Baseline Widely available
Note: This feature is available in Web Workers.
The pipeThrough()
method of the ReadableStream
interface provides a chainable way of piping the current stream through a transform stream or any other writable/readable pair.
Piping a stream will generally lock it for the duration of the pipe, preventing other readers from locking it.
SyntaxpipeThrough(transformStream)
pipeThrough(transformStream, options)
Parameters
transformStream
A TransformStream
(or an object with the structure {writable, readable}
) consisting of a readable stream and a writable stream working together to transform some data from one form to another. Data written to the writable
stream can be read in some transformed state by the readable
stream. For example, a TextDecoder
, has bytes written to it and strings read from it, while a video decoder has encoded bytes written to it and uncompressed video frames read from it.
options
Optional
The options that should be used when piping to the writable
stream. Available options are:
preventClose
If this is set to true
, closing the source ReadableStream
will no longer cause the destination WritableStream
to be closed.
preventAbort
If this is set to true
, errors in the source ReadableStream
will no longer abort the destination WritableStream
.
preventCancel
If this is set to true
, errors in the destination WritableStream
will no longer cancel the source ReadableStream
.
signal
If set to an AbortSignal
object, ongoing pipe operations can then be aborted via the corresponding AbortController
.
The readable
side of the transformStream
.
TypeError
Thrown if the writable
and/or readable
property of transformStream
are undefined.
In the following example (see Unpack chunks of a PNG for the full code running live, and png-transform-stream for the source code), an image is fetched and its body retrieved as a ReadableStream
.
Next, we log the contents of the readable stream, use pipeThrough()
to send it to a new function that creates a gray-scaled version of the stream, then log the new stream's contents too.
// Fetch the original image
fetch("png-logo.png")
// Retrieve its body as ReadableStream
.then((response) => response.body)
.then((rs) => logReadableStream("Fetch Response Stream", rs))
// Create a gray-scaled PNG stream out of the original
.then((body) => body.pipeThrough(new PNGTransformStream()))
.then((rs) => logReadableStream("PNG Chunk Stream", rs));
Specifications Browser compatibility See also
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