Merge pull request #578 from diegorusso/python-django

Create Django learning path

content/learning-paths/servers-and-cloud-computing/django/_index.md

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+---
+title: Learn how to deploy a Django application
+
+minutes_to_complete: 30
+
+who_is_this_for: This is an introductory topic for engineers who want to deploy a Django based application on Arm machines.
+
+learning_objectives:
+    - Create a simple Django application
+    - Deploy the Django application using Nginx and PostgreSQL
+    - Verify that the Django application is working correctly
+
+prerequisites:
+    - At least either an [Arm based instance](../csp/) from a cloud service provider, on-premises Arm server, or a Linux virtual machine on your Arm device.
+    - sudo access to install dependencies and to modify system configuration files.
+    - Be comfortable with SSH/Linux terminal and basic system administration tasks.
+    - To install both [Nginx](../nginx/) and [PostgreSQL](../postgresql/)
+
+author_primary: Diego Russo
+
+### Tags
+skilllevels: Introductory
+subjects: Web
+armips:
+    - Neoverse
+tools_software_languages:
+    - Django
+    - Python
+    - Nginx
+    - PostgreSQL
+operatingsystems:
+    - Linux
+
+
+### FIXED, DO NOT MODIFY
+# ================================================================================
+weight: 1                       # _index.md always has weight of 1 to order correctly
+layout: "learningpathall"       # All files under learning paths have this same wrapper
+learning_path_main_page: "yes"  # This should be surfaced when looking for related content. Only set for _index.md of learning path content.
+---

content/learning-paths/servers-and-cloud-computing/django/_next-steps.md

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+---
+next_step_guidance: Thank you for learning how to deploy a Django application on Arm machines.
+
+recommended_path: /learning-paths/servers-and-cloud-computing/memcached_cache/ 
+
+further_reading:
+    - resource:
+        title: PostgreSQL Documentation
+        link: https://www.postgresql.org/docs/
+        type: documentation
+    - resource:
+        title: Nginx Documentation
+        link: https://nginx.org/en/docs/
+        type: documentation
+    - resource:
+        title: Django Documentation
+        link: https://docs.djangoproject.com/
+        type: documentation
+
+
+# ================================================================================
+#       FIXED, DO NOT MODIFY
+# ================================================================================
+weight: 21                  # set to always be larger than the content in this path, and one more than 'review'
+title: "Next Steps"         # Always the same
+layout: "learningpathall"   # All files under learning paths have this same wrapper
+---

content/learning-paths/servers-and-cloud-computing/django/_review.md

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+---
+review:
+    - questions:
+        question: >
+            Does Django run on Arm servers?
+        answers:
+            - "Yes"
+            - "No"
+        correct_answer: 1
+        explanation: >
+            Django is a pure Python application so it is fully supported on 64-bit Arm servers running Linux.
+
+    - questions:
+        question: >
+            Do you need to perform Arm specific steps during the learning path?
+        answers:
+            - "Yes"
+            - "No"
+        correct_answer: 2
+        explanation: >
+            The learning path doesn't contains steps specific for Arm as all the software stack used is fully supporte on 64-bit Arm servers running Linux.
+
+
+# ================================================================================
+#       FIXED, DO NOT MODIFY
+# ================================================================================
+title: "Review"                 # Always the same title
+weight: 20                      # Set to always be larger than the content in this path
+layout: "learningpathall"       # All files under learning paths have this same wrapper
+---

content/learning-paths/servers-and-cloud-computing/django/create_django_application.md

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+---
+title: Create the Django application
+weight: 3
+
+### FIXED, DO NOT MODIFY
+layout: learningpathall
+---
+
+## Create the Django project
+
+From the terminal where the virtual environment is activated, you need to
+create a Django project
+
+```bash
+django-admin startproject myproject
+```
+
+The above command creates a directory called `myproject` that contains the basic
+structure of a Django application. Inspect the project files:
+
+```bash
+tree myproject/
+```
+The output should look like:
+
+```output
+myproject/
+    manage.py
+    myproject
+        asgi.py
+        __init__.py
+        settings.py
+        urls.py
+        wsgi.py
+
+```
+
+Feel free to explore the content of these files.
+
+Now you can test the application by starting the development server.
+
+```bash
+cd myproject
+python manage.py runserver 0.0.0.0:8000
+```
+You will see messages similar to:
+
+```output
+Watching for file changes with StatReloader
+Performing system checks...
+
+System check identified no issues (0 silenced).
+
+You have 18 unapplied migration(s). Your project may not work properly until
+you apply the migrations for app(s): admin, auth, contenttypes, sessions.
+Run 'python manage.py migrate' to apply them.
+November 06, 2023 - 22:34:05
+Django version 4.2.7, using settings 'myproject.settings'
+Starting development server at http://0.0.0.0:8000/
+Quit the server with CONTROL-C.
+```
+
+{{% notice Note %}}
+In the above command you speficied 0.0.0.0:8000. This means
+that the web server is listening to all available ports. You need to specify
+this value if you developing on a remote machine because by default the
+development server listens only on localhost
+{{% /notice %}}
+
+Now open a web browser and point it to the IP address of your machine followed
+by `:8000`. You should see something like that:
+
+![alt-text #center](django-install.png "Successful installation of a Django project")
+
+## Create the Django application
+Now that you have a Django project, it's now time to create a Django
+application within the project. Type:
+
+```bash
+python manage.py startapp aarch64app
+tree aarch64app
+```
+
+The output should look similar to:
+
+```output
+aarch64app/
+    admin.py
+    apps.py
+    __init__.py
+    migrations
+        __init__.py
+    models.py
+    tests.py
+    views.py
+```
+
+Again, feel free to explore the content of these files.
+
+It's now time to write some code that will be executed by the Django
+application.
+With your favourite editor, open `aarch64app/views.py` and replace the content
+with the following:
+
+```python
+import platform
+
+from django.http import HttpResponse
+
+# Create your views here.
+def index(request):
+    return HttpResponse(f"Hello world from an {platform.machine()} machine.") 
+```
+
+Next you need to map a URL to this view. Create a new file `aarch64app/urls.py`
+with the following content:
+
+```python
+from django.urls import path
+
+from . import views
+
+urlpatterns = [
+    path("", views.index, name="index"),
+]
+```
+
+Now you need to make it visible at the project level. Edit `myproject/urls.py`
+and add the following code
+
+```python
+from django.contrib import admin
+from django.urls import include, path
+
+urlpatterns = [
+    path("aarch64app/", include("aarch64app.urls")),
+    path('admin/', admin.site.urls),
+]
+```
+
+You have now connected the index view with the URL `/aarch64app`. Run the
+development web server again with:
+
+```bash
+python manage.py runserver 0.0.0.0:8000
+```
+
+Open http://your_IP:8000/aarch64app/ with
+your browser. You should see the hello world message.
+
+
+![alt-text #center](django-app.png "Successful call to a Django view")