GrumpTech-FS-Hasher

A JavaScript node module for for producing message digests of files and directories. The message digest of a directory is computed as the hash of the message digests of all of the contents of the directory.

Change Log

The change history can be viewed here

Security Policy

Please refer to our security policy for information on which versions are receiving security updates and how to report security vulnerabilities.

Installation

npm install grumptech-fs-hasher

Basic Usage

Loading the module in NodeJS

const fsHasher = require(‘grumptech-fs-hasher’);

Testing the module in NodeJS       Example usage is shown in the file: ./test/testscript.js

npm run test-rel

The module exports two objects:

  1. HASH_ALGORITHMS: An enumeration of supported hashing algorithm.
  2. FSHasher: Object to perform the hashing and reporting.

FSHasher API

The FSHasher object provides the interface below

Version:
Read-only property for the version of the hasher module.       @return {string}

IsBusy:
Read-only property indicating that the object is busy performing an operation.       @return {boolean}

Algorithm:
Read-only property of the current hashing algorithm. Default: ‘sha256’       @return {string}

Source:
Read-only property for the source(s) to perform the hashing.       @return {string | string[]}:

Build:
Constructs a hierarchy of files and directories to be hashed.       @parm {string | string[]} [source]       @return {Promise(boolean)} - A promise that when resolved will indicate if the file system heirarchy was built or not. true if built. false otherwise.

Compute:
Generate a message digest of the source (and all child items).       @param {string} - A string representing the hashing algorithm to use. HASH_ALGORITHMS is an enum of common algorithms.       @return {Promise(string)} - A promise that when resolved will provide a string representing the overall hash of the root source. If the hierarchy has not been built or the root source is busy, the promise will resolve to and empty string

Report:
Build a report of the file system hierarchy with the results of the hashing.       @return {Promise(string)} - A promise that when resolved will provide a string containing a CSV delimited report. If the hierarchy has not been built or the root source is busy, the promise will resolve to an empty string.       CSV Format:       Field #1: Type - ‘(D)’-Directory, ‘(F)’-File, ‘(B)’-Batch       Field #2: Source - Path of the File System object. Will be prepended with spaces corresponding to the depth of the result item.       Field #3: Digest - Message digest of the item. If it has not been computed, it will default to undefined.

FindDuplicates:
Finds duplicate file system objects.       @return {Promise(Map{key:digest, value:source[]))} - A promise that when resolved will provide a map/dictionary. The key of the dictionary will be “common” message digest and the value will be an array of strings containing the sources sharing the digest. Unique items will not be specified in the result.

License

Refer to LICENSE.md for information regarding licensincg of this source code.