332774 - Create API allowing extensions to hook into the session-restore service

Status: RESOLVED FIXED

(Firefox :: Tabbed Browser, enhancement)

Description

[Dietrich Ayala (:dietrich)]

From http://wiki.mozilla.org/Firefox2/Requirements:

"API allowing extensions to contribute items to be saved/restored across sessions"

Comment 1

[Bradley Chapman (not reading bugmail, still gone but not forever)]

What sort of API is planned here? I'm visualizing something like this:

var gSession = Components.classes["@mozilla.org/browser/sessionstore;1"]
                             .getService(nsCI.nsISessionStore);
var newAttr = gSession.newAttribute('example-number-list');
newAttr.spec = "0,1,2,3,4,5,6,7,8,9";
gSession.addAttribute(newAttr);

// or
var newAttr2 = Components.classes["@mozilla.org/browser/sessionstore;1"]
                             .createInstance(nsCI.nsISessionAttribute);
for (i = 0; i < 10; ++i) {
   newAttr2.append(i);
}

// later
gSession.removeAttribute(newAttr);

where newAttr is a new instance of an nsISessionAttribute, with a spec member similar to nsIURI as well as other accessor functions that can take a string or a number and parse it into the format used by the backing code.

Comment 2

[John Mellor (Jomel)]

It seems to me this API will be used to store attributes/objects both per tab and per session.

Per tab requirements might be done by allowing extensions to register the names of attributes (and perhaps js objects) to be stored if present on tab nodes.

As for per session data, a similar approach might be possible where the API is given an object reference (or several) which it backs up whenever it saves a session, though for maximum flexibility some kind of SessionSave 'event' letting you execute a little code whenever a session is saved, would be very powerful.

Either way some kind of SessionRestore 'event' would be useful to help extensions resume a session.

Comment 3

[Eric Shepherd [:sheppy]]

Anything happening with this?  Trying to figure out if there'll be an API to document in the Fx2 timeframe.

Comment 4

[Dietrich Ayala (:dietrich)]

I've updated the wiki with some information about this:

http://wiki.mozilla.org/SessionRestoreAPI

I'd like to get this in for Fx2, but as freeze is next week, whether I can get to it really depends on how the next couple of days go.

Comment 5

[Dietrich Ayala (:dietrich)]

swag 2 days to get basic session storage per the requirement.

Comment 6

[Dietrich Ayala (:dietrich)]

Attachment: exposes the window/tab data APIs, w/ some tests

This exposes the ability to store strings by key for windows and tabs.

(I'll move the tests into a separate tests directory whenever this gets checked in.)

Comment 7

[Mike Connor [:mconnor]]

Comment on attachment 227190 [details] [diff] [review]
exposes the window/tab data APIs, w/ some tests

mmm, tests.  Is this a framework davel is pushing, or something you just cooked up?

Comment 8

[Dave Liebreich [:davel]]

Hey Dietrich,

I took a quick look at the tests - is there a reason other than running with chrome privs that you need this to be a xul doc? 

Comment 9

[Dietrich Ayala (:dietrich)]

(In reply to comment #7)
> (From update of attachment 227190 [details] [diff] [review] [edit])
> mmm, tests.  Is this a framework davel is pushing, or something you just cooked
> up?
> 

i wrote this, but it should be easy enough to convert to davel's format, once it's finalized.

(In reply to comment #8)
> Hey Dietrich,
> 
> I took a quick look at the tests - is there a reason other than running with
> chrome privs that you need this to be a xul doc? 
> 

i need chrome privs, and to be able to open windows, tabs, and inspect menus, etc, basically a full browser environment.

Comment 10

[Mike Beltzner [:beltzner, not reading bugmail]]

Can we get this landed on trunk ASAP and smoketested? Then nominate for approval1.8.1?

Comment 11

[Dietrich Ayala (:dietrich)]

i had to manually merge, due to conflicts w/ recent changes. should be on trunk pretty soon, once i test the updated patch.

Comment 12

[Dietrich Ayala (:dietrich)]

Comment on attachment 227190 [details] [diff] [review]
exposes the window/tab data APIs, w/ some tests

Low risk, no UI, no l10n impact.

Comment 13

[Eric Shepherd [:sheppy]]

Looks like this is making the beta?  Where do I look to dig up all the juicy details on the API so I can write a doc about it?

Comment 14

[Dietrich Ayala (:dietrich)]

(In reply to comment #13)
> Looks like this is making the beta?  Where do I look to dig up all the juicy
> details on the API so I can write a doc about it?
> 

Howdy, I'll try to add API details on the wiki today:

http://wiki.mozilla.org/SessionRestoreAPI

Also, there's example usage in the tests here:

http://lxr.mozilla.org/mozilla/source/browser/components/sessionstore/test/nsSessionStoreTest.xul

Comment 15

[Simon Bünzli]

(In reply to comment #6)
> Created an attachment (id=227190)

>+      Components.returnCode = -1; //zeniko: or should we rather fail silently?

Instead of copy/pasting (and mis-quoting me ;-)), it would've been better to do the same thing you already did for undoCloseTab:

+       Components.returnCode = Cr.NS_ERROR_INVALID_ARG;

Apart of that, one relevant part of the API is still missing: allowing extensions to retrieve/restore complete session states.

Dietrich: Are there any bugs pending on these issues already?

Comment 16

[John Mellor (Jomel)]

RE: dev-doc-needed

As an extension developer currently using the session store api, I find the documentation on developer.mozilla.org sufficient, if not perfect.

http://developer.mozilla.org/en/docs/Session_store_API
http://developer.mozilla.org/en/docs/nsISessionStore

Though it would be quite be nice to have official documentation on the format of the json object returned, rather than having to work it out manually.

Comment 17

[Eric Shepherd [:sheppy]]

Do we want to document the JSON object?  If so, I'll have to poke around and figure out where it's built so I can do so.

Comment 18

[Eric Shepherd [:sheppy]]

Since there seems not to be any interest in documenting the JSON format, I'm marking this as dev-doc-complete.  Please re-tag it if this is in error.