redis - 将 Celery 作为守护进程运行不会使用 Redis 代理

Question

我有

celery==3.1.23
Django==1.9.1
redis==2.10.5
ii  redis-server       2:2.8.19-3     amd64          Persistent key-value database with networ
ii  redis-tools        2:2.8.19-3     amd64          Persistent key-value database with networ

我的配置设置有几行

# Celery
BROKER_URL = 'redis://127.0.0.1:6379/0'
BROKER_TRANSPORT = 'redis'
# start worker with '$ celery -A intro worker -l debug'

我的配置文件celery.py(标准做法是这样命名，但在我看来很困惑)是

from __future__ import absolute_import

import os
import django

from celery import Celery
from django.conf import settings

os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'intro.settings')
django.setup()

app = Celery('intro')

app.config_from_object('django.conf:settings')
app.autodiscover_tasks(lambda: settings.INSTALLED_APPS)

配置文件/etc/default/celeryd(同样令人困惑的命名)是

# copy this file to /etc/default/celeryd
CELERYD_NODES="w1 w2 w3"
VIRTUAL_ENV_PATH="/srv/intro/bin"

# JRT
CELERY_BIN="${VIRTUAL_ENV_PATH}/celery"

# Where to chdir at start.
CELERYD_CHDIR="/srv/intro/intro"

# Python interpreter from environment.
ENV_PYTHON="$VIRTUAL_ENV_PATH/python"

# How to call "manage.py celeryd_multi"
CELERYD_MULTI="$ENV_PYTHON $CELERYD_CHDIR/manage.py celeryd_multi"

# How to call "manage.py celeryctl"
CELERYCTL="$ENV_PYTHON $CELERYD_CHDIR/manage.py celeryctl"

# Extra arguments to celeryd NOTE --beat is vital, otherwise scheduler
# will not run
CELERYD_OPTS="--concurrency=1 --beat"

# %n will be replaced with the nodename.
CELERYD_LOG_FILE="/var/log/celery/%n.log"
CELERYD_PID_FILE="/var/run/celery/%n.pid"

# Workers should run as an unprivileged user.
CELERYD_USER="jimmy"
CELERYD_GROUP="jimmy"

# Name of the projects settings module.
export DJANGO_SETTINGS_MODULE="intro.settings"

#CELERY_BROKER_URL = 'redis://127.0.0.1:6379/0'
#export DJANGO_SETTINGS_MODULE="settings"

#CELERYD_MULTI="/home/webapps/.virtualenvs/crowdstaff/bin/django-admin.py celeryd_detach"

我的/etc/init.d/celeryd 文件是

#!/bin/sh -e
VERSION=10.1
echo "celery init v${VERSION}."
if [ $(id -u) -ne 0 ]; then
    echo "Error: This program can only be used by the root user."
    echo "       Unprivileged users must use the 'celery multi' utility, "
    echo "       or 'celery worker --detach'."
    exit 1
fi


# Can be a runlevel symlink (e.g. S02celeryd)
if [ -L "$0" ]; then
    SCRIPT_FILE=$(readlink "$0")
else
    SCRIPT_FILE="$0"
fi
SCRIPT_NAME="$(basename "$SCRIPT_FILE")"

DEFAULT_USER="celery"
DEFAULT_PID_FILE="/var/run/celery/%n.pid"
DEFAULT_LOG_FILE="/var/log/celery/%n.log"
DEFAULT_LOG_LEVEL="INFO"
DEFAULT_NODES="celery"
DEFAULT_CELERYD="-m celery worker --detach"

CELERY_DEFAULTS=${CELERY_DEFAULTS:-"/etc/default/${SCRIPT_NAME}"}

# Make sure executable configuration script is owned by root
_config_sanity() {
    local path="$1"
    local owner=$(ls -ld "$path" | awk '{print $3}')
    local iwgrp=$(ls -ld "$path" | cut -b 6)
    local iwoth=$(ls -ld "$path" | cut -b 9)

    if [ "$(id -u $owner)" != "0" ]; then
        echo "Error: Config script '$path' must be owned by root!"
        echo
        echo "Resolution:"
        echo "Review the file carefully and make sure it has not been "
        echo "modified with mailicious intent.  When sure the "
        echo "script is safe to execute with superuser privileges "
        echo "you can change ownership of the script:"
        echo "    $ sudo chown root '$path'"
        exit 1
    fi

    if [ "$iwoth" != "-" ]; then  # S_IWOTH
        echo "Error: Config script '$path' cannot be writable by others!"
        echo
        echo "Resolution:"
        echo "Review the file carefully and make sure it has not been "
        echo "modified with malicious intent.  When sure the "
        echo "script is safe to execute with superuser privileges "
        echo "you can change the scripts permissions:"
        echo "    $ sudo chmod 640 '$path'"
        exit 1
    fi
    if [ "$iwgrp" != "-" ]; then  # S_IWGRP
        echo "Error: Config script '$path' cannot be writable by group!"
        echo
        echo "Resolution:"
        echo "Review the file carefully and make sure it has not been "
        echo "modified with malicious intent.  When sure the "
        echo "script is safe to execute with superuser privileges "
        echo "you can change the scripts permissions:"
        echo "    $ sudo chmod 640 '$path'"
        exit 1
    fi
}

if [ -f "$CELERY_DEFAULTS" ]; then
    _config_sanity "$CELERY_DEFAULTS"
    echo "Using config script: $CELERY_DEFAULTS"
    . "$CELERY_DEFAULTS"
fi

# Sets --app argument for CELERY_BIN
CELERY_APP_ARG=""
if [ ! -z "$CELERY_APP" ]; then
    CELERY_APP_ARG="--app=$CELERY_APP"
fi

CELERYD_USER=${CELERYD_USER:-$DEFAULT_USER}

# Set CELERY_CREATE_DIRS to always create log/pid dirs.
CELERY_CREATE_DIRS=${CELERY_CREATE_DIRS:-0}
CELERY_CREATE_RUNDIR=$CELERY_CREATE_DIRS
CELERY_CREATE_LOGDIR=$CELERY_CREATE_DIRS
if [ -z "$CELERYD_PID_FILE" ]; then
    CELERYD_PID_FILE="$DEFAULT_PID_FILE"
    CELERY_CREATE_RUNDIR=1
fi
if [ -z "$CELERYD_LOG_FILE" ]; then
    CELERYD_LOG_FILE="$DEFAULT_LOG_FILE"
    CELERY_CREATE_LOGDIR=1
fi

CELERYD_LOG_LEVEL=${CELERYD_LOG_LEVEL:-${CELERYD_LOGLEVEL:-$DEFAULT_LOG_LEVEL}}
CELERY_BIN=${CELERY_BIN:-"celery"}
CELERYD_MULTI=${CELERYD_MULTI:-"$CELERY_BIN multi"}
CELERYD_NODES=${CELERYD_NODES:-$DEFAULT_NODES}

export CELERY_LOADER

if [ -n "$2" ]; then
    CELERYD_OPTS="$CELERYD_OPTS $2"
fi

CELERYD_LOG_DIR=`dirname $CELERYD_LOG_FILE`
CELERYD_PID_DIR=`dirname $CELERYD_PID_FILE`

# Extra start-stop-daemon options, like user/group.
if [ -n "$CELERYD_CHDIR" ]; then
    DAEMON_OPTS="$DAEMON_OPTS --workdir=$CELERYD_CHDIR"
fi


check_dev_null() {
    if [ ! -c /dev/null ]; then
        echo "/dev/null is not a character device!"
        exit 75  # EX_TEMPFAIL
    fi
}


maybe_die() {
    if [ $? -ne 0 ]; then
        echo "Exiting: $* (errno $?)"
        exit 77  # EX_NOPERM
    fi
}

create_default_dir() {
    if [ ! -d "$1" ]; then
        echo "- Creating default directory: '$1'"
        mkdir -p "$1"
        maybe_die "Couldn't create directory $1"
        echo "- Changing permissions of '$1' to 02755"
        chmod 02755 "$1"
        maybe_die "Couldn't change permissions for $1"
        if [ -n "$CELERYD_USER" ]; then
            echo "- Changing owner of '$1' to '$CELERYD_USER'"
            chown "$CELERYD_USER" "$1"
            maybe_die "Couldn't change owner of $1"
        fi
        if [ -n "$CELERYD_GROUP" ]; then
            echo "- Changing group of '$1' to '$CELERYD_GROUP'"
            chgrp "$CELERYD_GROUP" "$1"
            maybe_die "Couldn't change group of $1"
        fi
    fi
}


check_paths() {
    if [ $CELERY_CREATE_LOGDIR -eq 1 ]; then
        create_default_dir "$CELERYD_LOG_DIR"
    fi
    if [ $CELERY_CREATE_RUNDIR -eq 1 ]; then
        create_default_dir "$CELERYD_PID_DIR"
    fi
}

create_paths() {
    create_default_dir "$CELERYD_LOG_DIR"
    create_default_dir "$CELERYD_PID_DIR"
}

export PATH="${PATH:+$PATH:}/usr/sbin:/sbin"


_get_pidfiles () {
    # note: multi < 3.1.14 output to stderr, not stdout, hence the redirect.
    ${CELERYD_MULTI} expand "${CELERYD_PID_FILE}" ${CELERYD_NODES} 2>&1
}


_get_pids() {
    found_pids=0
    my_exitcode=0

    for pidfile in $(_get_pidfiles); do
        local pid=`cat "$pidfile"`
        local cleaned_pid=`echo "$pid" | sed -e 's/[^0-9]//g'`
        if [ -z "$pid" ] || [ "$cleaned_pid" != "$pid" ]; then
            echo "bad pid file ($pidfile)"
            one_failed=true
            my_exitcode=1
        else
            found_pids=1
            echo "$pid"
        fi

    if [ $found_pids -eq 0 ]; then
        echo "${SCRIPT_NAME}: All nodes down"
        exit $my_exitcode
    fi
    done
}


_chuid () {
    su "$CELERYD_USER" -c "$CELERYD_MULTI $*"
}


start_workers () {
    if [ ! -z "$CELERYD_ULIMIT" ]; then
        ulimit $CELERYD_ULIMIT
    fi
    _chuid $* start $CELERYD_NODES $DAEMON_OPTS     \
                 --pidfile="$CELERYD_PID_FILE"      \
                 --logfile="$CELERYD_LOG_FILE"      \
                 --loglevel="$CELERYD_LOG_LEVEL"    \
                 $CELERY_APP_ARG                    \
                 $CELERYD_OPTS
}


dryrun () {
    (C_FAKEFORK=1 start_workers --verbose)
}


stop_workers () {
    _chuid stopwait $CELERYD_NODES --pidfile="$CELERYD_PID_FILE"
}


restart_workers () {
    _chuid restart $CELERYD_NODES $DAEMON_OPTS      \
                   --pidfile="$CELERYD_PID_FILE"    \
                   --logfile="$CELERYD_LOG_FILE"    \
                   --loglevel="$CELERYD_LOG_LEVEL"  \
                   $CELERY_APP_ARG                  \
                   $CELERYD_OPTS
}


kill_workers() {
    _chuid kill $CELERYD_NODES --pidfile="$CELERYD_PID_FILE"
}


restart_workers_graceful () {
    echo "WARNING: Use with caution in production"
    echo "The workers will attempt to restart, but they may not be able to."
    local worker_pids=
    worker_pids=`_get_pids`
    [ "$one_failed" ] && exit 1

    for worker_pid in $worker_pids; do
        local failed=
        kill -HUP $worker_pid 2> /dev/null || failed=true
        if [ "$failed" ]; then
            echo "${SCRIPT_NAME} worker (pid $worker_pid) could not be restarted"
            one_failed=true
        else
            echo "${SCRIPT_NAME} worker (pid $worker_pid) received SIGHUP"
        fi
    done

    [ "$one_failed" ] && exit 1 || exit 0
}


check_status () {
    my_exitcode=0
    found_pids=0

    local one_failed=
    for pidfile in $(_get_pidfiles); do
        if [ ! -r $pidfile ]; then
            echo "${SCRIPT_NAME} down: no pidfiles found"
            one_failed=true
            break
        fi

        local node=`basename "$pidfile" .pid`
        local pid=`cat "$pidfile"`
        local cleaned_pid=`echo "$pid" | sed -e 's/[^0-9]//g'`
        if [ -z "$pid" ] || [ "$cleaned_pid" != "$pid" ]; then
            echo "bad pid file ($pidfile)"
            one_failed=true
        else
            local failed=
            kill -0 $pid 2> /dev/null || failed=true
            if [ "$failed" ]; then
                echo "${SCRIPT_NAME} (node $node) (pid $pid) is down, but pidfile exists!"
                one_failed=true
            else
                echo "${SCRIPT_NAME} (node $node) (pid $pid) is up..."
            fi
        fi
    done

    [ "$one_failed" ] && exit 1 || exit 0
}


case "$1" in
    start)
        check_dev_null
        check_paths
        start_workers
    ;;

    stop)
        check_dev_null
        check_paths
        stop_workers
    ;;

    reload|force-reload)
        echo "Use restart"
    ;;

    status)
        check_status
    ;;

    restart)
        check_dev_null
        check_paths
        restart_workers
    ;;

    graceful)
        check_dev_null
        restart_workers_graceful
    ;;

    kill)
        check_dev_null
        kill_workers
    ;;

    dryrun)
        check_dev_null
        dryrun
    ;;

    try-restart)
        check_dev_null
        check_paths
        restart_workers
    ;;

    create-paths)
        check_dev_null
        create_paths
    ;;

    check-paths)
        check_dev_null
        check_paths
    ;;

    *)
        echo "Usage: /etc/init.d/${SCRIPT_NAME} {start|stop|restart|graceful|kill|dryrun|create-paths}"
        exit 64  # EX_USAGE
    ;;
esac

exit 0

它很旧，很长，似乎不包含任何我可以更改以影响使用的代理，除了默认值脚本 CELERY_DEFAULTS=/etc/default/celeryd 的位置(再次混淆名称).我承认我在没有完全理解的情况下很好地复制和粘贴了这个脚本，尽管我知道 init.d 脚本是如何工作的。

当我运行 /etc/init.d/celeryd start 工作人员启动，但忽略指向我的 redis 服务器的 BROKER django 设置，并尝试读取 RabbitMQ。日志文件/var/log/celery/w1.log

[2016-11-30 23:44:51,873: ERROR/MainProcess] consumer: Cannot connect to amqp://guest:**@127.0.0.1:5672//: [Errno 111] Connection refused.

所以 celery 正在尝试使用 RabbitMQ，而不是 Redis。还有其他帖子在 Stack overflow 上提示同样的问题，但没有一个得到解决(据我所知)。我把 djcelery 放在已安装的应用程序中，因为它似乎使 celeryd_multi 管理命令可用，但我不想使用 celery beat，文档说这不再是必需的。我设置了自己的队列来运行管理命令，过去我在设置 celerybeat 时遇到了太多问题。

我通过运行 sudo -u jimmy/srv/intro/bin/celery -A intro worker & 使它正常工作，这有效并使用了正确的 Redis 队列(有谁知道为什么它称为代理？)，但不会在服务器电源循环时重新启动，不会写入日志文件，我只是觉得这不是运行 celery worker 的干净方法。

我真的不想使用/etc/init.d 脚本，因为这是做事的老方法，并且作为 upstart 运行来代替它，现在 systemd 是执行此操作的支持方式(如果我错了，请纠正我)。官方文档上没有提到这些方法 http://docs.celeryproject.org/en/v4.0.0/userguide/daemonizing.html#init-script-celeryd这让我觉得不再支持 celery ，也许有更好的维护方式来做到这一点。奇怪的是它没有被内置到核心中。

我确实找到了这个 https://github.com/celery/celery/blob/3.1/extra/supervisord/supervisord.conf但是配置文件中没有提到代理，我怀疑这对我使用 Redis 有帮助。

我如何让 Celery 作为守护进程运行以在重启时自动启动，并将 Redis 用作消息队列，或者是我使用 Celery 在 Django 中异步运行函数以使用 RabbitMQ 消息队列的唯一方法？

Answer 1

为确保 celery 加载正确的代理，将代理参数添加到 Celery 类。

app = Celery('intro', broker=settings.BROKER_URL)

引用: http://docs.celeryproject.org/en/latest/getting-started/first-steps-with-celery.html#application