Use boolean expressions/functions to conditionally attach a stream as a detour or an alternative destination stream.

This module is inspired by gulp-if. The difference is that this module is not created for gulp.

Following the above diagram, if bool is unsatisfied, then data from stream A will pass through to Stream D.

Otherwise, data will pipe to Stream B whenever bool is satisfied.

If branch is true, then data will not be piped back to Stream D. This is useful when emulating if/else with streams.

detour-stream is a function that creates a writable stream: https://nodejs.org/api/stream.html#stream_readable_pipe_destination_options

The writable stream is created via through2 v0.x.y: https://github.com/rvagg/through2

var detour = require('detour-stream');

stream = fs
  .createReadStream(filepath)
  .pipe(detour(someBoolean, decodeStream(someOptions))) // just pipe it
  .pipe(writeStream);

detour will pipe data to stream appropriately whenever bool is satisfied.

Type: boolean, or function

If a function is given, then the function is passed a data chunk. The function should return a boolean.

Stream for detour-stream to pipe data into whenever bool satisfies.

Type: boolean

Default: false

branch controls the flow behavior of whether detour-stream should pipe stream back to the main stream (i.e. detour stream).

If true, then gulp-if will not pipe stream back to the main stream. This emulates if/else stream flow.

MIT.