fingerprinter

This Repo is no longer maintained

This repository is no longer active or maintained.

Please check out the replacement repositories

• Python (https://github.com/balain/fingerprinter-py) and
• Rust (https://github.com/balain/fingerprinter-rs)

Description

Take a (recursive) snapshot of a folder & compare against earlier snapshots.

Minimal external dependencies - only md5-file (to fingerprint individual files) & crypto (to set the snapshot filename, based on the full directory pathname)

The simple intent is to identify what files need to be uploaded to a remote webserver after a local static site rebuild (e.g. using Hugo). git could provide the same functionality, but brings a lot of baggage. This tool is very lightweight and simple to use with minimal dependencies.

External Dependencies

• TypeScript installed (tsc)
• Node modules
  • md5-file: Capture MD5 for individual files https://github.com/kodie/md5-file
  • crypto: For SHA256 hash of pathname (i.e. the snapshot filename)

Installation and Setup

1. Pull git pull https://github.com/balain/fingerprinter
2. Install Node modules npm install
3. Compile npm run build (or tsc or tsc --watch)

Functions

1. takeSnapshot(pathname): Takes a snapshot of the path provided. Nothing is returned.
2. isChanged(pathname, updateSnapshot=false): Compare the current contents with the previous snapshot, optionally updating the snapshot file to the current contents (default: do not update the snapshot file). (Promise)

• Returns an array - empty if no changes, otherwise, a list of filenames that have changed.
• Throws an error if the snapshot doesn't exist.

Running

From the commandline

• node fingerprinter.js add <pathname> to take a snapshot
• node fingerprinter.js check <pathname> to calculate the delta

In a Node script (via require...)

const fingerprinter = require('./fingerprinter.js')

// Take an explicit snapshot
// fingerprinter.takeSnapshot('.')

// Has anything has changed since the previous snapshot?
// ...do not update the snapshot file
fingerprinter.isChanged('.', false)
  .then((changes: any[]) => {
    console.log(`latestChanges: `, changes.length ? changes : 'no changes')
  })

// Has anything has changed since the previous snapshot?
// ...update the snapshot file
fingerprinter.isChanged('.', true)
  .then((changes: any[]) => {
    console.log(`latestChanges: `, changes.length ? changes : 'no changes')
  })

Snapshot File Info

Filename

sha256(absolutePathname) saved in the OS temp directory (per os.tmpdir())

File Format

[
  {
  "path": "...",
  "processDate": "...",
  "files": [
    { "name": "A",
      "md5": "..." }, 
    ...
  ]
]

License

Distributed under the MIT license. See LICENSE for more information.

https://github.com/balain/fingerprinter