runmon

Run a command and perform tasks based on that command's output.

This is a Node.js CLI tool for running a command, monitoring its output, and then running one or more other tasks every time a line of the command's output matches a pattern.

Installation

npm install runmon --save-dev

Usage

runmon [options] <command> <pattern> <task> [<task> ...]

Runs <command>, and when <pattern> appears in a line of the command's stdout, runs the <task>(s).

options:
	--startup-match-timeout=<milliseconds>
		Run the task(s) if <milliseconds> from command startup elapses with no output matching the pattern.

NOTES: The pattern can be a regular expression, e.g. "matchme$" matches only on a line where "matchme" is at the end. Pattern matching is performed on a line-by-line basis; consequently, you cannot match text across lines. The tasks are run every time a line of stdout matches the pattern; however, if a task is already running, another instance of that task is NOT started.

Example

To start nodemon after 'tsc -w' is done compiling (assumes you have a script labeled nodemon):

In your package.json scripts section:

"dev": "runmon \"tsc -w\" \"Found 0 errors.\" \"npm run nodemon\""

Release History

• 0.2.2
  • Corrected version number in package-lock.json. Minor tweak to head comment in index.js.
• 0.2.1
  • Fixed issue with premature termination of the primary task. Minor refactoring to address cross-platform testing issues.
• 0.2.0
  • Changed --startup-match-timeout option to be of the form option=value. Added tests to the module. Other minor refactorings.
• 0.1.0
  • Initial release

Why

The motivation for creating this tool came out of my search for a reliable cross-platform way to order the execution of tasks around the Typescript compiler running in watch mode (tsc -w). Specifically, I wanted to ensure I could run tasks after, and only after, the compiler finished compiling. There are, no doubt, other ways to solve this problem, but I wanted something simple that didn't add too much to a project's dev dependencies.

For reference: https://github.com/Microsoft/TypeScript/issues/12996

Meta

Dan Ziegelbein – [email protected]

Distributed under the ISC license. See LICENSE for more information.

https://github.com/dziegelbein/runmon