Create a Python web app in Azure App Service on Linux (Preview)

App Service on Linux provides a highly scalable, self-patching web hosting service using the Linux operating system. This quickstart shows how to deploy a Python app on top of the built-in Python image (Preview) in App Service on Linux using the Azure CLI.

You can follow the steps in this article using a Mac, Windows, or Linux machine.

Sample app running in Azure

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

Prerequisites

To complete this quickstart:

Download the sample

In a terminal window, run the following commands to clone the sample application to your local machine, and navigate to the directory with the sample code.

git clone https://github.com/Azure-Samples/python-docs-hello-world
cd python-docs-hello-world

Run the app locally

Run the application locally so that you see how it should look when you deploy it to Azure. Open a terminal window and use the commands below to install the required dependencies and launch the built-in development server.

# In Bash
python3 -m venv venv
source venv/bin/activate
pip install -r requirements.txt
FLASK_APP=application.py flask run

# In PowerShell
py -3 -m venv env
env\scripts\activate
pip install -r requirements.txt
Set-Item Env:FLASK_APP ".\application.py"
flask run

Open a web browser, and navigate to the sample app at http://localhost:5000/.

You see the Hello World! message from the sample app displayed in the page.

Sample app running locally

In your terminal window, press Ctrl+C to exit the web server.

Open Azure Cloud Shell

Azure Cloud Shell is a free, interactive shell that you can use to run the steps in this article. Common Azure tools are preinstalled and configured in Cloud Shell for you to use with your account. Just select the Copy button to copy the code, paste it in Cloud Shell, and then press Enter to run it. There are a few ways to open Cloud Shell:

Select Try It in the upper-right corner of a code block. Cloud Shell in this article
Open Cloud Shell in your browser. https://shell.azure.com/bash
Select the Cloud Shell button on the menu in the upper-right corner of the Azure portal. Cloud Shell in the portal

Create a deployment user

In the Cloud Shell, create deployment credentials with the az webapp deployment user set command. This deployment user is required for FTP and local Git deployment to a web app. The user name and password are account level. They are different from your Azure subscription credentials.

In the following example, replace <username> and <password> (including brackets) with a new user name and password. The user name must be unique within Azure. The password must be at least eight characters long, with two of the following three elements: letters, numbers, symbols.

az webapp deployment user set --user-name <username> --password <password>

You should get a JSON output, with the password shown as null. If you get a 'Conflict'. Details: 409 error, change the username. If you get a 'Bad Request'. Details: 400 error, use a stronger password.

You create this deployment user only once; you can use it for all your Azure deployments.

Note

Record the user name and password. You need them to deploy the web app later.

Create a resource group

A resource group is a logical container into which Azure resources like web apps, databases, and storage accounts are deployed and managed. For example, you can choose to delete the entire resource group in one simple step later.

In the Cloud Shell, create a resource group with the az group create command. The following example creates a resource group named myResourceGroup in the West Europe location. To see all supported locations for App Service on Linux in Basic tier, run the az appservice list-locations --sku B1 --linux-workers-enabled command.

az group create --name myResourceGroup --location "West Europe"

You generally create your resource group and the resources in a region near you.

When the command finishes, a JSON output shows you the resource group properties.

Create an Azure App Service plan

In the Cloud Shell, create an App Service plan in the resource group with the az appservice plan create command.

The following example creates an App Service plan named myAppServicePlan in the Basic pricing tier (--sku B1) and in a Linux container (--is-linux).

az appservice plan create --name myAppServicePlan --resource-group myResourceGroup --sku B1 --is-linux

When the App Service plan has been created, the Azure CLI shows information similar to the following example:

{ 
  "adminSiteName": null,
  "appServicePlanName": "myAppServicePlan",
  "geoRegion": "West Europe",
  "hostingEnvironmentProfile": null,
  "id": "/subscriptions/0000-0000/resourceGroups/myResourceGroup/providers/Microsoft.Web/serverfarms/myAppServicePlan",
  "kind": "linux",
  "location": "West Europe",
  "maximumNumberOfWorkers": 1,
  "name": "myAppServicePlan",
  < JSON data removed for brevity. >
  "targetWorkerSizeId": 0,
  "type": "Microsoft.Web/serverfarms",
  "workerTierName": null
} 

Create a web app

Create a web app in the myAppServicePlan App Service plan.

In the Cloud Shell, you can use the az webapp create command. In the following example, replace <app_name> with a globally unique app name (valid characters are a-z, 0-9, and -). The runtime is set to PYTHON|3.7. To see all supported runtimes, run az webapp list-runtimes --linux.

# Bash
az webapp create --resource-group myResourceGroup --plan myAppServicePlan --name <app_name> --runtime "PYTHON|3.7" --deployment-local-git
# PowerShell
az --% webapp create --resource-group myResourceGroup --plan myAppServicePlan --name <app_name> --runtime "PYTHON|3.7" --deployment-local-git

When the web app has been created, the Azure CLI shows output similar to the following example:

Local git is configured with url of 'https://<username>@<app_name>.scm.azurewebsites.net/<app_name>.git'
{
  "availabilityState": "Normal",
  "clientAffinityEnabled": true,
  "clientCertEnabled": false,
  "cloningInfo": null,
  "containerSize": 0,
  "dailyMemoryTimeQuota": 0,
  "defaultHostName": "<app_name>.azurewebsites.net",
  "deploymentLocalGitUrl": "https://<username>@<app_name>.scm.azurewebsites.net/<app_name>.git",
  "enabled": true,
  < JSON data removed for brevity. >
}

You’ve created an empty new web app, with git deployment enabled.

Note

The URL of the Git remote is shown in the deploymentLocalGitUrl property, with the format https://<username>@<app_name>.scm.azurewebsites.net/<app_name>.git. Save this URL as you need it later.

Browse to the site to see your newly created web app with built-in image. Replace <app name> with your web app name.

http://<app_name>.azurewebsites.net

Here is what your new web app should look like:

Empty web app page

Push to Azure from Git

Back in the local terminal window, add an Azure remote to your local Git repository. Replace <deploymentLocalGitUrl-from-create-step> with the URL of the Git remote that you saved from Create a web app.

git remote add azure <deploymentLocalGitUrl-from-create-step>

Push to the Azure remote to deploy your app with the following command. When prompted for credentials by Git Credential Manager, make sure that you enter the credentials you created in Configure a deployment user, not the credentials you use to sign in to the Azure portal.

git push azure master

This command may take a few minutes to run. While running, it displays information similar to the following example:

Counting objects: 42, done.
Delta compression using up to 8 threads.
Compressing objects: 100% (39/39), done.
Writing objects: 100% (42/42), 9.43 KiB | 0 bytes/s, done.
Total 42 (delta 15), reused 0 (delta 0)
remote: Updating branch 'master'.
remote: Updating submodules.
remote: Preparing deployment for commit id 'c40efbb40e'.
remote: Generating deployment script.
remote: Generating deployment script for python Web Site
.
.
.
remote: Finished successfully.
remote: Running post deployment command(s)...
remote: Deployment successful.
remote: App container will begin restart within 10 seconds.
To https://user2234@cephalin-python.scm.azurewebsites.net/cephalin-python.git
 * [new branch]      master -> master

Browse to the app

Browse to the deployed application using your web browser.

http://<app_name>.azurewebsites.net

The Python sample code is running in a web app with built-in image.

Sample app running in Azure

Congratulations! You've deployed your first Python app to App Service on Linux.

Update locally and redeploy the code

In the local repository, open the application.py file, and make a small change to the text in the last line:

return "Hello Azure!"

Commit your changes in Git, and then push the code changes to Azure.

git commit -am "updated output"
git push azure master

Once deployment has completed, switch back to the browser window that opened in the Browse to the app step, and refresh the page.

Updated sample app running in Azure

Manage your new Azure web app

Go to the Azure portal to manage the web app you created.

From the left menu, click App Services, and then click the name of your Azure web app.

Portal navigation to Azure web app

You see your web app's Overview page. Here, you can perform basic management tasks like browse, stop, start, restart, and delete.

App Service page in Azure portal

The left menu provides different pages for configuring your app.

Clean up resources

In the preceding steps, you created Azure resources in a resource group. If you don't expect to need these resources in the future, delete the resource group by running the following command in the Cloud Shell:

az group delete --name myResourceGroup

This command may take a minute to run.

Next steps

The built-in Python image in App Service on Linux is currently in Preview. You can create production Python apps using a custom container instead.