shell脚本学习

ENTRYPOINT ["/app/bin/docker-entrypoint"]
CMD ["server"]

#!/bin/bash
set -e

celery_worker() {
  WORKERS_COUNT=${WORKERS_COUNT:-2}
  QUEUES=${QUEUES:-queries,scheduled_queries}
  WORKER_EXTRA_OPTIONS=${WORKER_EXTRA_OPTIONS:-}

  echo "Starting $WORKERS_COUNT workers for queues: $QUEUES..."
  exec /usr/local/bin/celery worker --app=redash.worker -c$WORKERS_COUNT -Q$QUEUES -linfo --max-tasks-per-child=10 -Ofair $WORKER_EXTRA_OPTIONS
}

scheduler() {
  echo "Starting RQ scheduler..."

  exec /app/manage.py rq scheduler
}

dev_scheduler() {
  echo "Starting dev RQ scheduler..."

  exec watchmedo auto-restart --directory=./redash/ --pattern=*.py --recursive -- ./manage.py rq scheduler
}

worker() {
  echo "Starting RQ worker..."

  exec /app/manage.py rq worker $QUEUES
}

dev_worker() {
  echo "Starting dev RQ worker..."

  exec watchmedo auto-restart --directory=./redash/ --pattern=*.py --recursive -- ./manage.py rq worker $QUEUES
}

dev_celery_worker() {
  WORKERS_COUNT=${WORKERS_COUNT:-2}
  QUEUES=${QUEUES:-queries,scheduled_queries}

  echo "Starting $WORKERS_COUNT workers for queues: $QUEUES..."

  exec watchmedo auto-restart --directory=./redash/ --pattern=*.py --recursive -- /usr/local/bin/celery worker --app=redash.worker -c$WORKERS_COUNT -Q$QUEUES -linfo --max-tasks-per-child=10 -Ofair
}

server() {
  # Recycle gunicorn workers every n-th request. See http://docs.gunicorn.org/en/stable/settings.html#max-requests for more details.
  MAX_REQUESTS=${MAX_REQUESTS:-1000}
  MAX_REQUESTS_JITTER=${MAX_REQUESTS_JITTER:-100}
  exec /usr/local/bin/gunicorn -b 0.0.0.0:5000 --name redash -w${REDASH_WEB_WORKERS:-4} redash.wsgi:app --max-requests $MAX_REQUESTS --max-requests-jitter $MAX_REQUESTS_JITTER
}

create_db() {
  exec /app/manage.py database create_tables
}

celery_healthcheck() {
  exec /usr/local/bin/celery inspect ping --app=redash.worker -d celery@$HOSTNAME
}

rq_healthcheck() {
  exec /app/manage.py rq healthcheck
}

help() {
  echo "Redash Docker."
  echo ""
  echo "Usage:"
  echo ""

  echo "server -- start Redash server (with gunicorn)"
  echo "celery_worker -- start Celery worker"
  echo "dev_celery_worker -- start Celery worker process which picks up code changes and reloads"
  echo "worker -- start a single RQ worker"
  echo "dev_worker -- start a single RQ worker with code reloading"
  echo "scheduler -- start an rq-scheduler instance"
  echo "dev_scheduler -- start an rq-scheduler instance with code reloading"
  echo "celery_healthcheck -- runs a Celery healthcheck. Useful for Docker's HEALTHCHECK mechanism."
  echo "rq_healthcheck -- runs a RQ healthcheck that verifies that all local workers are active. Useful for Docker's HEALTHCHECK mechanism."
  echo ""
  echo "shell -- open shell"
  echo "dev_server -- start Flask development server with debugger and auto reload"
  echo "debug -- start Flask development server with remote debugger via ptvsd"
  echo "create_db -- create database tables"
  echo "manage -- CLI to manage redash"
  echo "tests -- run tests"
}

tests() {
  export REDASH_DATABASE_URL="postgresql://postgres@postgres/tests"

  if [ $# -eq 0 ]; then
    TEST_ARGS=tests/
  else
    TEST_ARGS=$@
  fi
  exec pytest $TEST_ARGS
}

case "$1" in
  worker)
    shift
    worker
    ;;
  server)
    shift
    server
    ;;
  scheduler)
    shift
    scheduler
    ;;
  dev_scheduler)
    shift
    dev_scheduler
    ;;
  celery_worker)
    shift
    celery_worker
    ;;
  dev_celery_worker)
    shift
    dev_celery_worker
    ;;
  dev_worker)
    shift
    dev_worker
    ;;
  rq_healthcheck)
    shift
    rq_healthcheck
    ;;
  celery_healthcheck)
    shift
    celery_healthcheck
    ;;
  dev_server)
    export FLASK_DEBUG=1
    exec /app/manage.py runserver --debugger --reload -h 0.0.0.0
    ;;
  debug)
    export FLASK_DEBUG=1
    export REMOTE_DEBUG=1
    exec /app/manage.py runserver --debugger --no-reload -h 0.0.0.0
    ;;
  shell)
    exec /app/manage.py shell
    ;;
  create_db)
    create_db
    ;;
  manage)
    shift
    exec /app/manage.py $*
    ;;
  tests)
    shift
    tests $@
    ;;
  help)
    shift
    help
    ;;
  *)
    exec "$@"
    ;;
esac

[ function ] funname [()]
{
    action;
    [return int;]
}

celery_worker() {
  WORKERS_COUNT=${WORKERS_COUNT:-2}
  QUEUES=${QUEUES:-queries,scheduled_queries}
  WORKER_EXTRA_OPTIONS=${WORKER_EXTRA_OPTIONS:-}

  echo "Starting $WORKERS_COUNT workers for queues: $QUEUES..."
  exec /usr/local/bin/celery worker --app=redash.worker -c$WORKERS_COUNT -Q$QUEUES -linfo --max-tasks-per-child=10 -Ofair $WORKER_EXTRA_OPTIONS
}

# 如果WORKERS_COUNT未定义或者为空字符串，则返回默认值，否则返回WORKERS_COUNT的值
WORKERS_COUNT=${WORKERS_COUNT:-2}

$WORKERS_COUNT或者${WORKERS_COUNT}

#!/bin/bash
# author:菜鸟教程
# url:www.runoob.com

echo "Shell 传递参数实例！";
echo "执行的文件名：$0";
echo "第一个参数为：$1";
echo "第二个参数为：$2";
echo "第三个参数为：$3";
为脚本设置可执行权限，并执行脚本，输出结果如下所示：

$ chmod +x test.sh 
$ ./test.sh 1 2 3
Shell 传递参数实例！
执行的文件名：./test.sh
第一个参数为：1
第二个参数为：2
第三个参数为：3

$#	传递到脚本的参数个数
$*	以一个单字符串显示所有向脚本传递的参数。
如"$*"用「"」括起来的情况、以"$1 $2 … $n"的形式输出所有参数。
$$	脚本运行的当前进程ID号
$!	后台运行的最后一个进程的ID号
$@	与$*相同，但是使用时加引号，并在引号中返回每个参数。
如"$@"用「"」括起来的情况、以"$1" "$2" … "$n" 的形式输出所有参数。
$-	显示Shell使用的当前选项，与set命令功能相同。
$?	显示最后命令的退出状态。0表示没有错误，其他任何值表明有错误。

case "$1" in
  worker)
    shift
    worker
    ;;
  help)
    shift
    help
    ;;
  *)
    exec "$@"
    ;;
esac