Simplify the initial connection protocol.

The ServerConnection.connect method is no longer async,
we rely on the onconnected callback only.  The onconnected
callback is now only called after the initial handshake
completes.  There is a new onerror callback.
This commit is contained in:
Juliusz Chroboczek
2024-06-10 19:41:23 +02:00
parent 58934a1a46
commit 7151fad149
3 changed files with 205 additions and 172 deletions
+186 -157
View File
@@ -152,6 +152,13 @@ function ServerConnection() {
* @type{(this: ServerConnection) => void}
*/
this.onconnected = null;
/**
* onerror is called whenever a fatal error occurs. The stream will
* then be closed, and onclose called normally.
*
* @type{(this: ServerConnection, error: unknown) => void}
*/
this.onerror = null;
/**
* onclose is called when the connection is closed
*
@@ -263,6 +270,19 @@ ServerConnection.prototype.close = function() {
this.socket = null;
};
/**
* error forcibly closes a server connection and invokes the onerror
* callback. The onclose callback will be invoked when the connection
* is effectively closed.
*
* @param {any} e
*/
ServerConnection.prototype.error = function(e) {
if(this.onerror)
this.onerror.call(this, e);
this.close();
};
/**
* send sends a message to the server.
* @param {message} m - the message to send.
@@ -279,191 +299,200 @@ ServerConnection.prototype.send = function(m) {
* connect connects to the server.
*
* @param {string} url - The URL to connect to.
* @returns {Promise<ServerConnection>}
* @function
*/
ServerConnection.prototype.connect = async function(url) {
ServerConnection.prototype.connect = function(url) {
let sc = this;
if(sc.socket) {
sc.socket.close(1000, 'Reconnecting');
sc.socket = null;
}
if(sc.socket)
throw new Error("Attempting to connect stale connection");
sc.socket = new WebSocket(url);
return await new Promise((resolve, reject) => {
this.socket.onerror = function(e) {
reject(e);
};
this.socket.onopen = function(e) {
this.socket.onerror = function(e) {
if(sc.onerror)
sc.onerror.call(sc, new Error('Socket error: ' + e));
};
this.socket.onopen = function(e) {
try {
sc.send({
type: 'handshake',
version: ['2'],
id: sc.id,
});
} catch(e) {
sc.error(e);
return;
}
};
this.socket.onclose = function(e) {
sc.permissions = [];
for(let id in sc.up) {
let c = sc.up[id];
c.close();
}
for(let id in sc.down) {
let c = sc.down[id];
c.close();
}
for(let id in sc.users) {
delete(sc.users[id]);
if(sc.onuser)
sc.onuser.call(sc, id, 'delete');
}
if(sc.group && sc.onjoined)
sc.onjoined.call(sc, 'leave', sc.group, [], {}, {}, '', '');
sc.group = null;
sc.username = null;
if(sc.onclose)
sc.onclose.call(sc, e.code, e.reason);
};
this.socket.onmessage = function(e) {
let m;
try {
m = JSON.parse(e.data);
} catch(e) {
sc.error(e);
return;
}
if(m.type !== 'handshake' && !sc.version) {
sc.error(new Error("Server didn't send handshake"));
return;
}
switch(m.type) {
case 'handshake': {
if((m.version instanceof Array) && m.version.includes('2')) {
sc.version = '2';
} else {
sc.version = null;
sc.error(new Error(`Unknown protocol version ${m.version}`));
return;
}
if(sc.onconnected)
sc.onconnected.call(sc);
resolve(sc);
};
this.socket.onclose = function(e) {
sc.permissions = [];
for(let id in sc.up) {
let c = sc.up[id];
c.close();
}
for(let id in sc.down) {
let c = sc.down[id];
c.close();
}
for(let id in sc.users) {
delete(sc.users[id]);
if(sc.onuser)
sc.onuser.call(sc, id, 'delete');
}
if(sc.group && sc.onjoined)
sc.onjoined.call(sc, 'leave', sc.group, [], {}, {}, '', '');
sc.group = null;
sc.username = null;
if(sc.onclose)
sc.onclose.call(sc, e.code, e.reason);
reject(new Error('websocket close ' + e.code + ' ' + e.reason));
};
this.socket.onmessage = function(e) {
let m = JSON.parse(e.data);
switch(m.type) {
case 'handshake': {
if((m.version instanceof Array) && m.version.includes('2')) {
sc.version = '2';
} else {
sc.version = null;
console.error(`Unknown protocol version ${m.version}`);
throw new Error(`Unknown protocol version ${m.version}`);
break;
}
case 'offer':
sc.gotOffer(m.id, m.label, m.source, m.username,
m.sdp, m.replace);
break;
case 'answer':
sc.gotAnswer(m.id, m.sdp);
break;
case 'renegotiate':
sc.gotRenegotiate(m.id);
break;
case 'close':
sc.gotClose(m.id);
break;
case 'abort':
sc.gotAbort(m.id);
break;
case 'ice':
sc.gotRemoteIce(m.id, m.candidate);
break;
case 'joined':
if(m.kind === 'leave' || m.kind === 'fail') {
for(let id in sc.users) {
delete(sc.users[id]);
if(sc.onuser)
sc.onuser.call(sc, id, 'delete');
}
break;
}
case 'offer':
sc.gotOffer(m.id, m.label, m.source, m.username,
m.sdp, m.replace);
break;
case 'answer':
sc.gotAnswer(m.id, m.sdp);
break;
case 'renegotiate':
sc.gotRenegotiate(m.id);
break;
case 'close':
sc.gotClose(m.id);
break;
case 'abort':
sc.gotAbort(m.id);
break;
case 'ice':
sc.gotRemoteIce(m.id, m.candidate);
break;
case 'joined':
if(m.kind === 'leave' || m.kind === 'fail') {
for(let id in sc.users) {
delete(sc.users[id]);
if(sc.onuser)
sc.onuser.call(sc, id, 'delete');
}
sc.username = null;
sc.permissions = [];
sc.rtcConfiguration = null;
} else if(m.kind === 'join' || m.kind == 'change') {
if(m.kind === 'join' && sc.group) {
throw new Error('Joined multiple groups');
} else if(m.kind === 'change' && m.group != sc.group) {
console.warn('join(change) for inconsistent group');
break;
}
sc.group = m.group;
sc.username = m.username;
sc.permissions = m.permissions || [];
sc.rtcConfiguration = m.rtcConfiguration || null;
sc.username = null;
sc.permissions = [];
sc.rtcConfiguration = null;
} else if(m.kind === 'join' || m.kind == 'change') {
if(m.kind === 'join' && sc.group) {
throw new Error('Joined multiple groups');
} else if(m.kind === 'change' && m.group != sc.group) {
console.warn('join(change) for inconsistent group');
break;
}
if(sc.onjoined)
sc.onjoined.call(sc, m.kind, m.group,
m.permissions || [],
m.status, m.data,
m.error || null, m.value || null);
sc.group = m.group;
sc.username = m.username;
sc.permissions = m.permissions || [];
sc.rtcConfiguration = m.rtcConfiguration || null;
}
if(sc.onjoined)
sc.onjoined.call(sc, m.kind, m.group,
m.permissions || [],
m.status, m.data,
m.error || null, m.value || null);
break;
case 'user':
switch(m.kind) {
case 'add':
if(m.id in sc.users)
console.warn(`Duplicate user ${m.id} ${m.username}`);
sc.users[m.id] = {
username: m.username,
permissions: m.permissions || [],
data: m.data || {},
streams: {},
};
break;
case 'user':
switch(m.kind) {
case 'add':
if(m.id in sc.users)
console.warn(`Duplicate user ${m.id} ${m.username}`);
case 'change':
if(!(m.id in sc.users)) {
console.warn(`Unknown user ${m.id} ${m.username}`);
sc.users[m.id] = {
username: m.username,
permissions: m.permissions || [],
data: m.data || {},
streams: {},
};
break;
case 'change':
if(!(m.id in sc.users)) {
console.warn(`Unknown user ${m.id} ${m.username}`);
sc.users[m.id] = {
username: m.username,
permissions: m.permissions || [],
data: m.data || {},
streams: {},
};
} else {
sc.users[m.id].username = m.username;
sc.users[m.id].permissions = m.permissions || [];
sc.users[m.id].data = m.data || {};
}
break;
case 'delete':
if(!(m.id in sc.users))
console.warn(`Unknown user ${m.id} ${m.username}`);
for(let t in sc.transferredFiles) {
let f = sc.transferredFiles[t];
if(f.userid === m.id)
f.fail('user has gone away');
}
delete(sc.users[m.id]);
break;
default:
console.warn(`Unknown user action ${m.kind}`);
return;
} else {
sc.users[m.id].username = m.username;
sc.users[m.id].permissions = m.permissions || [];
sc.users[m.id].data = m.data || {};
}
if(sc.onuser)
sc.onuser.call(sc, m.id, m.kind);
break;
case 'chat':
case 'chathistory':
if(sc.onchat)
sc.onchat.call(
sc, m.source, m.dest, m.username, parseTime(m.time),
m.privileged, m.type === 'chathistory', m.kind,
'' + m.value,
);
break;
case 'usermessage':
if(m.kind === 'filetransfer')
sc.fileTransfer(m.source, m.username, m.value);
else if(sc.onusermessage)
sc.onusermessage.call(
sc, m.source, m.dest, m.username, parseTime(m.time),
m.privileged, m.kind, m.error, m.value,
);
break;
case 'ping':
sc.send({
type: 'pong',
});
break;
case 'pong':
/* nothing */
case 'delete':
if(!(m.id in sc.users))
console.warn(`Unknown user ${m.id} ${m.username}`);
for(let t in sc.transferredFiles) {
let f = sc.transferredFiles[t];
if(f.userid === m.id)
f.fail('user has gone away');
}
delete(sc.users[m.id]);
break;
default:
console.warn('Unexpected server message', m.type);
console.warn(`Unknown user action ${m.kind}`);
return;
}
};
});
if(sc.onuser)
sc.onuser.call(sc, m.id, m.kind);
break;
case 'chat':
case 'chathistory':
if(sc.onchat)
sc.onchat.call(
sc, m.source, m.dest, m.username, parseTime(m.time),
m.privileged, m.type === 'chathistory', m.kind,
'' + m.value,
);
break;
case 'usermessage':
if(m.kind === 'filetransfer')
sc.fileTransfer(m.source, m.username, m.value);
else if(sc.onusermessage)
sc.onusermessage.call(
sc, m.source, m.dest, m.username, parseTime(m.time),
m.privileged, m.kind, m.error, m.value,
);
break;
case 'ping':
sc.send({
type: 'pong',
});
break;
case 'pong':
/* nothing */
break;
default:
console.warn('Unexpected server message', m.type);
return;
}
};
};
/**