♻️ use trampoline function to keep backward compatibility

Issue: CLDSRV-823

Author: DarkIsDude

lib/api/bucketGet.js

@@ -261,7 +261,13 @@ function handleResult(listParams, requestMaxKeys, encoding, authInfo, bucketName
  * @param  {function} log - Werelogs request logger
  * @return {Promise<object>} - object containing xml and additionalResHeaders
  */
-async function bucketGet(authInfo, request, log) {
+async function bucketGet(authInfo, request, log, callback) {
+    if (callback) {
+        return bucketGet(authInfo, request, log)
+            .then(result => callback(null, ...result))
+            .catch(err => callback(err, null, err.additionalResHeaders));
+    }
+
     const params = request.query;
     const bucketName = request.bucketName;
     const v2 = params['list-type'];
@@ -377,12 +383,5 @@ async function bucketGet(authInfo, request, log) {
 module.exports = {
     processVersions,
     processMasterVersions,
-    bucketGet: (...args) => {
-        const callback = args.at(-1);
-        const argsWithoutCallback = args.slice(0, -1);
-
-        bucketGet(...argsWithoutCallback)
-            .then(result => callback(null, ...result))
-            .catch(err => callback(err, null, err.additionalResHeaders));
-    },
+    bucketGet,
 };

lib/api/objectGetLegalHold.js

@@ -24,7 +24,13 @@ const standardMetadataValidateBucketAndObjPromised = (metadataValParams, actionI
  * @param {object} log - Werelogs logger
  * @return {Promise<object>} - object containing xml and additionalResHeaders
  */
-async function objectGetLegalHold(authInfo, request, log) {
+async function objectGetLegalHold(authInfo, request, log, callback) {
+    if (callback) {
+        return objectGetLegalHold(authInfo, request, log)
+            .then(result => callback(null, ...result))
+            .catch(err => callback(err, null, err.additionalResHeaders));
+    }
+
     log.debug('processing request', { method: 'objectGetLegalHold' });
 
     const { bucketName, objectKey, query } = request;