Added a new function and change some es6 features to es5

source/factory.js

@@ -211,6 +211,19 @@ function createClient(remoteURL, username, password) {
             return putFile.putFileContents(remoteFilename, data, putOptions);
         },
 
+        /**
+         * Get the upload link
+         * Only supported for Basic authentication or unauthenticated connections.
+         * @param {String} remoteFilename The path of the remote file location
+         * @param {PutOptions=} options The options for the request
+         * @memberof ClientInterface
+         * @returns {String} A upload URL
+         */
+        getFileUploadLink: function getFileUploadLink(remoteFilename, options) {
+            var putOptions = merge(baseOptions, options || {});
+            return putFile.getFileUploadLink(remoteFilename, putOptions);
+        },
+
         /**
          * Stat a remote object
          * @param {String} remotePath The path of the item

source/interface/putFile.js

@@ -30,6 +30,22 @@ function putFileContents(filePath, data, options) {
     return fetch(fetchURL, fetchOptions).then(responseHandlers.handleResponseCode);
 }
 
+function getFileUploadLink(filePath, options) {
+    let fetchURL = joinURL(options.remoteURL, encodePath(filePath));
+    fetchURL += "?Content-Type=application/octet-stream";
+    const protocol = /^https:/i.test(fetchURL) ? "https" : "http";
+    if (options.headers.Authorization) {
+        if (/^Basic /i.test(options.headers.Authorization) === false) {
+            throw new Error("Failed retrieving download link: Invalid authorisation method");
+        }
+        const authPart = options.headers.Authorization.replace(/^Basic /i, "").trim();
+        const authContents = Buffer.from(authPart, "base64").toString("utf8");
+        fetchURL = fetchURL.replace(/^https?:\/\//, `${protocol}://${authContents}@`);
+    }
+    return fetchURL;
+}
+
 module.exports = {
-    putFileContents: putFileContents
+    getFileUploadLink,
+    putFileContents
 };