add prefix

fonctions/getServerPrefix.js

@@ -0,0 +1,33 @@
+const sqlite3 = require('sqlite3').verbose();
+require('dotenv').config();
+
+function getServerPrefix(serverID) {
+  return new Promise((resolve, reject) => {
+    let db = new sqlite3.Database('db.db', sqlite3.OPEN_READWRITE, (err) => {
+      if (err) {
+        console.error(err.message);
+        reject(err);
+      }
+    });
+
+    db.get('SELECT prefix FROM prefix WHERE serverID = ?', [serverID], (err, row) => {
+      if (err) {
+        console.error(err.message);
+        reject(err);
+      }
+      if (row) {
+        resolve(row.prefix);
+      } else {
+        resolve(process.env.DEFAULT_PREFIX);
+      }
+    });
+
+    db.close((err) => {
+      if (err) {
+        console.error(err.message);
+      }
+    });
+  });
+}
+
+module.exports = getServerPrefix;