Getting started with Java on Compute Engine

Running the app in Cloud Shell

1. In Cloud Shell, start a local web server:

     mvn 
     
    - 
    Plocal 
     
    clean 
     
    jetty 
    : 
    run 
    - 
    exploded 
     
    - 
    DprojectID 
    = 
    YOUR 
    - 
    PROJECT 
    - 
    ID 
    
   

2. In Cloud Shell, click Web preview, and select Preview on port 8080. This opens a new window with your running app.

   In your web browser, you see some Hello World text, served from your local machine.

3. When you're ready to move on, stop the local web server by pressing Control+C in Cloud Shell.

Deploying to a single instance

This section walks you through running a single instance of your app on Compute Engine.

From Cloud Shell, you can deploy to a single Compute Engine instance virtual machine (VM) which runs your app.

Use a startup script to initialize an instance

You need a way to instruct your instance to download and run your code. An instance can have a startup script that runs whenever the instance is started or restarted.

A startup script runs when an instance first boots.

  set 
  
-e set 
  
-v # Talk to the metadata server to get the project id 
 PROJECTID 
 = 
 $( 
curl  
-s  
 "http://metadata.google.internal/computeMetadata/v1/project/project-id" 
  
-H  
 "Metadata-Flavor: Google" 
 ) 
 echo 
  
 "Project ID: 
 ${ 
 PROJECTID 
 } 
 " 
 # Install dependencies from apt 
apt-get  
install  
-yq  
openjdk-11-jdk  
git  
maven

mvn  
--version # Jetty Setup 
mkdir  
-p  
/opt/jetty/temp
mkdir  
-p  
/var/log/jetty # Get Jetty 
curl  
-L  
https://repo1.maven.org/maven2/org/eclipse/jetty/jetty-distribution/9.4.13.v20181111/jetty-distribution-9.4.13.v20181111.tar.gz  
-o  
jetty9.tgz
tar  
xf  
jetty9.tgz  
--strip-components = 
 1 
  
-C  
/opt/jetty # Add a Jetty User 
useradd  
--user-group  
--shell  
/bin/false  
--home-dir  
/opt/jetty/temp  
jetty cd 
  
/opt/jetty # Add running as "jetty" 
java  
-jar  
/opt/jetty/start.jar  
--add-to-startd = 
setuid cd 
  
/ # Clone the source repository. 
git  
clone  
https://github.com/GoogleCloudPlatform/getting-started-java cd 
  
getting-started-java/gce # Build the .war file and rename. 
 # very important - by renaming the war to root.war, it will run as the root servlet. 
mvn  
clean  
package  
-q
mv  
target/getting-started-gce-1.0-SNAPSHOT.war  
/opt/jetty/webapps/root.war # Make sure "jetty" owns everything. 
chown  
--recursive  
jetty  
/opt/jetty # Configure the default paths for the Jetty service 
cp  
/opt/jetty/bin/jetty.sh  
/etc/init.d/jetty echo 
  
 "JETTY_HOME=/opt/jetty" 
 > 
/etc/default/jetty { 
  
 echo 
  
 "JETTY_BASE=/opt/jetty" 
  
 echo 
  
 "TMPDIR=/opt/jetty/temp" 
  
 echo 
  
 "JAVA_OPTIONS=-Djetty.http.port=80" 
  
 echo 
  
 "JETTY_LOGS=/var/log/jetty" 
 } 
 >> 
/etc/default/jetty # Reload daemon to pick up new service 
systemctl  
daemon-reload # Install logging monitor. The monitor will automatically pickup logs sent to syslog. 
curl  
-sSO  
https://dl.google.com/cloudagents/add-logging-agent-repo.sh
sudo  
bash  
add-logging-agent-repo.sh  
--also-install

service  
google-fluentd  
restart  
&

service  
jetty  
start
service  
jetty  
check echo 
  
 "Startup Complete" 
 

The startup script performs these tasks:

• Installs Java 11 and makes it the default version.

• Installs and configures Jetty.

• Copies the Java WAR file from the Cloud Storage bucket to Jetty's webapps and renames it root.war . This makes it the root servlet, so it doesn't need to be named in the URL.

• Installs the Cloud Logging agent and configures it to monitor the app logs. This means that the logging configured in the previous steps of this tutorial are uploaded just as if you were using the App Engine flexible environment.

Create and configure a Compute Engine instance

1. Create a Compute Engine instance:

   gcloud  
   compute  
   instances  
   create  
   my-app-instance  
   
     
   --image-family = 
   debian-10  
   
     
   --image-project = 
   debian-cloud  
   
     
   --machine-type = 
   g1-small  
   
     
   --scopes  
   userinfo-email,cloud-platform  
   
     
   --metadata-from-file  
   startup-script = 
   gce/startup-script.sh  
   
     
   --zone  
    YOUR_ZONE 
     
   
     
   --tags  
   http-server  
   

   Replace YOUR_ZONE with a development zone, for example us-central1-a . For more information on regions and zones, see Geography and regions .

   This creates a new instance, allows it to access Google Cloud services, and runs your startup script. The instance name is my-app-instance .

2. Check the progress of the instance creation:

   gcloud compute instances get-serial-port-output my-app-instance --zone YOUR_ZONE 
   

   When the startup script is complete, you see the following message:

   startup-script: INFO Finished running startup scripts.

3. Create a firewall rule to allow traffic to your instance:

     gcloud 
     
    compute 
     
    firewall 
    - 
    rules 
     
    create 
     
    default 
    - 
    allow 
    - 
    http 
    - 
    80 
     
    \ 
     
    -- 
    allow 
     
    tcp 
    : 
    80 
     
    \ 
     
    -- 
    source 
    - 
    ranges 
     
    0.0.0.0 
    / 
    0 
     
    \ 
     
    -- 
    target 
    - 
    tags 
     
    http 
    - 
    server 
     
    \ 
     
    -- 
    description 
     
    "Allow port 80 access to http-server" 
    
   

4. Get the external IP address of your instance:

     gcloud 
     
    compute 
     
    instances 
     
    list 
    
   

5. To see your app running, enter this URL in your browser:

   http:// YOUR_INSTANCE_IP 
   

   Replace YOUR_INSTANCE_IP with the external IP address of your instance.

Manage and monitor an instance

You can use the Google Cloud console to monitor and manage your instance.

1. In the Google Cloud console, go to the VM instancespage.

   Go to VM instances

2. In the list of virtual machine instances, click SSHin the row of the instance that you want to connect to.

3. To view all of the logs generated by your Compute Engine resources, go to the Logs Explorer page.

   Go to Logs Explorer

   Cloud Logging is automatically configured to gather logs from various common services, including syslog .