New peer architecture

Peer and Broker derive from BasePeer class. BasePeer is derived from ZmqAsyncioTaskManager. ZmqAsyncioTaskManager is derived from AsyncioTaskManager.

AsyncioTaskManager manages a set of tasks running inside asyncio message loop. Message loop can be owned by AsyncioTaskManager or borrowed. When message loop is owned new message loop is started in a new thread.

ZmqAsyncioTaskManager adds ZMQ asyncio context lifetime management to AsyncioTaskManager. ZMQ context can be borrowed or owned.

BasePeer extends ZmqAsyncioTaskManager by adding three ZMQ sockets:

• SUB used to receive broadcast messages, connects to Broker’s XPUB
• PUB used to send broadcast messages, connects to Broker’s XSUB
• REP used to answer synchronous messages (messages requiring an answer)

In ZMQ 3+ messages are filtered on PUB socket, so no redundant messages will be sent to clients.

Broker extends BasePeer by adding:

• XPUB/XSUB message proxy
• centralized peer registration authority
• query authority
• heartbeat monitor

Peer extends BasePeer by adding:

• initialization code/Broker connection code
• heartbeat message sending