Lock and unlock OSX from http request.

nodejs-unlock

var applescript = require('applescript');
var http = require('http');
require('shelljs/global');

var script =
	'tell application "System Events"\n\
		if name of every process contains "ScreenSaverEngine" then \n\
			tell application "ScreenSaverEngine"\n\
				quit\n\
			end tell\n\
			delay 0.2\n\
 		else \n\
		tell application "Terminal"\n\
			do shell script "caffeinate -u -t 1"\n\
		end tell\n\
		delay 0.5\n\
		end if\n\
		keystroke "YOUR_PASSWORD"\n\
		keystroke return\n\
		get computer name of (system info)\n\
	end tell';

function onRequest(req, res) {
	if (req.url == '/unlock') {
		if (!exec('python -c \'import sys,Quartz; d=Quartz.CGSessionCopyCurrentDictionary(); sys.exit(d and d.get("CGSSessionScreenIsLocked", 0) == 0 and d.get("kCGSSessionOnConsoleKey", 0) == 1)\'')['code']){
			applescript.execString(script, function(err, rtn) {
				if (err) console.error(err);
				res.writeHead(200, { 'Content-Type': 'text/plain' });
				res.write( err ? 'something went wrong while unlocking' : 'unlocked ' + rtn );
				res.end();
			});
		} else {
			res.writeHead(200, { 'Content-Type': 'text/plain' });
			res.write('OSX isn\'t currently locked.');
			res.end();
		}
	} else if (req.url == '/lock') {
		applescript.execString('do shell script "open /System/Library/Frameworks/ScreenSaver.framework/Versions/A/Resources/ScreenSaverEngine.app"');
	} else {
		console.log('WHAT?');
		res.writeHead(200, { 'Content-Type': 'text/plain' });
		res.write('WHAT?');
		res.end();
	}
}

http.createServer(onRequest).listen(9091);

To use this run the following line in terminal.
You must have node.js or a fork like io.js installed.

curl -o app.js https://gist.githubusercontent.com/OmgImAlexis/1519cc5fa1ac392fb2d1/raw/ce73a885e976e510e35f67af4629d3ad352ea233/nodejs-unlock && npm install -g nodemon && npm install shelljs && npm install applescript && clear && echo 'Install done'

Make sure to replace YOUR_PASSWORD in app.js with your own password and then run forever start app.js, to stop the process use forever stop 0.

No reason to go to shell from applescript to activate screensaver.
'tell application "System Events"\n
start current screen saver\n
end tell'

And thanks for the solution around lock screen detection! 😄