add generate key script

scripts/generate_key.js

@@ -0,0 +1,46 @@
+const crypto = require('crypto');
+const path = require('path');
+const args = require('args-parser')(process.argv);
+const fs = require('fs');
+
+let key = crypto.randomBytes(256).toString('base64');
+let dotenv = path.resolve('.env');
+
+if (args['help']) {
+    console.log(path.basename(__filename) + ' [--key-only] [--env|-e] [--set-key] [--dry-run]');
+    console.log('\n' + 
+        '  --help: Display this help\n' +
+        '  --key-only: Generate key only and put it in stdout\n' + 
+        '  --env -e: Specify an env file\n' +
+        '  --set-key: Specify your key\n' +
+        '  --dry-run: Don\'t write anything, just do the thing'
+    )
+}
+
+if (args['key-only']) {
+    console.log(key);
+    process.exit(0);
+}
+if (args['env'] || args['e']) {
+    dotenv = args['env'] ? args['env'] : args['e'];
+}
+if (args['set-key']) {
+    key = args['set-key'];
+}
+
+const file = fs.readFileSync(dotenv).toString('utf8');
+
+let lines = file.split('\n');
+
+for (let i = 0; i != lines.length; i++) {
+    let line = lines[i];
+    if (line.startsWith('APP_KEY=')) {
+        lines[i] = 'APP_KEY=' + key;
+    }
+}
+
+const newfile = lines.join('\n');
+
+if (!args['dry-run']) {
+    fs.writeFileSync(dotenv, newfile);
+}