test-utils.sh

#!/bin/bash

# Copyright 2017 The Kubernetes Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

source $(dirname "${BASH_SOURCE[0]}")/utils.sh

# RESTART_WAIT_PERIOD is the period to wait before restarting containerd.
RESTART_WAIT_PERIOD=${RESTART_WAIT_PERIOD:-10}
# CONTAINERD_FLAGS contains all containerd flags.
CONTAINERD_FLAGS="--log-level=debug "

# Use a configuration file for containerd.
CONTAINERD_CONFIG_FILE=${CONTAINERD_CONFIG_FILE:-""}
# CONTAINERD_TEST_SUFFIX is the suffix appended to the root/state directory used
# by test containerd.
CONTAINERD_TEST_SUFFIX=${CONTAINERD_TEST_SUFFIX:-"-test"}
# The containerd root directory.
CONTAINERD_ROOT=${CONTAINERD_ROOT:-"/var/lib/containerd${CONTAINERD_TEST_SUFFIX}"}
# The containerd state directory.
CONTAINERD_STATE=${CONTAINERD_STATE:-"/run/containerd${CONTAINERD_TEST_SUFFIX}"}
# The containerd socket address.
CONTAINERD_SOCK=${CONTAINERD_SOCK:-unix://${CONTAINERD_STATE}/containerd.sock}
# The containerd binary name.
CONTAINERD_BIN=${CONTAINERD_BIN:-"containerd${CONTAINERD_TEST_SUFFIX}"}
if [ -f "${CONTAINERD_CONFIG_FILE}" ]; then
  CONTAINERD_FLAGS+="--config ${CONTAINERD_CONFIG_FILE} "
fi
CONTAINERD_FLAGS+="--address ${CONTAINERD_SOCK#"unix://"} \
  --state ${CONTAINERD_STATE} \
  --root ${CONTAINERD_ROOT}"

containerd_groupid=

# test_setup starts containerd.
test_setup() {
  local report_dir=$1
  # Start containerd
  if [ ! -x "${ROOT}/_output/containerd" ]; then
    echo "containerd is not built"
    exit 1
  fi
  # rename the test containerd binary, so that we can easily
  # distinguish it.
  cp ${ROOT}/_output/containerd ${ROOT}/_output/${CONTAINERD_BIN}
  set -m
  # Create containerd in a different process group
  # so that we can easily clean them up.
  keepalive "sudo PATH=${PATH} ${ROOT}/_output/${CONTAINERD_BIN} ${CONTAINERD_FLAGS}" \
    ${RESTART_WAIT_PERIOD} &> ${report_dir}/containerd.log &
  pid=$!
  set +m
  containerd_groupid=$(ps -o pgid= -p ${pid})
  # Wait for containerd to be running by using the containerd client ctr to check the version
  # of the containerd server. Wait an increasing amount of time after each of five attempts
  local -r ctr_path=$(which ctr)
  if [ -z "${ctr_path}" ]; then
    echo "ctr is not in PATH"
    exit 1
  fi
  local -r crictl_path=$(which crictl)
  if [ -z "${crictl_path}" ]; then
    echo "crictl is not in PATH"
    exit 1
  fi
  readiness_check "sudo ${ctr_path} --address ${CONTAINERD_SOCK#"unix://"} version"
  readiness_check "sudo ${crictl_path} --runtime-endpoint=${CONTAINERD_SOCK} info"
}

# test_teardown kills containerd.
test_teardown() {
  if [ -n "${containerd_groupid}" ]; then
    sudo pkill -g ${containerd_groupid}
  fi
}

# keepalive runs a command and keeps it alive.
# keepalive process is eventually killed in test_teardown.
keepalive() {
  local command=$1
  echo ${command}
  local wait_period=$2
  while true; do
    ${command}
    sleep ${wait_period}
  done
}

# readiness_check checks readiness of a daemon with specified command.
readiness_check() {
  local command=$1
  local MAX_ATTEMPTS=5
  local attempt_num=1
  until ${command} &> /dev/null || (( attempt_num == MAX_ATTEMPTS ))
  do
      echo "$attempt_num attempt \"$command\"! Trying again in $attempt_num seconds..."
      sleep $(( attempt_num++ ))
  done
}