6bd-org/pathfinder

This is an extension of MediumKube, which enhances kubernetes by introducing declarative service discovery mechanism

Pathfinder

CRD Development

First of all install kubebuilder

os=$(go env GOOS)
arch=$(go env GOARCH)

# download kubebuilder and extract it to tmp
curl -L https://go.kubebuilder.io/dl/2.3.1/${os}/${arch} | tar -xz -C /tmp/

# move to a long-term location and put it on your path
# (you'll need to set the KUBEBUILDER_ASSETS env var if you put it somewhere else)
sudo mv /tmp/kubebuilder_2.3.1_${os}_${arch} /usr/local/kubebuilder
export PATH=$PATH:/usr/local/kubebuilder/bin

Create a directory and do

kubebuilder init --domain xmbsmdsj
# This will generate an empty project
# Including entry, dependencies, initial kubernetes configs

Add an api Pathfinder

kubebuilder create api --group pathfinder --version v1 PathFinder

# We will need both type and controller for this, so select Yes for both
# This step setup data type and some utils code like deepcopy and Scheme registration for 
# Out CRD

How to use?

Step 1: Deploy CRD to your cluster

$ make install

Step 2: Build image for pathfinder controller

$ make docker-push

Step 3: Deploy third party components and pathfinder controller on cluster

# cert-manager is required for pathfinder to run
$ make deploy-thirdparty
$ make deploy

Step 4: Deploy Sample

make deploy-sample

Step 5: Setup region for your pathfinder

Just modify the region value in Pathfinder's spec

Step N: Make your service discoverable

In order to make service discoverable, you only need to add a few annotations to service object, like this

apiVersion: v1
kind: Service
metadata:
  annotations:
    XM-PathFinder-Region: some-region # Region must match existing path-finder's region
    XM-PathFinder-Service: Activated
    XM-PathFinder-ServiceName: my-svc

Use PathFinder client go

It is pretty straitforward to access PathFinders using go client.

// You can either use config files to access remote cluster
config, err := clientcmd.BuildConfigFromFlags("", config)

// Or just use in-cluster setup if you are running your app
// in k8s pod
config, err := rest.InClusterConfig()

// Create a pf client from kube config
pfclient, err := client.New(config)

// Perform your operations on pathfinder here