Create a Ruby on Rails App in App Service

Azure App Service on Linux provides a highly scalable, self-patching web hosting service using the Linux operating system. This quickstart tutorial shows how to deploy a Ruby on Rails app to App Service on Linux using the Cloud Shell.

Note

The Ruby development stack only supports Ruby on Rails at this time. If you want to use a different platform, such as Sinatra, or if you want to use an unsupported Ruby version, you need to run it in a custom container.

Hello-world

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

Prerequisites

Download the sample

  1. In a terminal window, clone the sample application to your local machine, and navigate to the directory containing the sample code.

    git clone https://github.com/Azure-Samples/ruby-docs-hello-world
    cd ruby-docs-hello-world
    
  2. Make sure the default branch is main.

    git branch -m main
    

    Tip

    The branch name change isn't required by App Service. However, since many repositories are changing their default branch to main, this tutorial also shows you how to deploy a repository from main. For more information, see Change deployment branch.

Run the application locally

  1. Install the required gems. There's a Gemfile included in the sample, so just run the following command:

    bundle install
    
  2. Once the gems are installed, start the app:

    bundle exec rails server
    
  3. Using your web browser, navigate to http://localhost:3000 to test the app locally.

    Hello World configured

Use Azure Cloud Shell

Azure hosts Azure Cloud Shell, an interactive shell environment that you can use through your browser. You can use either Bash or PowerShell with Cloud Shell to work with Azure services. You can use the Cloud Shell preinstalled commands to run the code in this article, without having to install anything on your local environment.

To start Azure Cloud Shell:

Option Example/Link
Select Try It in the upper-right corner of a code block. Selecting Try It doesn't automatically copy the code to Cloud Shell. Screenshot that shows an example of Try It for Azure Cloud Shell.
Go to https://shell.azure.com, or select the Launch Cloud Shell button to open Cloud Shell in your browser. Screenshot that shows how to launch Cloud Shell in a new window.
Select the Cloud Shell button on the menu bar at the upper right in the Azure portal. Screenshot that shows the Cloud Shell button in the Azure portal

To run the code in this article in Azure Cloud Shell:

  1. Start Cloud Shell.

  2. Select the Copy button on a code block to copy the code.

  3. Paste the code into the Cloud Shell session by selecting Ctrl+Shift+V on Windows and Linux, or by selecting Cmd+Shift+V on macOS.

  4. Select Enter to run the code.

Configure a deployment user

FTP and local Git can deploy to an Azure web app by using a deployment user. Once you configure your deployment user, you can use it for all your Azure deployments. Your account-level deployment username and password are different from your Azure subscription credentials.

To configure the deployment user, run the az webapp deployment user set command in Azure Cloud Shell. Replace <username> and <password> with a deployment user username and password.

  • The username must be unique within Azure, and for local Git pushes, must not contain the ‘@’ symbol.
  • The password must be at least eight characters long, with two of the following three elements: letters, numbers, and symbols.
az webapp deployment user set --user-name <username> --password <password>

The JSON output shows the password 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.

Record your username and password to use to deploy your web apps.

Create a resource group

A resource group is a logical container into which Azure resources, such as 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 with the az appservice plan create command.

The following example creates an App Service plan named myAppServicePlan in the Free pricing tier:

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

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

{ 
  "freeOfferExpirationTime": null,
  "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

  1. 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 RUBY|2.6. To see all supported runtimes, run az webapp list-runtimes --os linux.

    az webapp create --resource-group myResourceGroup --plan myAppServicePlan --name <app-name> --runtime 'RUBY|2.6' --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.

  2. Browse to the app 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:

    Splash page

Deploy your application

  1. Since you're deploying the main branch, you need to set the default deployment branch for your App Service app to main (see Change deployment branch). In the Cloud Shell, set the DEPLOYMENT_BRANCH app setting with the az webapp config appsettings set command.

    az webapp config appsettings set --name <app-name> --resource-group myResourceGroup --settings DEPLOYMENT_BRANCH='main'
    
  2. 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>
    
  3. Push to the Azure remote to deploy your app with the following command. When Git Credential Manager prompts you for credentials, make sure 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 main
    

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

   remote: Using turbolinks 5.2.0
   remote: Using uglifier 4.1.20
   remote: Using web-console 3.7.0
   remote: Bundle complete! 18 Gemfile dependencies, 78 gems now installed.
   remote: Bundled gems are installed into `/tmp/bundle`
   remote: Zipping up bundle contents
   remote: .......
   remote: ~/site/repository
   remote: Finished successfully.
   remote: Running post deployment command(s)...
   remote: Deployment successful.
   remote: App container will begin restart within 10 seconds.
   To https://<app-name>.scm.azurewebsites.net/<app-name>.git
      a6e73a2..ae34be9  main -> main
   

Browse to the app

Once the deployment has completed, wait about 10 seconds for the web app to restart, and then navigate to the web app and verify the results.

http://<app-name>.azurewebsites.net

updated web app

Note

While the app is restarting, you may observe the HTTP status code Error 503 Server unavailable in the browser, or the Hey, Ruby developers! default page. It may take a few minutes for the app to fully restart.

Clean up deployment

After the sample script has been run, the following command can be used to remove the resource group and all resources associated with it.

az group delete --name myResourceGroup

Next steps