Download offset file unzipper

Central directory information from a zipfile on S3. Range-headers are used to avoid reading the whole file. Unzipper does not ship with with the aws-sdk so you have to provide an instantiated client as first arguments. The params object requires Bucket and Key to fetch the correct file.Example:const unzipper = require('./unzip');const AWS = require('aws-sdk');const s3Client = AWS.S3(config);async function main() { const directory = await unzipper.Open.s3(s3Client,{Bucket: 'unzipper', Key: 'archive.zip'}); return new Promise( (resolve, reject) => { directory.files[0] .stream() .pipe(fs.createWriteStream('firstFile')) .on('error',reject) .on('finish',resolve) });}main();Open.buffer(buffer, [options])If you already have the zip file in-memory as a buffer, you can open the contents directly.Example:// never use readFileSync - only used here to simplify the exampleconst buffer = fs.readFileSync('path/to/arhive.zip');async function main() { const directory = await unzipper.Open.buffer(buffer); console.log('directory',directory); // ...}main();Open.custom(source, [options])This function can be used to provide a custom source implementation. The source parameter expects a stream and a size function to be implemented. The size function should return a Promise that resolves the total size of the file. The stream function should return a Readable stream according to the supplied offset and length parameters.Example:// Custom source implementation for reading a zip file from Google Cloud Storageconst { Storage } = require('@google-cloud/storage');async function main() { const storage = new Storage(); const bucket = storage.bucket('my-bucket'); const zipFile = bucket.file('my-zip-file.zip'); const customSource = { stream: function(offset, length) { return zipFile.createReadStream({ start: offset, end: length && offset + length }) }, size: async function() { const objMetadata = (await zipFile.getMetadata())[0]; return objMetadata.size; } }; const directory = await unzipper.Open.custom(customSource); console.log('directory', directory); // ...}main();Open.[method].extract()The directory object returned from Open.[method] provides an extract method which extracts all the files to a specified path, with an optional concurrency (default: 1).Example (with concurrency of 5):unzip.Open.file('path/to/archive.zip') .then(d => d.extract({path: '/extraction/path', concurrency: 5}));Please note: Methods that use the Central Directory instead of parsing entire file can be found under OpenChrome extension files (.crx) are zipfiles with an extra header at the start of the file. Unzipper will parse .crx file with the streaming methods (Parse and ParseOne).Streaming an entire zip file (legacy)This library began as an active fork and drop-in replacement of the node-unzip to address the following issues:finish/close events are not always triggered, particular when the input stream is slower than the receiversAny files are buffered into memory before passing on to entryOriginally the only way to use the library was to stream the entire zip file. This method is inefficient if you are only interested in selected files from the zip files. Additionally this method can be error prone since it relies on the local file headers which could be wrong.The structure of this fork is similar to the original, but uses Promises and inherit guarantees provided by node streams to ensure low memory footprint and emits finish/close events at the end of processing. The new Parser will push any parsed entries downstream if you pipe from it, while still supporting the legacy entry event as well.Breaking changes: The new Parser will not automatically drain entries if there are no listeners or pipes in

April 3, 2023 | Unzipper Blog Editor Streamline Your File Compression and Decompression: Unzipper’s Superiority Over 7zip ExplainedWhile 7zip is a widely known and popular file compression tool, Unzipper offers a more comprehensive solution, making it a superior choice for many users. Here are some reasons why Unzipper stands out as a better alternative to 7zip:User-friendly interface: Unzipper features an intuitive and easy-to-navigate interface, making it simple for users of all experience levels to compress and decompress files effortlessly. This is particularly beneficial for those who may not be as tech-savvy or familiar with file compression tools.Versatile file support: Unzipper not only supports popular formats like 7z, zip, and rar but also handles other formats such as gzip, tar.gz, and more. This makes Unzipper a one-stop solution for all your file compression and decompression needs.Advanced compression algorithms: Unzipper utilizes state-of-the-art algorithms to compress files effectively, ensuring optimal file size reduction without sacrificing data integrity or quality.Integrated file management: Unzipper goes beyond simple compression and decompression. It also includes file management features, allowing users to create zip files, extract rar files, convert rar to zip, and even handle zip bomb situations safely.Comprehensive multimedia compression: While 7zip primarily focuses on document and archive formats, Unzipper is designed to compress a wide range of file types, including PDF, JPEG, PNG, and MP4. This versatility makes it an ideal choice for users who work with various multimedia formats.Unzipper is an exceptional file compression and decompression tool that offers several advantages over 7zip. With its user-friendly interface, support for a wide range of file formats, advanced compression algorithms, and integrated file management features, Unzipper is the ultimate solution for all your file compression.Click Here to Download Unzipper

May 8, 2023 | Unzipper Blog Editor When it comes to file compression, finding the right settings can make a significant difference in terms of file size and quality. In this comprehensive guide, we’ll explore the best zip file compression settings for different types of files, empowering you to save storage space without compromising the integrity of your files. With the help of Unzipper, a reliable and user-friendly compression tool, you can easily optimize your file compression process.Text FilesFor documents, spreadsheets, and code files, it is recommended to use moderate compression settings to balance file size reduction and text readability. Opt for a compression level that preserves the content while effectively reducing the file size. Unzipper offers customizable settings to achieve the desired balance.Image FilesWhen compressing image files, the ideal settings depend on the format. For JPEG files, select a compression level that maintains a good balance between image quality and file size. Higher compression levels result in smaller file sizes but may slightly compromise image quality. However, for PNG files, choose lossless compression to retain image details and transparency.Audio and Video FilesCompressing audio and video files requires careful consideration. It’s recommended to use specialized compression tools for these file types, such as dedicated audio and video codecs. Unzipper supports popular audio and video formats, allowing you to optimize compression settings specific to these file types while preserving audio and visual quality.Archiving Multiple FilesWhen compressing multiple files into an archive, it’s essential to strike a balance between compression level and extraction time. Opt for a compression method that suits your specific needs. For instance, if you require faster extraction times, choose a compression level that offers good compression ratios without sacrificing extraction speed.Remember, the best zip file compression settings may vary depending on the specific requirements of your files and your intended use. Experiment with different compression levels and methods to find the optimal balance between file size reduction and quality preservation.With Unzipper, you have a versatile tool at your disposal. Its intuitive interface and customizable compression settings allow you to fine-tune the compression process according to your needs. Whether you’re dealing with text files, images, audio, video, or multiple file archives, Unzipper provides a user-friendly experience and helps you achieve efficient compression results.Optimize your file storage, save space, and enhance file transfer efficiency with Unzipper’s best zip file compression settings tailored to different file types. Start maximizing your file compression potential today!Click Here to Download Unzipper