ReadableStream.prototype.text(), .blob(), and .bytes() #1311
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Adds utility methods to akin to the Body mixin for fully reading the contents of a ReadableStream as either text, a Blob, or a Uint8Array.
| otherwise. | ||
| 1. Assert: either |signal| is undefined, or |signal| [=implements=] {{AbortSignal}}. | ||
| 1. Let |decode as Uint8Array| be an algorithm that takes a [=byte sequence=] |bytes| and runs the steps: | ||
| 1. Let |arrayBuffer| be a new {{ArrayBuffer}} whose contents are |bytes|. |
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This is a faithful copy of the text in fetch, but fetch has a bug which is copied here. It doesn't necessarily need to be fixed here, just gotta make sure it gets fixed here as well when fixed upstream.
| 1. Let |successSteps| given a [=byte sequence=] |bytes| be to run |processBody| given |bytes|. | ||
| 1. Let |errorSteps| optionally given an exception |exception| be to run |processBodyError| given |exception|. | ||
| 1. Let |reader| be the result of getting a reader for |stream|. If that threw an exception, then run |errorSteps| with that exception and return. | ||
| 1. [=read all bytes|Read all bytes=] from |reader|, given |successSteps| and |errorSteps|. |
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I think Bikeshed can compensate for different capitalisation automatically.
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| It performs the following steps: | ||
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| 1. Assert: |stream| [=implements=] {{ReadableStream}}. |
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Maybe we could have a PrepareToConsume abstract op to encapsulate these common steps?
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| dictionary ConsumeBytesOptions { | ||
| AbortSignal signal; | ||
| USVString type = ""; |
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- This
typeis not super clear about what type it means, maybeblobType? Especially if we want to put more stream related options, because we already havetypeinUnderlyingSource. - Blob uses DOMString instead of USVString: https://w3c.github.io/FileAPI/#ref-for-dfn-BPtype
- Should we have a separate dictionary without
typefor other non-blob methods?
| @@ -2661,6 +2688,99 @@ create them does not matter. | |||
| 1. Return « |branch1|, |branch2| ». | |||
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| <div algorithm> | |||
| To <dfn lt="fully read">fully read</dfn> a {{ReadableStream}} |stream|, given an algorithm |processBody|, and an algorithm |processBodyError|, run these steps. |processBody| must be an algorithm accepting a [=byte sequence=]. |processBodyError| must be an algorithm optionally accepting an exception. | |||
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Do we need this lt? Same for other <dfn>s.
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| <div algorithm> | ||
| The <dfn lt="consume fully with abort">consume fully with abort</dfn> algorithm, given a {{ReadableStream}} |stream|, an optional {{AbortSignal}} |signal|, and an algorithm that takes a [=byte sequence=] and returns a JavaScript or throws an exception |convertBytesToJSValue|, runs these steps: |
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"consume fully" or "fully consume"? We already have "fully read", so maybe consistency?
And also "an algorithm |convertBytesToJSValue| that ..."
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| 1. Let |promise| be [=a new promise=]. | ||
| 1. Let |errorSteps| given |error| to be [=reject=] |promise| with |error|. | ||
| 1. Let |successSteps| given a [=byte sequence=] |data| be to [=resolve=] |promise| with the result of running |convertBytesToJSValue| with |data|. If that threw an exception, then run |errorSteps| with that exception. |
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Perhaps you want to name them as processBody and processBodyError as that's what the parameters of "fully read" are? Or maybe "fully read" parameters should be success/errorSteps instead.
| 1. If |stream|.[=ReadableStream/[[state]]=] is "`readable`", [=set/append=] the following action action to |actions|: | ||
| 1. return ! [$ReadableStreamCancel$](|stream|, |error|). | ||
| 1. Otherwise, return [=a promise resolved with=] undefined. | ||
| 1. [=Shutdown with an action=] consisting of [=getting a promise to wait for all=] of the actions |
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This is pipeTo specific, maybe we can simply call ReadableStreamCancel?
Adds utility methods to akin to the Body mixin for fully reading the contents of a ReadableStream as either text, a Blob, or a Uint8Array.
This is a first pass at addressing #1019 ....
In this, I add only the
text(),bytes(), andblob()methods.text()returns a promise for UTF-8 decoded text,bytes()returns a promise for aUint8Array, andblob()returns a promise for aBlob. It is modeled heavily on the fetch specBodymixin definitions with a few tweaks.Refs: #1019
(See WHATWG Working Mode: Changes for more details.)
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