openwhisk.md

Deploy Flightassist leveraging OpenWhisk functions

In this scenario, we will deploy Flightassist to use a function that queries the necessary weather data. This shows how you could implement simple microservices with OpenWhisk. This approach replaces containers with OpenWhisk actions to save space and runtime memory in your cluster. Thanks to OpenWhisk built-in system packages, which includes a weather API, we don't even have to write our own action to implement the weather forecast lookup.

First, follow the Kubernetes Cluster Tutorial to create your own cluster on Bluemix.

Then, install the container registry plugin for Bluemix CLI.

bx plugin install container-registry -r Bluemix

Next, build your own docker images and push them to your own bluemix container registry.

You may skip these steps through deploying the secrets if you performed the Flightassist microservices deployment on Kubernetes or Istio scenarios

Replace <namespace> with your own namespace, you can view your namespace by running bx cr namespaces

If you have an unauthorized error, run bx cr login to authorized your container-registry.

docker build -f main_application/Dockerfile.local -t registry.ng.bluemix.net/<namespace>/flightassist main_application
docker build -f flightassist-weather/Dockerfile.alpine -t registry.ng.bluemix.net/<namespace>/weather-service flightassist-weather
docker push registry.ng.bluemix.net/<namespace>/flightassist
docker push registry.ng.bluemix.net/<namespace>/weather-service

Then, you need to run the following commands to bind your Cloudant and Weather Insights services to your clusters.

bx cs cluster-service-bind {your-cluster-name} default mycloudant
bx cs cluster-service-bind {your-cluster-name} default myweatherinsights

Next, create secret to give FlightStats and TripIt API credentials for Flightassist. Modify the secret.yaml file with flightstats-app-id, flightstats-app-key, tripit-api-key, and tripit-api-secret.

Now, run the following commands to deploy the secret

kubectl create -f secret.yaml

Note : you need to delete all the services and deployments from any previous scenarios.

kubectl delete -f flightassist.yaml

Then, install OpenWhisk CLI and Mark down its credentials.

Next, edit flightassist_serverless.yaml and replace the <namespace> with your own namespace, <your-app-end-point-url> with your node ip and nodeport, and <your-openwhisk-auth> with your OpenWhisk authentication. You can run wsk property get --auth | awk '{print $3}' to view your OpenWhisk authentication.

Now, let's deploy the new Flightassist app with serverless capability

kubectl create -f flightassist_serverless.yaml

Congratulations, now your Flightassist application should be running on http://<your_node_ip>:30080. Also, you can learn about How to Use Flightassist and start testing your application.

Takeaway points

In this example, the weather microservice in the Flightassist app is a perfect use case to convert it into a function on OpenWhisk. It is an event-triggered app, a stateless app, there are no sessions to manage, don’t require persistence, and performs a simple logical step. Many microservices, which don’t need to be long running applications or tasks can easily, be converted into serverless functions. This essentially gives you benefits like scaling etc., as well as cost benefits that you pay for infrastructure only when the application is used.

Code Structure

File	Description
flightassist.js	Main application, start the express web server and calling the major AJAX functions
weather.js	Trigger actions in OpenWhisk to get the weather information
All JavaScript files (main_application/*.js)	The implementation of the flightstats and tripIt information, shared by all deployment options
package.json	List the packages required by the application
Dockerfile.local	Description of the Docker image
flightassist_serverless.yaml and secret.yaml	Specification file for the deployment of the service and secret in Kubernetes