slice-source

A readable stream reader that reads a desired number of bytes.


Keywords
binary, stream, reader
License
BSD-3-Clause
Install
npm install slice-source@0.4.0

Documentation

slice-source

A readable stream reader that allows you to pull the specified number of bytes from the underlying readable stream. For example:

<!DOCTYPE html>
<script src="https://unpkg.com/slice-source@0"></script>
<script>

fetch("https://cors-anywhere.herokuapp.com/")
  .then(response => {
    return (function read(reader) {
      return reader.slice(40).then(value => {
        if (value == null) return;
        console.log(value);
        return read(reader);
      });
    })(sources.slice(response.body));
  })
  .catch(error => console.error(error.stack));

</script>

API Reference

# slice(stream) <>
# slice(reader)
# slice(source)

If the specified source exposes a source.slice method, it is assumed to be a sliceable source and returned as-is. Otherwise, if the specified reader exposes a reader.read method, it is assumed to be a readable stream reader, and a new sliceable source for the specified reader is returned. Otherwise, the specified reader is assumed to be a readable stream, and a new sliceable source for the reader returned by stream.getReader is returned.

# source.slice(length) <>

Returns a Promise for the next chunk of data from the underlying stream, yielding a Uint8Array of length bytes, or the remaining bytes of the underlying stream if the underlying stream has more than zero but fewer than length bytes remaining, or null when no bytes remain in the stream.

# source.read() <>

Returns a Promise for the next chunk of data from the underlying stream. The yielded result is an object with the following properties:

  • value - a Uint8Array, or undefined if the stream ended
  • done - a boolean which is true if the stream ended

# source.cancel() <>

Returns a Promise which is resolved when the underlying stream has been destroyed.