$ odo login -u developer -p developer
odo allows you to create a multicomponent application, modify it, and link its components in an easy and automated way.
This example describes how to deploy a multicomponent application - a shooter game. The application consists of a front-end Node.js component and a back-end Java component.
odo is installed.
You have a running OpenShift Dedicated cluster. Developers can use CodeReady Containers (CRC) to deploy a local OpenShift Dedicated cluster quickly.
Maven is installed.
Log in to an OpenShift Dedicated cluster:
$ odo login -u developer -p developer
Create a new directory for your components:
$ mkdir my_components $ cd my_components
Download the example back-end and front-end applications:
$ git clone https://github.com/openshift-evangelists/Wild-West-Backend backend $ git clone https://github.com/openshift-evangelists/Wild-West-Frontend frontend
Create a new project:
$ odo project create myproject ✓ Project 'myproject' is ready for use ✓ New project created and now using project : myproject
openjdk18 into the cluster:
$ oc import-image openjdk18 \ --from=registry.access.redhat.com/redhat-openjdk-18/openjdk18-openshift --confirm oc annotate istag/openjdk18:latest tags=builder
Tag the image as
builder to make it accesible for odo:
$ oc annotate istag/openjdk18:latest tags=builder
odo catalog list components to see the created image:
$ odo catalog list components Odo Supported OpenShift Components: NAME PROJECT TAGS nodejs openshift 10,8,8-RHOAR,latest openjdk18 myproject latest
Change directory to the back-end source directory and check that you have the correct files in the directory:
$ cd ~/backend $ ls debug.sh pom.xml src
Build the back-end source files with Maven to create a JAR file:
$ mvn package ... [INFO] -------------------------------------- [INFO] BUILD SUCCESS [INFO] -------------------------------------- [INFO] Total time: 2.635 s [INFO] Finished at: 2019-09-30T16:11:11-04:00 [INFO] Final Memory: 30M/91M [INFO] --------------------------------------
Create a component configuration of Java component-type named
$ odo create openjdk18 backend --binary target/wildwest-1.0.jar ✓ Validating component [1ms] Please use `odo push` command to create the component with source deployed
Now the configuration file
config.yaml is in the local directory of the back-end component that contains information about the component for deployment.
Check the configuration settings of the back-end component in the
config.yaml file using:
$ odo config view COMPONENT SETTINGS ------------------------------------------------ PARAMETER CURRENT_VALUE Type openjdk18 Application app Project myproject SourceType binary Ref SourceLocation target/wildwest-1.0.jar Ports 8080/TCP,8443/TCP,8778/TCP Name backend MinMemory MaxMemory DebugPort Ignore MinCPU MaxCPU
Push the component to the OpenShift Dedicated cluster.
$ odo push Validation ✓ Checking component [6ms] Configuration changes ✓ Initializing component ✓ Creating component [124ms] Pushing to component backend of type binary ✓ Checking files for pushing [1ms] ✓ Waiting for component to start [48s] ✓ Syncing files to the component [811ms] ✓ Building component [3s]
odo push, OpenShift Dedicated creates a container to host the back-end component, deploys the container into a Pod running on the OpenShift Dedicated cluster, and starts the
The status of the action in odo:
odo log -f 2019-09-30 20:14:19.738 INFO 444 --- [ main] c.o.wildwest.WildWestApplication : Starting WildWestApplication v1.0 onbackend-app-1-9tnhc with PID 444 (/deployments/wildwest-1.0.jar started by jboss in /deployments)
The status of the back-end component:
$ odo list APP NAME TYPE SOURCE STATE app backend openjdk18 file://target/wildwest-1.0.jar Pushed
Change the current directory to the front-end directory:
$ cd <directory-name>
List the contents of the directory to see that the front end is a Node.js application.
$ ls assets bin index.html kwww-frontend.iml package.json package-lock.json playfield.png README.md server.js
The front-end component is written in an interpreted language (Node.js); it does not need to be built.
Create a component configuration of Node.js component-type named
$ odo create nodejs frontend ✓ Validating component [5ms] Please use `odo push` command to create the component with source deployed
Push the component to a running container.
$ odo push Validation ✓ Checking component [8ms] Configuration changes ✓ Initializing component ✓ Creating component [83ms] Pushing to component frontend of type local ✓ Checking files for pushing [2ms] ✓ Waiting for component to start [45s] ✓ Syncing files to the component [3s] ✓ Building component [18s] ✓ Changes successfully pushed to component
Components running on the cluster need to be connected in order to interact. OpenShift Dedicated provides linking mechanisms to publish communication bindings from a program to its clients.
List all the components that are running on the cluster:
$ odo list APP NAME TYPE SOURCE STATE app backend openjdk18 file://target/wildwest-1.0.jar Pushed app frontend nodejs file://./ Pushed
Link the current front-end component to the backend:
$ odo link backend --port 8080 ✓ Component backend has been successfully linked from the component frontend Following environment variables were added to frontend component: - COMPONENT_BACKEND_HOST - COMPONENT_BACKEND_PORT
The configuration information of the back-end component is added to the front-end component and the front-end component restarts.
Create an external URL for the application:
$ cd frontend $ odo url create frontend --port 8080 ✓ URL frontend created for component: frontend To create URL on the OpenShift cluster, use `odo push`
Apply the changes:
$ odo push Validation ✓ Checking component [21ms] Configuration changes ✓ Retrieving component data [35ms] ✓ Applying configuration [29ms] Applying URL changes ✓ URL frontend: http://frontend-app-myproject.192.168.42.79.nip.io created Pushing to component frontend of type local ✓ Checking file changes for pushing [1ms] ✓ No file changes detected, skipping build. Use the '-f' flag to force the build.
Open the URL in a browser to view the application.
If an application requires permissions to the active Service Account to access the OpenShift Dedicated namespace and delete active pods, the following error may occur when looking at
To resolve this error, add permissions for the Service Account role:
$ oc policy add-role-to-group view system:serviceaccounts -n <project> $ oc policy add-role-to-group edit system:serviceaccounts -n <project>
Do not do this on a production cluster.
Change the local directory to the front-end directory:
$ cd ~/frontend
Monitor the changes on the file system using:
$ odo watch
index.html file to change the displayed name for the game.
A slight delay is possible before odo recognizes the change.
odo pushes the changes to the front-end component and prints its status to the terminal:
File /root/frontend/index.html changed File changed Pushing files... ✓ Waiting for component to start ✓ Copying files to component ✓ Building component
Refresh the application page in the web browser. The new name is now displayed.