2015-08-22 Peer app notes
After getting starting with ClojureScript, I am thinking about whether and how to make applications, that are the same on server, and client side, where the app itself is a distributed network.
Basic concepts:
- Homogeneous API, – same stack for “client” and “server”. Essentially daemon processes as well as user applications should be the same kind of peers. Not just the same language, as with html5+node.js, but truly peer-oriented, where even the libraries are the same.
- Offline, – peers might disconnect from the network, and return back online later on.
- Distributed, – instead of thinking about an application running on a computer, we should try to think about the computer as a large network of peers.
- REST-configurable
So what I need in addition to standard HTML5
- Message queues
- Communication between peers
- Logging
- Offline-support
- Database, with offline support and syncing
- Offline support
- Also host resources
- User authentication
- Caching and REST-support
- Daemons
- WebRTC-connection server
- Search/discovery
The message queue, database, auth and daemons are the important once, the rest can be added later.
Database can be solved PouchDB, (CouchDB or CouchBase+Sync+proxy for replication/serverside)
Auth is done through a combination between the database and the mesage queue.
Daemons are just daemonised headless browsers, – possibly with access to extra APIs, – but they connect as any other peer, and you can communicate with them through. Daemons can also be used for email, non-cors http, etc.
The message queue is interesting. These are some thoughts about it:
- Channels are one-way, and have a unique send and receive endpoint, ie. it is random, and if you do not know the endpoint you cannot send or receive.
- A message consist of the following:
- Timestamp, when arrived in the common db
- Session-id for the sender/client
- Message content
- API
- Create a new channel, – returns two endpoints (send/receive)
- Get authenticated user-id for a given session id
- Subscribe to messages on a channel since a given point in time, – or only new ones
- Send message to a channel
- Underlying database
- map from send-id to receive-id (not exposed)
- session-id to user-id
- messages (channel recieve-id, timestamp, message-content)