✨

src/utils/dependencyChecker.ts

+import Logger from './logger';
+import { exec } from 'shelljs';
+
+export default class DependencyChecker {
+	logger: Logger;
+
+	constructor() {
+		this.logger = new Logger('Deps');
+	}
+
+	checkAll(): void {
+		this.logger.info('Checking started');
+		this.check('Node.js', 'node -v', x => x.match(/^v(.*)\r?\n$/));
+		this.check('npm', 'npm -v', x => x.match(/^(.*)\r?\n$/));
+		this.check('MongoDB', 'mongo --version', x => x.match(/^MongoDB shell version: (.*)\r?\n$/));
+		this.check('Redis', 'redis-server --version', x => x.match(/v=([0-9\.]*)/));
+		this.logger.info('Checking finished');
+	}
+
+	check(serviceName: string, command: string, transform: (x: string) => RegExpMatchArray): void {
+		const code = {
+			success: 0,
+			notFound: 127
+		};
+		const x = exec(command, { silent: true }) as any;
+		if (x.code === code.success) {
+			let ver = transform(x.stdout);
+			if (ver != null) {
+				this.logger.info(`${serviceName} ${ver[1]} found`);
+			} else {
+				this.logger.warn(`${serviceName} not found`);
+				this.logger.warn(`Regexp used for version check of ${serviceName} is probably messed up`);
+			}
+		} else if (x.code === code.notFound) {
+			this.logger.warn(`${serviceName} not found`);
+		}
+	}
+}