WireGuard.js: fixup lint errors

src/lib/WireGuard.js

@@ -23,7 +23,7 @@ const {
   WG_POST_UP,
   WG_PRE_DOWN,
   WG_POST_DOWN,
-  WG_INTERFACE
+  WG_INTERFACE,
 } = require('../config');
 
 module.exports = class WireGuard {
@@ -60,10 +60,10 @@ module.exports = class WireGuard {
         }
 
         await this.__saveConfig(config);
-        await Util.exec('wg-quick down ' + WG_INTERFACE).catch(() => { });
-        await Util.exec('wg-quick up ' + WG_INTERFACE).catch(err => {
-          if (err && err.message && err.message.includes('Cannot find device ' + WG_INTERFACE)) {
-            throw new Error('WireGuard exited with the error: Cannot find device ' + WG_INTERFACE + '\nThis usually means that your host\'s kernel does not support WireGuard!');
+        await Util.exec(`wg-quick down ${WG_INTERFACE}`).catch(() => { });
+        await Util.exec(`wg-quick up ${WG_INTERFACE}`).catch((err) => {
+          if (err && err.message && err.message.includes(`Cannot find device ${WG_INTERFACE}`)) {
+            throw new Error(`WireGuard exited with the error: Cannot find device ${WG_INTERFACE}\nThis usually means that your host's kernel does not support WireGuard!`);
           }
 
           throw err;
@@ -119,7 +119,7 @@ AllowedIPs = ${client.address}/32`;
     await fs.writeFile(path.join(WG_PATH, 'wg0.json'), JSON.stringify(config, false, 2), {
       mode: 0o660,
     });
-    await fs.writeFile(path.join(WG_PATH, WG_INTERFACE + '.conf'), result, {
+    await fs.writeFile(path.join(WG_PATH, `${WG_INTERFACE}.conf`), result, {
       mode: 0o600,
     });
     debug('Config saved.');
@@ -127,7 +127,7 @@ AllowedIPs = ${client.address}/32`;
 
   async __syncConfig() {
     debug('Config syncing...');
-    await Util.exec('wg syncconf ' + WG_INTERFACE + ' <(wg-quick strip ' + WG_INTERFACE + ')');
+    await Util.exec(`wg syncconf ${WG_INTERFACE} <(wg-quick strip ${WG_INTERFACE})`);
     debug('Config synced.');
   }
 
@@ -150,7 +150,7 @@ AllowedIPs = ${client.address}/32`;
     }));
 
     // Loop WireGuard status
-    const dump = await Util.exec('wg show ' + WG_INTERFACE + ' dump', {
+    const dump = await Util.exec(`wg show ${WG_INTERFACE} dump`, {
       log: false,
     });
     dump