git commit hook using node to ensure commit message follows a convention

commit-msg

#!/usr/bin/env node

// NOTES:
// 1. This is one of the three implementation, if you do not have 'node' installed, there is a 'python' and a 'scala' counterpart.
// 2. To use this file, place it in .git/hooks/ in your repository.
// 3. You can also use this script with the 'husky' npm module.

var fs = require("fs");
console.log("INFO: Validating git commit message.......");
var msg = fs.readFileSync(process.argv[2] || process.env.GIT_PARAMS || process.env.HUSKY_GIT_PARAMS, "utf8").replace(/\n/g, " ").substr(0, 50);
var matchTest = /^(([A-Z]+-?\d+|Adhoc)\: (.+: )?(Added|Removed|BugFix|Modified|Feature|Merged|Refactored|Release): (.+){15,})$/g.test(msg);
var exitCode = matchTest?0:1;

if (exitCode === 0) {
	console.log("SUCCESS: Commit ACCEPTED.");
} else {
	console.log("ERROR: Commit REJECTED. REASON: Your commit message: '" + msg + "' does not follow the commit message convention.");
	console.log("Convention: '[JIRAID]: [Optional clientId]: [One Primary Change Type: Added|Removed|BugFix|Modified|Feature|Merged|Refactored|Release]: [Message describing the change. If absolutely necessary, you can add multiple Change types here.]");
	console.log("Sample: IT-123: Added: git hook to validate commit message.");
}
process.exit(exitCode);