Rails每当gem不使用Ubuntu和Docker组合执行重复crontab任务时

Question

我试图运行一个重复的任务，使用我的rails应用程序的何时创业板。它运行在使用Docker创建的Docker容器中，托管在Ubuntu服务器上。

我可以使用Whenever成功地创建和更新crontab文件，但它似乎没有执行任务。

当应用程序运行时，我想在后台重复执行的任务是：

rake searchkick:reindex CLASS=Property

我通常在使用‘docker-组合运行web bash’创建一个web运行容器之后，从终端成功地执行这个命令。这将重新索引我的ElasticSearch服务器，使用searchkick。

有关版本如下：

- ruby 2.7.2p137
- rails (6.0.3.6)
- elasticsearch (6.8.3)
  - elasticsearch-api (= 6.8.3)
  - elasticsearch-transport (= 6.8.3)
- searchkick (4.4.4)
  - activemodel (>= 5)
  - elasticsearch (>= 6)
  - hashie
- whenever (1.0.0)
  - chronic (>= 0.6.3)

Cron是使用Dockerfile安装的：

RUN apt-get update -qq && \
    apt-get install -y curl \
    build-essential \
    libpq-dev \
    cron \
    vim \
    nano \
    postgresql \
    postgresql-contrib \
    postgresql-client

创建容器时，Dockerfile运行脚本：

COPY entrypoint.sh /usr/bin/
RUN chmod +x /usr/bin/entrypoint.sh
ENTRYPOINT ["entrypoint.sh"]
EXPOSE 3000

脚本(entrypoint.sh)创建一个crontab文件。

#!/bin/bash
set -e

# For development check if the gems as installed, if not, then uninstall them.
if ! [ bundle check ]; then
    bundle install
fi

# Remove a potentially pre-existing server.pid for Rails.
rm -f /myapp/tmp/pids/server.pid

# Yarn - Check Files.
yarn install --check-files

# Create empty crontab file.
crontab -l | { cat; echo ""; } | crontab -

# Update crontab file using whenever command.
bundle exec whenever --set 'environment=production' --update-crontab

# Run the command - runs any arguments passed into this entrypoint file.
exec "$@"

上面的“bundle exec file set 'environment=production‘--update- crontab’命令按照下面的schedule.rb文件更新crontab文件：

set :output, "log/cron_log.log"
env :PATH, ENV['PATH']

# Reindex Property records every 3 mins.
every 3.minutes do
    rake "searchkick:reindex CLASS=Property"
end

我也试过这样做：

every 3.minutes do
    command "cd /myapp && rake searchkick:reindex CLASS=Property"
end

当我执行使用rails终端的‘docker-组合运行web bash’时，我在最后看到这个响应：

no crontab for root
[write] crontab file updated

为了检查创建是否正确，我使用“crontab -l”查看rails应用程序中的crontab文件，它显示：

# Begin Whenever generated tasks for: /myapp/config/schedule.rb at: 2021-04-24 13:07:12 +0000
PATH=/usr/local/bundle/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin

0,3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48,51,54,57 * * * * /bin/bash -l -c 'cd /myapp && RAILS_ENV=production bundle exec rake searchkick:reindex CLASS=Property --silent >> log/cron_log.log 2>&1'

# End Whenever generated tasks for: /myapp/config/schedule.rb at: 2021-04-24 13:07:12 +0000

更新:在使用cron service status和cron service start之后，myApp/log/cronlog.log中的日志显示如下：

bundler: failed to load command: rake (/usr/local/bin/rake)
Bundler::GemNotFound: Could not find rake-13.0.3 in any of the sources
  /usr/local/lib/ruby/2.7.0/bundler/spec_set.rb:86:in `block in materialize'
  /usr/local/lib/ruby/2.7.0/bundler/spec_set.rb:80:in `map!'
  /usr/local/lib/ruby/2.7.0/bundler/spec_set.rb:80:in `materialize'
  /usr/local/lib/ruby/2.7.0/bundler/definition.rb:170:in `specs'
  /usr/local/lib/ruby/2.7.0/bundler/definition.rb:237:in `specs_for'
  /usr/local/lib/ruby/2.7.0/bundler/definition.rb:226:in `requested_specs'
  /usr/local/lib/ruby/2.7.0/bundler/runtime.rb:101:in `block in definition_method'
  /usr/local/lib/ruby/2.7.0/bundler/runtime.rb:20:in `setup'
  /usr/local/lib/ruby/2.7.0/bundler.rb:149:in `setup'
  /usr/local/lib/ruby/2.7.0/bundler/setup.rb:20:in `block in <top (required)>'
  /usr/local/lib/ruby/2.7.0/bundler/ui/shell.rb:136:in `with_level'
  /usr/local/lib/ruby/2.7.0/bundler/ui/shell.rb:88:in `silence'
  /usr/local/lib/ruby/2.7.0/bundler/setup.rb:20:in `<top (required)>'
bundler: failed to load command: rake (/usr/local/bin/rake)
Bundler::GemNotFound: Could not find rake-13.0.3 in any of the sources
  /usr/local/lib/ruby/2.7.0/bundler/spec_set.rb:86:in `block in materialize'
  /usr/local/lib/ruby/2.7.0/bundler/spec_set.rb:80:in `map!'
  /usr/local/lib/ruby/2.7.0/bundler/spec_set.rb:80:in `materialize'
  /usr/local/lib/ruby/2.7.0/bundler/definition.rb:170:in `specs'
  /usr/local/lib/ruby/2.7.0/bundler/definition.rb:237:in `specs_for'
  /usr/local/lib/ruby/2.7.0/bundler/definition.rb:226:in `requested_specs'
  /usr/local/lib/ruby/2.7.0/bundler/runtime.rb:101:in `block in definition_method'
  /usr/local/lib/ruby/2.7.0/bundler/runtime.rb:20:in `setup'
  /usr/local/lib/ruby/2.7.0/bundler.rb:149:in `setup'
  /usr/local/lib/ruby/2.7.0/bundler/setup.rb:20:in `block in <top (required)>'
  /usr/local/lib/ruby/2.7.0/bundler/ui/shell.rb:136:in `with_level'
  /usr/local/lib/ruby/2.7.0/bundler/ui/shell.rb:88:in `silence'
  /usr/local/lib/ruby/2.7.0/bundler/setup.rb:20:in `<top (required)>'

因此，它似乎已经设置了crontab文件，并且cronjob正在尝试运行，但它没有找到rake-13.0.3。我要检查一下，这是否是邦德勒创业板版本的问题，而不是宝石文件中的问题。

感谢你的帮助。

Answer 1

可以在entrypoint.sh中运行cron来启动cron服务(linux)。

# Update crontab file using whenever command.
cron && bundle exec whenever --set 'environment=production' --update-crontab

schedule.rb

1. 调度不知道gems路径，因此抛出Bundler::GemNotFound错误，为了解决这个问题，可以通过在中设置ENV来避免丢失路径

set :output, "log/cron_log.log"
ENV.each { |k, v| env(k, v) }
# ...