1.
Microservices in Practice with Ballerina,
Kubernetes and Istio
November 2019
Lakmal Warusawithana, Senior Director - Cloud Architecture, WSO2
@lakwarus

2.
Why Microservices?

3.
Agility

4.
Let’s write a
Microservice

5.
Inherently Async I/O

6.
JSON as a native type
json is just a union - () | int | float | string | map<json> | json[]
// JSON object
json payload = { "orderdata": { "id": 1, "name": "XYZ", "price": 2500 } };
//Access object values
json orderid = payload.orderdata.id;
//JSON arrays
json orders = {
"orderdata": [
{ "id": 1, "name": "XYZ", "price": 2500 },
{ "id": 2, "name": "ABC", "price": 3000 }
]
};

7.
XML as a native type
// Simple XML literal
xml x1 = xml`<name>Lakmal Warusawithana</name>`;
// XML with namespaces
xmlns "http://wso2.com" as ns0;
xml x2 = xml `<name id="123" status="married">
<ns0:fname>Lakmal</ns0:fname>
<ns0:lname>Warusawithana</ns0:lname>
</name>`;
// XML literal with interpolation
string lastName = "Warusawithana";
xml x3 = xml`<lname>${lastName}</lname>`;
// Concat XML values
xml x4 = x1 + x2 + x3;

8.
Let’s deploy the
Microservice

9.
apiVersion: apps/v1
kind: Deployment
metadata:
name: hello-deployment
labels:
app: hello
spec:
replicas: 1
selector:
matchLabels:
app: hello
template:
metadata:
labels:
app: hello
spec:
containers:
- name: hello
image: hello:latest
imagePullPolicy: "IfNotPresent"
ports:
- containerPort: 9090
Create a deployment.yaml

10.
apiVersion: "v1"
kind: "Service"
metadata:
labels:
app: "hello"
name: "hello"
spec:
ports:
- port: 9090
protocol: "TCP"
targetPort: 9090
selector:
app: "hello"
type: "NodePort"
Create a service.yaml

11.
However, those parts are not part of
the programming experience for the
developer.

12.
Ballerina Cloud Native
Support

13.
● @kubernetes:Deployment{}
● @kubernetes:Service{}
● @kubernetes:Ingress{}
● @kubernetes:HPA{}
● @kubernetes:Secret{}
● @kubernetes:ConfigMap{}
Supported K8s and Istio Kinds
● @kubernetes:PersistentVolumeClaim{}
● @kubernetes:ResourceQuota{}
● @kubernetes:Job{}
● @openshift:Route{}
● @istio:Gateway{}
● @istio:VirtualService{}

14.
● Ballerina helps to write Microservices by providing
network abstraction as first class language constructs
● Ballerina natively understand Cloud Native platforms
like Docker, Kubernetes and Istio.
● Ballerina removes gap between developers and Ops.
● Ballerina and Kubernetes support agile development to
deployment and improve productivity.
Takeaways

15.
How to get involved
Learn more
Open source
Get support
http://ballerina.io
http://github.com/ballerina-platform/
Stack Overflow #ballerina tag