entrypoint.sh

#!/usr/bin/env bash

set -o errexit
set -o errtrace
set -o pipefail

if [ -n "${REGION}" ]; then
  TARGET_REGION=${REGION}
else
  TARGET_REGION=eu-west-1
fi

if [ -n "${CLUSTER}" ]; then
  CLUSTER_NAME=${CLUSTER}
else
  NOW=$(date '+%s')
  CLUSTER_NAME=$GITHUB_ACTOR-$NOW
fi

echo "Provisioning EKS on Fargate cluster $CLUSTER_NAME in $TARGET_REGION"

# create EKS on Fargate cluster:
tmpdir=$(mktemp -d)
cat <<EOF >> ${tmpdir}/fg-cluster-spec.yaml
apiVersion: eksctl.io/v1alpha5
kind: ClusterConfig
metadata:
  name: $CLUSTER_NAME
  region: $TARGET_REGION
  version: '1.16'
iam:
  withOIDC: true
fargateProfiles:
  - name: defaultfp
    selectors:
      - namespace: serverless
      - namespace: kube-system
cloudWatch:
  clusterLogging:
    enableTypes: ["*"]
EOF
eksctl create cluster -f ${tmpdir}/fg-cluster-spec.yaml

# check if cluster if available
echo "Waiting for cluster $CLUSTER_NAME in $TARGET_REGION to become available"
sleep 10
cluster_status="UNKNOWN"
until [ "$cluster_status" == "ACTIVE" ]
do 
    cluster_status=$(eksctl get cluster $CLUSTER_NAME --region $TARGET_REGION -o json | jq -r '.[0].Status')
    sleep 3
done

# create serverless namespace for Fargate pods, make it the active namespace:
echo "EKS on Fargate cluster $CLUSTER_NAME is ready, configuring it:"
kubectl create namespace serverless
kubectl config set-context $(kubectl config current-context) --namespace=serverless

# patch kube-system namespace to run also on Fargate:
kubectl --namespace kube-system patch deployment coredns \
        --type json -p='[{"op": "remove", "path": "/spec/template/metadata/annotations/eks.amazonaws.com~1compute-type"}]'