Get started developing Ruby on Rails apps that run on App Engine flexible environment . The apps you create run on the same infrastructure that powers all of Google's products, so you can be confident that they can scale to serve all of your users, whether there are a few or millions of them.
This tutorial assumes you are familiar with Rails web development. It walks you through deploying a new Rails app.
This tutorial supports and requires Ruby 3.0 or later.
Before you begin
- Sign in to your Google Cloud account. If you're new to Google Cloud, create an account to evaluate how our products perform in real-world scenarios. New customers also get $300 in free credits to run, test, and deploy workloads.
-
In the Google Cloud console, on the project selector page, select or create a Google Cloud project.
-
Make sure that billing is enabled for your Google Cloud project .
-
In the Google Cloud console, on the project selector page, select or create a Google Cloud project.
-
Make sure that billing is enabled for your Google Cloud project .
- Install the Google Cloud CLI.
-
To initialize the gcloud CLI, run the following command:
gcloud init
Set up your local environment for Rails
To set up your local environment for Rails development, you'll need to:
Alternatively, you can use Cloud Shell , which comes with Ruby, Rails, and the Google Cloud CLI already installed.
For additional information on installing Rails and its dependencies, see the official Getting started with Rails guide.
After you complete the prerequisites, you can create and deploy a Rails app. The following sections guide you through configuring, running, and deploying an app.
Create a new app
-
Create a new Rails sample app.
rails new appengine_example
-
Go to the directory that contains the sample code.
cd appengine_example
Run the app locally
To run the new Rails app on your local computer:
-
Start a local web server.
bundle exec rails server
-
In your browser, go to http://localhost:3000/ .
The sample app displays the Rails logo with the Rails and Ruby versions.
Add a simple page
Now add a Welcome page to the generated Rails app.
-
To generate the scaffolding for a new page, create a new Rails controller named
WelcomeController
with anindex
action.bundle exec rails generate controller Welcome index
-
Open the file
app/views/welcome/index.html.erb
to see the following boilerplate HTML. -
Modify the file however you like. For example, you can use the following content:
-
Set the
index
controller action as the root action for Rails. Then, whenever a user visits the Rails app, they see your welcome page. -
Open the file
config/routes.rb
to see the following generated content. -
To modify this file, add
root 'welcome#index'
. -
Save the file and close it. Test the Rails app as you did before.
Deploy the app to App Engine flexible environment
App Engine flexible environment uses a file called app.yaml
.
to describe an app's deployment configuration. If this file isn't present, the
gcloud CLI tries to guess the deployment configuration. However,
it is a good idea to provide this file because Rails requires a secret key in a
production environment.
To configure the sample app for deployment to App Engine, create a new
file named app.yaml
at the root of your sample app directory and add the
following:
Configure the Rails secret key
When you deploy a Rails app in the production environment, set the environment
variable SECRET_KEY_BASE
to a secret key that is used to protect
user session data. This environment variable is read in the config/secrets.yml
file.
-
Generate a new secret key.
bundle exec rails secret
-
Copy the generated secret key. You use the secret key in the next step.
-
Open the file
app.yaml
that you created earlier, and add anenv_variables
section. Theenv_variables
sets environment variables in theproduction
environment in App Engine flexible environment. Yourapp.yaml
should look like the example below, with[SECRET_KEY]
replaced with your copied secret key.
Set up an App Engine flexible environment app
If this is the first time you are deploying an app, you need to create an App Engine flexible environment app to help you select the region in which to run the Rails app. You can read more about regions and zones .
-
Create an App Engine app. By default, the following command creates two instances:
gcloud app create
-
Select a region that supports the App Engine flexible environment for Ruby apps.
Deploy to App Engine flexible environment
Deploy the sample app by running the following command:
gcloud app deploy
Wait for the message that notifies you that the update has completed. This can take several minutes.
Access the deployed Rails app
-
To retrieve your project ID, run
gcloud info
. -
In your browser, enter the following URL:
https:// PROJECT_ID . REGION_ID .r.appspot.com
Replace the following:
-
PROJECT_ID
: Your Google Cloud project ID -
REGION_ID
: A code that App Engine assigns to your app
-
The following content is displayed.
This time, your request is served by the Rails app running in App Engine flexible environment.
This command deploys the app as described in app.yaml
and sets the newly
deployed version as the default version, causing it to serve all new traffic.
As the app deploys, you might see several repeated messages while the
platform checks whether the app is serving. This is normal. Wait for the
message that notifies you that the update of the app is complete.
If you update your app, you can deploy the updated version by entering the same command you used to deploy the app the first time. The new deployment creates a new version of your app and promotes it to the default version. The older versions of your app remain, as do their associated VM instances. Be aware that all of these app versions and VM instances are billable resources.
Read App Engine logs
Now that you have deployed your Rails app, you may want to read the logs. You
can read the app logs by using the Logs Explorer
located in the Google Cloud console, or by using gcloud app logs read
.
You can learn more about reading logs by using the gcloud CLI
.
Clean up resources
After you finish the tutorial, you can clean up the resources that you created so that they stop using quota and incurring charges. The following sections describe how to delete or turn off these resources.
Delete project
The easiest way to eliminate billing is to delete the project that you created for the tutorial.
To delete the project:
- In the Google Cloud console, go to the Manage resources page.
- In the project list, select the project that you want to delete, and then click Delete .
- In the dialog, type the project ID, and then click Shut down to delete the project.
Delete an App Engine version
To delete an app version:
- In the Google Cloud console, go to the Versions page for App Engine.
- Select the checkbox for the non-default app version that you want to delete.
- To delete the app version, click Delete .
What's next
-
Learn how to use Cloud SQL for MySQL with Rails .
-
Learn how to use Cloud SQL for PostgreSQL with Rails .
-
Learn how to run the Ruby Bookshelf sample in App Engine flexible environment .
-
Learn how to run the Ruby Bookshelf sample on Compute Engine .
-
Learn how to run the Ruby Bookshelf sample on GKE .