#!/usr/bin/env bash
# Copyright 2019 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.

# wrapper.sh handles setting up things before / after the test command $@
#
# usage: wrapper.sh my-test-command [my-test-args]
#
# Things wrapper.sh handles:
# - starting / stopping docker-in-docker
# -- configuring the docker daemon for IPv6
# - activating GCP service account credentials
# - ensuring GOPATH/bin is in PATH
#
# After handling these things / before cleanup, my-test-command will be invoked,
# and the exit code of my-test-command will be preserved by wrapper.sh

set -o errexit
set -o pipefail
set -o nounset

>&2 echo "wrapper.sh] [INFO] Wrapping Test Command: \`$*\`"
>&2 echo "wrapper.sh] [INFO] Running in: ${KRTE_IMAGE}"
>&2 echo "wrapper.sh] [INFO] See: https://github.com/kubernetes/test-infra/blob/master/images/krte/wrapper.sh"
printf '%0.s=' {1..80} >&2; echo >&2
>&2 echo "wrapper.sh] [SETUP] Performing pre-test setup ..."

cleanup(){
  if [[ "${DOCKER_IN_DOCKER_ENABLED:-false}" == "true" ]]; then
    >&2 echo "wrapper.sh] [CLEANUP] Cleaning up after Docker in Docker ..."
    docker ps -aq | xargs -r docker rm -f || true
    service docker stop || true
    >&2 echo "wrapper.sh] [CLEANUP] Done cleaning up after Docker in Docker."
  fi
}

early_exit_handler() {
  >&2 echo "wrapper.sh] [EARLY EXIT] Interrupted, entering handler ..."
  if [ -n "${WRAPPED_COMMAND_PID:-}" ]; then
    kill -TERM "$WRAPPED_COMMAND_PID" || true
  fi
  if [ -n "${EXIT_VALUE:-}" ]; then
    >&2 echo "Original exit code was ${EXIT_VALUE}, not preserving due to interrupt signal"
  fi
  cleanup
  >&2 echo "wrapper.sh] [EARLY EXIT] Completed handler ..."
  exit 1
}

trap early_exit_handler TERM INT

# optionally enable ipv6 docker
export DOCKER_IN_DOCKER_IPV6_ENABLED=${DOCKER_IN_DOCKER_IPV6_ENABLED:-false}
if [[ "${DOCKER_IN_DOCKER_IPV6_ENABLED}" == "true" ]]; then
  >&2 echo "wrapper.sh] [SETUP] Enabling IPv6 in Docker config ..."
  # enable ipv6
  sysctl net.ipv6.conf.all.disable_ipv6=0
  sysctl net.ipv6.conf.all.forwarding=1
  # enable ipv6 iptables
  modprobe -v ip6table_nat
  >&2 echo "wrapper.sh] [SETUP] Done enabling IPv6 in Docker config."
fi

# optionally enable iptables-nft
export DOCKER_IN_DOCKER_NFT_ENABLED=${DOCKER_IN_DOCKER_NFT_ENABLED:-false}
if [[ "${DOCKER_IN_DOCKER_NFT_ENABLED}" == "true" ]]; then
  >&2 echo "wrapper.sh] [SETUP] Enabling iptables-nft ..."
  # enable iptables-nft
  update-alternatives --set iptables /usr/sbin/iptables-nft
  update-alternatives --set ip6tables /usr/sbin/ip6tables-nft
  # enable nft iptables module
  modprobe -v nf_tables
  >&2 echo "wrapper.sh] [SETUP] Done enabling iptables-nft by default."
fi

# Check if the job has opted-in to docker-in-docker
export DOCKER_IN_DOCKER_ENABLED=${DOCKER_IN_DOCKER_ENABLED:-false}
if [[ "${DOCKER_IN_DOCKER_ENABLED}" == "true" ]]; then
  >&2 echo "wrapper.sh] [SETUP] Docker in Docker enabled, initializing ..."
  # If we have opted in to docker in docker, start the docker daemon,
  service docker start
  # the service can be started but the docker socket not ready, wait for ready
  WAIT_N=0
  while true; do
    # docker ps -q should only work if the daemon is ready
    docker ps -q > /dev/null 2>&1 && break
    if [[ ${WAIT_N} -lt 5 ]]; then
      WAIT_N=$((WAIT_N+1))
      echo "wrapper.sh] [SETUP] Waiting for Docker to be ready, sleeping for ${WAIT_N} seconds ..."
      sleep ${WAIT_N}
    else
      echo "wrapper.sh] [SETUP] Reached maximum attempts, not waiting any longer ..."
      break
    fi
  done
  echo "wrapper.sh] [SETUP] Done setting up Docker in Docker."
fi

# add $GOPATH/bin to $PATH
export GOPATH="${GOPATH:-${HOME}/go}"
export PATH="${GOPATH}/bin:${PATH}"
mkdir -p "${GOPATH}/bin"

# Authenticate gcloud, allow failures
if [[ -n "${GOOGLE_APPLICATION_CREDENTIALS:-}" ]]; then
  >&2 echo "wrapper.sh] activating service account from GOOGLE_APPLICATION_CREDENTIALS ..."
  gcloud auth activate-service-account --key-file="${GOOGLE_APPLICATION_CREDENTIALS}" || true
fi

if git rev-parse --is-inside-work-tree >/dev/null; then
  >&2 echo "wrapper.sh] [SETUP] Setting SOURCE_DATE_EPOCH for build reproducibility ..."
  # Use a reproducible build date based on the most recent git commit timestamp.
  SOURCE_DATE_EPOCH=$(git log -1 --pretty=%ct)
  export SOURCE_DATE_EPOCH
  >&2 echo "wrapper.sh] [SETUP] exported SOURCE_DATE_EPOCH=${SOURCE_DATE_EPOCH}"
fi

# actually run the user supplied command
printf '%0.s=' {1..80}; echo
>&2 echo "wrapper.sh] [TEST] Running Test Command: \`$*\` ..."
set +o errexit
"$@" &
WRAPPED_COMMAND_PID=$!
wait $WRAPPED_COMMAND_PID
EXIT_VALUE=$?
set -o errexit
>&2 echo "wrapper.sh] [TEST] Test Command exit code: ${EXIT_VALUE}"

# cleanup
cleanup

# preserve exit value from user supplied command
printf '%0.s=' {1..80} >&2; echo >&2
>&2 echo "wrapper.sh] Exiting ${EXIT_VALUE}"
exit ${EXIT_VALUE}
