App Engine Maven Plugin Goals and Parameters

After you add the gcloud CLI-based App Engine Maven plugin to your project , the following App Engine-specific Maven goals are available:

Goal Description
appengine:cloudSdkLogin Sets the global gcloud CLI state for account.
appengine:deploy Stages and deploys an application to App Engine.
appengine:deployAll Stages and deploys an application with all of its valid yaml configurations simultaneously to App Engine.
appengine:deployCron Stages and deploys a cron.yaml configuration file to App Engine.
appengine:deployDispatch Stages and deploys a dispatch.yaml configuration file to App Engine.
appengine:deployDos Stages and deploys a dos.yaml configuration file to App Engine.
appengine:deployIndex Stages and deploys an index.yaml configuration file to App Engine.
appengine:deployQueue Stages and deploys a queue.yaml configuration file to App Engine.
appengine:help Displays help information on the App Engine Maven plugin.
appengine:run Runs the App Engine development server. When the server is running, it continuously checks to determine whether appengine-web.xml has changed. If it has, the server reloads the application. You do not need to stop and restart your application because of changes to appengine-web.xml. This goal is supported for the legacy bundled services.
appengine:stage Generates an application directory for deployment.
appengine:start Starts running the App Engine devserver asynchronously and then returns to the command line. When this goal runs, the behavior is the same as the run goal except that Maven continues processing goals and exits after the server is up and running. This goal is supported for the legacy bundled services.
appengine:stop Stops a running App Engine web development server. This goal is supported for the legacy bundled services.

For more information on how to set up and use Maven, see Using Maven.

Using parameters

Each goal has associated parameters that you can specify in the pom.xml file. For example:

<plugins>
   <plugin>
     <groupId>com.google.cloud.tools</groupId>
     <artifactId>appengine-maven-plugin</artifactId>
     <version>2.7.0</version>
     <configuration>
       <deploy.stopPreviousVersion>true</deploy.stopPreviousVersion>
       <cloudSdkHome>/usr/foo/path/to/cloudsdk</cloudSdkHome>
     </configuration>
  </plugin>
</plugins>

You can also define configuration parameters in the command line, following the pattern -D[USER_PROPERTY]=[PARAMETER_VALUE].

For example, to specify a directory to which to stage your application:

mvn appengine:stage -Dapp.stage.stagingDirectory=[YOUR_STAGING_DIRECTORY]

See the following sections for a list of the parameters that are available for each goal.

appengine:deploy

Stages and deploys an application to App Engine.

You can use the following parameters, some of which correspond to gcloud app deploy command line flags or gcloud app services command line flags:

Parameter Description User Property
appEngineDirectory The directory that contains app.yaml and other supported App Engine configuration files. Default is ${basedir}/src/main/appengine. app.stage.appEngineDirectory
artifact The location of the JAR or WAR archive to deploy. Default is ${project.build.directory}/${project.build.finalName}.${project.packaging}. app.stage.artifact
bucket The Cloud Storage bucket used to stage files associated with the deployment. If this argument is not specified, the application's default bucket is used. app.deploy.bucket
cloudSdkPath Optional parameter to configure the location of the Google Cloud CLI. Default is to automatically discover from the PATH or standard install location. cloudSdkPath
deployables The YAML files for the services or configurations you want to deploy. Default is the app.yaml file in the staging directory. If that is not found, attempts to automatically generate necessary configuration files (such as app.yaml) in the staging directory. app.deploy.deployables
dockerDirectory The directory containing the Dockerfile and other Docker resources. Default is ${basedir}/src/main/docker/. app.stage.dockerDirectory
imageUrl Deploy with a specific Docker image. ImageUrl must be a valid Artifact Registry name, for example, docker.pkg.dev/foo, where foo is the name of the image. app.deploy.imageUrl
projectId The Google Cloud project name to use for this invocation. Default is the current project selected when initializing gcloud. app.deploy.projectId
promote Promote the deployed version to receive all traffic. Default is True. app.deploy.promote
server The App Engine server to connect to. Typically, you do not need to change this value. app.deploy.server
stagingDirectory Required. The directory to which to stage the application. Default is ${project.build.directory}/appengine-staging. app.stage.stagingDirectory
stopPreviousVersion Stop the previously running version when deploying a new version that receives all traffic. app.deploy.stopPreviousVersion
version The version of the app that will be created or replaced by this deployment. If you do not specify a version, one will be generated for you. app.deploy.version

appengine:help

Displays help information on the App Engine Maven plugin. To display parameter details, call:

mvn appengine:help -Ddetail=true -Dgoal=[GOAL_NAME]

You can use the following parameters:

Parameter Description User Property
detail If true, display all settable properties for each goal. Default is False. detail
goal The name of the goal for which to show help. If unspecified, all goals will be displayed. goal
indentSize The number of spaces per indentation level. Should be a positive number. Default is 2. indentSize
lineLength The maximum length of a display line. Should be a positive number. Default is 80. lineLength

appengine:run

Runs the App Engine development web server. When the server is running, it continuously checks to determine whether appengine-web.xml has changed. If it has, the server reloads the application. This means that you do not need to stop and restart your application because of changes to appengine-web.xml.

You can use the following parameters, some of which correspond to the local development server command line flags:

Property Description Plugin configuration Command line configuration
automaticRestart Restart instances automatically when web application files (resources or class files) are changed. To configure Maven to put the compiled class files in the correct directory of the web app application, you must change the Maven outputDirectory setting:
<build>
  <outputDirectory>
    target/${project.artifactId}-${project.version}/WEB-INF/classes
  </outputDirectory>
  ...
<plugins>
...
devserver.automaticRestart app.devserver.automaticRestart
environment A map of environment variables to send to the local development server. Example:
<environment>
  <key1>value1</key1>
  <key2>value2</key2>
</environment>
      
devserver.environment app.devserver.environment
jvmFlags Additional arguments to pass to the java command when launching an instance of the app. May be specified more than once. Example:
<jvmFlags>
  <jvmFlag>-Xmx1024m</jvmFlag>
  <jvmFlag>-Xms256m</jvmFlag>
</jvmFlags>
      
devserver.jvmFlags app.devserver.jvmFlags
host Host name to which application services should bind. Default is localhost. devserver.host app.devserver.host
port Lowest port to which application services should bind. Default is 8080. devserver.port app.devserver.port
serverVersion Server version to launch, options are "1" and "2-alpha". Default is "1". devserver.serverVersion app.devserver.serverVersion
services Required. Path(s) to a directory containing a directory containing WEB-INF/web.xml. Default is build/exploded-app. devserver.services app.devserver.services

appengine:stage

Generates an application build directory for deployment.

You can use the following parameters:

Parameter Description User Property
appEngineDirectory The directory that contains app.yaml and other supported App Engine configuration files. Default is ${basedir}/src/main/appengine. app.stage.appEngineDirectory
artifact The location of the JAR or WAR archive to deploy. Default is ${project.build.directory}/${project.build.finalName}.${project.packaging}. app.stage.artifact
cloudSdkPath Optional parameter to configure the location of the gcloud CLI. cloudSdkPath
dockerDirectory The directory containing the Dockerfile and other Docker resources. Default is ${basedir}/src/main/docker/${basedir}/src/main/docker/. app.stage.dockerDirectory
stagingDirectory Required. The directory to which to stage the application. Default is ${project.build.directory}/appengine-staging app.stage.stagingDirectory

appengine:start

Starts running the App Engine development web server asynchronously and then returns to the command line. When this goal runs, the behavior is the same as the run goal except that Maven continues processing goals and exits after the server is up and running.

You can use the following parameters:

Property Description Plugin configuration Command line configuration
environment A map of environment variables to send to the local development server. Example:
<environment>
  <key1>value1</key1>
  <key2>value2</key2>
</environment>
      
devserver.environment app.devserver.environment
jvmFlags Additional arguments to pass to the java command when launching an instance of the app. May be specified more than once. Example:
<jvmFlags>
  <jvmFlag>-Xmx1024m</jvmFlag>
  <jvmFlag>-Xms256m</jvmFlag>
</jvmFlags>
      
devserver.jvmFlags app.devserver.jvmFlags
host Host name to which application services should bind. Default is localhost. devserver.host app.devserver.host
port Lowest port to which application services should bind. Default is 8080. devserver.port app.devserver.port
serverVersion Server version to launch, options are "1" and "2-alpha". Default is "1". devserver.serverVersion app.devserver.serverVersion
services Required. Path(s) to a directory containing a directory containing WEB-INF/web.xml. Default is build/exploded-app. devserver.services app.devserver.services
startSuccessTimeout Amount of time in seconds to wait for the Dev App Server to start in the background (when using appengineStart). devserver.startSuccessTimeout app.devserver.startSuccessTimeout

appengine:stop

Stops a running App Engine web development server.

You can use the following parameters:

Parameter Description Plugin configuration Command line configuration
host Host name to which the admin server should bind. Default is localhost devserver.adminHost app.devserver.adminHost
port Port to which the admin server should bind. Default is 8000. devserver.adminPort app.devserver.adminPort
cloudSdkHome Optional parameter to configure the location of the gcloud CLI. If this property is not specified, then the plugin automatically downloads the gcloud CLI. cloudSdkHome cloudSdkHome