Tutorial on how to Deploy Django app with App Service and Azure Database for PostgreSQL - Flexible Server in virtual network (2023)

APPLIES TO: Azure Database for PostgreSQL - Flexible Server

In this tutorial you'll learn how to deploy a Django application in Azure using App Services and Azure Database for PostgreSQL - Flexible Server in a virtual network.

Prerequisites

If you don't have an Azure subscription, create a free account before you begin.

This article requires that you're running the Azure CLI version 2.0 or later locally. To see the version installed, run the az --version command. If you need to install or upgrade, see Install Azure CLI.

You'll need to log in to your account using the az login command. Note the id property from the command output for the corresponding subscription name.

az login

If you have multiple subscriptions, choose the appropriate subscription in which the resource should be billed. Select the specific subscription ID under your account using az account set command. Substitute the subscription ID property from the az login output for your subscription into the subscription ID placeholder.

az account set --subscription <subscription id>

Clone or download the sample app

git clone https://github.com/Azure-Samples/djangoapp

cd djangoapp

The djangoapp sample contains the data-driven Django polls app you get by following Writing your first Django app in the Django documentation. The completed app is provided here for your convenience.

The sample is also modified to run in a production environment like App Service:

• Production settings are in the azuresite/production.py file. Development details are in azuresite/settings.py.
• The app uses production settings when the DJANGO_ENV environment variable is set to "production". You create this environment variable later in the tutorial along with others used for the PostgreSQL database configuration.

These changes are specific to configuring Django to run in any production environment and aren't particular to App Service. For more information, see the Django deployment checklist.

Create a PostgreSQL Flexible Server in a new virtual network

Create a private flexible server and a database inside a virtual network (VNET) using the following command:

# Create Flexible server in a VNETaz postgres flexible-server create --resource-group myresourcegroup --location westus2

This command performs the following actions, which may take a few minutes:

• Create the resource group if it doesn't already exist.
• Generates a server name if it isn't provided.
• Create a new virtual network for your new postgreSQL server. Make a note of virtual network name and subnet name created for your server since you need to add the web app to the same virtual network.
• Creates admin username, password for your server if not provided. Make a note of the username and password to use in the next step.
• Create a database postgres that can be used for development. You can run psql to connect to the database to create a different database.

Deploy the code to Azure App Service

In this section, you create app host in App Service app, connect this app to the Postgres database, then deploy your code to that host.

Create the App Service web app in a virtual network

In the terminal, make sure you're in the repository root (djangoapp) that contains the app code.

Create an App Service app (the host process) with the az webapp up command:

# Create a web appaz webapp up --resource-group myresourcegroup --location westus2 --plan DjangoPostgres-tutorial-plan --sku B1 --name <app-name># Enable VNET integration for web app.# Replace <vnet-name> and <subnet-name> with the virtual network and subnet name that the flexible server is using.az webapp vnet-integration add -g myresourcegroup -n mywebapp --vnet <vnet-name> --subnet <subnet-name># Configure database information as environment variables# Use the postgres server name , database name , username , password for the database created in the previous stepsaz webapp config appsettings set --settings DJANGO_ENV="production" DBHOST="<postgres-server-name>.postgres.database.azure.com" DBNAME="postgres" DBUSER="<username>" DBPASS="<password>"

• For the --location argument, use the same location as you did for the database in the previous section.
• Replace <app-name> with a unique name across all Azure (the server endpoint is https://\<app-name>.azurewebsites.net). Allowed characters for <app-name> are A-Z, 0-9, and -. A good pattern is to use a combination of your company name and an app identifier.
• Create the App Service plan DjangoPostgres-tutorial-plan in the Basic pricing tier (B1), if it doesn't exist. --plan and --sku are optional.
• Create the App Service app if it doesn't exist.
• Enable default logging for the app, if not already enabled.
• Upload the repository using ZIP deployment with build automation enabled.
• az webapp vnet-integration command adds the web app in the same virtual network as the postgres server.
• The app code expects to find database information in many environment variables. To set environment variables in App Service, you create "app settings" with the az webapp config appsettings set command.

Run Django database migrations

Django database migrations ensure that the schema in the PostgreSQL on Azure database match those described in your code.

1. Open an SSH session in the browser by navigating to https://<app-name>.scm.azurewebsites.net/webssh/host and sign in with your Azure account credentials (not the database server credentials).

2. In the SSH session, run the following commands (you can paste commands using Ctrl+Shift+V):

   (Video) How to deploy PostgreSQL on Azure

   cd site/wwwroot# Activate default virtual environment in App Service containersource /antenv/bin/activate# Install packagespip install -r requirements.txt# Run database migrationspython manage.py migrate# Create the super user (follow prompts)python manage.py createsuperuser

3. The createsuperuser command prompts you for superuser credentials. For the purposes of this tutorial, use the default username root, press Enter for the email address to leave it blank, and enter postgres1 for the password.

Create a poll question in the app

4. In a browser, open the URL http://<app-name>.azurewebsites.net. The app should display the message "No polls are available" because there are no specific polls yet in the database.

5. Browse to http://<app-name>.azurewebsites.net/admin. Sign in using superuser credentials from the previous section (root and postgres1). Under Polls, select Add next to Questions and create a poll question with some choices.

6. Browse again to http://<app-name>.azurewebsites.net/ to confirm that the questions are now presented to the user. Answer questions however you like to generate some data in the database.

Congratulations! You're running a Python Django web app in Azure App Service for Linux, with an active Postgres database.

Make code changes and redeploy

In this section, you make local changes to the app and redeploy the code to App Service. In the process, you set up a Python virtual environment that supports ongoing work.

Run the app locally

In a terminal window, run the following commands. Be sure to follow the prompts when creating the superuser:

# Configure the Python virtual environmentpython3 -m venv venvsource venv/bin/activate# Install packagespip install -r requirements.txt# Run Django migrationspython manage.py migrate# Create Django superuser (follow prompts)python manage.py createsuperuser# Run the dev serverpython manage.py runserver

Once the web app is fully loaded, the Django development server provides the local app URL in the message, "Starting development server at http://127.0.0.1:8000/. Quit the server with CTRL-BREAK".

Test the app locally with the following steps:

1. Go to http://localhost:8000 in a browser, which should display the message "No polls are available".

   (Video) Introducing Flexible Server in Azure Database for PostgreSQL & MySQL | Azure Friday

2. Go to http://localhost:8000/admin and sign in using the admin user you created previously. Under Polls, again select Add next to Questions and create a poll question with some choices.

3. Go to http://localhost:8000 again and answer the question to test the app.

4. Stop the Django server by pressing Ctrl+C.

When running locally, the app is using a local Sqlite3 database and doesn't interfere with your production database. You can also use a local PostgreSQL database, if desired, to better simulate your production environment.

Update the app

In polls/models.py, locate the line that begins with choice_text and change the max_length parameter to 100:

# Find this lie of code and set max_length to 100 instead of 200choice_text = models.CharField(max_length=100)

Because you changed the data model, create a new Django migration and migrate the database:

python manage.py makemigrationspython manage.py migrate

Run the development server again with python manage.py runserver and test the app at to http://localhost:8000/admin:

Stop the Django web server again with Ctrl+C.

Redeploy the code to Azure

Run the following command in the repository root:

az webapp up

This command uses the parameters cached in the .azure/config file. Because App Service detects that the app already exists, it just redeploys the code.

Rerun migrations in Azure

Because you made changes to the data model, you need to rerun database migrations in App Service.

Open an SSH session again in the browser by navigating to https://<app-name>.scm.azurewebsites.net/webssh/host. Then run the following commands:

cd site/wwwroot# Activate default virtual environment in App Service containersource /antenv/bin/activate# Run database migrationspython manage.py migrate

Review app in production

Browse to http://<app-name>.azurewebsites.net and test the app again in production. (Because you only changed the length of a database field, the change is only noticeable if you try to enter a longer response when creation a question.)

Manage your app in the Azure portal

In the Azure portal, search for the app name and select the app in the results.

By default, the portal shows your app's Overview page, which provides a general performance view. Here, you can also perform basic management tasks like browse, stop, restart, and delete. The tabs on the left side of the page show the different configuration pages you can open.

Clean up resources

If you'd like to keep the app or continue to the next tutorial, skip ahead to Next steps. Otherwise, to avoid incurring ongoing charges you can delete the resource group create for this tutorial:

az group delete -g myresourcegroup

The command uses the resource group name cached in the .azure/config file. By deleting the resource group, you also deallocate and delete all the resources contained within it.

Next steps

Learn how to map a custom DNS name to your app:

Learn how App Service runs a Python app: