1204830 - Check meta/global engines in Sync app

Status: RESOLVED FIXED

(Firefox OS Graveyard :: Sync, defect, P3)

Description

[Michiel de Jong [:michielbdejong]]

"The client needs to validate the meta/global record on every request." https://docs.services.mozilla.com/sync/lifeofasync.html

But:
[info/collections] is a utility API provided by the storage service that reveals which collections exist on the server and when they were last modified.

That means we can save work, as follows:
* Retrieve info/collections.
* If none of the data collections we need have have changed according to info/collections, stop here.
* Retrieve meta/global and check storage format.
* Only retrieve crypto/keys if it has changed according to info/collections.
* Only retrieve data collections that have changed according to info/collections.

Comment 1

[Michiel de Jong [:michielbdejong]]

Looks like info/collections was moved to meta/global.engines

Comment 2

[GitHub Autolander Bot]

Attachment: [gaia] michielbdejong:1204830-check-metaglobal-engines > mozilla-b2g:master

Comment 3

[Michiel de Jong [:michielbdejong]]

Comment on attachment 8686123 [details] [review]
[gaia] michielbdejong:1204830-check-metaglobal-engines > mozilla-b2g:master

See http://docs.services.mozilla.com/sync/storageformat5.html#metaglobal-record

Comment 4

[Michiel de Jong [:michielbdejong]]

(In reply to Michiel de Jong [:michielbdejong] from comment #1)
> Looks like info/collections was moved to meta/global.engines

Created https://github.com/mozilla-services/docs/issues/55 about the docs issue.

Comment 5

[Michiel de Jong [:michielbdejong]]

Turns out Syncto doesn't support retrieving info/collections. I'm not so sure anymore now whether we really need this.

Comment 6

[Michiel de Jong [:michielbdejong]]

If we check meta/globals for the engines like in this patch, then I think it's not so important to also check info/collections (would only be a performance optimization when syncing many collections, and for now we're only syncing one or two).

Comment 7

[Michiel de Jong [:michielbdejong]]

What do you think, shall we just merge this to check the engines from m/g, and then leave it at that?

Comment 8

[Fernando Jiménez Moreno [:ferjm]]

Sounds good to me.

Comment 9

[Fernando Jiménez Moreno [:ferjm]]

https://github.com/mozilla-b2g/gaia/commit/1e9a2a701dec486dd94bdb925019bb6ead8291ca