Implement runner for e2e tests (#548)

* implement a runner for e2e tests

* move e2e tests to a Docker container

* integrate e2e tests into build pipelines

* add tests for multi-namespace support and logical backup jobs

* @FxKu implement the first e2e test for failovers

e2e/run.sh

@@ -0,0 +1,58 @@
+#!/usr/bin/env bash
+
+# enable unofficial bash strict mode
+set -o errexit
+set -o nounset
+set -o pipefail
+IFS=$'\n\t'
+
+readonly cluster_name="postgres-operator-e2e-tests"
+readonly operator_image=$(docker images --filter=reference="registry.opensource.zalan.do/acid/postgres-operator" --format "{{.Repository}}:{{.Tag}}"  | head -1)
+readonly e2e_test_image=${cluster_name}
+readonly kubeconfig_path="/tmp/kind-config-${cluster_name}"
+
+
+function start_kind(){
+
+  # avoid interference with previous test runs
+  if [[ $(kind-linux-amd64 get clusters | grep "^${cluster_name}*") != "" ]]
+  then
+    kind-linux-amd64 delete cluster --name ${cluster_name}
+  fi
+
+  kind-linux-amd64 create cluster --name ${cluster_name} --config ./e2e/kind-cluster-postgres-operator-e2e-tests.yaml
+  kind-linux-amd64 load docker-image "${operator_image}" --name ${cluster_name}
+  KUBECONFIG="$(kind-linux-amd64 get kubeconfig-path --name=${cluster_name})"
+  export KUBECONFIG
+}
+
+function set_kind_api_server_ip(){
+  # use the actual kubeconfig to connect to the 'kind' API server
+  # but update the IP address of the API server to the one from the Docker 'bridge' network
+  cp "${KUBECONFIG}" /tmp
+  readonly local kind_api_server_port=6443 # well-known in the 'kind' codebase
+  readonly local kind_api_server=$(docker inspect --format "{{ .NetworkSettings.IPAddress }}:${kind_api_server_port}" "${cluster_name}"-control-plane)
+  sed -i "s/server.*$/server: https:\/\/$kind_api_server/g" "${kubeconfig_path}"
+}
+
+function run_tests(){
+  docker run --rm --mount type=bind,source="$(readlink -f ${kubeconfig_path})",target=/root/.kube/config -e OPERATOR_IMAGE="${operator_image}" "${e2e_test_image}"
+}
+
+function clean_up(){
+  unset KUBECONFIG 
+  kind-linux-amd64 delete cluster --name ${cluster_name}
+  rm -rf ${kubeconfig_path}
+}
+
+function main(){
+
+  trap "clean_up" QUIT TERM EXIT
+
+  start_kind
+  set_kind_api_server_ip
+  run_tests
+  exit 0
+}
+
+main "$@"