Spring-Boot REST Camel XML

This example demonstrates how to configure Camel routes in Spring Boot via a Spring XML configuration file.

The application utilizes the Spring @ImportResource annotation to load a Camel Context definition via a camel-context.xml file on the classpath.

Building

The example can be built with

mvn clean install

Running the example locally

The example can be run locally using the following Maven goal:

mvn spring-boot:run

Zero Downtime - Hot Reconfiguration of your Camel microservice on OpenShift

It is assumed a running OpenShift platform is already running. If not you can find details how to get started.

Assuming your current shell is connected to OpenShift so that you can type the following command to package your microservice, run it on OpenShift and get the output the logs from the running pods :

mvn clean install fabric8:deploy -Dfabric8.deploy.createExternalUrls=true fabric8:log

The goal fabric8:log tails the log of our microservice that’s deployed via the fabric8:deploy goal, and we can check when our micrservice is started.

By enabling the following property fabric8.deploy.createExternalUrls it will create an external Url to reach our Rest Endpoint. To get this Url, you have simply to run the following command:

$ oc get route
NAME                       HOST/PORT                                                   PATH      SERVICES                   PORT      TERMINATION
camel-springboot-rest-os   camel-springboot-rest-os-springboot.192.168.42.111.xip.io             camel-springboot-rest-os   <all>      

To invoke the Rest endpoint of your camel microservice every 1 second:

watch -n1 -c ab -n 10 http://camel-springboot-rest-os-springboot.192.168.42.111.xip.io/api/persons/Abel

Every 1.0s: curl http://camel-springboot-rest-os-springboot.192.168.42.111.xip.io/api/per...  Tue Jan 24 10:38:05 2017

  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
   0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0 100    85    0    85    0     0    665
      0 --:--:-- --:--:-- --:--:--   669
Hey Abel --> Enjoy your camel microservices | POD : camel-springboot-rest-os-10-4cxix

The output of the Rest service mention the pod that handle the request.

To configure your camel route, We will use a the following approach

Environment variables

All the endpoints of the route camel are defined as Environment variables properties. All these environment variables are declared in fabric8/deployment.yml

To update your Camel you have only to update the DeploymentConfig, like following:

$ oc env dc/camel-springboot-rest-os CAMEL_LOG_MSG="LOG UPDATED - This request is handled by this POD: {{env:HOSTNAME}}"
deploymentconfig "camel-springboot-rest-os" updated

Now you have just to watch the running pods:

oc get pods -w | grep Running
[aboucham@aboucham camel-springboot-rest-ose]$ oc get pods -w | grep Running
camel-springboot-rest-os-10-4cxix            1/1       Running     0          7m
camel-springboot-rest-os-11-deploy           1/1       Running     0          3s
camel-springboot-rest-os-11-y00ny            0/1       Running     0          3s
camel-springboot-rest-os-11-y00ny            1/1       Running     0          31s

Once the new pod is deployed & Running, you will see the output of our Rest service updated with the new pod running:

Hey Abel --> Enjoy your camel microservices | POD : camel-springboot-rest-os-11-y00ny

In addition to ZDD, one of the promise of the microservices is to allow to scale easily in order to get better performance of our service, then to do that you have 2 ways to do it:

Using deployment configuration:

$ oc scale dc/camel-springboot-rest-os --replicas=10
deploymentconfig "camel-springboot-rest-os" scaled

or fabric8 maven plugin:

mvn fabric8:start -Dfabric8.replicas=10

Enjoy!!