#!/bin/bash
#
# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements.  See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership.  The ASF licenses this file
# to you 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.
#
# Entrypoint code for test-with-docker.py containers. test-with-docker.py
# will create Docker containers with this script as the entrypoint,
# with a variety of arguments. See test-with-docker.py for a more
# general overview.
#
# This assumes that the following are already mounted inside
# the container:
#   /etc/localtime                      -> /mnt/localtime
#     Helps timestamps be in the time zone of the host
#   $IMPALA_HOME [a git repo of Impala] -> /repo
#     Used to check out Impala afresh
#   $IMPALA_HOME/logs/docker/<n1>/<n2> -> /logs
#     Used to save logs out to host.
#     <n1> represents the --name passed into
#     test-with-docker for the test run. <n2>
#     indicates which specific container is being run.
#   ~/.ccache [configurable]            -> /ccache
#     Used to speed up builds.
#
# Usage:
#   entrypoint.sh build <uid>
#   entrypoint.sh test_suite <suite>
#      where <suite> is one of: BE_TEST JDBC_TEST CLUSTER_TEST
#                               EE_TEST_SERIAL EE_TEST_PARALLEL

# Starts or stops postgres
# The centos:7 Docker image doesn't allow systemctl to start postgresql,
# so we start it explicitly with pg_ctl.
function _pg_ctl() {
  if [ -f /etc/redhat-release ]; then
    if which systemctl; then
      sudo -u postgres PGDATA=/var/lib/pgsql/data bash -c "pg_ctl $1 -w --timeout=120 >> /var/lib/pgsql/pg.log 2>&1"
      return
    fi
  fi
  sudo service postgresql $1
}

# Install Python2 with pip2 and make them the default Python and pip commands
# on RedHat / CentOS 8.
# This has no notion of "default" Python, and can install both Python2 and Python3
# side by side. Impala currently needs Python2 as the default version.
# The function is adaptive; it performs only the necessary steps; it shares the installer
# logic with bin/bootstrap_system.sh
function install_python2_for_centos8() {
  if command -v python && [[ $(python --version 2>&1 | cut -d ' ' -f 2) =~ 2\. ]]; then
    echo "We have Python 2.x";
  else
    if ! command -v python2; then
      # Python2 needs to be installed
      dnf install -y python2
    fi
    # Here Python2 is installed, but is not the default Python.
    # 1. Link pip's version to Python's version
    alternatives --add-slave python /usr/bin/python2 /usr/bin/pip pip /usr/bin/pip2
    alternatives --add-slave python /usr/libexec/no-python  /usr/bin/pip pip \
        /usr/libexec/no-python
    # 2. Set Python2 (with pip2) to be the system default.
    alternatives --set python /usr/bin/python2
  fi
  # Here the Python2 runtime is already installed, add the dev package
  dnf -y install python2-devel
}

# Boostraps the container by creating a user and adding basic tools like Python and git.
# Takes a uid as an argument for the user to be created.
function build() {
  # Handy for testing.
  if [[ $TEST_TEST_WITH_DOCKER ]]; then
    # We sleep busily so that CPU metrics will show usage, to
    # better exercise the timeline code.
    echo sleeping busily for 4 seconds
    bash -c 'while [[ $SECONDS -lt 4 ]]; do :; done'
    return
  fi

  # Configure timezone, so any timestamps that appear are coherent with the host.
  configure_timezone

  # Assert we're superuser.
  [ "$(id -u)" = 0 ]
  if id $1 2> /dev/null; then
    echo "User with id $1 already exists. Please run this as a user id missing from " \
      "the base Ubuntu container."
    echo
    echo "Container users:"
    paste <(cut -d : -f3 /etc/passwd) <(cut -d : -f1 /etc/passwd) | sort -n
    exit 1
  fi
  if command -v apt-get > /dev/null; then
    apt-get update
    apt-get install -y sudo git lsb-release python
  elif grep 'release 8\.' /etc/redhat-release; then
    # WARNING: Install the following packages one by one!
    # Installing them in a common transaction breaks something inside yum/dnf,
    # and the subsequent step installing Python2 will fail with a GPG signature error.
    dnf -y install sudo
    dnf -y install which
    dnf -y install git-core

    install_python2_for_centos8
  else
    yum -y install which sudo git python
  fi

  if ! id impdev; then
    # Adduser is slightly different on CentOS and Ubuntu
    if which apt-get; then
      adduser --disabled-password --gecos "" --uid $1 impdev
    else
      adduser --uid $1 impdev
    fi
    echo "impdev ALL=(ALL) NOPASSWD:ALL" >> /etc/sudoers
  fi

  ulimit -a
  su impdev -c "$0 build_impdev"
}

# Sets up Impala environment
function impala_environment() {
  pushd /home/impdev/Impala
  export IMPALA_HOME=/home/impdev/Impala
  source bin/impala-config.sh
  popd
}

# Starts SSH and PostgreSQL; configures container as necessary;
# prepares Kudu for starting.
function boot_container() {
  pushd /home/impdev/Impala

  # Make log directories. This is typically done in buildall.sh.
  mkdir -p logs/be_tests logs/fe_tests/coverage logs/ee_tests logs/custom_cluster_tests

  # Update /etc/hosts to remove the entry for the unique docker hostname,
  # and instead point it to 127.0.0.1. Otherwise, HttpFS returns Location:
  # redirects to said hostname, but the relevant datanode isn't listening
  # on the wildcard address. bootstrap_system.sh does this as well, but
  # Docker creates a new /etc/hosts every time a container is created, so
  # this needs to be done here as well.
  #
  # "sed -i" in place doesn't work on Docker, because /etc/hosts is a bind mount.
  sed -e /$(hostname)/d /etc/hosts > /tmp/hosts
  echo "127.0.0.1 $(hostname -s) $(hostname)" >> /tmp/hosts
  sudo cp /tmp/hosts /etc/hosts

  echo Hostname: $(hostname)
  echo Hosts file:
  cat /etc/hosts

  popd
}

function start_minicluster {
  # The subshell here avoids the verbose output from set -x.
  (echo ">>> Starting PostgreSQL and SSH") 2> /dev/null
  pushd /home/impdev/Impala

  # Required for metastore
  _pg_ctl start

  # Required for starting HBase
  if [ -f /etc/redhat-release ]; then
    if which systemctl; then
      # centos7 doesn't support systemd running inside of docker to start daemons
      sudo /usr/sbin/sshd
    else
      sudo service sshd start
    fi
  else
    sudo service ssh start
  fi

  (echo ">>> Copying Kudu Data") 2> /dev/null
  # Move around Kudu's WALs to avoid issue with Docker filesystems (aufs and
  # overlayfs) that don't support os.rename(2) on directories, which Kudu
  # requires. We make a fresh copy of the data, in which case rename(2) works
  # presumably because there's only one layer involved. See
  # https://issues.apache.org/jira/browse/KUDU-1419.
  set -x
  pushd /home/impdev/Impala/testdata
  for x in cluster/cdh*/node-*/var/lib/kudu/*/wal; do
    echo $x
    # This mv takes time, as it's actually copying into the latest layer.
    mv $x $x-orig
    mkdir $x
    mv $x-orig/* $x
    rmdir $x-orig
  done
  popd

  # Wait for postgresql to really start; if it doesn't, Hive Metastore will fail to start.
  for i in {1..120}; do
    echo connecting to postgresql attempt $i
    if sudo -u postgres psql -c "select 1"; then
      break
    else
      sleep 2
    fi
  done
  sudo -u postgres psql -c "select 1"

  (echo ">>> Starting mini cluster") 2> /dev/null
  testdata/bin/run-all.sh

  popd
}

# Runs bootstrap_system.sh and then builds Impala.
function build_impdev() {
  # Assert we're impdev now.
  [ "$(id -un)" = impdev ]

  # Bump "Max processes" ulimit to the hard limit; default
  # on CentOS 6 can be 1024, which isn't enough for minicluster.
  ulimit -u $(cat /proc/self/limits | grep 'Max processes' | awk '{ print $4 }')
  ulimit -a

  # Link in ccache from host.
  ln -s /ccache /home/impdev/.ccache

  # Instead of doing a full "git clone" of /repo, which is the host's checkout,
  # we only fetch one branch, without tags. This keeps the checkout
  # considerably lighter.
  mkdir /home/impdev/Impala
  pushd /home/impdev/Impala
  git init
  git fetch /git_common_dir --no-tags "$GIT_HEAD_REV"
  git checkout -b test-with-docker FETCH_HEAD

  # Link in logs. Logs are on the host since that's the most important thing to
  # look at after the tests are run.
  ln -sf /logs logs

  bin/bootstrap_system.sh
  impala_environment

  # Builds Impala and loads test data.
  # Note that IMPALA-6494 prevents us from using shared library builds,
  # which are smaller and thereby speed things up. We use "-notests"
  # to avoid building backend tests, which are sizable, and
  # can be built when executing those tests. We use "-noclean" to
  # avoid deleting the log for this invocation which is in logs/,
  # and, this is a first build anyway.
  ./buildall.sh -noclean -format -testdata -notests

  # We make one exception to "-notests":
  # test_insert_parquet.py, which is used in all the end-to-end test
  # shards, depends on this binary. We build it here once,
  # instead of building it during the startup of each container running
  # a subset of E2E tests. Building it here is also a lot faster.
  make -j$(nproc) --load-average=$(nproc) parquet-reader

  # Dump current memory usage to logs, before shutting things down.
  memory_usage

  # Shut down things cleanly.
  testdata/bin/kill-all.sh

  # "Compress" HDFS data by de-duplicating blocks. As a result of
  # having three datanodes, our data load is 3x larger than it needs
  # to be. To alleviate this (to the tune of ~20GB savings), we
  # use hardlinks to link together the identical blocks. This is absolutely
  # taking advantage of an implementation detail of HDFS.
  echo "Hardlinking duplicate HDFS block data."
  set +x
  for x in $(find testdata/cluster/*/node-1/data/dfs/dn/current/ -name 'blk_*[0-9]'); do
    for n in 2 3; do
      xn=${x/node-1/node-$n}
      if [ -f $xn ]; then
        rm $xn
        ln $x $xn
      fi
    done
  done
  set -x

  # Shutting down PostgreSQL nicely speeds up it's start time for new containers.
  _pg_ctl stop

  # Clean up things we don't need to reduce image size
  find be -name '*.o' -execdir rm '{}' + # ~1.6GB

  # Clean up dangling symlinks. These (typically "cluster/cdh*-node-*")
  # may point to something inside a container that no longer exists
  # and can confuse Jenkins.
  find /logs -xtype l -execdir rm '{}' ';'

  popd
}

# Prints top 20 RSS consumers (and other, total), in megabytes Common culprits
# are Java processes without Xmx set. Since most things don't reclaim memory,
# this is a decent proxy for peak memory usage by long-lived processes.
function memory_usage() {
  (
  echo "Top 20 memory consumers (RSS in MBs)"
  sudo ps -axho rss,args | \
    sed -e 's/^ *//' | \
    sed -e 's, ,\t,' | \
    sort -nr | \
    awk -F'\t' '
    FNR < 20 { print $1/1024.0, $2; total += $1/1024.0 }
    FNR >= 20 { other+= $1/1024.0; total += $1/1024.0 }
    END {
      if (other) { print other, "-- other --" };
      print total, "-- total --"
    }'
  ) >& /logs/memory_usage.txt
}

# Runs a suite passed in as the first argument. Tightly
# coupled with Impala's run-all-tests and the suite names.
# from test-with-docker.py.
#
# Before running tests, starts up the minicluster.
function test_suite() {
  cd /home/impdev/Impala

  # These test suites are for testing.
  if [[ $1 == NOOP ]]; then
    # Sleep busily for 10 seconds.
    bash -c 'while [[ $SECONDS -lt 10 ]]; do :; done'
    return 0
  fi
  if [[ $1 == NOOP_FAIL ]]; then
    return 1
  fi
  if [[ $1 == NOOP_SLEEP_FOREVER ]]; then
    # Handy to test timeouts.
    while true; do sleep 60; done
  fi

  # Assert that we're running as impdev
  [ "$(id -un)" = impdev ]

  # Assert that /home/impdev/Impala/logs is a symlink to /logs.
  [ "$(readlink /home/impdev/Impala/logs)" = /logs ]

  boot_container
  impala_environment

  if [[ ${REBUILD_ASAN:-false} = true ]]; then
    # Note: we're not redoing data loading.
    SKIP_TOOLCHAIN_BOOTSTRAP=true ./buildall.sh -noclean -notests -asan
  fi

  # BE tests don't require the minicluster, so we can run them directly.
  if [[ $1 = BE_TEST* ]]; then
    make -j$(nproc) --load-average=$(nproc) be-test be-benchmarks
    if ! bin/run-backend-tests.sh; then
      echo "Tests $1 failed!"
      return 1
    else
      echo "Tests $1 succeeded!"
      return 0
    fi
  fi

  if [[ $1 == RAT_CHECK ]]; then
    # Runs Apache RAT (a license checker)
    git archive --prefix=rat/ -o rat-impala.zip HEAD
    wget --quiet https://archive.apache.org/dist/creadur/apache-rat-0.12/apache-rat-0.12-bin.tar.gz
    tar xzf apache-rat-0.12-bin.tar.gz
    java -jar apache-rat-0.12/apache-rat-0.12.jar -x rat-impala.zip > logs/rat.xml
    bin/check-rat-report.py bin/rat_exclude_files.txt logs/rat.xml
    return $?
  fi

  # Start the minicluster
  start_minicluster

  # By default, the JVM will use 1/4 of your OS memory for its heap size. For a
  # long-running test, this will delay GC inside of impalad's leading to
  # unnecessarily large process RSS footprints. To combat this, we
  # set a small initial heap size, and then cap it at a more reasonable
  # size. The small initial heap sizes help for daemons that do little
  # in the way of JVM work (e.g., the 2nd and 3rd impalad's).
  # Note that "test_insert_large_string" fails at 2g and 3g, so the suite that
  # includes it (EE_TEST_PARALLEL) gets additional memory.

  # Note that we avoid using TEST_START_CLUSTER_ARGS="--jvm-args=..."
  # because it gets flattened along the way if we need to provide
  # more than one Java argument. We use JAVA_TOOL_OPTIONS instead.
  JVM_HEAP_MAX_GB=2
  if [[ $1 = EE_TEST_PARALLEL ]]; then
    JVM_HEAP_MAX_GB=4
  elif [[ $1 = EE_TEST_PARALLEL_EXHAUSTIVE ]]; then
    JVM_HEAP_MAX_GB=8
  fi
  JAVA_TOOL_OPTIONS="-Xms512M -Xmx${JVM_HEAP_MAX_GB}G"

  # Similarly, bin/start-impala-cluster typically configures the memlimit
  # to be 80% of the machine memory, divided by the number of daemons.
  # If multiple containers are to be run simultaneously, this is scaled
  # down in test-with-docker.py (and further configurable with --impalad-mem-limit-bytes)
  # and passed in via $IMPALAD_MEM_LIMIT_BYTES to the container. There is a
  # relationship between the number of parallel tests that can be run by py.test and this
  # limit.
  export TEST_START_CLUSTER_ARGS="--impalad_args=--mem_limit=$IMPALAD_MEM_LIMIT_BYTES"

  export MAX_PYTEST_FAILURES=0

  # Asserting that these should are all set (to either true or false as strings).
  # This is how run-all.sh chooses between them.
  [[ $FE_TEST && $BE_TEST && $EE_TEST && $JDBC_TEST && $CLUSTER_TEST ]]

  ret=0

  # Run tests.
  (echo ">>> $1: Starting run-all-test") 2> /dev/null
  if ! time -p bash -x bin/run-all-tests.sh; then
    ret=1
    echo "Tests $1 failed!"
  else
    echo "Tests $1 succeeded!"
  fi

  # Save memory usage after tests have run but before shutting down the cluster.
  memory_usage || true

  # Oddly, I've observed bash fail to exit (and wind down the container),
  # leading to test-with-docker.py hitting a timeout. Killing the minicluster
  # daemons fixes this.
  testdata/bin/kill-all.sh || true
  return $ret
}

# It's convenient (for log files to be legible) for the container
# to have the host timezone. However, /etc/localtime is finnicky
# (see localtime(5)) and mounting it to the host /etc/localtime or
# symlinking it there doesn't always work. Instead, we expect
# $LOCALTIME_LINK_TARGET to be set to a path in /usr/share/zoneinfo.
function configure_timezone() {
  if [ -e "${LOCALTIME_LINK_TARGET}" ]; then
    ln -sf "${LOCALTIME_LINK_TARGET}" /etc/localtime
    # Only Debian-based distros have this file.
    if [ -f /etc/timezone ]; then
      echo "${LOCALTIME_LINK_TARGET}" | sed -e 's,.*zoneinfo/,,' > /etc/timezone
    fi
  else
    echo '$LOCALTIME_LINK_TARGET not configured.' 1>&2
  fi
}

# Exposes a shell, with the container booted with
# a minicluster.
function shell() {
  echo "Starting minicluster and Impala."
  # Logs is typically a symlink; remove it if so.
  rm logs || true
  mkdir -p logs
  boot_container
  impala_environment
  start_minicluster
  bin/start-impala-cluster.py
  cat <<"EOF"

==========================================================
Welcome to the Impala development environment.

The "minicluster" is running; i.e., HDFS, HBase, Hive,
etc. are running. $KUDU_MSG

To get started, perhaps run:
  impala-shell.sh -q 'select count(*) from tpcds.web_page'
==========================================================

EOF
  exec bash
}

function main() {
  set -e

  # Run given command
  CMD="$1"
  shift

  # Treat shell specialy to avoid the extra logging and | cat below.
  if [[ $CMD = "shell" ]]; then
    shell
    # shell shoud have exec'd, so if we get here, it's a failure.
    exit 1
  fi

  echo ">>> ${CMD} $@ (begin)"
  # Dump environment, for debugging
  env | grep -vE "AWS_(SECRET_)?ACCESS_KEY"
  ulimit -a
  set -x
  # The "| cat" here avoids "set -e"/errexit from exiting the
  # script right away.
  "${CMD}" "$@" | cat
  ret=${PIPESTATUS[0]}
  set +x
  echo ">>> ${CMD} $@ ($ret) (end)"
  exit $ret
}

# Run main() unless we're being sourced.
if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
  main "$@"
fi