jr

jr is a command-line tool for running periodic tests and sending the results to various outputs. It is designed to be extensible through a simple plugin system.

Configuration

jr is configured through the jr.conf file. Each line in this file defines a test to be run, with the following format:

name::seconds::test::arguments

• name: A unique name for the test.
• seconds: The interval in seconds at which to run the test.
• test: The name of the worker plugin to execute.
• arguments: A string of arguments to pass to the worker plugin.

Example jr.conf:

load_avg::30::load_avg::mordor
check_session_endpoint::300::check_url::https://www.clinique.com//rest/api/v1/user/session?brand=2&region=0
saltogrande_gefs_00::6::timethis::sleep 3

Usage

To run jr, simply execute the binary:

./jr

jr also accepts command-line arguments to override or supplement the configuration file.

• --every <SECONDS>: Overrides the interval for all tests.
• --once: Runs all tests once and then exits.
• --name <NAME>: Runs only the test with the specified name.

Plugins

jr has two types of plugins:

• Worker Plugins: These perform the actual tests, such as checking a URL, measuring CPU load, or timing a command.
• Output Plugins: These take the results from the worker plugins and send them to different destinations, such as standard output, Graphite, or a web service.

Available Worker Plugins

• check_url: Checks if a URL is reachable.
• df: Checks disk usage.
• load_avg: Checks the system load average.
• ping: Pings a host to check for reachability.
• query_api: Queries a JSON API and extracts a value.
• runthis: Executes a shell command.
• timethis: Measures the execution time of a shell command.