to-vfile

What is to-vfile?

The 'to-vfile' npm package is a utility for working with virtual files in Node.js. It allows you to create, read, write, and manipulate file objects in memory, which can be particularly useful for processing files in a pipeline without needing to interact with the filesystem directly.

What are to-vfile's main functionalities?

Creating a virtual file

This feature allows you to create a virtual file object with specified path and contents. The file object can then be manipulated in memory.

const vfile = require('to-vfile');
const file = vfile({ path: 'example.txt', contents: 'Hello, world!' });
console.log(file);

Reading a file from the filesystem

This feature allows you to read a file from the filesystem into a virtual file object. The contents of the file are loaded into memory, and you can manipulate the file object as needed.

const vfile = require('to-vfile');
vfile.read('example.txt', 'utf8', (err, file) => {
  if (err) throw err;
  console.log(file);
});

Writing a virtual file to the filesystem

This feature allows you to write a virtual file object to the filesystem. The contents of the virtual file are saved to the specified path.

const vfile = require('to-vfile');
const file = vfile({ path: 'example.txt', contents: 'Hello, world!' });
vfile.write(file, err => {
  if (err) throw err;
  console.log('File written!');
});

Other packages similar to to-vfile

vinyl

Vinyl is a similar package that provides a virtual file format. It is commonly used in the Gulp ecosystem for handling file transformations in memory. Compared to 'to-vfile', Vinyl is more focused on stream-based workflows and integrates tightly with Gulp.

memfs

Memfs is a package that provides an in-memory filesystem. It allows you to perform filesystem operations in memory, which can be useful for testing and mocking. While 'to-vfile' focuses on individual file objects, Memfs provides a broader filesystem abstraction.

README

to-vfile

Create a vfile from a filepath. Optionally populates them from the file system as well. Can write virtual files to file system too.

Install

This package is ESM only: Node 12+ is needed to use it and it must be imported instead of required.

npm:

npm install to-vfile

Use

import {toVFile, readSync} from 'to-vfile'

console.log(toVFile('readme.md'))
console.log(toVFile(new URL('./readme.md', import.meta.url)))
console.log(readSync('.git/HEAD'))
console.log(readSync('.git/HEAD', 'utf8'))

Yields:

VFile {
  data: {},
  messages: [],
  history: ['readme.md'],
  cwd: '/Users/tilde/projects/oss/to-vfile'
}
VFile {
  data: {},
  messages: [],
  history: ['readme.md'],
  cwd: '/Users/tilde/projects/oss/to-vfile'
}
VFile {
  data: {},
  messages: [],
  history: ['.git/HEAD'],
  cwd: '/Users/tilde/projects/oss/to-vfile',
  value: <Buffer 72 65 66 3a 20 72 65 66 73 2f 68 65 61 64 73 2f 6d 61 73 74 65 72 0a>
}
VFile {
  data: {},
  messages: [],
  history: ['.git/HEAD'],
  cwd: '/Users/tilde/projects/oss/to-vfile',
  value: 'ref: refs/heads/main\n'
}

API

This package exports the following identifiers: toVFile, read, readSync, write, and writeSync. There is no default export.

toVFile(options)

Create a virtual file. Works like the vfile constructor, except when options is string or Buffer, in which case it’s treated as {path: options} instead of {value: options}, or when options is a WHATWG URL object, in which case it’s treated as {path: fileURLToPath(options)}.

read(options[, encoding][, callback])

Creates a virtual file from options (toVFile(options)), reads the file from the file system and populates file.value with the result. If encoding is specified, it’s passed to fs.readFile. If callback is given, invokes it with either an error or the populated virtual file. If callback is not given, returns a Promise that is rejected with an error or resolved with the populated virtual file.

readSync(options[, encoding])

Like read but synchronous. Either throws an error or returns a populated virtual file.

write(options[, fsOptions][, callback])

Creates a virtual file from options (toVFile(options)), writes the file to the file system. fsOptions are passed to fs.writeFile. If callback is given, invokes it with an error, if any. If callback is not given, returns a Promise that is rejected with an error or resolved with the written virtual file.

writeSync(options[, fsOptions])

Like write but synchronous. Either throws an error or returns a populated virtual file.

Contribute

See contributing.md in vfile/.github for ways to get started. See support.md for ways to get help.

This project has a code of conduct. By interacting with this repository, organization, or community you agree to abide by its terms.

License

MIT © Titus Wormer