added test connector, webrtc connector, ideas to apply operations with very low overhead
This commit is contained in:
Kevin Jahns
223
src/Connector.js
Normal file
223
src/Connector.js
Normal file
@@ -0,0 +1,223 @@
|
||||
|
||||
class AbstractConnector {
|
||||
/*
|
||||
opts
|
||||
.role : String Role of this client ("master" or "slave")
|
||||
.userId : String that uniquely defines the user.
|
||||
*/
|
||||
constructor (opts) {
|
||||
if (opts == null){
|
||||
opts = {};
|
||||
}
|
||||
if (opts.role == null || opts.role === "master") {
|
||||
this.role = "master";
|
||||
} else if (opts.role === "slave") {
|
||||
this.role = "slave";
|
||||
} else {
|
||||
throw new Error("Role must be either 'master' or 'slave'!");
|
||||
}
|
||||
this.role = opts.role;
|
||||
this.connections = {};
|
||||
this.userEventListeners = [];
|
||||
this.whenSyncedListeners = [];
|
||||
this.currentSyncTarget = null;
|
||||
}
|
||||
setUserId (userId) {
|
||||
this.os.setUserId(userId);
|
||||
}
|
||||
onUserEvent (f) {
|
||||
this.userEventListeners.push(f);
|
||||
}
|
||||
userLeft (user : string) {
|
||||
delete this.connections[user];
|
||||
if (user === this.currentSyncTarget){
|
||||
this.currentSyncTarget = null;
|
||||
this.findNextSyncTarget();
|
||||
}
|
||||
for (var f of this.userEventListeners){
|
||||
f({
|
||||
action: "userLeft",
|
||||
user: user
|
||||
});
|
||||
}
|
||||
}
|
||||
userJoined (user, role) {
|
||||
if(role == null){
|
||||
throw new Error("You must specify the role of the joined user!");
|
||||
}
|
||||
if (this.connections[user] != null) {
|
||||
throw new Error("This user already joined!");
|
||||
}
|
||||
this.connections[user] = {
|
||||
isSynced: false,
|
||||
role: role
|
||||
};
|
||||
for (var f of this.userEventListeners) {
|
||||
f({
|
||||
action: "userJoined",
|
||||
user: user,
|
||||
role: role
|
||||
});
|
||||
}
|
||||
}
|
||||
// Execute a function _when_ we are connected.
|
||||
// If not connected, wait until connected
|
||||
whenSynced (f) {
|
||||
if (this.isSynced === true) {
|
||||
f();
|
||||
} else {
|
||||
this.whenSyncedListeners.push(f);
|
||||
}
|
||||
}
|
||||
// returns false, if there is no sync target
|
||||
// true otherwise
|
||||
findNextSyncTarget () {
|
||||
if (this.currentSyncTarget != null && this.connections[this.currentSyncTarget].isSynced === false) {
|
||||
throw new Error("The current sync has not finished!")
|
||||
}
|
||||
|
||||
for (var uid in this.connections) {
|
||||
var u = this.connections[uid];
|
||||
if (!u.isSynced) {
|
||||
this.currentSyncTarget = uid;
|
||||
this.send(uid, {
|
||||
type: "sync step 1",
|
||||
stateVector: hb.getStateVector()
|
||||
});
|
||||
return true;
|
||||
}
|
||||
}
|
||||
// set the state to synced!
|
||||
if (!this.isSynced) {
|
||||
this.isSynced = true;
|
||||
for (var f of this.whenSyncedListeners) {
|
||||
f()
|
||||
}
|
||||
this.whenSyncedListeners = null;
|
||||
} return false;
|
||||
}
|
||||
// You received a raw message, and you know that it is intended for to Yjs. Then call this function.
|
||||
receiveMessage (sender, m) {
|
||||
if (m.type === "sync step 1") {
|
||||
// TODO: make transaction, stream the ops
|
||||
var ops = yield* this.os.getOperations(m.stateVector);
|
||||
// TODO: compare against m.sv!
|
||||
var sv = yield* this.getStateVector();
|
||||
this.send (sender, {
|
||||
type: "sync step 2"
|
||||
os: ops,
|
||||
stateVector: sv
|
||||
});
|
||||
this.syncingClients.push(sender);
|
||||
setTimeout(()=>{
|
||||
this.syncingClients = this.syncingClients.filter(function(client){
|
||||
return client !== sender;
|
||||
});
|
||||
this.send(sender, {
|
||||
type: "sync done"
|
||||
})
|
||||
}, this.syncingClientDuration);
|
||||
} else if (m.type === "sync step 2") {
|
||||
var ops = this.os.getOperations(m.stateVector);
|
||||
this.broadcast {
|
||||
type: "update",
|
||||
ops: ops
|
||||
}
|
||||
} else if (m.type === "sync done") {
|
||||
this.connections[sender].isSynced = true;
|
||||
this.findNextSyncTarget();
|
||||
}
|
||||
} else if (m.type === "update") {
|
||||
for (var client of this.syncingClients) {
|
||||
this.send(client, m);
|
||||
}
|
||||
this.os.apply(m.ops);
|
||||
}
|
||||
}
|
||||
// Currently, the HB encodes operations as JSON. For the moment I want to keep it
|
||||
// that way. Maybe we support encoding in the HB as XML in the future, but for now I don't want
|
||||
// too much overhead. Y is very likely to get changed a lot in the future
|
||||
//
|
||||
// Because we don't want to encode JSON as string (with character escaping, wich makes it pretty much unreadable)
|
||||
// we encode the JSON as XML.
|
||||
//
|
||||
// When the HB support encoding as XML, the format should look pretty much like this.
|
||||
//
|
||||
// does not support primitive values as array elements
|
||||
// expects an ltx (less than xml) object
|
||||
parseMessageFromXml (m) {
|
||||
function parseArray (node) {
|
||||
for (var n of node.children){
|
||||
if (n.getAttribute("isArray") === "true") {
|
||||
return parseArray(n);
|
||||
} else {
|
||||
return parseObject(n);
|
||||
}
|
||||
}
|
||||
}
|
||||
function parseObject (node) {
|
||||
var json = {};
|
||||
for (name in node.attrs) {
|
||||
var value = node.attrs[name];
|
||||
var int = parseInt(value);
|
||||
if (isNaN(int) or (""+int) !== value){
|
||||
json[name] = value;
|
||||
} else {
|
||||
json[name] = int;
|
||||
}
|
||||
}
|
||||
for (n in node.children){
|
||||
var name = n.name;
|
||||
if (n.getAttribute("isArray") === "true") {
|
||||
json[name] = parseArray(n);
|
||||
} else {
|
||||
json[name] = parseObject(n);
|
||||
}
|
||||
}
|
||||
return json;
|
||||
}
|
||||
parseObject(node);
|
||||
}
|
||||
// encode message in xml
|
||||
// we use string because Strophe only accepts an "xml-string"..
|
||||
// So {a:4,b:{c:5}} will look like
|
||||
// <y a="4">
|
||||
// <b c="5"></b>
|
||||
// </y>
|
||||
// m - ltx element
|
||||
// json - Object
|
||||
encodeMessageToXml (m, json) {
|
||||
// attributes is optional
|
||||
function encodeObject (m, json) {
|
||||
for (name in json) {
|
||||
var value = json[name];
|
||||
if (name == null) {
|
||||
// nop
|
||||
} else if (value.constructor === Object) {
|
||||
encodeObject(m.c(name), value);
|
||||
} else if (value.constructor === Array) {
|
||||
encodeArray(m.c(name), value);
|
||||
} else {
|
||||
m.setAttribute(name, value);
|
||||
}
|
||||
}
|
||||
}
|
||||
function encodeArray (m, array) {
|
||||
m.setAttribute("isArray", "true");
|
||||
for (var e of array) {
|
||||
if (e.constructor === Object) {
|
||||
encodeObject(m.c("array-element"), e);
|
||||
} else {
|
||||
encodeArray(m.c("array-element"), e);
|
||||
}
|
||||
}
|
||||
}
|
||||
if (json.constructor === Object) {
|
||||
encodeObject(m.c("y", {xmlns:"http://y.ninja/connector-stanza"}), json);
|
||||
} else if (json.constructor === Array) {
|
||||
encodeArray(m.c("y", {xmlns:"http://y.ninja/connector-stanza"}), json);
|
||||
} else {
|
||||
throw new Error("I can't encode this json!");
|
||||
}
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user