go-crond

A cron daemon written in golang

Inspired by https://github.com/anarcher/go-cron

Using https://godoc.org/github.com/robfig/cron

Docker images

on Docker hub

• webdevops/go-crond:alpine (based on alpine)
• webdevops/go-crond:ubuntu (based on ubuntu:latest)
• webdevops/go-crond:debian (based on debian:stable-slim)
• webdevops/go-crond:{version}-alpine (based on alpine)
• webdevops/go-crond:{version}-ubuntu (based on ubuntu:latest)
• webdevops/go-crond:{version}-debian (based on debian:stable-slim)

Features

• system crontab (with username inside)
• user crontabs (without username inside)
• run-parts support
• Logging to STDOUT and STDERR (instead of sending mails)
• Keep current environment (eg. for usage in Docker containers)
• Supports Linux, MacOS, ARM/ARM64 (Rasbperry Pi and others)

Usage

Usage:
go-crond [OPTIONS] [Crontabs...]
Application Options:
-V, --version show version and exit
--dumpversion show only version number and exit
-h, --help show this help message
--default-user= Default user (default: root)
--include= Include files in directory as system crontabs (with user)
--auto Enable automatic system crontab detection
--run-parts= Execute files in directory with custom spec (like run-parts; spec-units:ns,us,s,m,h;
format:time-spec:path; eg:10s,1m,1h30m)
--run-parts-1min= Execute files in directory every beginning minute (like run-parts)
--run-parts-15min= Execute files in directory every beginning 15 minutes (like run-parts)
--run-parts-hourly= Execute files in directory every beginning hour (like run-parts)
--run-parts-daily= Execute files in directory every beginning day (like run-parts)
--run-parts-weekly= Execute files in directory every beginning week (like run-parts)
--run-parts-monthly= Execute files in directory every beginning month (like run-parts)
--allow-unprivileged Allow daemon to run as non root (unprivileged) user
--working-directory= Set the working directory for crontab commands (default: /)
-v, --verbose verbose mode [$VERBOSE]
--log.json Switch log output to json format [$LOG_JSON]
--server.bind= Server address, eg. ':8080' (/healthz and /metrics for prometheus) [$SERVER_BIND]
--server.timeout.read= Server read timeout (default: 5s) [$SERVER_TIMEOUT_READ]
--server.timeout.write= Server write timeout (default: 10s) [$SERVER_TIMEOUT_WRITE]
--server.metrics Enable prometheus metrics (do not use senstive informations in commands -> use environment
variables or files for storing these informations) [$SERVER_METRICS]
Help Options:
-h, --help Show this help message
Arguments:
Crontabs: path to crontab files

Crontab files can be added as arguments or automatic included by using eg. --include=crond-path/

Examples

Run crond with a system crontab:

go-crond examples/crontab

Run crond with user crontabs (without user in it) under specific users:

go-crond \
root:examples/crontab-root \
guest:examples/crontab-guest

Run crond with auto include of /etc/cron.d and script execution of hourly, weekly, daily and monthly:

go-crond \
--include=/etc/cron.d \
--run-parts-hourly=/etc/cron.hourly \
--run-parts-weekly=/etc/cron.weekly \
--run-parts-daily=/etc/cron.daily \
--run-parts-monthly=/etc/cron.monthly

Run crond with run-parts with custom time spec:

go-crond \
--run-parts=1m:/etc/cron.minute \
--run-parts=15m:/etc/cron.15min

Run crond with run-parts with custom time spec and different user:

go-crond \
--run-parts=1m:application:/etc/cron.minute \
--run-parts=15m:admin:/etc/cron.15min

Installation

GOCROND_VERSION=22.9.1 \
GOCRON_OS=linux \
GOCRON_ARCH=amd64 \
&& wget -O /usr/local/bin/go-crond https://github.com/webdevops/go-crond/releases/download/${GOCROND_VERSION}/go-crond.${GOCRON_OS}.${GOCRON_ARCH} \
&& chmod +x /usr/local/bin/go-crond

Docker images

Image	Description
webdevops/go-crond:latest	Latest release, binary only
webdevops/go-crond:master	Current development version in branch master

Metrics

go-crond exposes Prometheus metrics on :8080/metrics if enabled.

Metric	Description
gocrond_task_info	List of all cronjobs
gocrond_task_run_count	Counter for each executed task
gocrond_task_run_result	Last status (0=failed, 1=success) for each task
gocrond_task_run_time	Last exec time (unix timestamp) for each task
gocrond_task_run_duration	Duration of last exec