wbfs

Implementation of a basic subset of node's fs v0.12 api for the web with some caveats.

Run the integration tests in your browser.

Usage

var co = require('co');
var fs = require('wbfs');

co(function*() {
  yield fs.mkdir('/poems');

  var haiku = `An old silent pond...
               A frog jumps into the pond,
               Splash! Silence again.`

  // Write the haiku to a file.
  yield fs.writeFile('/poems/basho_matsuo.txt', haiku);

  // Oops! The author forgot to sign it.
  yield fs.appendFile('/poems/basho_matsuo.txt', ' -Basho');

  // Rename the poem file.
  yield fs.rename('/poems/basho_matsuo.txt', '/poems/frog_haiku.txt');

  // Spring cleaning! Rename the poems directory to 'haikus'.
  yield fs.rename('/poems', '/haikus');

  // Read the contents of the haikus directory.
  var list = yield fs.readdir('/haikus');
  console.log(list);  // ['frog_haiku.txt']

  // Read the frog poem file.
  var data = yield fs.readFile('/haikus/frog_haiku.txt');
  console.log(data);  // ${haiku} -Basho

  // Delete the frog poem.
  yield fs.unlink('/haikus/frog_haiku.txt');
  list = yield fs.readdir('/haikus');
  console.log(list);  // []

  // Delete the haikus directory.
  yield fs.rmdir('/haikus');
  try {
    yield fs.readdir('/haikus');
  } catch (error) {
    console.log(error.message);  // /haikus: No such file or directory
  }

  var watcher = fs.watch('/poems', { recursive: true });

  watcher.on('change', details => {
    console.log(details);  // { filename: '/poems/pi.txt' }
  });

  watcher.on('rename', details => {
    console.log(details);  // { oldName: '/poems/pi.txt', newName: /poems/irrational.txt' }
  });

  yield fs.writeFile('/poems/pi.txt', '3.1415');
  yield fs.rename('/poems/pi.txt', '/poems/irrational.txt');

  watcher.close();
});

// Or without co + generators...

fs.mkdir('poems')
.then(() => {
  // Write the haiku to a file.
  return fs.writeFile('/poems/basho_matsuo.txt', haiku);
})
.then(() => {
  // Oops! The author forgot to sign it.
  return fs.appendFile('/poems/basho_matsuo.txt', ' -Basho');
})
.then(() => {
  // Rename the poem file.
  return fs.rename('/poems/basho_matsuo.txt', '/poems/frog_haiku.txt');
})
.then(() => {
  // Spring cleaning! Rename the poems directory to 'haikus'.
  return fs.rename('/poems', '/haikus');
})
.then(() => {
  // Read the frog poem file.
  return fs.readdir('/haikus');
})
.then(list => {
  console.log(list);  // ['frog_haiku.txt']

  // Delete the frog poem.
  return fs.unlink('/haikus/frog_haiku.txt');
})
.then(() => {
  return fs.readdir('/haikus');
})
.then(list => {
  console.log(list);  // []

  // Delete the haikus directory.
  return fs.rmdir('/haikus');
})
.then(() => {
  fs.readdir('/haikus').catch(error => {
    console.log(error.message);  // /haikus: No such file or directory
  });
});

Caveats

This is only known to work in Firefox currently since support for indexedDB as well as es6 features such as promises, generators, proxies, arrow functions, destructuring, and template strings is assumed.

Invocation style

• No synchronous methods are implemented.
• Asynchronous methods use promises instead of callbacks.

File permissions

• Neither file permissions nor the methods that let you interact with them such as chown(), chmod(), and access() are implemented.
• Methods that take an optional mode argument in the nodejs api do not honor the mode (since there are no file permissions).

Low-level apis, buffers, and streams

• None of the lower-level methods like truncate(), ftruncate(), and fsync() are implemented.
• There are no buffers. The write(), readFile(), writeFile(), and appendFile() methods all coerce values to strings.
• createReadStream(), ReadStream, createWriteStream(), and WriteStream are not implemented.

fs.exists()

• exists() is not implemented since it is slated for deprecation in the nodejs api as of v0.12.