The Java 8 / Jetty 9 runtime provides OpenJDK 8 and Eclipse Jetty 9 with support for the Java Servlet 3.1 Specification. For information about the specific Jetty version in this runtime, view the Jetty properties in the GitHub project for the runtime's image.
Download the latest version of the Google Cloud SDK or update your Cloud SDK to the current version:
gcloud components update
To deploy using Maven, you will need to add the App Engine Maven Plugin to your
<plugin> <groupId>com.google.cloud.tools</groupId> <artifactId>appengine-maven-plugin</artifactId> <version>2.2.0</version> </plugin>
Other options for deploying include the
gcloud app deploycommand or the App Engine Gradle plugin.
Organizing your files
Your source tree should look like this:
MyDir/ [pom.xml] [build.gradle] [index.yaml] [cron.yaml] [dispatch.yaml] src/main/ appengine/ app.yaml docker/ [Dockerfile] java/ com.example.mycode/ MyCode.java webapp/ [index.html] [jsp.jsp] WEB-INF/ [web.xml]
app.yaml file is required. Define a file that looks like this:
runtime: java env: flex handlers: - url: /.* script: this field is required, but ignored
The runtime image
gcr.io/google-appengine/jetty is automatically selected when
you deploy a WAR (
If you want to use this image as a base for a custom runtime, you can specify
runtime: custom in your
app.yaml file and then write the Dockerfile like
FROM gcr.io/google-appengine/jetty ADD your-application.war $APP_DESTINATION
These lines add the WAR in the correct location for the Docker container.
app.yaml settings are described in
These configuration files are optional:
Place these files at the top level of MyDir. If you use any these files, you
must deploy them separately with the
gcloud app deploy command.
web.xml is optional and only needed if you are not using Servlet 3.x annotations.
You can place static web content, as well as your JavaServer pages, in your
Jetty 9, which the App
Engine flexible environment uses as its Servlet container, uses
as the default JSP implementation and includes JSTL taglibs.
The Dockerfile file is optional and used to customize the Java runtime.
Enabling gzip compression
gzip handler is bundled with Jetty but not activated by default. To
activate this module, set the environment variable,
env_variables: JETTY_MODULES_ENABLE: 'gzip'
can speed up
the start time of your application by pre-scanning its content and generating
If you are using an
you can activate quickstart by executing
/scripts/jetty/quickstart.sh in your
Dockerfile, after the application WAR is added.
FROM launcher.gcr.io/google/jetty ADD your-application.war $JETTY_BASE/webapps/root.war # generate quickstart-web.xml RUN /scripts/jetty/quickstart.sh
You can set the following optional environment variables that are specific to the Java 8/Jetty 9 runtime. You can set OpenJDK 8 environment variables as well.
To set environment variables, use the
env_variables key in the
|Env Var||Maven Prop||Value/Comment|
||Comma separated list of
||Comma separated list of modules to enable by appending to
||Comma separated list of modules to disable by removing from
||Arguments passed to jetty's
||JVM runtime arguments|
Enhanced Cloud Logging (Beta)
When running on the App Engine flex environment, you can configure Java Util
Logging to send logs to Cloud Logging by setting the
JETTY_ARGS environment variable. For example:
env_variables: JETTY_ARGS: -Djava.util.logging.config.file=WEB-INF/logging.properties
You must provide a logging.properties file that configures a LoggingHandler as follows:
handlers=com.google.cloud.logging.LoggingHandler # Optional configuration .level=INFO com.google.cloud.logging.LoggingHandler.level=FINE com.google.cloud.logging.LoggingHandler.log=gae_app.log com.google.cloud.logging.LoggingHandler.formatter=java.util.logging.SimpleFormatter java.util.logging.SimpleFormatter.format=%3$s: %5$s%6$s
When testing in your local environment, you may use emulated Google cloud services, rather than remote Google cloud services. You can use the following emulators:
gcloud command to start them before you run your app:
gcloud beta emulators datastore start gcloud beta emulators pubsub start gcloud beta emulators bigtable start
Add these lines in your maven
pom.xml file to add the
Jetty 9 Maven Plugin:
<plugin> <groupId>org.eclipse.jetty</groupId> <artifactId>jetty-maven-plugin</artifactId> <version>9.4.2.v20170220</version> </plugin>
To run your app locally, use the Maven command:
Deploying your app
To initialize the Google Cloud SDK, run:
After completing the configurations, you can use the Google Cloud SDK to deploy
this directory containing the
app.yaml and WAR files using:
gcloud app deploy app.yaml
If you are using any of the optional configuration files (
dispatch.yaml) deploy them separately with the
command. For example:
gcloud app deploy cron.yaml
Use Maven to deploy your app:
mvn package appengine:deploy -Dapp.deploy.projectId=PROJECT_ID
Replace PROJECT_ID with the ID of your Cloud project. If
pom.xml file already
project ID, you don't need to include the
-Dapp.deploy.projectId property in the
command you run.
Use Gradle to deploy your app:
Customizing the Java 8 / Jetty 9 runtime
You don't need a Dockerfile to deploy your app into the Java 8/Jetty 9 runtime.
If your app requires additional configuration, you can explicitly provide a
Dockerfile to customize the Java runtime. The Dockerfile must include the base
gcr.io/google-appengine/jetty. You can add additional directives to the
Dockerfile to customize the Java runtime. See
Building Custom Runtimes.
Your Dockerfile should begin like this:
FROM gcr.io/google-appengine/jetty ADD your-application.war $APP_DESTINATION # YOUR DOCKER COMMANDS
In this case,
your-application.war is the name of the built WAR file
target/ directory (maven), or