Asar is a simple extensive archive format, it works like tar that concatenates all files together without compression while having random access support. You can pass in a transform option, which is a function, that either returns nothing or a stream. Transform. The latter will be used on files that will be in the .asar file to transform them. There is also an unofficial grunt plugin to generate asar archives at bwin/grunt-asar. Asar uses Pickle to safely serialize binary value to file, there is also a node.js binding of Pickle class. The header_size and header are serialized with Pickle class, and header_size's Pickle object is 8 bytes. offset and size record the information to read the file from the archive, the offset starts from 0 so you have to manually add the size of header_size and header to the offset to get the real offset of the file.
Features
- Support random access
- Use JSON to store files' information
- Very easy to write a parser
- Requires Node 10 or later
- Exclude multiple resources from being packed
- Use programatically