# ♻️ Rsync

> A pure TypeScript implementation of the [rsync algorithm](https://www.andrew.cmu.edu/course/15-749/READINGS/required/cas/tridgell96.pdf)

## Installation

```sh
npm install @dldc/rsync
```

## Usage

```ts
import { prepare, diff, apply } from '@dldc/rsync';

const checksum = prepare(destFile); // you can specify block size as second argument (default: 1024)
// send checksum to source
const patches = diff(sourceFile, checksum);
// send patches to dest
const syncedFile = apply(destFile, patches);
```

## Performance

This package was not designed to be fast. Since it's implemented fully in TypeScript, it's not as fast as the C implementation of rsync.
I tried to use the best practices to make it less slow but I did not benchmark it 🤷.

## Dependencies 🪶

This package has a single dependency [@dldc/erreur](https://github.com/dldc-packages/erreur) to define custom errors.


Sync directories and files with a remote server. 

@fullstacked/sync

Sync directories and files with a remote server

cplepage

sync

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Ambiguous License Classifier

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Bad text encoding

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Bad semver

Package has dependencies with an invalid semantic version. This could be a sign of beta, low quality, or unmaintained dependencies.

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Bad dependency semver

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What are bidirectional unicode control characters?

Bidirectional unicode control characters

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What is bin script confusion?

Bin script confusion

This Chrome extension includes content scripts that execute JavaScript on specified websites.

What are Chrome extension content scripts?

Chrome: Content Script

This Chrome extension requests host permissions to access specific websites or domains.

What are Chrome extension host permissions?

Chrome: Host Permission

This Chrome extension requests permissions to access browser APIs, user data, or system features.

What are Chrome extension permissions?

Chrome: Permission

This Chrome extension requests wildcard host permissions that grant broad access to websites.

What are Chrome extension wildcard host permissions?

Chrome: Wildcard Host Permission

Semantic versions published out of chronological order.

What is a chronological version anomaly?

Chronological version anomaly

Project maintainer's SSH key has been compromised.

What is a compromised SSH key?

Compromised SSH key

(Experimental) Copyleft license information was found.

What do I need to know about license files?

Copyleft License

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Title

Critical CVE

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High CVE

Uses debug, reflection and dynamic code execution features.

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Debug access

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Deprecated

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Deprecated SPDX exception

(Experimental) License is deprecated which may have legal implications regarding the package's use.

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Deprecated license

Package name is similar to other popular packages and may not be the package you want.

What is a typosquat?

Possible typosquat attack

Dynamic require can indicate the package is performing dangerous or unsafe dynamic code execution.

What is dynamic require?

Dynamic require

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What is an empty package?

Empty package

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What is environment variable access?

Environment variable access

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File dependency

Accesses the file system, and could potentially read sensitive data.

What is filesystem access?

Filesystem access

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Wildcard dependency

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An input argument to this GitHub Action is being exported as an environment variable. If a user of this action passes untrusted input, it could be used in an insecure manner by subsequent workflow steps.

What are GitHub Actions taint flows?

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An input argument to this GitHub Action is being passed back as an output. If a user of this action passes untrusted input, it could be used in an insecure manner by consuming workflows.

GitHub Actions: Input argument passed back as output

An input argument to this GitHub Action flows into a dangerous sink (such as shell command execution). This could allow a malicious user to inject commands or exploit the action.

GitHub Actions: Input argument flows to dangerous sink

A GitHub context variable (such as issue title, PR description, or comment body) is being exported as an environment variable. These context values are user-controlled and could be exploited by subsequent workflow steps.

GitHub Actions: GitHub context variable exported as environment variable

A GitHub context variable (such as issue title, PR description, or comment body) is being passed back as an output. These context values are user-controlled and could be exploited by consuming workflows.

GitHub Actions: GitHub context variable passed back as output

A GitHub context variable (such as issue title, PR description, or comment body) flows into a dangerous sink (such as shell command execution). This is a critical security issue that could allow command injection or code execution attacks.

GitHub Actions: GitHub context variable flows to dangerous sink

An environment variable flows into a dangerous sink (such as shell command execution). If this environment variable comes from an untrusted source, it could be exploited to inject commands.

GitHub Actions: Environment variable flows to dangerous sink

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What are git dependencies?

Git dependency

Contains a dependency which resolves to a GitHub URL. Dependencies fetched from GitHub specifiers are not immutable can be used to inject untrusted code or reduce the likelihood of a reproducible install.

What are GitHub dependencies?

GitHub dependency

AI has identified unusual behaviors that may pose a security risk.

What is an AI-detected potential code anomaly?

AI-detected potential code anomaly

AI has identified this package as a potential typosquat of a more popular package. This suggests that the package may be intentionally mimicking another package's name, description, or other metadata.

What is AI-detected potential typosquatting?

AI-detected possible typosquat

AI has identified this package as malware. This is a strong signal that the package may be malicious.

What is AI-detected potential malware?

AI-detected potential malware

AI has determined that this package may contain potential security issues or vulnerabilities.

What are AI-detected potential security risks?

AI-detected potential security risk

Contains native code (e.g., compiled binaries or shared libraries). Including native code can obscure malicious behavior.

Why is native code a concern?

Native code

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What are high entropy strings?

High entropy strings

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What are unicode homoglyphs?

Unicode homoglyphs

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What are http dependencies?

HTTP dependency

Install scripts are run when the package is installed or built. Malicious packages often use scripts that run automatically to execute payloads or fetch additional code.

What is an install script?

Install scripts

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What is an invalid manifest file?

Invalid manifest file

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What are invisible characters?

Invisible chars

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License change

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License exception

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License Policy Violation

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What's wrong with long strings?

Long strings

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Major refactor

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Known malware

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Manifest confusion

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Medium CVE

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Minified code

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Misc. License Issues

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Non-existent author

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What is a missing dependency?

Missing dependency

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What is a missing license?

Missing license

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Missing package tarball

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What is a mixed license?

Mixed license

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What is a modified license exception?

Modified license exception

(Experimental) Package contains a modified version of an SPDX license. Please read carefully before using this code.

@fullstacked/sync

♻️ Rsync

Installation

Usage

Performance

Dependencies 🪶

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