make this a proper esm module
This commit is contained in:
Kevin Jahns
290
bin/utils.cjs
Normal file
290
bin/utils.cjs
Normal file
@@ -0,0 +1,290 @@
|
||||
const Y = require('yjs')
|
||||
const syncProtocol = require('y-protocols/sync')
|
||||
const awarenessProtocol = require('y-protocols/awareness')
|
||||
|
||||
const encoding = require('lib0/encoding')
|
||||
const decoding = require('lib0/decoding')
|
||||
const map = require('lib0/map')
|
||||
|
||||
const debounce = require('lodash.debounce')
|
||||
|
||||
const callbackHandler = require('./callback.cjs').callbackHandler
|
||||
const isCallbackSet = require('./callback.cjs').isCallbackSet
|
||||
|
||||
const CALLBACK_DEBOUNCE_WAIT = parseInt(process.env.CALLBACK_DEBOUNCE_WAIT || '2000')
|
||||
const CALLBACK_DEBOUNCE_MAXWAIT = parseInt(process.env.CALLBACK_DEBOUNCE_MAXWAIT || '10000')
|
||||
|
||||
const wsReadyStateConnecting = 0
|
||||
const wsReadyStateOpen = 1
|
||||
const wsReadyStateClosing = 2 // eslint-disable-line
|
||||
const wsReadyStateClosed = 3 // eslint-disable-line
|
||||
|
||||
// disable gc when using snapshots!
|
||||
const gcEnabled = process.env.GC !== 'false' && process.env.GC !== '0'
|
||||
const persistenceDir = process.env.YPERSISTENCE
|
||||
/**
|
||||
* @type {{bindState: function(string,WSSharedDoc):void, writeState:function(string,WSSharedDoc):Promise<any>, provider: any}|null}
|
||||
*/
|
||||
let persistence = null
|
||||
if (typeof persistenceDir === 'string') {
|
||||
console.info('Persisting documents to "' + persistenceDir + '"')
|
||||
// @ts-ignore
|
||||
const LeveldbPersistence = require('y-leveldb').LeveldbPersistence
|
||||
const ldb = new LeveldbPersistence(persistenceDir)
|
||||
persistence = {
|
||||
provider: ldb,
|
||||
bindState: async (docName, ydoc) => {
|
||||
const persistedYdoc = await ldb.getYDoc(docName)
|
||||
const newUpdates = Y.encodeStateAsUpdate(ydoc)
|
||||
ldb.storeUpdate(docName, newUpdates)
|
||||
Y.applyUpdate(ydoc, Y.encodeStateAsUpdate(persistedYdoc))
|
||||
ydoc.on('update', update => {
|
||||
ldb.storeUpdate(docName, update)
|
||||
})
|
||||
},
|
||||
writeState: async (docName, ydoc) => {}
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* @param {{bindState: function(string,WSSharedDoc):void,
|
||||
* writeState:function(string,WSSharedDoc):Promise<any>,provider:any}|null} persistence_
|
||||
*/
|
||||
exports.setPersistence = persistence_ => {
|
||||
persistence = persistence_
|
||||
}
|
||||
|
||||
/**
|
||||
* @return {null|{bindState: function(string,WSSharedDoc):void,
|
||||
* writeState:function(string,WSSharedDoc):Promise<any>}|null} used persistence layer
|
||||
*/
|
||||
exports.getPersistence = () => persistence
|
||||
|
||||
/**
|
||||
* @type {Map<string,WSSharedDoc>}
|
||||
*/
|
||||
const docs = new Map()
|
||||
// exporting docs so that others can use it
|
||||
exports.docs = docs
|
||||
|
||||
const messageSync = 0
|
||||
const messageAwareness = 1
|
||||
// const messageAuth = 2
|
||||
|
||||
/**
|
||||
* @param {Uint8Array} update
|
||||
* @param {any} _origin
|
||||
* @param {WSSharedDoc} doc
|
||||
* @param {any} _tr
|
||||
*/
|
||||
const updateHandler = (update, _origin, doc, _tr) => {
|
||||
const encoder = encoding.createEncoder()
|
||||
encoding.writeVarUint(encoder, messageSync)
|
||||
syncProtocol.writeUpdate(encoder, update)
|
||||
const message = encoding.toUint8Array(encoder)
|
||||
doc.conns.forEach((_, conn) => send(doc, conn, message))
|
||||
}
|
||||
|
||||
class WSSharedDoc extends Y.Doc {
|
||||
/**
|
||||
* @param {string} name
|
||||
*/
|
||||
constructor (name) {
|
||||
super({ gc: gcEnabled })
|
||||
this.name = name
|
||||
/**
|
||||
* Maps from conn to set of controlled user ids. Delete all user ids from awareness when this conn is closed
|
||||
* @type {Map<Object, Set<number>>}
|
||||
*/
|
||||
this.conns = new Map()
|
||||
/**
|
||||
* @type {awarenessProtocol.Awareness}
|
||||
*/
|
||||
this.awareness = new awarenessProtocol.Awareness(this)
|
||||
this.awareness.setLocalState(null)
|
||||
/**
|
||||
* @param {{ added: Array<number>, updated: Array<number>, removed: Array<number> }} changes
|
||||
* @param {Object | null} conn Origin is the connection that made the change
|
||||
*/
|
||||
const awarenessChangeHandler = ({ added, updated, removed }, conn) => {
|
||||
const changedClients = added.concat(updated, removed)
|
||||
if (conn !== null) {
|
||||
const connControlledIDs = /** @type {Set<number>} */ (this.conns.get(conn))
|
||||
if (connControlledIDs !== undefined) {
|
||||
added.forEach(clientID => { connControlledIDs.add(clientID) })
|
||||
removed.forEach(clientID => { connControlledIDs.delete(clientID) })
|
||||
}
|
||||
}
|
||||
// broadcast awareness update
|
||||
const encoder = encoding.createEncoder()
|
||||
encoding.writeVarUint(encoder, messageAwareness)
|
||||
encoding.writeVarUint8Array(encoder, awarenessProtocol.encodeAwarenessUpdate(this.awareness, changedClients))
|
||||
const buff = encoding.toUint8Array(encoder)
|
||||
this.conns.forEach((_, c) => {
|
||||
send(this, c, buff)
|
||||
})
|
||||
}
|
||||
this.awareness.on('update', awarenessChangeHandler)
|
||||
this.on('update', /** @type {any} */ (updateHandler))
|
||||
if (isCallbackSet) {
|
||||
this.on('update', debounce(
|
||||
callbackHandler,
|
||||
CALLBACK_DEBOUNCE_WAIT,
|
||||
{ maxWait: CALLBACK_DEBOUNCE_MAXWAIT }
|
||||
))
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
exports.WSSharedDoc = WSSharedDoc
|
||||
|
||||
/**
|
||||
* Gets a Y.Doc by name, whether in memory or on disk
|
||||
*
|
||||
* @param {string} docname - the name of the Y.Doc to find or create
|
||||
* @param {boolean} gc - whether to allow gc on the doc (applies only when created)
|
||||
* @return {WSSharedDoc}
|
||||
*/
|
||||
const getYDoc = (docname, gc = true) => map.setIfUndefined(docs, docname, () => {
|
||||
const doc = new WSSharedDoc(docname)
|
||||
doc.gc = gc
|
||||
if (persistence !== null) {
|
||||
persistence.bindState(docname, doc)
|
||||
}
|
||||
docs.set(docname, doc)
|
||||
return doc
|
||||
})
|
||||
|
||||
exports.getYDoc = getYDoc
|
||||
|
||||
/**
|
||||
* @param {any} conn
|
||||
* @param {WSSharedDoc} doc
|
||||
* @param {Uint8Array} message
|
||||
*/
|
||||
const messageListener = (conn, doc, message) => {
|
||||
try {
|
||||
const encoder = encoding.createEncoder()
|
||||
const decoder = decoding.createDecoder(message)
|
||||
const messageType = decoding.readVarUint(decoder)
|
||||
switch (messageType) {
|
||||
case messageSync:
|
||||
encoding.writeVarUint(encoder, messageSync)
|
||||
syncProtocol.readSyncMessage(decoder, encoder, doc, conn)
|
||||
|
||||
// If the `encoder` only contains the type of reply message and no
|
||||
// message, there is no need to send the message. When `encoder` only
|
||||
// contains the type of reply, its length is 1.
|
||||
if (encoding.length(encoder) > 1) {
|
||||
send(doc, conn, encoding.toUint8Array(encoder))
|
||||
}
|
||||
break
|
||||
case messageAwareness: {
|
||||
awarenessProtocol.applyAwarenessUpdate(doc.awareness, decoding.readVarUint8Array(decoder), conn)
|
||||
break
|
||||
}
|
||||
}
|
||||
} catch (err) {
|
||||
console.error(err)
|
||||
// @ts-ignore
|
||||
doc.emit('error', [err])
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* @param {WSSharedDoc} doc
|
||||
* @param {any} conn
|
||||
*/
|
||||
const closeConn = (doc, conn) => {
|
||||
if (doc.conns.has(conn)) {
|
||||
/**
|
||||
* @type {Set<number>}
|
||||
*/
|
||||
// @ts-ignore
|
||||
const controlledIds = doc.conns.get(conn)
|
||||
doc.conns.delete(conn)
|
||||
awarenessProtocol.removeAwarenessStates(doc.awareness, Array.from(controlledIds), null)
|
||||
if (doc.conns.size === 0 && persistence !== null) {
|
||||
// if persisted, we store state and destroy ydocument
|
||||
persistence.writeState(doc.name, doc).then(() => {
|
||||
doc.destroy()
|
||||
})
|
||||
docs.delete(doc.name)
|
||||
}
|
||||
}
|
||||
conn.close()
|
||||
}
|
||||
|
||||
/**
|
||||
* @param {WSSharedDoc} doc
|
||||
* @param {any} conn
|
||||
* @param {Uint8Array} m
|
||||
*/
|
||||
const send = (doc, conn, m) => {
|
||||
if (conn.readyState !== wsReadyStateConnecting && conn.readyState !== wsReadyStateOpen) {
|
||||
closeConn(doc, conn)
|
||||
}
|
||||
try {
|
||||
conn.send(m, /** @param {any} err */ err => { err != null && closeConn(doc, conn) })
|
||||
} catch (e) {
|
||||
closeConn(doc, conn)
|
||||
}
|
||||
}
|
||||
|
||||
const pingTimeout = 30000
|
||||
|
||||
/**
|
||||
* @param {any} conn
|
||||
* @param {any} req
|
||||
* @param {any} opts
|
||||
*/
|
||||
exports.setupWSConnection = (conn, req, { docName = req.url.slice(1).split('?')[0], gc = true } = {}) => {
|
||||
conn.binaryType = 'arraybuffer'
|
||||
// get doc, initialize if it does not exist yet
|
||||
const doc = getYDoc(docName, gc)
|
||||
doc.conns.set(conn, new Set())
|
||||
// listen and reply to events
|
||||
conn.on('message', /** @param {ArrayBuffer} message */ message => messageListener(conn, doc, new Uint8Array(message)))
|
||||
|
||||
// Check if connection is still alive
|
||||
let pongReceived = true
|
||||
const pingInterval = setInterval(() => {
|
||||
if (!pongReceived) {
|
||||
if (doc.conns.has(conn)) {
|
||||
closeConn(doc, conn)
|
||||
}
|
||||
clearInterval(pingInterval)
|
||||
} else if (doc.conns.has(conn)) {
|
||||
pongReceived = false
|
||||
try {
|
||||
conn.ping()
|
||||
} catch (e) {
|
||||
closeConn(doc, conn)
|
||||
clearInterval(pingInterval)
|
||||
}
|
||||
}
|
||||
}, pingTimeout)
|
||||
conn.on('close', () => {
|
||||
closeConn(doc, conn)
|
||||
clearInterval(pingInterval)
|
||||
})
|
||||
conn.on('pong', () => {
|
||||
pongReceived = true
|
||||
})
|
||||
// put the following in a variables in a block so the interval handlers don't keep in in
|
||||
// scope
|
||||
{
|
||||
// send sync step 1
|
||||
const encoder = encoding.createEncoder()
|
||||
encoding.writeVarUint(encoder, messageSync)
|
||||
syncProtocol.writeSyncStep1(encoder, doc)
|
||||
send(doc, conn, encoding.toUint8Array(encoder))
|
||||
const awarenessStates = doc.awareness.getStates()
|
||||
if (awarenessStates.size > 0) {
|
||||
const encoder = encoding.createEncoder()
|
||||
encoding.writeVarUint(encoder, messageAwareness)
|
||||
encoding.writeVarUint8Array(encoder, awarenessProtocol.encodeAwarenessUpdate(doc.awareness, Array.from(awarenessStates.keys())))
|
||||
send(doc, conn, encoding.toUint8Array(encoder))
|
||||
}
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user