yurake/k8s-3tier-webapp

#!/bin/bash
set -e

### COPY FROM
### https://github.com/docker-library/cassandra/blob/master/4.0/docker-entrypoint.sh

# first arg is `-f` or `--some-option`
# or there are no args
if [ "$#" -eq 0 ] || [ "${1#-}" != "$1" ]; then
  set -- cassandra -f "$@"
fi

# allow the container to be started with `--user`
# shellcheck disable=SC2166
if [ "$1" = 'cassandra' -a "$(id -u)" = '0' ]; then
  find "$CASSANDRA_CONF" /var/lib/cassandra /var/log/cassandra \
    \! -user cassandra -exec chown cassandra '{}' +
  # shellcheck disable=SC2128
  exec gosu cassandra "$BASH_SOURCE" "$@"
fi

_ip_address() {
  # scrape the first non-localhost IP address of the container
  # in Swarm Mode, we often get two IPs -- the container IP, and the (shared) VIP, and the container IP should always be first
  ip address | awk '
        $1 == "inet" && $NF != "lo" {
            gsub(/\/.+$/, "", $2)
            print $2
            exit
        }
    '
}

# "sed -i", but without "mv" (which doesn't work on a bind-mounted file, for example)
_sed-in-place() {
  local filename="$1"
  shift
  local tempFile
  tempFile="$(mktemp)"
  sed "$@" "$filename" >"$tempFile"
  cat "$tempFile" >"$filename"
  rm "$tempFile"
}

if [ "$1" = 'cassandra' ]; then
  # shellcheck disable=SC2223
  : ${CASSANDRA_RPC_ADDRESS='0.0.0.0'}

  # shellcheck disable=SC2223
  : ${CASSANDRA_LISTEN_ADDRESS='auto'}
  if [ "$CASSANDRA_LISTEN_ADDRESS" = 'auto' ]; then
    CASSANDRA_LISTEN_ADDRESS="$(_ip_address)"
  fi

  # shellcheck disable=SC2223
  : ${CASSANDRA_BROADCAST_ADDRESS="$CASSANDRA_LISTEN_ADDRESS"}

  if [ "$CASSANDRA_BROADCAST_ADDRESS" = 'auto' ]; then
    CASSANDRA_BROADCAST_ADDRESS="$(_ip_address)"
  fi
  # shellcheck disable=SC2223
  : ${CASSANDRA_BROADCAST_RPC_ADDRESS:=$CASSANDRA_BROADCAST_ADDRESS}

  if [ -n "${CASSANDRA_NAME:+1}" ]; then
    # shellcheck disable=SC2223
    : ${CASSANDRA_SEEDS:="cassandra"}
  fi
  : ${CASSANDRA_SEEDS:="$CASSANDRA_BROADCAST_ADDRESS"}

  _sed-in-place "$CASSANDRA_CONF/cassandra.yaml" \
    -r 's/(- seeds:).*/\1 "'"$CASSANDRA_SEEDS"'"/'

  for yaml in \
    broadcast_address \
    broadcast_rpc_address \
    cluster_name \
    endpoint_snitch \
    listen_address \
    num_tokens \
    rpc_address \
    start_rpc; do
    var="CASSANDRA_${yaml^^}"
    val="${!var}"
    if [ "$val" ]; then
      _sed-in-place "$CASSANDRA_CONF/cassandra.yaml" \
        -r 's/^(# )?('"$yaml"':).*/\2 '"$val"'/'
    fi
  done

  for rackdc in dc rack; do
    var="CASSANDRA_${rackdc^^}"
    val="${!var}"
    if [ "$val" ]; then
      _sed-in-place "$CASSANDRA_CONF/cassandra-rackdc.properties" \
        -r 's/^('"$rackdc"'=).*/\1 '"$val"'/'
    fi
  done
fi

### ADD FROM
### https://stackoverflow.com/questions/32254497/create-keyspace-automatically-inside-docker-container-with-cassandra

for f in docker-entrypoint-initdb.d/*; do
  case "$f" in
  *.sh)
    echo "$0: running $f"
    # shellcheck disable=SC1090
    . "$f"
    ;;
  *.cql) echo "$0: running $f" && until cqlsh -f "$f"; do
    echo >&2 "Cassandra is unavailable - sleeping"
    sleep 2
  done &;;
  *) echo "$0: ignoring $f" ;;
  esac
  echo
done

exec "$@"