feat: verify config files exist on startup

lolisafe.js

@@ -1,3 +1,15 @@
+const logger = require('./logger')
+
+// Stray errors and exceptions capturers
+process.on('uncaughtException', error => {
+  logger.error(error, { prefix: 'Uncaught Exception: ' })
+})
+
+process.on('unhandledRejection', error => {
+  logger.error(error, { prefix: 'Unhandled Rejection (Promise): ' })
+})
+
+// Require libraries
 const bodyParser = require('body-parser')
 const ClamScan = require('clamscan')
 const contentDisposition = require('content-disposition')
@@ -8,19 +20,27 @@ const path = require('path')
 const RateLimit = require('express-rate-limit')
 const readline = require('readline')
 const serveStatic = require('serve-static')
+const { accessSync, constants } = require('fs')
+
+// Check required config files
+const configFiles = ['config.js', 'views/_globals.njk']
+for (const file of configFiles) {
+  try {
+    accessSync(file, constants.R_OK)
+  } catch (error) {
+    logger.error(`Config file '${file}' cannot be found or read.`)
+    logger.error('Please copy the provided sample file and modify it according to your needs.')
+    process.exit(1)
+  }
+}
+
+// Require config files
 const config = require('./config')
-const logger = require('./logger')
 const versions = require('./src/versions')
-const safe = express()
 
+// lolisafe
 logger.log('Starting lolisafe\u2026')
-
-process.on('uncaughtException', error => {
-  logger.error(error, { prefix: 'Uncaught Exception: ' })
-})
-process.on('unhandledRejection', error => {
-  logger.error(error, { prefix: 'Unhandled Rejection (Promise): ' })
-})
+const safe = express()
 
 const paths = require('./controllers/pathsController')
 const utils = require('./controllers/utilsController')