Virtual Gateway Ingress to Crystal service

As we can see during the workshop, the AWS App Mesh services enable you to add services to the mesh, whether they are running on EKS, ECS or EC2. So, what we are going to do now is to add the Crystal service, which is running on the ECS cluster, enabling access from outside the mesh to both App Mesh services inside de cluster.

We just need to add a gateway route to the Crystal service running en ECS.

VIRTUAL_GATEWAY=$(aws appmesh list-virtual-gateways --mesh-name appmesh-workshop | jq -r ".virtualGateways[].virtualGatewayName")
VIRTUAL_SERVICE=$(aws appmesh list-virtual-services --mesh-name appmesh-workshop | jq -r ' .virtualServices[] | select( .virtualServiceName | contains("crystal")).virtualServiceName') 

# Create gatweay route spec json
cat <<-EOF > ~/environment/eks-scripts/gateway-route-ecs-spec.json
{
  "httpRoute": {
    "action": {
      "target": {
        "virtualService": {
          "virtualServiceName": "$VIRTUAL_SERVICE"
        }
      }
    },
    "match": {
      "prefix": "/ecs"
    }
  }
}
EOF

aws appmesh create-gateway-route --gateway-route-name gateway-route-ecs --mesh-name appmesh-workshop --spec file://~/environment/eks-scripts/gateway-route-ecs-spec.json --virtual-gateway-name $VIRTUAL_GATEWAY

Let’s test our new route.

Connect to the EC2 instance outside the mesh in order to test reachability from external requests to the mesh using the virtual gateway ingress

EXTERNAL_EC2=$(aws ec2 describe-instances --filters Name=tag:Usage,Values=ExternalEC2Instance | jq -r '.Reservations[].Instances[].InstanceId')

aws ssm start-session --target $EXTERNAL_EC2

And finally, let’s get the FQDN of the NLB that was created as part of the K8s Service of type LoadBalancer.

NLB_ENDPOINT=$(kubectl get service -n appmesh-workshop-ns -o json | jq -r ".items[].status.loadBalancer.ingress[].hostname")

Let’s try to connect

curl -v $NLB_ENDPOINT/ecs/crystal

You should now see a response similar to the one below

crystal