# kube

This repo contains some kubernetes test stuff

## testapp

The testapp consists of three parts:

* srv - the frontend server
* db - simulating a database backend that gets called
* api - another service that calls an external service (httpbin.org)

Topology:

```
         +--- db
        /
srv ---+
        \
         +--- api --- httpbin.org
```

### Prepare

You need to have access from you local machine to the container registry deployed in you cluster on port 5000:

You can use ssh port-forwarding: `ssh k8s-master -L 5000:127.0.0.1:5000`

You need a local docker installation to build and upload the containers.

For the normal deployment the nginx ingress controller is used.

#### Ingress traffic

To get traffic to the ingress controller, install an nginx tcp proxy on the master node:

Install nginx: `apt install nginx -y`

Configure nginx to forward traffic to the node ports.
First get the ports of your ingress controller.

Look for the `80:<nodeport>` and `443:<nodeport>` mappings.

* nginx: `kubectl -n ingress-nginx get svc ingress-nginx`
* Istio: `kubectl -n istio-system get svc istio-ingressgateway`

Now add all your worker nodes as stream backends with the ports:

```
cat <<EOF> /etc/nginx/nginx.conf
load_module /usr/lib/nginx/modules/ngx_stream_module.so;
events {
    worker_connections  1024;
}
stream {
    upstream stream_backend_80 {
        server 192.168.0.3:31380;
        server 192.168.0.4:31380;
        server 192.168.0.5:31380;
    }
    server {
        listen     80;
        proxy_pass stream_backend_80;
    }

    upstream stream_backend_443 {
        server 192.168.0.3:31390;
        server 192.168.0.4:31390;
        server 192.168.0.5:31390;
    }
    server {
        listen     443;
        proxy_pass stream_backend_443;
    }
}
EOF
```

Restart nginx: `systemctl restart nginx`

Now you can access your ingress via the masters IP on port 80 and 443.

### Build

New build the containers and upload them.

#### SRV

```
cd testapp/srv
VERSION=v1 make
```

#### DB

```
cd testapp/db
VERSION=v1 make
```

#### API

```
cd testapp/api
VERSION=v1 make
```

### Deploy

Deploy your application stack either using the simple versions or the `-istio` versions.

To use `-istio` versions you need to install istio in your cluster first.

**Note:** Change the `k8s-testapp.example.com` domain in the `srv` manifests to your domain.

#### Simple

```
cd testapp
kubectl apply -f api/api-v1.yaml
kubectl apply -f db/db.yaml
kubectl apply -f srv/srv-v1.yaml
```

#### Istio

```
cd testapp
kubectl apply -f api/api-v1-istio.yaml
kubectl apply -f db/db.yaml
kubectl apply -f srv/srv-v1-istio.yaml
```