connections state needs improvement

[karth295]

The connections state is nice to have, but it's a little confusing to use.

1. It looks different on the client and server. On the client, fetch('/connections') -> {key: '/connections', all: [{...}, {...}]}, and on the server, fetch('connections') -> {key: 'connections', connId1: {...}, connId2: {...}}

2. It doesn't work with the state interface -- must call fetch/save

[toomim]

For 1, the different isn't client vs. server, but rather the client vs. master bus on the server. For instance:

master = require('statebus').serve({
  client: (client) => {
    ...
    client.fetch('connections')   // Here you get {key: 'connections', all: [...]}
}

The client vs. master bus distinction has always bugged me, and I'm sorry that it's biting you here too. I'd like a better solution to giving each client their own state space, without confusion like this. I've also considered making a sub-space within a single bus, like perhaps /client/23423/* would substitute for the client bus.

For 2, maybe this is the same problem as 1? I just tested the state interface on the client and it works. The global state object is probably pointing at the master bus, but maybe that shouldn't exist, like you pointed out in #40.

[karth295]

Yeah that's very confusing.

Also I don't necessarily want to start a server if I just want to write unit tests. I'll open a PR to tawk to show you what I'm working on.

[karth295]

Also I think state.connections / state['/connections'] should return either an array of connections or an object with connid -> connections, rather than this weird {key: ..., all: [...]}

[karth295]

That would make unit tests in my PR a lot shorter / more readable.

[toomim]

I agree about the all field in connections being annoying.

The reason connections looks like {key: ..., all: [...]} is because the current version of statebus requires every piece of state to be a javascript object with a key on it. Once we get the state proxy working better, we can transition all state to the JSON encoding and make it a regular array or object.

However, I have improvements in mind for both the JSON encoding and the network protocol, which will break compatibility, and I want to implement them all at once in version 7. The new JSON encoding will simplify the implementation of the state Proxy, which makes me want to wait for it before I fix the bugs in the current implementation of the Proxy. Unfortunately, I've been entirely obsessed with the synchronization algorithm lately, and haven't put any work into the new encoding, protocol, or the Proxy.

[toomim]

I've listed the upcoming breaking changes here: https://wiki.invisible.college/statebus/dev

You'll see that refactoring /connections is on the list!