1360409 - WebIDL bindgen doesn't support [SecureContext] on enums or dictionaries

Status: RESOLVED INVALID

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

Description

[Chris Pearce [:cpearce (Not reading bugmail)]]

The EME spec requires its MediaKeySessionType enum to have the [SecureContext] attribute:

https://w3c.github.io/encrypted-media/#idl-def-mediakeysessiontype

But if I add that, I get an (opaque) error:

 0:12.40 Elapsed: 0.35s; From ../../dist/idl: Kept 0 existing; Added/updated 1101; Removed 0 files and 0 directories.
 0:13.99 Traceback (most recent call last):
 0:13.99   File "c:\mozilla-build\python\Lib\runpy.py", line 162, in _run_module_as_main
 0:13.99     "__main__", fname, loader, pkg_name)
 0:13.99   File "c:\mozilla-build\python\Lib\runpy.py", line 72, in _run_code
 0:13.99     exec code in run_globals
 0:13.99   File "c:\Users\chris\src\central\python\mozbuild\mozbuild\action\webidl.py", line 19, in <module>
 0:13.99     sys.exit(main(sys.argv[1:]))
 0:13.99   File "c:\Users\chris\src\central\python\mozbuild\mozbuild\action\webidl.py", line 15, in main
 0:13.99     manager.generate_build_files()
 0:13.99   File "c:\Users\chris\src\central\dom\bindings\mozwebidlcodegen\__init__.py", line 248, in generate_build_files
 0:13.99     self._parse_webidl()
 0:13.99   File "c:\Users\chris\src\central\dom\bindings\mozwebidlcodegen\__init__.py", line 333, in _parse_webidl
 0:13.99     parser.parse(data, path)
 0:13.99   File "c:\Users\chris\src\central\dom\bindings\parser\WebIDL.py", line 6851, in parse
 0:13.99     self._productions.extend(self.parser.parse(lexer=self.lexer, tracking=True))
 0:13.99   File "c:\Users\chris\src\central\other-licenses\ply\ply\yacc.py", line 263, in parse
 0:13.99     return self.parseopt(input,lexer,debug,tracking,tokenfunc)
 0:13.99   File "c:\Users\chris\src\central\other-licenses\ply\ply\yacc.py", line 710, in parseopt
 0:13.99     p.callable(pslice)
 0:13.99   File "c:\Users\chris\src\central\dom\bindings\parser\WebIDL.py", line 5354, in p_Definitions
 0:13.99     p[2].addExtendedAttributes(p[1])
 0:13.99   File "c:\Users\chris\src\central\dom\bindings\parser\WebIDL.py", line 1969, in addExtendedAttributes
 0:13.99     assert len(attrs) == 0
 0:13.99 AssertionError
 0:13.99 Makefile:55: recipe for target 'codegen.pp' failed
 0:13.99 mozmake.EXE[5]: *** [codegen.pp] Error 1
 0:14.00 c:/Users/chris/src/central/config/recurse.mk:100: recipe for target 'dom/bindings/export' failed
 0:14.00 mozmake.EXE[4]: *** [dom/bindings/export] Error 2
 0:14.00 mozmake.EXE[4]: *** Waiting for unfinished jobs....
 0:33.51 c:/Users/chris/src/central/config/recurse.mk:32: recipe for target 'export' failed
 0:33.51 mozmake.EXE[3]: *** [export] Error 2
 0:33.51 c:/Users/chris/src/central/config/rules.mk:519: recipe for target 'default' failed
 0:33.51 mozmake.EXE[2]: *** [default] Error 2
 0:33.51 c:/Users/chris/src/central/client.mk:419: recipe for target 'realbuild' failed
 0:33.51 mozmake.EXE[1]: *** [realbuild] Error 2
 0:33.52 client.mk:170: recipe for target 'build' failed
 0:33.52 mozmake.EXE: *** [build] Error 2
 0:33.55 273 compiler warnings present.
2

EME also requires [SecureContext] on dictionaries, and that's not working either.

[SecureContext] is working as expected for interface definitions.

Comment 1

[Boris Zbarsky [:bzbarsky]]

> The EME spec requires its MediaKeySessionType enum to have the [SecureContext] attribute:

What does that even mean?  enum names are not web-exposed, so what does [SecureContext] mean here?

> But if I add that, I get an (opaque) error:

Yeah, maybe a better error there would be "extended attributes are not allowed here" or something...  Filed bug 1360557.

> EME also requires [SecureContext] on dictionaries, and that's not working either.

What would _that_ mean?  Again, dictionaries are not web-exposed.

In any case, from <https://heycam.github.io/webidl/#SecureContext>:

  If the [SecureContext] extended attribute appears on an interface, partial interface,
  namespace, partial namespace, interface member, or namespace member, it indicates
  that the construct is exposed only within a secure context.

Note that neither enums nor dictionaries are in the list of things [SecureContext] is allowed to appear on, with good reason: it doesn't mean anything there.

Please file issues on the EME spec to not have bogus cargo-culted IDL, and maybe even make use of the IDL checkers that are available to make sure their IDL is valid...

Comment 2

[Boris Zbarsky [:bzbarsky]]

Or put another way, enums and dictionaries are not "exposed" in any meaningful way, so it's nonsense to restrict their (already nonexistend) exposure to only secure contexts.