head-stream
v0.0.4
Published
Passthrough stream for acting upon the first buffer emitted in a stream. Like the head command of e.g. head and tail, first and rest.
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head-stream
Passthrough stream for acting upon the first buffer emitted in a stream. Like the head command of e.g. head and tail, first and rest.
usage
Pipe a stream to it, as well as a callback, and that callback will be called with the first buffer like so:
someStream.pipe(headStream(onFirstRow)).pipe(someOtherStream)
function onFirstRow(buffer, done) {
// do stuff with buffer
done() // tells head-stream to start emitting data downstream
}
Until you call done()
, someOtherStream
won't receive any data.
You can also pass in options:
var options = {includeHead: true}
someStream.pipe(headStream(onFirstRow, opts)).pipe(someOtherStream)
includeHead
means that someOtherStream
will receive all the buffers that were written to head-stream. By default the first header is not included.