Messaging v1.x - Geodan/cow GitHub Wiki

COW makes use of websocket messages to communicate with peers. A peer is not necessarely a COW instance but can be any client that adheres to websocket standards and the COW messaging protocol. See the image in docs for an overview of the message flow.

webscocket confirms connection by returning a CID

{
    "action": "connected",
    "payload": {"cid":3}
}

Client should:

1. assign CID to self.
2. Let the world know about self with 'newPeer'
3. Let the world know about own herd with 'herdInfo'
4. Sent feature idlist to world with 'newPeerFidList'

the server noticed a peer disconnecting and send its connection-id to the pool

{
    "action":"peerGone",
    "payload":{"peerCid":2,"newCid":2}
}

Client should:

1. remove peer with peerCid from list.
2. Assign newCid to self and sent new Cid to world with 'updatePeers'.

You joined and receive the status from peers like connection-id, uid, extent

{
    "uid":<origin-id>,
    "target":<target-id>,
    "action":"informPeer",
    "payload":{
        "options":{"uid":<src-uid>,"cid":<src-cid>,"family":"alpha"},
        "view":{"left":<left long>,"bottom":<bottom lat>,"right":<right long>,"top":<top lat>},
        "owner":{"name":<name of peer owner>},
        "position":{"coords":{"longitude":<lon>,"latitude":<lat>},"time":<timestamp>},
        "video":{"state":<on/off>}
    }
}

Client should: add peerinformation to peerslist

The alpha peer sends a sync message with new features and a feature request

{
    "uid":<origin-id>,
    "target":<target-id>,
    "action":"syncPeer",
    "payload":{
        "requestlist":[<feature ids>],
        "pushlist":[<features>],
        "storename":<herdid>
     }
}

Client should:

1. sent features from requestlist to other peers with 'requestedFeats'
2. add features for own use from pushlist

requested feats are returning from peer

{
    "uid":<origin-id>,
    "action":"requestedFeats",
    "payload":{
        "features":[<features>],
        "storename":<herdid>
    }
}

Client should: add features to own store

a peer is gone and everybody has a new connection-id, recieve a connectionID with UID

{
    "uid":<origin-id>,
    "action":"updatePeers",
    "payload":{
        "uid":<origin-id>,
        "connectionID":<origin-cid>
    }
}

Client should: update peerlist with new CID's

a new peer just joined, recieve its status: connection-id, uid, extent

{
    "uid":<origin-id>,
    "action":"newPeer",
    "payload":{
        "uid":<origin-id>,
        "cid":<origin-cid>,
        "family":"alpha"
     }
}

Client should:

1. Add peer to own peerslist
2. Sent own peerinformation with 'informPeer'
3. Sent info on own herd with 'herdInfo'

a new peer just sent it's fidlist

{
    "uid":<origin-id>,
    "action":"newPeerFidList",
    "payload":{
        "fids":[<fidlist>],
        "storename":<herdid>
    }
}

Client should: (only when being the alphapeer)

1. Find id's that are new(er) compared to own list and add to requestlist
2. Find id's that are old(er) compared to own list and add to pushlist
3. Sent requestlist and pushlist with 'syncPeer'

A peer has changed, update the peer

{
    "uid":<origin-id>,
    "action":"peerUpdated",
    "payload":{
      "video":{"state":<on/off>}}} 
or    "owner":{"name":<peers owner>}}} 
or    "extent":{"bottom":0,"left":0,"top":1,"right":1}}}
or    "point":{"coords":{"longitude":<lon>,"latitude":<lat>},"time":<timestamp>}
}}

Client should: update the peer in the peerslist accordingly

a new object was drawn or updated by a peer

{
    "uid":<origin-id>,
    "action":"newFeature",
    "payload":"{\"options\":<jsonfeature>}"
}

Client should: add feature to own store TODO: THERE's SOMETHING WRONG WITH THE JSON HERE, too complex

A peer request information about a herd herdInfo

Info about a herd comes in...

{
    "uid":<origin-id>,
    "action":"herdInfo",
    "payload":{
        "uid":<herdid>,
        "name":<herdname>,
        "peeruid":<????>,
        "active":<true/false>
    }
}

Not sure what the purpose of peeruid is here

Client should: ......