Repository navigation
#duplex is missing from RequestInit #1483
Description
The Fetch WG introduced a new duplex property to RequestInit1 back in July that undici is now abiding by when making payload requests with a ReadableStream2. They have added this new duplex property into their own RequestInit types, but as this is now a part of the core fetch specification it should be included here.
https://fetch.spec.whatwg.org/#request-class
Footnotes
Reacted by nasso, akletus, Jeremy Rose, Jay Linski, Nate Tippie, Pavel Shurygin, William Villeneuve, Oskar Löfgren, Scott Talbot, Christian de Botton and 19 more
Activity
Add required duplex option to RequestInit see nodejs/node#46221 and m…
haukepribnow commentedon Jul 30, 2023
Would this really be as easy to close as only removing this line?
add duplex property in RequestInit fixes microsoft#1483
Bashamega commentedon Apr 1, 2025
That is correct Hauke Pribnow (@haukepribnow)
Bashamega commentedon Apr 1, 2025
The reason #1729 wasn't merged and we removed this type is that it is only supported by Blink, and in order for a type to be added, it needs to be supported by at least two major browser engines.
orshrim-trail commentedon Jul 27, 2026
Seems like it's supported by Chrome and Edge (not sure if they count as two different browsers...)
Bashamega commentedon Jul 28, 2026
Chrome and Edge use the same browser engine Blink, so they count as the same browser.
To be a different browser, it needs to run on another engine: WebKit or Gecko
HolgerJeromin commentedon Jul 28, 2026
https://developer.mozilla.org/en-US/docs/Web/API/Request/duplex#browser_compatibility
says blink only right now