245283 - Add a * topic for the observerservice

Status: RESOLVED FIXED

(Core :: XPCOM, enhancement)

Description

[timeless]

There are many topics out there, but there's no easy way to fish for them.

dougt and I have decided that "*" would be a good topic to mean "I want them all".

Comment 1

[Benjamin Smedberg]

I *so* hate this. Can't we use NSPR logging level 5 to discover observer topics?
If not, make this DEBUG-only?

Comment 2

[timeless]

Attachment: support global observers, and sample consumer

Comment 3

[Doug Turner (:dougt)]

I kinda like it. :-)

Comment 4

[Darin Fisher]

Benjamin: why exactly do you "*so* hate this"?  it seems harmless enough to
me... what are your concerns?

Comment 5

[Benjamin Smedberg]

I really don't like this because I'm afraid people might actually use it. 

Receiving all observer notifications will be a performance drag, and I haven't
seen a use-case other than "discovery" of observer topics, which should be
handled through documentation and can be worked-around through PRlogging.

Comment 6

[Doug Turner (:dougt)]

Comment on attachment 149785 [details] [diff] [review]
support global observers, and sample consumer

Put the nsObserverLogger.js example in mozilla/xpcom/sample/.  Also, add a
license to the file.

Be prepared to disable if tb numbers go up.  Also, the logic in the if
statement needs a comment above it.

Comment 7

[Darin Fisher]

> Put the nsObserverLogger.js example in mozilla/xpcom/sample/.  Also, add a
> license to the file.

Hmm... that doesn't seem like the best place for this file.  xpcom/sample is an
isolated code sample that demonstrates how to write a basic component (in C++ or
JS) and create a basic executable that uses xpcom.  I think nsObserverLogger.js
would just be noise in that directory for anyone trying to use xpcom/sample as a
learning tool.  Perhaps we should have subdirectories, or perhaps this should
simply live elsewhere.  Either way, it seems wrong to lump them together.

Comment 8

[Darin Fisher]

btw, i also have a webprogresslistener.js file that i've been meaning to add to
the source tree.  i just haven't figured out a good place for it.  it seems like
we could have a collection of helpful components like these that live in some
gecko tools directory or something like that.

Comment 9

[Doug Turner (:dougt)]

i think it is a okay sample of how to use js components and the nsIObserver
service.  

Comment 10

[Darin Fisher]

oh, absolutely... it's good to have samples.  but, should they all live in this
one directory?  it seems like xpcom/sample is nice because it demonstrates the
basics of interface and implementation without clutter.  there's great value in
that for newbies imo.

Comment 11

[Doug Turner (:dougt)]

timeless, just land the code and forget about landing the sample.  maybe the
wiki is a better place.

Comment 12

[Christian :Biesinger (don't email me, ping me on IRC)]

xpcom/tests/, maybe?

Comment 13

[timeless]

mozilla/xpcom/ds/nsObserverService.cpp 	3.31