rar.js - JavaScript Unrar Utility

rar.js provides a pure javascript implementation of the rar format, allowing you to extract or manipulate packed data client-side and server-side.

Multiple inputs are supported: AJAX, File API (HTML5) and local disk (NodeJS).

Example

Using rar.js is fairly straight forward.

Rar.fromLocal('myfile.rar').then((archive) => {
  // Use archive here
  console.log(archive.entries);
});

Rar.fromUri('/test.rar').then((archive) => {
  // Use archive here
});

Rar.fromFile(input.files[0]).then((archive) => {
  // Use archive here
});

Unsupported features (TODO)

• Large file support (currently the entire file will be in memory when RarArchive.get is called)
• Decompression support
• Encryption support
• Recognise volumes/split archives
• Parse other entries (e.g. comments)

Saving files

By using RarArchive#get(file), you can retrieve a Blob of a specified file within the archive.

const file = archive.get(archive.entries[0]);
const url = URL.createObjectURL(file);
// Do something with url here
// like creating an <a> tag with the download attribute set

Split Volumes

When dealing with entries you have retrieved via RarArchive.get(), make sure you check the RarEntry.partial boolean.

If this boolean is true, sending/saving the Blob will result in a partial file. You must request that the user open the previous or next volume and prepend/append to the Blob to be able to retrieve the full file.

To find out if the file is continued in a previous or next volume, see RarEntry.continues and RarEntry.continuesFrom.

RarArchive

• Rar.fromFile(file) where file is a HTML5 File instance
• Rar.fromLocal(path) where path is a string of a local filesystem path
• Rar.fromUri(uri) where uri is a string of a URI

All three of these entrypoints return a Promise which resolves to a RarArchive.

• RarArchive#entries An array of RarEntry instances contained within this archive
• RarArchive#get(RarEntry) Retrieves the specified RarEntry resolves a promise with a Blob

RarEntry Properties

• name File name
• path File path within the archive, including file name
• size Size of the unpacked file
• sizePacked Size of the packed file
• crc CRC of the file
• offset Offset within the archive
• blockSize Size of this entry within the archive (including headers)
• headerSize Size of the header for this entry
• encrypted Boolean specifying if the file is password protected or not
• version RAR version used
• time Date/time string for the file
• method Compression method used, will equal one of the method constants
• os Operating system used (Windows, MS-DOS, OS/2, Unix, Mac or BeOS)
• partial Boolean specifying if the file is partial available due to split volumes. Use RarEntry.continues and RarEntry.continuesFrom.
• continuesFrom Boolean specifying if the file continues from a previous volume
• continues Boolean specifying if the file continues into the next volume

The following constants also exist for use with RarEntry.method:

• Rar.RarMethod.STORE
• Rar.RarMethod.FASTEST
• Rar.RarMethod.FAST
• Rar.RarMethod.NORMAL
• Rar.RarMethod.GOOD
• Rar.RarMethod.BEST

License

MIT