Sounds fantastic, especially when it comes from you Joseph. Just a side note regarding SVN-Git issue - it is possible to combine both by using git-svn - it works fine for me.
On Wed, Jun 19, 2013 at 9:22 PM, Joseph Gentle <jose...@gmail.com> wrote: > I've given half a dozen talks about ShareJS over the last 3 years, and > almost every time I give a talk, someone asks me whether you can use > ShareJS in a peer-to-peer way instead of just through a single server. > > "You say it works like subversion. Can it work like Git?" > "Can you have a document shared between multiple servers?" > > Sigh no. ShareJS & Wave's algorithms were invented in 1995. Back then, > it was news when someone put up a new website. > > "What about Wave Federation?" Appropriately, it works like IRC, but > using XML. Its complicated, its vulnerable to netsplits and its buggy. > I guess its like IRC except it doesn't actually work. > > So lets fix that! Lets modernize wave and make it federate properly. > On the way we have a great opportunity to make it simpler and cleaner. > > > To start, I want to build a generic P2P OT container. This is a simple > wrapper that contains a set of OT documents and defines a network > protocol for keeping them in sync. The container needs to be able to > talk to another instance of itself running somewhere else and > syncronize documents between the two instances. > > Thats all I want this container to do - it should be as lightweight as > possible, so we can port it to lots of different languages and > environments. I want that code running in websites, in giant server > farms, in vim, and everywhere in between. It won't have any database > code, network code, users or a user interface (though it'll need APIs > to support all of that stuff). At its core it just does OT + protocol > work to syncronize documents. > > What are the documents? Well, like ShareJS, I'd like to support > multiple different kinds of data. We'll need to be able to support > wave's conversation model, but I'd also like to support arbitrary > JSON. Doing OT over arbitrary JSON structures would allow other > applications to be built on top of wave, using wave as a data platform > ("Glorious messaging bus in the sky"). It'd also be super useful for > gadgets and user data. > > There's three models I can imagine for what wavelets could look like: > > Option 1: All documents in the container have a unique name and a > type. This is how ShareJS works. We could have a JSON type and a > wavelet type. This is simple, but not particularly extensible (it > makes it hard to embed JSON inside a conversation, and vice versa). > > Option 2: At the root of every document is a JSON object. Leaves in > the JSON structure can be subdocuments, which could be rich text for > blips, or any other type we think of down the road. > > Option 3: We make another layer, which can contain a set of documents. > So, a wavelet could contain a JSON document describing the > conversation structure, some rich text documents for blips and another > JSON document containing gadget data or something. Access control > rules are at the container level. This is (sort of) how wavelets work > today. > > The OT itself I imagine building along the lines of Torben Weis's P2P > OT theory that he made in Lightwave: > https://code.google.com/p/lightwave/ . Briefly, every operation gets a > hash (like git). We add tombstones to wave's OT type and remove > invertability, so the transform function supports TP2. We also add a > prune function (inverse transform) which allows the history list to be > reordered (so you don't have to transform out on every site). The hard > part is figuring out which operations to sync, and which operations > need to be reordered. I'd like to go over the details with Michael > MacFadden and anyone else who's interested - there may well be a > better system that we should use instead. If there is, I'd like to > know about it now. > > > Once thats built, we can start integrating it into WIAB. The simplest > way to do the client-server protocol and federation will be to simply > reuse the container's protocol (obviously wrapped for access control). > We could also strip it down for pure client-server interaction if we > want, to make it less chatty. (If we decide thats worthwhile.) > > I'm also thinking about full end-to-end encryption. Especially in the > wake of the PRISM stuff, I'd quite like to make something secure. > Snowden: "Encryption works. Properly implemented strong crypto systems > are one of the few things that you can rely on. Unfortunately, > endpoint security is so terrifically weak that NSA can frequently find > ways around it." -- > > http://www.guardian.co.uk/world/2013/jun/17/edward-snowden-nsa-files-whistleblower > . > > > All of this should happen in the experiments branch (with a mirror on > github). > > The design decisions that we make here will be really hard to change > later, so I'd like to get this right. I'd like as much feedback as > possible. But please restrain yourself from complaining that its too > much work. You're not the boss of me :D > > Also, I expect the core OT piece to be no longer than a few thousand > lines. We can definitely pull that off - its just figuring out what > those lines are thats the tricky part. > > Cheers > Joseph >