bugfix: ZENKO-623 Make MD5 optional for backbeat

lib/routes/routeBackbeat.js

@@ -237,12 +237,6 @@ function putData(request, response, bucketInfo, objMd, log, callback) {
         log.error(errMessage);
         return callback(errors.BadRequest.customizeDescription(errMessage));
     }
-    const contentMD5 = request.headers['content-md5'];
-    if (contentMD5 === undefined) {
-        errMessage = 'bad request: missing content-md5 header';
-        log.error(errMessage);
-        return callback(errors.BadRequest.customizeDescription(errMessage));
-    }
     const context = {
         bucketName: request.bucketName,
         owner: canonicalID,
@@ -270,7 +264,9 @@ function putData(request, response, bucketInfo, objMd, log, callback) {
                 });
                 return callback(err);
             }
-            if (contentMD5 !== md5) {
+            // Optional param if replicating from source cloud server.
+            const contentMD5 = request.headers['content-md5'];
+            if (contentMD5 && contentMD5 !== md5) {
                 return callback(errors.BadDigest);
             }
             const { key, dataStoreName } = retrievalInfo;