Florian Scholz (Open Web Docs) Reporter
	Description • 7 years ago

It looks like bug 765993 introduced the X-SourceMap header.

WebKit also supports just "SourceMap", https://bugs.webkit.org/show_bug.cgi?id=114888

Unsure what Chrome does, but maybe we want to support the unprefixed version, too.

	Tom Tromey :tromey Assignee
	Comment 1 • 7 years ago

I think we do want to support it.
X-SourceMap is deprecated:
https://docs.google.com/document/d/1U1RGAehQwRypUTovF1KRlpiOFze0b-_2gc6fAH0KY0k/

	(no longer active)
	Comment 3 • 7 years ago
mozreview-review

Comment on attachment 8867810 [details]
Bug 1346936 - support SourceMap header in addition to X-SourceMap;

https://reviewboard.mozilla.org/r/139326/#review142712

Code-wise, looks great!

Can you please send an intent to ship for this to dev-platform as per https://wiki.mozilla.org/WebAPI/ExposureGuidelines?  Thanks!

::: dom/script/ScriptLoader.cpp:2736
(Diff revision 1)
>  
>      nsAutoCString sourceMapURL;
> +    rv = httpChannel->GetResponseHeader(NS_LITERAL_CSTRING("SourceMap"), sourceMapURL);
> +    if (NS_FAILED(rv)) {
> -    rv = httpChannel->GetResponseHeader(NS_LITERAL_CSTRING("X-SourceMap"), sourceMapURL);
> +      rv = httpChannel->GetResponseHeader(NS_LITERAL_CSTRING("X-SourceMap"), sourceMapURL);
> +    }

Do other UAs have this exact behavior (using SourceMap header and ignoring X-SourceMap if that exists, and otherwise falling back to X-SourceMap)?  I'm r+ing based on this assumption.

I'd appreciate if you can please clarify the specifcs in the intent to ship thread.

	Tom Tromey :tromey Assignee
	Comment 4 • 7 years ago

> Do other UAs have this exact behavior (using SourceMap header and ignoring X-SourceMap if that exists, and otherwise falling back to X-SourceMap)?  I'm r+ing based on this assumption.

I found this in chromium:

https://chromium.googlesource.com/chromium/src/third_party/+/master/WebKit/Source/bindings/core/v8/ScriptSourceCode.cpp#57

Still cloning webkit to dig in there, but given the path name, I would assume it does the same.

	(no longer active)
	Comment 5 • 7 years ago

(In reply to Tom Tromey :tromey from comment #4)
> > Do other UAs have this exact behavior (using SourceMap header and ignoring X-SourceMap if that exists, and otherwise falling back to X-SourceMap)?  I'm r+ing based on this assumption.
> 
> I found this in chromium:
> 
> https://chromium.googlesource.com/chromium/src/third_party/+/master/WebKit/
> Source/bindings/core/v8/ScriptSourceCode.cpp#57

Thanks for checking!

> Still cloning webkit to dig in there, but given the path name, I would
> assume it does the same.

If you mean the /WebKit/ in the path name, that doesn't mean much of anything any more after Blink forked WebKit.  Not much more than "ns" in our class names meaning NetScape.  :-)

	Tom Tromey :tromey Assignee
	Comment 6 • 7 years ago

> If you mean the /WebKit/ in the path name, that doesn't mean much of anything any more after Blink forked WebKit

Thanks.  I didn't know how much overlap there might still be.

Webkit does the same, see:

https://github.com/WebKit/webkit/blob/master/Source/WebCore/inspector/PageDebuggerAgent.cpp#L82-L88

I'll send the intent email soon.

	(no longer active)
	Comment 7 • 7 years ago

Awesome, thanks for checking!

	Pulsebot
	Comment 8 • 7 years ago

Pushed by ttromey@mozilla.com:
https://hg.mozilla.org/integration/autoland/rev/5ea7440b56ab
support SourceMap header in addition to X-SourceMap; r=Ehsan

	Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)
	Comment 9 • 7 years ago
bugherder

https://hg.mozilla.org/mozilla-central/rev/5ea7440b56ab

	Florian Scholz (Open Web Docs) Reporter
	Comment 10 • 7 years ago

Developer release notes
https://developer.mozilla.org/en-US/Firefox/Releases/55#Developer_Tools

Reference page
https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/SourceMap

Compat data
https://github.com/mdn/browser-compat-data/pull/229