tests/k8s: add utilities functions for the tests

The following functions were copied from CCv0's branch test's
integration/kubernetes/confidential/lib.sh. I did just smalls
refactorings (shortened their names and delinted shellcheck warnings):

- k8s_delete_all_pods_if_any_exists()
- k8s_wait_pod_be_ready()
- k8s_create_pod()
- assert_pod_fail()

Co-authored-by: Fabiano Fidêncio <fabiano.fidencio@intel.com>
Co-authored-by: Georgina Kinge <georgina.kinge@ibm.com>
Co-authored-by: Jordan Jackson <jordan.jackson@ibm.com>
Co-authored-by: Megan Wright <Megan.Wright@ibm.com>
Signed-off-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Co-authored-by: Wang, Arron <arron.wang@intel.com>

tests/integration/kubernetes/lib.sh

@@ -0,0 +1,74 @@
+#!/bin/bash
+# Copyright (c) 2021, 2022 IBM Corporation
+# Copyright (c) 2022, 2023 Red Hat
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+# This provides generic functions to use in the tests.
+#
+set -e
+
+# Delete all pods if any exist, otherwise just return
+#
+k8s_delete_all_pods_if_any_exists() {
+	[ -z "$(kubectl get --no-headers pods)" ] || \
+		kubectl delete --all pods
+}
+
+# Wait until the pod is not 'Ready'. Fail if it hits the timeout.
+#
+# Parameters:
+#	$1 - the sandbox ID
+#	$2 - wait time in seconds. Defaults to 120. (optional)
+#
+k8s_wait_pod_be_ready() {
+	local pod_name="$1"
+	local wait_time="${2:-120}"
+
+	kubectl wait --timeout="${wait_time}s" --for=condition=ready "pods/$pod_name"
+}
+
+# Create a pod and wait it be ready, otherwise fail.
+#
+# Parameters:
+#	$1 - the pod configuration file.
+#
+k8s_create_pod() {
+	local config_file="$1"
+	local pod_name=""
+
+	if [ ! -f "${config_file}" ]; then
+		echo "Pod config file '${config_file}' does not exist"
+		return 1
+	fi
+
+	kubectl apply -f "${config_file}"
+	if ! pod_name=$(kubectl get pods -o jsonpath='{.items..metadata.name}'); then
+		echo "Failed to create the pod"
+		return 1
+	fi
+
+	if ! k8s_wait_pod_be_ready "$pod_name"; then
+		# TODO: run this command for debugging. Maybe it should be
+		#       guarded by DEBUG=true?
+		kubectl get pods "$pod_name"
+		return 1
+	fi
+}
+
+# Create a pod then assert it fails to run. Use in tests that you expect the
+# pod creation to fail.
+#
+# Note: a good testing practice is to afterwards check that the pod creation
+# failed because of the expected reason.
+#
+# Parameters:
+#	$1 - the pod configuration file.
+#
+assert_pod_fail() {
+	local container_config="$1"
+	echo "In assert_pod_fail: $container_config"
+
+	echo "Attempt to create the container but it should fail"
+	! k8s_create_pod "$container_config" || /bin/false
+}