step is to render the created model. We start by adding a create project on the navbar

<h1>Logo</h1>

<a href="/">Home</a>
<a href="{% url 'create-project' %}">Add Project</a>

<hr />

Then, we create a new function view under the views.py

def createProject(request):
    form = ProjectForm()
    context = {"form": form}
    exclude = ["vote_total", "vote_ratio"]

    return render(request, "projects/project-form.html", context)

Next step consists of creating the project-form.html template

{% extends "main.html" %} {% block content %}

<h2>Create new project:</h2>

<form method="POST" action="">
  {% csrf_token %} {{form.as_p}}
  <input type="submit" value="Submit" />
</form>

{% endblock content %}

Finally, we need to update the urls.py file inside the projects directory

from django.urls import path

from . import views

urlpatterns = [
    path("", views.projects, name="projects"),
    path("project/<str:pk>/", views.project, name="project"),
    path("create-project/", views.createProject, name="create-project"),
]

CRUD Functionalities

Create - Under view.py we have to add the following code within the createProject method. The redirect was also imported for this method

def createProject(request):
   form = ProjectForm()

   if request.method == "POST":
      form = ProjectForm(request.POST)

      if form.is_valid():
            form.save()
            return redirect("projects")

   context = {"form": form}

   return render(request, "projects/project-form.html", context)

Update - We will create new method updateProject within the views.py file which is similar to the createProject

def updateProject(request, pk):
   project = Project.objects.get(id=pk)

   form = ProjectForm(instance=project)

   if request.method == "POST":
      form = ProjectForm(request.POST, instance=project)

      if form.is_valid():
            form.save()
            return redirect("projects")

   context = {"form": form}
   return render(request, "projects/project-form.html", context)

We need to update the urls.py too

from django.urls import path

from . import views

urlpatterns = [
   path("", views.projects, name="projects"),
   path("project/<str:pk>/", views.project, name="project"),
   path("create-project/", views.createProject, name="create-project"),
   path("update-project/<str:pk>/", views.updateProject, name="update-project"),
]

Delete - We start by creating a validation template delete.html

{% extends "main.html" %} {% block content %}

<h2>Delete {{ object }}:</h2>

<form action="" method="POST">
  {% csrf_token %}

  <p>Are you sure you want to delete {{object}}?</p>
  <a href="{% url 'projects' %}">Go Back!</a>
  <input type="submit" value="Delete" />
</form>

{% endblock content %}

Then we create the deleteProject method inside the views.py file

def deleteProject(request, pk):
   project = Project.objects.get(id=pk)

   if request.method == "POST":
      project.delete()
      return redirect("projects")

   return render(request, "projects/delete.html", {"object":project})

We need to update the urls.py too

from django.urls import path

from . import views

urlpatterns = [
   path("", views.projects, name="projects"),
   path("project/<str:pk>/", views.project, name="project"),
   path("create-project/", views.createProject, name="create-project"),
   path("update-project/<str:pk>/", views.updateProject, name="update-project"),
   path("delete-project/<str:pk>/", views.deleteProject, name="delete-project"),
]

Static Files & Theme Installation

The way we will be using static files here, is by keeping them ona separate static directory within the root folder.

Create a static directory inside the project root folder

.
├── assets
├── devsearchlive
│   └── __pycache__
├── projects
│   ├── migrations
│   │   └── __pycache__
│   ├── __pycache__
│   └── templates
│       └── projects
├── static
└── templates

Connect the static files/folders with the main settings.py file by adding the following commands

STATICFILES_DIRS = [
   # BASE_DIR / "static"
   os.path.join(BASE_DIR, "static"),
]

We need to load the static files inside the main template

<!DOCTYPE html>
<html lang="en">
  {% load static %}

  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Dev. Search Live</title>

    <link
      rel="stylesheet"
      type="text/css"
      href="{% static 'styles/main.css' %}"
    />
  </head>

  <body>
    {% include "navbar.html" %} {% block content %} {% endblock content %}
  </body>
</html>

Now, we can update our model to be able using the profiles pictures

class Project(models.Model):
   # owner =
   title = models.CharField(max_length=200)
   description = models.TextField(null=True, blank=True)
   feature_image = models.ImageField(null=True, blank=True, default="default.jpg")
   demo_link = models.CharField(max_length=1000, null=True, blank=True)
   source_link = models.CharField(max_length=1000, null=True, blank=True)
   vote_total = models.IntegerField(default=0)
   vote_ratio = models.IntegerField(default=0)
   tags = models.ManyToManyField("Tag", blank=True)
   created = models.DateTimeField(auto_now_add=True)
   id = models.UUIDField(default=uuid.uuid4, unique=True, primary_key=True, editable=False)

   def __str__(self):
      return self.title

To avoid Django uploading images within the root directory, we can change the media settings, and we need to add a MEDIA_URL too
```
MEDIA_URL = "/images/"
MEDIA_ROOT = os.path.join(BASE_DIR, "static/images")
```

We can update the main urls.py as following

from django.conf import settings
from django.conf.urls.static import static

urlpatterns += static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)

The images are accessible now via the html templates, for a single project, we can modify the project.html as shown bellow:
```
<img
  style="max-width: 500px;"
  src="{{project.feature_image.url}}"
  alt="Project image"
/>
```

The following modifications are needed to be able uploading images using our form instead of the admin dashboard

The project-form.html file will be updated as following:

{% extends "main.html" %} {% block content %}

<h2>Create new project:</h2>

<form method="POST" action="" enctype="multipart/form-data">
  {% csrf_token %} {{form.as_p}}
  <input type="submit" value="Submit" />
</form>

{% endblock content %}

The views.py also will be updated

def createProject(request):
   form = ProjectForm()

   if request.method == "POST":
      form = ProjectForm(request.POST, request.FILES)

      if form.is_valid():
            form.save()
            return redirect("projects")

   context = {"form": form}

   return render(request, "projects/project-form.html", context)

def updateProject(request, pk):
   project = Project.objects.get(id=pk)

   form = ProjectForm(instance=project)

   if request.method == "POST":
      form = ProjectForm(request.POST, request.FILES, instance=project)

      if form.is_valid():
            form.save()
            return redirect("projects")

   context = {"form": form}
   return render(request, "projects/project-form.html", context)

Requirements

- Django==4.1.6
- Pillow==9.4.0

malek2610/Django-Bootcamp