This quickstart shows you how to create a small App Engine application that displays a short message.
Before you begin
Before running and deploying this sample, take the following steps:
Use the Cloud Platform Console to create a new Cloud Platform project,
create an App Engine application, and enable billing:
Go to App Engine
When prompted, select the region where you want your App Engine application located and then enable billing.
- Install the following prerequisites locally:
Alternatively: You can use
Google Cloud Shell, which
comes with git and Cloud SDK already installed, and
many other features, such as language
support and code editors.
After Google Cloud Shell is launched, you can proceed with the rest of this tutorial and execute your commands within Cloud Shell.
App Engine locations
App Engine is regional, which means the infrastructure that runs your apps is located in a specific region and is managed by Google to be redundantly available across all the zones within that region.
Meeting your latency, availability, or durability requirements are primary factors for selecting the region where your app's are run. You can generally select the region nearest to your app's users but you should consider the location of the other Cloud Platform products and services that are utilized by your app. Using services across multiple locations can affect your app's latency as well as pricing.
App Engine is available in the following regions:
Download the Hello World app
We've created a simple Hello World app for Ruby so you can quickly get a feel for deploying an app to the App Engine flexible environment. Follow these steps from a command line to download Hello World to your local machine.
Download the sample app and navigate into the app directory:
Clone the Hello World sample app repository to your local machine:
git clone https://github.com/GoogleCloudPlatform/ruby-docs-samples
Alternatively, you can download the sample as a zip file and extract it.
Change to the directory that contains the sample code:
Run Hello World on your local machine
To run the Hello World app on your local computer:
Install dependencies for this project by entering the following command:
Start a local web server:
bundle exec ruby app.rb -p 8080
In your web browser, enter the following address:
You can see the Hello World message from the sample app displayed in the page.
In your terminal window, press Ctrl+C to exit the web server.
Deploy and run Hello World on App EngineTo deploy your app to the App Engine flexible environment:
- Deploy the Hello World app by running the following
gcloud app deployLearn about the optional flags.
--versionflag to specify an ID that uniquely identifies that version of your app, otherwise one is generated for you. Example:
--projectflag to specify an alternate Cloud Platform project ID to what you initialized as the default in the
gcloud app deploy --version pre-prod-5 --project my-sample-app
- Include the
Launch your browser and view the app at
http://YOUR_PROJECT_ID.appspot.com, by running the following command:
gcloud app browse
Congratulations! You've deployed your first Ruby app to App Engine flexible environment!
See the following sections for information about cleaning up as well as links to the possible next steps that you can take.
- Deploy the Hello World app by running the following command from the
To avoid incurring charges, you can delete your Cloud Platform project to stop billing for all the resources used within that project.
- In the Cloud Platform Console, go to the Projects page.
- In the project list, select the project you want to delete and click Delete project.
- In the dialog, type the project ID, and then click Shut down to delete the project.
What's nextNow that you've accomplished Hello World, you can start exploring your next sample app: the Bookshelf app. The Bookshelf app is a more complete, yet still basic Ruby web app that uses multiple Cloud Platform features, such as data storage, authentication, logging, pub/sub, and more.
For more information about the App Engine flexible environment, see App Engine Flexible Environment.
Hello World code review
Hello World is the simplest possible App Engine app, as it contains only one service, has only one version, and all of the code is located within the app's root directory. This section describes each of the app files in detail.
The Hello World app is a very basic one-file Sinatra application:
require "sinatra" get "/" do "Hello world!" end
file describes an application's deployment configuration:
runtime: ruby env: flex entrypoint: bundle exec ruby app.rb
app.yaml specifies the runtime used by
the app, and sets
env: flex, specifying that the app
uses the flexible environment.
For more information on how the Ruby runtime works, see The Ruby Runtime.
For more details about how to design your app to take advantage of versions and services, see An Overview of App Engine.
For more details about the configuration settings for App Engine, see Configuring Your App with app.yaml.
is used to specify the application's
is used to declare and install dependencies. The Hello World application
requires one Ruby gem: the
source "https://rubygems.org" gem "sinatra"