1397145 - Remove moz-blob support from XHR

Status: RESOLVED FIXED

(Core :: DOM: Core & HTML, enhancement)

Description

[Andrea Marchesini [:baku]]

In bug 1335365 I introduced Telemetry::MOZ_BLOB_IN_XHR to count how often moz-blob type is used in XHR. The result is: 0.16% I would like to proceed with removing this non-spec feature.

Comment 1

[Andrea Marchesini [:baku]]

Attachment: moz_blob.patch

Comment 2

[Olli Pettay [:smaug][[e-mail]]]

0.16% sounds quite high, a lot higher than what I'd expect.

Comment 3

[Olli Pettay [:smaug][[e-mail]]]

But where do you see that 0.16%.

Comment 4

[Olli Pettay [:smaug][[e-mail]]]

Comment on attachment 8904879 [details] [diff] [review]
moz_blob.patch

I'd prefer if this landed only once FF57 is in beta.
Unless there is some particular reason to remove it now.

(We should try to avoid causing any possible regressions in 57)

Comment 5

[Andrea Marchesini [:baku]]

(In reply to Olli Pettay [:smaug] from comment #3)
> But where do you see that 0.16%.

If I do it correctly, I compare the number of MOZ_BLOB_IN_XHR and the number of any other ID sent by constantly. I used: NUMBER_OF_PROFILES because that ID is used at startup.

Comment 6

[Andrea Marchesini [:baku]]

Green on try: https://treeherder.mozilla.org/#/jobs?repo=try&revision=83377f20f8b02d994f47a56bc2ceb7562857f266&selectedJob=128876770

Please, land this patch when 57 is the new beta.

Comment 7

[Andrea Marchesini [:baku]]

Attachment: moz_blob.patch

Comment 8

[Andrea Marchesini [:baku]]

NI RyanVM to land this patch after 57

Comment 9

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/cfb739b281f8
Remove the support for moz-blob type in XHR, r=smaug

Comment 10

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/cfb739b281f8

Comment 11

[Kohei Yoshino]

Posted the site compatibility note: https://www.fxsitecompat.com/en-CA/docs/2017/prefixed-xmlhttprequest-response-types-including-moz-blob-are-no-longer-supported/

Comment 12

[Chris Mills [:cmills]]

I have documented this, by adding a note to the responseType page and removing the information about those values:

https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest/responseType#Browser_compatibility

And by adding a note to the Fx58 rel notes:

https://developer.mozilla.org/en-US/Firefox/Releases/58#APIs_2

Let me know if that looks OK. Thanks!

Comment 13

[Andrea Marchesini [:baku]]

moz-chunked-arraybuffer has not been removed yet. It's used internally by PDFjs and probably something else.

Comment 14

[Chris Mills [:cmills]]

(In reply to Andrea Marchesini [:baku] from comment #13)
> moz-chunked-arraybuffer has not been removed yet. It's used internally by
> PDFjs and probably something else.

Ah, OK. I've added it back in to the values list, and updated the notes accordingly.