Scutwork ++++++++

A replacement for cron, primarily intended for use in containers.

- `Python`_ 3.5.x
- `click`_
- `crontab`_
- `pytimeparse`_

.. _Python: http://www.python.org/ .. _click: http://click.pocoo.org/ .. _crontab: http://click.pocoo.org/ .. _pytimeparse: http://click.pocoo.org/

.. code-block:: sh

$ scutwork jobs.json

-v, --verbose Verbose output. Environment variable: SCUTWORK_VERBOSE

--localtime Use local time for log timestamps. The default is to use UTC timestamps. Environment variable: SCUTWORK_LOCALTIME

--logformat The log format. See the relevant <https://docs.python.org/3/library/logging.html#logrecord-attributes>_ section in the python manual. Environment variable: SCUTWORK_LOGFORMAT

--logconfig Configure logging using the supplied configuration file. See python manual <https://docs.python.org/3/library/logging.config.html>_. The name of the logger for the jobs is job. Environment variable: SCUTWORK_LOGCONFIG

--help Show the help message.

All jobs inherit their environment from the main scutwork process. If SHELL is not set it will be set to /bin/sh. If PATH is not set it will be set to /usr/bin;/bin. The environment for each job can be customized using the env job option (see below).

As opposed to cron, scutwork will only log the output of a job if the exit status is not 0 or there was some error output. If the processes exited with a status other than 0 the stderr output is logged and if there is no stderr output the stdout output will be logged, if any. Note that process output is temporary stored on disk so it's advisable to avoid producing large amounts of output. In short, scutwork expects jobs to behave well and exit with a non-zero status on error and only produce error output if there's an error or other situation that warrants attention.

Configuration can be either a JSON file or a YAML file, the latter requiring that PyYAML is installed.

name The name of the job

cmd The command to run. Unless shell is set to true this should be an array. If shell is set to true it should be a string.

when When to run this job. Depending on the format this is either a crontab-style time specification (5 * * * *) or a pytimeparse-style interval (15s). The default for crontab is * * * * *.

format Format of the when property. Can be either crontab or interval. Default is crontab.

cwd The working directory.

shell If set to true the command will be run in a shell. Default is false.

env This is an object with environment variable names and values.

ignore_stderr Normally scutwork will log any output to stderr but if you have a process that misbehaves and produces errant stderr output you can ignore it by setting this to true. This option has no effect if the process exits with non-zero status.

.. code-block:: json

[
    {
        "name": "This will run every minute",
        "cmd": [
            "/bin/sleep",
            "15"
        ]
    },
    {
        "name": "This will run every 15 seconds",
        "cmd": ["/bin/date"],
        "when": "15s",
        "format": "interval"
    },
    {
        "name": "This will run 5 minutes after midnight with working dir /var/run",
        "cmd": ["/bin/date"],
        "when": "5 0 * * *",
        "cwd": "/var/run"
    },
    {
        "name": "This will run in a shell",
        "cmd": "/bin/date || wc -l",
        "shell": true
    },
    {
        "name": "Run with some env variables",
        "cmd": ["/bin/date"],
        "env": {
            "USERNAME": "kermit",
            "TZ": "Asia/Manila"
        }
    }
]

YAML files work the same way.

.. code-block:: yaml

---
    - name: Some job
      cmd:
          - /bin/date
      when: 5 * * * *
      cwd: /var/run
      env:
          TZ: Asia/Manila
    - name: Other job
      cmd: ["/bin/sleep"]