Add let (#50)

* Add let

* Add note about browser use in readme

README.md

@@ -1,12 +1,7 @@
 # Fleek Storage Js
 Fleek Storage Js is an SDK to interact with Fleek Storage.
 
-# Installation
-The package can be installed through npm.
-
-`npm install @fleekhq/fleek-storage-js`
-
-It can also be installed through yarn.
+:exclamation: Please do not use this package directly in the browser. Your API secret will be visible to users of that page.  If you need to make requests from the client side, please use an S3 SDK directly with pre-signed urls: https://docs.aws.amazon.com/AmazonS3/latest/userguide/using-presigned-url.html.
 
 `yarn add @fleekhq/fleek-storage-js`
 
@@ -186,4 +181,4 @@ const myFile = await fleekStorage.getFileFromHash({
 |param  	|type  	|description  	|
 |-:	|-	|-	|
 | hash 	| String 	|  The hash of the requested file	|
-| getFileFromHashOptions 	| Array, optional, defaults to [] 	| An array specifying additional options when it comes to fetching by hash. Possible values for the array includes `buffer` (this returns the whole file at once instead of chunks) |
+| getFileFromHashOptions 	| Array, optional, defaults to [] 	| An array specifying additional options when it comes to fetching by hash. Possible values for the array includes `buffer` (this returns the whole file at once instead of chunks) |

methods/listFiles.js

@@ -47,6 +47,8 @@ const listFiles = async ({
     const files = await getFileList(s3, bucketName, prefix);
 
     const promises = files.map(async (key, index) => {
+      let hash;
+
       if (getOptions.includes(GET_OPTIONS.HASH)) {
         hash = await getHashFromKey(bucketName, key);
       }