CloudState

You can implement your gRPC service using the current Cloudstate DSL.

Here I implement an Event sourcing service using as Data Store the InMemory option

• Protobuf files

• Event sourcing

Cloudstate deploy StatefulService using docker images, so the service that you implement must be save into a docker image that run that service.

• Plugin to Create and push image of the Service into docker hub

        <plugin>
                <groupId>io.fabric8</groupId>
                <artifactId>docker-maven-plugin</artifactId>
                <version>0.26.1</version>
                <configuration>
                    <images>
                        <image>
                            <alias>service</alias>
                            <name>politrons/shopping-cart:%l</name>
                            <build>
                                <from>java:8</from>
                                <tags>
                                    <tag>latest</tag>
                                </tags>
                                <assembly>
                                    <descriptorRef>artifact-with-dependencies</descriptorRef>
                                </assembly>
                                <entryPoint>
                                    <arg>java</arg>
                                    <arg>-cp</arg>
                                    <arg>/maven/*</arg>
                                    <arg>io.cloudstate.shopping.ShoppingCartMain</arg>
                                </entryPoint>
                            </build>
                        </image>
                    </images>
                </configuration>
                <executions>
                    <execution>
                        <id>build-docker-image</id>
                        <phase>package</phase>
                        <goals>
                            <goal>build</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>    

Using in the plugin ``politrons/shopping-cart:%l``` it means it will be publish in my personal docker hub politrons

• Create image Docker build
• Push image Docker push

Cloudstate use K8s with some operators to work as proxy, and route gRPC/Rest communication from the transport layer into the service, so the users can focus on business logic, and forget about transport layer, scalability and recover failing services.

• Delete namespace

  kubectl delete namespace cloudstate
  

• Create namespace

  kubectl create namespace cloudstate
  

• Download cloudstate yaml file that you can find here and deploy it.

  kubectl apply -n cloudstate -f src/main/resources/cloudstate.yaml
  
  

• Create a service yaml file, and add the StatefulStore, StatefulService and the Service to route connections from outside the cluster to the StatefulService

  apiVersion: cloudstate.io/v1alpha1
  kind: StatefulStore
  metadata:
    name: inmemory
  spec:
    type: InMemory
  ---
  
  apiVersion: cloudstate.io/v1alpha1
  kind: StatefulService
  metadata:
    name: cloudstate-shopping-cart
    labels:
      app: cloudstate-shopping-cart
  spec:
    datastore:
      name: inmemory
    containers:
      - image: politrons/shopping-cart:latest
  ---
  
  apiVersion: v1
  kind: Service
  metadata:
    name: cloudstate-shopping-cart-service
  spec:
    type: LoadBalancer
    ports:
      - port: 1981
        targetPort: 8013
    selector:
      app: cloudstate-shopping-cart
  

• Deploy service

      kubectl apply -n cloudstate -f src/main/resources/service.yaml
  
  

Consume service

• Get cart

  curl http://localhost:1981/carts/politrons //politrons is the user_Id
  
  

• Add products

  curl -X POST -H 'Content-Type: application/json' http://localhost:1981/cart/politrons/items/add -d '{"product_id":"uuidCode","name":"coca-cola","quantity":1}'
  curl -X POST -H 'Content-Type: application/json' http://localhost:1981/cart/politrons/items/add -d '{"product_id":"uuidCode1","name":"doritos","quantity":2}'
  curl -X POST -H 'Content-Type: application/json' http://localhost:1981/cart/politrons/items/add -d '{"product_id":"uuidCode2","name":"Budweiser","quantity":6}'
  
  

• Get item

  curl http://localhost:1981/cart/uuidCode
  
  

• Delete product

  curl http://localhost:1981/cart/politrons/items/uuidCode/remove