(function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(require,module,exports){
/* @flow */
'use strict'
module.exports = function (Y/* :any */) {
class AbstractConnector {
/* ::
y: YConfig;
role: SyncRole;
connections: Object;
isSynced: boolean;
userEventListeners: Array<Function>;
whenSyncedListeners: Array<Function>;
currentSyncTarget: ?UserId;
syncingClients: Array<UserId>;
forwardToSyncingClients: boolean;
debug: boolean;
broadcastedHB: boolean;
syncStep2: Promise;
userId: UserId;
send: Function;
broadcast: Function;
*/
/*
opts contains the following information:
role : String Role of this client ("master" or "slave")
userId : String Uniquely defines the user.
debug: Boolean Whether to print debug messages (optional)
*/
constructor (y, opts) {
this.y = y
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.y.db.forwardAppliedOperations = opts.forwardAppliedOperations || false
this.role = opts.role
this.connections = {}
this.isSynced = false
this.userEventListeners = []
this.whenSyncedListeners = []
this.currentSyncTarget = null
this.syncingClients = []
this.forwardToSyncingClients = opts.forwardToSyncingClients !== false
this.debug = opts.debug === true
this.broadcastedHB = false
this.syncStep2 = Promise.resolve()
this.broadcastOpBuffer = []
}
reconnect () {
}
disconnect () {
this.connections = {}
this.isSynced = false
this.currentSyncTarget = null
this.broadcastedHB = false
this.syncingClients = []
this.whenSyncedListeners = []
return this.y.db.stopGarbageCollector()
}
setUserId (userId) {
if (this.userId == null) {
this.userId = userId
return this.y.db.setUserId(userId)
} else {
return null
}
}
onUserEvent (f) {
this.userEventListeners.push(f)
}
userLeft (user) {
if (this.connections[user] != null) {
delete this.connections[user]
if (user === this.currentSyncTarget) {
this.currentSyncTarget = null
this.findNextSyncTarget()
}
this.syncingClients = this.syncingClients.filter(function (cli) {
return cli !== user
})
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
})
}
if (this.currentSyncTarget == null) {
this.findNextSyncTarget()
}
}
// Execute a function _when_ we are connected.
// If not connected, wait until connected
whenSynced (f) {
if (this.isSynced) {
f()
} else {
this.whenSyncedListeners.push(f)
}
}
/*
returns false, if there is no sync target
true otherwise
*/
findNextSyncTarget () {
if (this.currentSyncTarget != null || this.isSynced) {
return // "The current sync has not finished!"
}
var syncUser = null
for (var uid in this.connections) {
if (!this.connections[uid].isSynced) {
syncUser = uid
break
}
}
if (syncUser != null) {
var conn = this
this.currentSyncTarget = syncUser
this.y.db.requestTransaction(function *() {
var stateSet = yield* this.getStateSet()
var deleteSet = yield* this.getDeleteSet()
conn.send(syncUser, {
type: 'sync step 1',
stateSet: stateSet,
deleteSet: deleteSet
})
})
} else {
this.isSynced = true
// call when synced listeners
for (var f of this.whenSyncedListeners) {
f()
}
this.whenSyncedListeners = []
this.y.db.requestTransaction(function *() {
yield* this.garbageCollectAfterSync()
})
}
}
send (uid, message) {
if (this.debug) {
console.log(`send ${this.userId} -> ${uid}: ${message.type}`, message) // eslint-disable-line
}
}
/*
Buffer operations, and broadcast them when ready.
*/
broadcastOps (ops) {
ops = ops.map(function (op) {
return Y.Struct[op.struct].encode(op)
})
var self = this
function broadcastOperations () {
if (self.broadcastOpBuffer.length > 0) {
self.broadcast({
type: 'update',
ops: self.broadcastOpBuffer
})
self.broadcastOpBuffer = []
}
}
if (this.broadcastOpBuffer.length === 0) {
this.broadcastOpBuffer = ops
if (this.y.db.transactionInProgress) {
this.y.db.whenTransactionsFinished().then(broadcastOperations)
} else {
setTimeout(broadcastOperations, 0)
}
} else {
this.broadcastOpBuffer = this.broadcastOpBuffer.concat(ops)
}
}
/*
You received a raw message, and you know that it is intended for Yjs. Then call this function.
*/
receiveMessage (sender/* :UserId */, message/* :Message */) {
if (sender === this.userId) {
return
}
if (this.debug) {
console.log(`receive ${sender} -> ${this.userId}: ${message.type}`, JSON.parse(JSON.stringify(message))) // eslint-disable-line
}
if (message.type === 'sync step 1') {
// TODO: make transaction, stream the ops
let conn = this
let m = message
this.y.db.requestTransaction(function *() {
var currentStateSet = yield* this.getStateSet()
yield* this.applyDeleteSet(m.deleteSet)
var ds = yield* this.getDeleteSet()
var ops = yield* this.getOperations(m.stateSet)
conn.send(sender, {
type: 'sync step 2',
os: ops,
stateSet: currentStateSet,
deleteSet: ds
})
if (this.forwardToSyncingClients) {
conn.syncingClients.push(sender)
setTimeout(function () {
conn.syncingClients = conn.syncingClients.filter(function (cli) {
return cli !== sender
})
conn.send(sender, {
type: 'sync done'
})
}, 5000) // TODO: conn.syncingClientDuration)
} else {
conn.send(sender, {
type: 'sync done'
})
}
conn._setSyncedWith(sender)
})
} else if (message.type === 'sync step 2') {
let conn = this
var broadcastHB = !this.broadcastedHB
this.broadcastedHB = true
var db = this.y.db
var defer = {}
defer.promise = new Promise(function (resolve) {
defer.resolve = resolve
})
this.syncStep2 = defer.promise
let m /* :MessageSyncStep2 */ = message
db.requestTransaction(function * () {
yield* this.applyDeleteSet(m.deleteSet)
this.store.apply(m.os)
db.requestTransaction(function * () {
var ops = yield* this.getOperations(m.stateSet)
if (ops.length > 0) {
if (!broadcastHB) { // TODO: consider to broadcast here..
conn.send(sender, {
type: 'update',
ops: ops
})
} else {
// broadcast only once!
conn.broadcastOps(ops)
}
}
defer.resolve()
})
})
} else if (message.type === 'sync done') {
var self = this
this.syncStep2.then(function () {
self._setSyncedWith(sender)
})
} else if (message.type === 'update') {
if (this.forwardToSyncingClients) {
for (var client of this.syncingClients) {
this.send(client, message)
}
}
if (this.y.db.forwardAppliedOperations) {
var delops = message.ops.filter(function (o) {
return o.struct === 'Delete'
})
if (delops.length > 0) {
this.broadcastOps(delops)
}
}
this.y.db.apply(message.ops)
}
}
_setSyncedWith (user) {
var conn = this.connections[user]
if (conn != null) {
conn.isSynced = true
}
if (user === this.currentSyncTarget) {
this.currentSyncTarget = null
this.findNextSyncTarget()
}
}
/*
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/* :any */) {
function parseArray (node) {
for (var n of node.children) {
if (n.getAttribute('isArray') === 'true') {
return parseArray(n)
} else {
return parseObject(n)
}
}
}
function parseObject (node/* :any */) {
var json = {}
for (var attrName in node.attrs) {
var value = node.attrs[attrName]
var int = parseInt(value, 10)
if (isNaN(int) || ('' + int) !== value) {
json[attrName] = value
} else {
json[attrName] = int
}
}
for (var n/* :any */ in node.children) {
var name = n.name
if (n.getAttribute('isArray') === 'true') {
json[name] = parseArray(n)
} else {
json[name] = parseObject(n)
}
}
return json
}
parseObject(m)
}
/*
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 (msg, obj) {
// attributes is optional
function encodeObject (m, json) {
for (var 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 (obj.constructor === Object) {
encodeObject(msg.c('y', { xmlns: 'http://y.ninja/connector-stanza' }), obj)
} else if (obj.constructor === Array) {
encodeArray(msg.c('y', { xmlns: 'http://y.ninja/connector-stanza' }), obj)
} else {
throw new Error("I can't encode this json!")
}
}
}
Y.AbstractConnector = AbstractConnector
}
},{}],2:[function(require,module,exports){
/* global getRandom, async */
'use strict'
module.exports = function (Y) {
var globalRoom = {
users: {},
buffers: {},
removeUser: function (user) {
for (var i in this.users) {
this.users[i].userLeft(user)
}
delete this.users[user]
delete this.buffers[user]
},
addUser: function (connector) {
this.users[connector.userId] = connector
this.buffers[connector.userId] = []
for (var uname in this.users) {
if (uname !== connector.userId) {
var u = this.users[uname]
u.userJoined(connector.userId, 'master')
connector.userJoined(u.userId, 'master')
}
}
},
whenTransactionsFinished: function () {
var ps = []
for (var name in this.users) {
ps.push(this.users[name].y.db.whenTransactionsFinished())
}
return Promise.all(ps)
},
flushOne: function flushOne () {
var bufs = []
for (var i in globalRoom.buffers) {
if (globalRoom.buffers[i].length > 0) {
bufs.push(i)
}
}
if (bufs.length > 0) {
var userId = getRandom(bufs)
var m = globalRoom.buffers[userId].shift()
var user = globalRoom.users[userId]
user.receiveMessage(m[0], m[1])
return user.y.db.whenTransactionsFinished()
} else {
return false
}
},
flushAll: function () {
return new Promise(function (resolve) {
// flushes may result in more created operations,
// flush until there is nothing more to flush
function nextFlush () {
var c = globalRoom.flushOne()
if (c) {
while (c) {
c = globalRoom.flushOne()
}
globalRoom.whenTransactionsFinished().then(nextFlush)
} else {
setTimeout(function () {
var c = globalRoom.flushOne()
if (c) {
c.then(function () {
globalRoom.whenTransactionsFinished().then(nextFlush)
})
} else {
resolve()
}
}, 10)
}
}
globalRoom.whenTransactionsFinished().then(nextFlush)
})
}
}
Y.utils.globalRoom = globalRoom
var userIdCounter = 0
class Test extends Y.AbstractConnector {
constructor (y, options) {
if (options === undefined) {
throw new Error('Options must not be undefined!')
}
options.role = 'master'
options.forwardToSyncingClients = false
super(y, options)
this.setUserId((userIdCounter++) + '').then(() => {
globalRoom.addUser(this)
})
this.globalRoom = globalRoom
this.syncingClientDuration = 0
}
receiveMessage (sender, m) {
super.receiveMessage(sender, JSON.parse(JSON.stringify(m)))
}
send (userId, message) {
var buffer = globalRoom.buffers[userId]
if (buffer != null) {
buffer.push(JSON.parse(JSON.stringify([this.userId, message])))
}
}
broadcast (message) {
for (var key in globalRoom.buffers) {
globalRoom.buffers[key].push(JSON.parse(JSON.stringify([this.userId, message])))
}
}
isDisconnected () {
return globalRoom.users[this.userId] == null
}
reconnect () {
if (this.isDisconnected()) {
globalRoom.addUser(this)
super.reconnect()
}
return Y.utils.globalRoom.flushAll()
}
disconnect () {
if (!this.isDisconnected()) {
globalRoom.removeUser(this.userId)
super.disconnect()
}
return this.y.db.whenTransactionsFinished()
}
flush () {
var self = this
return async(function * () {
while (globalRoom.buffers[self.userId].length > 0) {
var m = globalRoom.buffers[self.userId].shift()
this.receiveMessage(m[0], m[1])
}
yield self.whenTransactionsFinished()
})
}
}
Y.Test = Test
}
},{}],3:[function(require,module,exports){
/* @flow */
'use strict'
module.exports = function (Y /* :any */) {
/*
Partial definition of an OperationStore.
TODO: name it Database, operation store only holds operations.
A database definition must alse define the following methods:
* logTable() (optional)
- show relevant information information in a table
* requestTransaction(makeGen)
- request a transaction
* destroy()
- destroy the database
*/
class AbstractDatabase {
/* ::
y: YConfig;
forwardAppliedOperations: boolean;
listenersById: Object;
listenersByIdExecuteNow: Array<Object>;
listenersByIdRequestPending: boolean;
initializedTypes: Object;
whenUserIdSetListener: ?Function;
waitingTransactions: Array<Transaction>;
transactionInProgress: boolean;
executeOrder: Array<Object>;
gc1: Array<Struct>;
gc2: Array<Struct>;
gcTimeout: number;
gcInterval: any;
garbageCollect: Function;
executeOrder: Array<any>; // for debugging only
userId: UserId;
opClock: number;
transactionsFinished: ?{promise: Promise, resolve: any};
transact: (x: ?Generator) => any;
*/
constructor (y, opts) {
this.y = y
var os = this
this.userId = null
var resolve
this.userIdPromise = new Promise(function (r) {
resolve = r
})
this.userIdPromise.resolve = resolve
// whether to broadcast all applied operations (insert & delete hook)
this.forwardAppliedOperations = false
// E.g. this.listenersById[id] : Array<Listener>
this.listenersById = {}
// Execute the next time a transaction is requested
this.listenersByIdExecuteNow = []
// A transaction is requested
this.listenersByIdRequestPending = false
/* To make things more clear, the following naming conventions:
* ls : we put this.listenersById on ls
* l : Array<Listener>
* id : Id (can't use as property name)
* sid : String (converted from id via JSON.stringify
so we can use it as a property name)
Always remember to first overwrite
a property before you iterate over it!
*/
// TODO: Use ES7 Weak Maps. This way types that are no longer user,
// wont be kept in memory.
this.initializedTypes = {}
this.waitingTransactions = []
this.transactionInProgress = false
this.transactionIsFlushed = false
if (typeof YConcurrency_TestingMode !== 'undefined') {
this.executeOrder = []
}
this.gc1 = [] // first stage
this.gc2 = [] // second stage -> after that, remove the op
this.gcTimeout = opts.gcTimeout || 50000
function garbageCollect () {
return os.whenTransactionsFinished().then(function () {
if (os.gc1.length > 0 || os.gc2.length > 0) {
return new Promise((resolve) => {
os.requestTransaction(function * () {
if (os.y.connector != null && os.y.connector.isSynced) {
for (var i = 0; i < os.gc2.length; i++) {
var oid = os.gc2[i]
yield* this.garbageCollectOperation(oid)
}
os.gc2 = os.gc1
os.gc1 = []
}
// TODO: Use setInterval here instead (when garbageCollect is called several times there will be several timeouts..)
if (os.gcTimeout > 0) {
os.gcInterval = setTimeout(garbageCollect, os.gcTimeout)
}
resolve()
})
})
} else {
// TODO: see above
if (os.gcTimeout > 0) {
os.gcInterval = setTimeout(garbageCollect, os.gcTimeout)
}
return Promise.resolve()
}
})
}
this.garbageCollect = garbageCollect
if (this.gcTimeout > 0) {
garbageCollect()
}
}
addToDebug () {
if (typeof YConcurrency_TestingMode !== 'undefined') {
var command /* :string */ = Array.prototype.map.call(arguments, function (s) {
if (typeof s === 'string') {
return s
} else {
return JSON.stringify(s)
}
}).join('').replace(/"/g, "'").replace(/,/g, ', ').replace(/:/g, ': ')
this.executeOrder.push(command)
}
}
getDebugData () {
console.log(this.executeOrder.join('\n'))
}
stopGarbageCollector () {
var self = this
return new Promise(function (resolve) {
self.requestTransaction(function * () {
var ungc /* :Array<Struct> */ = self.gc1.concat(self.gc2)
self.gc1 = []
self.gc2 = []
for (var i = 0; i < ungc.length; i++) {
var op = yield* this.getOperation(ungc[i])
delete op.gc
yield* this.setOperation(op)
}
resolve()
})
})
}
/*
Try to add to GC.
TODO: rename this function
Rulez:
* Only gc if this user is online
* The most left element in a list must not be gc'd.
=> There is at least one element in the list
returns true iff op was added to GC
*/
addToGarbageCollector (op, left) {
if (
op.gc == null &&
op.deleted === true &&
this.y.connector.isSynced &&
left != null &&
left.deleted === true
) {
op.gc = true
this.gc1.push(op.id)
return true
} else {
return false
}
}
removeFromGarbageCollector (op) {
function filter (o) {
return !Y.utils.compareIds(o, op.id)
}
this.gc1 = this.gc1.filter(filter)
this.gc2 = this.gc2.filter(filter)
delete op.gc
}
* destroy () {
clearInterval(this.gcInterval)
this.gcInterval = null
for (var key in this.initializedTypes) {
var type = this.initializedTypes[key]
if (type._destroy != null) {
type._destroy()
} else {
console.error('The type you included does not provide destroy functionality, it will remain in memory (updating your packages will help).')
}
}
}
setUserId (userId) {
if (!this.userIdPromise.inProgress) {
this.userIdPromise.inProgress = true
var self = this
self.requestTransaction(function * () {
self.userId = userId
var state = yield* this.getState(userId)
self.opClock = state.clock
self.userIdPromise.resolve(userId)
})
}
return this.userIdPromise
}
whenUserIdSet (f) {
this.userIdPromise.then(f)
}
getNextOpId () {
if (this._nextUserId != null) {
return this._nextUserId
} else if (this.userId == null) {
throw new Error('OperationStore not yet initialized!')
} else {
return [this.userId, this.opClock++]
}
}
/*
Apply a list of operations.
* get a transaction
* check whether all Struct.*.requiredOps are in the OS
* check if it is an expected op (otherwise wait for it)
* check if was deleted, apply a delete operation after op was applied
*/
apply (ops) {
for (var i = 0; i < ops.length; i++) {
var o = ops[i]
if (o.id == null || o.id[0] !== this.y.connector.userId) {
var required = Y.Struct[o.struct].requiredOps(o)
this.whenOperationsExist(required, o)
}
}
}
/*
op is executed as soon as every operation requested is available.
Note that Transaction can (and should) buffer requests.
*/
whenOperationsExist (ids, op) {
if (ids.length > 0) {
let listener = {
op: op,
missing: ids.length
}
for (let i = 0; i < ids.length; i++) {
let id = ids[i]
let sid = JSON.stringify(id)
let l = this.listenersById[sid]
if (l == null) {
l = []
this.listenersById[sid] = l
}
l.push(listener)
}
} else {
this.listenersByIdExecuteNow.push({
op: op
})
}
if (this.listenersByIdRequestPending) {
return
}
this.listenersByIdRequestPending = true
var store = this
this.requestTransaction(function * () {
var exeNow = store.listenersByIdExecuteNow
store.listenersByIdExecuteNow = []
var ls = store.listenersById
store.listenersById = {}
store.listenersByIdRequestPending = false
for (let key = 0; key < exeNow.length; key++) {
let o = exeNow[key].op
yield* store.tryExecute.call(this, o)
}
for (var sid in ls) {
var l = ls[sid]
var id = JSON.parse(sid)
var op = yield* this.getOperation(id)
if (op == null) {
store.listenersById[sid] = l
} else {
for (let i = 0; i < l.length; i++) {
let listener = l[i]
let o = listener.op
if (--listener.missing === 0) {
yield* store.tryExecute.call(this, o)
}
}
}
}
})
}
/*
Actually execute an operation, when all expected operations are available.
*/
/* :: // TODO: this belongs somehow to transaction
store: Object;
getOperation: any;
isGarbageCollected: any;
addOperation: any;
whenOperationsExist: any;
*/
* tryExecute (op) {
this.store.addToDebug('yield* this.store.tryExecute.call(this, ', JSON.stringify(op), ')')
if (op.struct === 'Delete') {
yield* Y.Struct.Delete.execute.call(this, op)
yield* this.store.operationAdded(this, op)
} else {
var defined = yield* this.getOperation(op.id)
if (defined == null) {
var isGarbageCollected = yield* this.isGarbageCollected(op.id)
if (!isGarbageCollected) {
yield* Y.Struct[op.struct].execute.call(this, op)
yield* this.addOperation(op)
yield* this.store.operationAdded(this, op)
}
}
}
}
// called by a transaction when an operation is added
* operationAdded (transaction, op) {
if (op.struct === 'Delete') {
var target = yield* transaction.getOperation(op.target)
if (target != null) {
var type = transaction.store.initializedTypes[JSON.stringify(target.parent)]
if (type != null) {
yield* type._changed(transaction, {
struct: 'Delete',
target: op.target
})
}
}
} else {
// increase SS
var o = op
var state = yield* transaction.getState(op.id[0])
while (o != null && o.id[1] === state.clock && op.id[0] === o.id[0]) {
// either its a new operation (1. case), or it is an operation that was deleted, but is not yet in the OS
state.clock++
yield* transaction.checkDeleteStoreForState(state)
o = yield* transaction.os.findNext(o.id)
}
yield* transaction.setState(state)
// notify whenOperation listeners (by id)
var sid = JSON.stringify(op.id)
var l = this.listenersById[sid]
delete this.listenersById[sid]
if (l != null) {
for (var key in l) {
var listener = l[key]
if (--listener.missing === 0) {
this.whenOperationsExist([], listener.op)
}
}
}
var t = this.initializedTypes[JSON.stringify(op.parent)]
// Delete if DS says this is actually deleted
var opIsDeleted = yield* transaction.isDeleted(op.id)
if (!op.deleted && opIsDeleted) {
var delop = {
struct: 'Delete',
target: op.id
}
yield* Y.Struct['Delete'].execute.call(transaction, delop)
}
// notify parent, if it was instanciated as a custom type
if (t != null) {
yield* t._changed(transaction, Y.utils.copyObject(op))
}
}
}
whenTransactionsFinished () {
if (this.transactionInProgress) {
if (this.transactionsFinished == null) {
var resolve
var promise = new Promise(function (r) {
resolve = r
})
this.transactionsFinished = {
resolve: resolve,
promise: promise
}
return promise
} else {
return this.transactionsFinished.promise
}
} else {
return Promise.resolve()
}
}
// Check if there is another transaction request.
// * the last transaction is always a flush :)
getNextRequest () {
if (this.waitingTransactions.length === 0) {
if (this.transactionIsFlushed) {
this.transactionInProgress = false
this.transactionIsFlushed = false
if (this.transactionsFinished != null) {
this.transactionsFinished.resolve()
this.transactionsFinished = null
}
return null
} else {
this.transactionIsFlushed = true
return function * () {
yield* this.flush()
}
}
} else {
this.transactionIsFlushed = false
return this.waitingTransactions.shift()
}
}
requestTransaction (makeGen/* :any */, callImmediately) {
this.waitingTransactions.push(makeGen)
if (!this.transactionInProgress) {
this.transactionInProgress = true
if (false || callImmediately) { // TODO: decide whether this is ok or not..
this.transact(this.getNextRequest())
} else {
var self = this
setTimeout(function () {
self.transact(self.getNextRequest())
}, 0)
}
}
}
}
Y.AbstractDatabase = AbstractDatabase
}
},{}],4:[function(require,module,exports){
/* @flow */
'use strict'
/*
An operation also defines the structure of a type. This is why operation and
structure are used interchangeably here.
It must be of the type Object. I hope to achieve some performance
improvements when working on databases that support the json format.
An operation must have the following properties:
* encode
- Encode the structure in a readable format (preferably string- todo)
* decode (todo)
- decode structure to json
* execute
- Execute the semantics of an operation.
* requiredOps
- Operations that are required to execute this operation.
*/
module.exports = function (Y/* :any */) {
var Struct = {
/* This is the only operation that is actually not a structure, because
it is not stored in the OS. This is why it _does not_ have an id
op = {
target: Id
}
*/
Delete: {
encode: function (op) {
return op
},
requiredOps: function (op) {
return [] // [op.target]
},
execute: function * (op) {
return yield* this.deleteOperation(op.target)
}
},
Insert: {
/* {
content: any,
id: Id,
left: Id,
origin: Id,
right: Id,
parent: Id,
parentSub: string (optional), // child of Map type
}
*/
encode: function (op/* :Insertion */) /* :Insertion */ {
// TODO: you could not send the "left" property, then you also have to
// "op.left = null" in $execute or $decode
var e/* :any */ = {
id: op.id,
left: op.left,
right: op.right,
origin: op.origin,
parent: op.parent,
struct: op.struct
}
if (op.parentSub != null) {
e.parentSub = op.parentSub
}
if (op.opContent != null) {
e.opContent = op.opContent
} else {
e.content = op.content
}
return e
},
requiredOps: function (op) {
var ids = []
if (op.left != null) {
ids.push(op.left)
}
if (op.right != null) {
ids.push(op.right)
}
if (op.origin != null && !Y.utils.compareIds(op.left, op.origin)) {
ids.push(op.origin)
}
// if (op.right == null && op.left == null) {
ids.push(op.parent)
if (op.opContent != null) {
ids.push(op.opContent)
}
return ids
},
getDistanceToOrigin: function * (op) {
if (op.left == null) {
return 0
} else {
var d = 0
var o = yield* this.getOperation(op.left)
while (!Y.utils.compareIds(op.origin, (o ? o.id : null))) {
d++
if (o.left == null) {
break
} else {
o = yield* this.getOperation(o.left)
}
}
return d
}
},
/*
# $this has to find a unique position between origin and the next known character
# case 1: $origin equals $o.origin: the $creator parameter decides if left or right
# let $OL= [o1,o2,o3,o4], whereby $this is to be inserted between o1 and o4
# o2,o3 and o4 origin is 1 (the position of o2)
# there is the case that $this.creator < o2.creator, but o3.creator < $this.creator
# then o2 knows o3. Since on another client $OL could be [o1,o3,o4] the problem is complex
# therefore $this would be always to the right of o3
# case 2: $origin < $o.origin
# if current $this insert_position > $o origin: $this ins
# else $insert_position will not change
# (maybe we encounter case 1 later, then this will be to the right of $o)
# case 3: $origin > $o.origin
# $this insert_position is to the left of $o (forever!)
*/
execute: function *(op) {
var i // loop counter
var distanceToOrigin = i = yield* Struct.Insert.getDistanceToOrigin.call(this, op) // most cases: 0 (starts from 0)
if (op.origin != null) { // TODO: !== instead of !=
// we save in origin that op originates in it
// we need that later when we eventually garbage collect origin (see transaction)
var origin = yield* this.getOperation(op.origin)
if (origin.originOf == null) {
origin.originOf = []
}
origin.originOf.push(op.id)
yield* this.setOperation(origin)
}
// now we begin to insert op in the list of insertions..
var o
var parent
var start
// find o. o is the first conflicting operation
if (op.left != null) {
o = yield* this.getOperation(op.left)
o = (o.right == null) ? null : yield* this.getOperation(o.right)
} else { // left == null
parent = yield* this.getOperation(op.parent)
let startId = op.parentSub ? parent.map[op.parentSub] : parent.start
start = startId == null ? null : yield* this.getOperation(startId)
o = start
}
// handle conflicts
while (true) {
if (o != null && !Y.utils.compareIds(o.id, op.right)) {
var oOriginDistance = yield* Struct.Insert.getDistanceToOrigin.call(this, o)
if (oOriginDistance === i) {
// case 1
if (o.id[0] < op.id[0]) {
op.left = o.id
distanceToOrigin = i + 1
}
} else if (oOriginDistance < i) {
// case 2
if (i - distanceToOrigin <= oOriginDistance) {
op.left = o.id
distanceToOrigin = i + 1
}
} else {
break
}
i++
if (o.right != null) {
o = yield* this.getOperation(o.right)
} else {
o = null
}
} else {
break
}
}
// reconnect..
var left = null
var right = null
if (parent == null) {
parent = yield* this.getOperation(op.parent)
}
// reconnect left and set right of op
if (op.left != null) {
left = yield* this.getOperation(op.left)
op.right = left.right
left.right = op.id
yield* this.setOperation(left)
} else {
op.right = op.parentSub ? parent.map[op.parentSub] || null : parent.start
}
// reconnect right
if (op.right != null) {
right = yield* this.getOperation(op.right)
right.left = op.id
// if right exists, and it is supposed to be gc'd. Remove it from the gc
if (right.gc != null) {
this.store.removeFromGarbageCollector(right)
}
yield* this.setOperation(right)
}
// update parents .map/start/end properties
if (op.parentSub != null) {
if (left == null) {
parent.map[op.parentSub] = op.id
yield* this.setOperation(parent)
}
// is a child of a map struct.
// Then also make sure that only the most left element is not deleted
if (op.right != null) {
yield* this.deleteOperation(op.right, true)
}
if (op.left != null) {
yield* this.deleteOperation(op.id, true)
}
} else {
if (right == null || left == null) {
if (right == null) {
parent.end = op.id
}
if (left == null) {
parent.start = op.id
}
yield* this.setOperation(parent)
}
}
}
},
List: {
/*
{
start: null,
end: null,
struct: "List",
type: "",
id: this.os.getNextOpId()
}
*/
create: function (id) {
return {
start: null,
end: null,
struct: 'List',
id: id
}
},
encode: function (op) {
return {
struct: 'List',
id: op.id,
type: op.type
}
},
requiredOps: function () {
/*
var ids = []
if (op.start != null) {
ids.push(op.start)
}
if (op.end != null){
ids.push(op.end)
}
return ids
*/
return []
},
execute: function * (op) {
op.start = null
op.end = null
},
ref: function * (op, pos) {
if (op.start == null) {
return null
}
var res = null
var o = yield* this.getOperation(op.start)
while (true) {
if (!o.deleted) {
res = o
pos--
}
if (pos >= 0 && o.right != null) {
o = yield* this.getOperation(o.right)
} else {
break
}
}
return res
},
map: function * (o, f) {
o = o.start
var res = []
while (o != null) { // TODO: change to != (at least some convention)
var operation = yield* this.getOperation(o)
if (!operation.deleted) {
res.push(f(operation))
}
o = operation.right
}
return res
}
},
Map: {
/*
{
map: {},
struct: "Map",
type: "",
id: this.os.getNextOpId()
}
*/
create: function (id) {
return {
id: id,
map: {},
struct: 'Map'
}
},
encode: function (op) {
return {
struct: 'Map',
type: op.type,
id: op.id,
map: {} // overwrite map!!
}
},
requiredOps: function () {
return []
},
execute: function * () {},
/*
Get a property by name
*/
get: function * (op, name) {
var oid = op.map[name]
if (oid != null) {
var res = yield* this.getOperation(oid)
if (res == null || res.deleted) {
return void 0
} else if (res.opContent == null) {
return res.content
} else {
return yield* this.getType(res.opContent)
}
}
}
}
}
Y.Struct = Struct
}
},{}],5:[function(require,module,exports){
/* @flow */
'use strict'
/*
Partial definition of a transaction
A transaction provides all the the async functionality on a database.
By convention, a transaction has the following properties:
* ss for StateSet
* os for OperationStore
* ds for DeleteStore
A transaction must also define the following methods:
* checkDeleteStoreForState(state)
- When increasing the state of a user, an operation with an higher id
may already be garbage collected, and therefore it will never be received.
update the state to reflect this knowledge. This won't call a method to save the state!
* getDeleteSet(id)
- Get the delete set in a readable format:
{
"userX": [
[5,1], // starting from position 5, one operations is deleted
[9,4] // starting from position 9, four operations are deleted
],
"userY": ...
}
* getOpsFromDeleteSet(ds) -- TODO: just call this.deleteOperation(id) here
- get a set of deletions that need to be applied in order to get to
achieve the state of the supplied ds
* setOperation(op)
- write `op` to the database.
Note: this is allowed to return an in-memory object.
E.g. the Memory adapter returns the object that it has in-memory.
Changing values on this object will be stored directly in the database
without calling this function. Therefore,
setOperation may have no functionality in some adapters. This also has
implications on the way we use operations that were served from the database.
We try not to call copyObject, if not necessary.
* addOperation(op)
- add an operation to the database.
This may only be called once for every op.id
Must return a function that returns the next operation in the database (ordered by id)
* getOperation(id)
* removeOperation(id)
- remove an operation from the database. This is called when an operation
is garbage collected.
* setState(state)
- `state` is of the form
{
user: "1",
clock: 4
} <- meaning that we have four operations from user "1"
(with these id's respectively: 0, 1, 2, and 3)
* getState(user)
* getStateVector()
- Get the state of the OS in the form
[{
user: "userX",
clock: 11
},
..
]
* getStateSet()
- Get the state of the OS in the form
{
"userX": 11,
"userY": 22
}
* getOperations(startSS)
- Get the all the operations that are necessary in order to achive the
stateSet of this user, starting from a stateSet supplied by another user
* makeOperationReady(ss, op)
- this is called only by `getOperations(startSS)`. It makes an operation
applyable on a given SS.
*/
module.exports = function (Y/* :any */) {
class TransactionInterface {
/* ::
store: Y.AbstractDatabase;
ds: Store;
os: Store;
ss: Store;
*/
/*
Get a type based on the id of its model.
If it does not exist yes, create it.
TODO: delete type from store.initializedTypes[id] when corresponding id was deleted!
*/
* getType (id) {
var sid = JSON.stringify(id)
var t = this.store.initializedTypes[sid]
if (t == null) {
var op/* :MapStruct | ListStruct */ = yield* this.getOperation(id)
if (op != null) {
t = yield* Y[op.type].initType.call(this, this.store, op)
this.store.initializedTypes[sid] = t
}
}
return t
}
* createType (typedefinition) {
var structname = typedefinition.struct
var id = this.store.getNextOpId()
var op = Y.Struct[structname].create(id)
op.type = typedefinition.name
yield* this.applyCreatedOperations([op])
return yield* this.getType(id)
}
/*
Apply operations that this user created (no remote ones!)
* does not check for Struct.*.requiredOps()
* also broadcasts it through the connector
*/
* applyCreatedOperations (ops) {
var send = []
for (var i = 0; i < ops.length; i++) {
var op = ops[i]
yield* this.store.tryExecute.call(this, op)
if (op.id == null || op.id[0] !== '_') {
send.push(Y.Struct[op.struct].encode(op))
}
}
if (!this.store.y.connector.isDisconnected() && send.length > 0) { // TODO: && !this.store.forwardAppliedOperations (but then i don't send delete ops)
// is connected, and this is not going to be send in addOperation
this.store.y.connector.broadcastOps(send)
}
}
* deleteList (start) {
if (this.store.y.connector.isSynced) {
while (start != null && this.store.y.connector.isSynced) {
start = yield* this.getOperation(start)
start.gc = true
yield* this.setOperation(start)
// TODO: will always reset the parent..
this.store.gc1.push(start.id)
start = start.right
}
} else {
// TODO: when not possible??? do later in (gcWhenSynced)
}
}
/*
Mark an operation as deleted, and add it to the GC, if possible.
*/
* deleteOperation (targetId, preventCallType) /* :Generator<any, any, any> */ {
var target = yield* this.getOperation(targetId)
var callType = false
if (target == null || !target.deleted) {
yield* this.markDeleted(targetId, 1)
}
if (target != null && target.gc == null) {
if (!target.deleted) {
callType = true
// set deleted & notify type
target.deleted = true
/*
if (!preventCallType) {
var type = this.store.initializedTypes[JSON.stringify(target.parent)]
if (type != null) {
yield* type._changed(this, {
struct: 'Delete',
target: targetId
})
}
}
*/
// delete containing lists
if (target.start != null) {
// TODO: don't do it like this .. -.-
yield* this.deleteList(target.start)
yield* this.deleteList(target.id)
}
if (target.map != null) {
for (var name in target.map) {
yield* this.deleteList(target.map[name])
}
// TODO: here to.. (see above)
yield* this.deleteList(target.id)
}
if (target.opContent != null) {
yield* this.deleteOperation(target.opContent)
target.opContent = null
}
}
var left
if (target.left != null) {
left = yield* this.getOperation(target.left)
} else {
left = null
}
this.store.addToGarbageCollector(target, left)
// set here because it was deleted and/or gc'd
yield* this.setOperation(target)
/*
Check if it is possible to add right to the gc.
Because this delete can't be responsible for left being gc'd,
we don't have to add left to the gc..
*/
var right
if (target.right != null) {
right = yield* this.getOperation(target.right)
} else {
right = null
}
if (
right != null &&
this.store.addToGarbageCollector(right, target)
) {
yield* this.setOperation(right)
}
return callType
}
}
/*
Mark an operation as deleted&gc'd
*/
* markGarbageCollected (id, len) {
// this.mem.push(["gc", id]);
var n = yield* this.markDeleted(id, len)
if (n.id[1] < id[1] && !n.gc) {
// un-extend left
var newlen = n.len - (id[1] - n.id[1])
n.len -= newlen
yield* this.ds.put(n)
n = {id: id, len: newlen, gc: false}
yield* this.ds.put(n)
}
// get prev&next before adding a new operation
var prev = yield* this.ds.findPrev(id)
var next = yield* this.ds.findNext(id)
if (id[1] < n.id[1] + n.len - len && !n.gc) {
// un-extend right
yield* this.ds.put({id: [id[0], id[1] + 1], len: n.len - 1, gc: false})
n.len = 1
}
// set gc'd
n.gc = true
// can extend left?
if (
prev != null &&
prev.gc &&
Y.utils.compareIds([prev.id[0], prev.id[1] + prev.len], n.id)
) {
prev.len += n.len
yield* this.ds.delete(n.id)
n = prev
// ds.put n here?
}
// can extend right?
if (
next != null &&
next.gc &&
Y.utils.compareIds([n.id[0], n.id[1] + n.len], next.id)
) {
n.len += next.len
yield* this.ds.delete(next.id)
}
yield* this.ds.put(n)
}
/*
Mark an operation as deleted.
returns the delete node
*/
* markDeleted (id, length) {
if (length == null) {
length = 1
}
// this.mem.push(["del", id]);
var n = yield* this.ds.findWithUpperBound(id)
if (n != null && n.id[0] === id[0]) {
if (n.id[1] <= id[1] && id[1] <= n.id[1] + n.len) {
// id is in n's range
var diff = id[1] + length - (n.id[1] + n.len) // overlapping right
if (diff > 0) {
// id+length overlaps n
if (!n.gc) {
n.len += diff
} else {
diff = n.id[1] + n.len - id[1] // overlapping left (id till n.end)
if (diff < length) {
// a partial deletion
n = {id: [id[0], id[1] + diff], len: length - diff, gc: false}
yield* this.ds.put(n)
} else {
// already gc'd
throw new Error('Cannot happen! (it dit though.. :()')
// return n
}
}
} else {
// no overlapping, already deleted
return n
}
} else {
// cannot extend left (there is no left!)
n = {id: id, len: length, gc: false}
yield* this.ds.put(n) // TODO: you double-put !!
}
} else {
// cannot extend left
n = {id: id, len: length, gc: false}
yield* this.ds.put(n)
}
// can extend right?
var next = yield* this.ds.findNext(n.id)
if (
next != null &&
n.id[0] === next.id[0] &&
n.id[1] + n.len >= next.id[1]
) {
diff = n.id[1] + n.len - next.id[1] // from next.start to n.end
if (next.gc) {
if (diff >= 0) {
n.len -= diff
if (diff > next.len) {
// need to create another deletion after $next
// TODO: (may not be necessary, because this case shouldn't happen!)
// also this is supposed to return a deletion range. which one to choose? n or the new created deletion?
throw new Error('This case is not handled (on purpose!)')
}
} // else: everything is fine :)
} else {
if (diff >= 0) {
if (diff > next.len) {
// may be neccessary to extend next.next!
// TODO: (may not be necessary, because this case shouldn't happen!)
throw new Error('This case is not handled (on purpose!)')
}
n.len += next.len - diff
yield* this.ds.delete(next.id)
}
}
}
yield* this.ds.put(n)
return n
}
/*
Call this method when the client is connected&synced with the
other clients (e.g. master). This will query the database for
operations that can be gc'd and add them to the garbage collector.
*/
* garbageCollectAfterSync () {
yield* this.os.iterate(this, null, null, function * (op) {
if (op.deleted && op.left != null) {
var left = yield* this.getOperation(op.left)
this.store.addToGarbageCollector(op, left)
}
})
}
/*
Really remove an op and all its effects.
The complicated case here is the Insert operation:
* reset left
* reset right
* reset parent.start
* reset parent.end
* reset origins of all right ops
*/
* garbageCollectOperation (id) {
this.store.addToDebug('yield* this.garbageCollectOperation(', id, ')')
var o = yield* this.getOperation(id)
yield* this.markGarbageCollected(id, 1) // always mark gc'd
// if op exists, then clean that mess up..
if (o != null) {
/*
if (!o.deleted) {
yield* this.deleteOperation(id)
o = yield* this.getOperation(id)
}
*/
// remove gc'd op from the left op, if it exists
if (o.left != null) {
var left = yield* this.getOperation(o.left)
left.right = o.right
yield* this.setOperation(left)
}
// remove gc'd op from the right op, if it exists
// also reset origins of right ops
if (o.right != null) {
var right = yield* this.getOperation(o.right)
right.left = o.left
if (o.originOf != null && o.originOf.length > 0) {
// find new origin of right ops
// origin is the first left deleted operation
var neworigin = o.left
var neworigin_ = null
while (neworigin != null) {
neworigin_ = yield* this.getOperation(neworigin)
if (neworigin_.deleted) {
break
}
neworigin = neworigin_.left
}
// reset origin of all right ops (except first right - duh!),
/* ** The following code does not rely on the the originOf property **
I recently added originOf to all Insert Operations (see Struct.Insert.execute),
which saves which operations originate in a Insert operation.
Garbage collecting without originOf is more memory efficient, but is nearly impossible for large texts, or lists!
But I keep this code for now
```
// reset origin of right
right.origin = neworigin
// search until you find origin pointer to the left of o
if (right.right != null) {
var i = yield* this.getOperation(right.right)
var ids = [o.id, o.right]
while (ids.some(function (id) {
return Y.utils.compareIds(id, i.origin)
})) {
if (Y.utils.compareIds(i.origin, o.id)) {
// reset origin of i
i.origin = neworigin
yield* this.setOperation(i)
}
// get next i
if (i.right == null) {
break
} else {
ids.push(i.id)
i = yield* this.getOperation(i.right)
}
}
}
```
*/
// ** Now the new implementation starts **
// reset neworigin of all originOf[*]
for (var _i in o.originOf) {
var originsIn = yield* this.getOperation(o.originOf[_i])
if (originsIn != null) {
originsIn.origin = neworigin
yield* this.setOperation(originsIn)
}
}
if (neworigin != null) {
if (neworigin_.originOf == null) {
neworigin_.originOf = o.originOf
} else {
neworigin_.originOf = o.originOf.concat(neworigin_.originOf)
}
yield* this.setOperation(neworigin_)
}
// we don't need to set right here, because
// right should be in o.originOf => it is set it the previous for loop
} else {
// we didn't need to reset the origin of right
// so we have to set right here
yield* this.setOperation(right)
}
// o may originate in another operation.
// Since o is deleted, we have to reset o.origin's `originOf` property
if (o.origin != null) {
var origin = yield* this.getOperation(o.origin)
origin.originOf = origin.originOf.filter(function (_id) {
return !Y.utils.compareIds(id, _id)
})
yield* this.setOperation(origin)
}
}
if (o.parent != null) {
// remove gc'd op from parent, if it exists
var parent /* MapOperation */ = yield* this.getOperation(o.parent)
var setParent = false // whether to save parent to the os
if (o.parentSub != null) {
if (Y.utils.compareIds(parent.map[o.parentSub], o.id)) {
setParent = true
parent.map[o.parentSub] = o.right
}
} else {
if (Y.utils.compareIds(parent.start, o.id)) {
// gc'd op is the start
setParent = true
parent.start = o.right
}
if (Y.utils.compareIds(parent.end, o.id)) {
// gc'd op is the end
setParent = true
parent.end = o.left
}
}
if (setParent) {
yield* this.setOperation(parent)
}
}
// finally remove it from the os
yield* this.removeOperation(o.id)
}
}
* checkDeleteStoreForState (state) {
var n = yield* this.ds.findWithUpperBound([state.user, state.clock])
if (n != null && n.id[0] === state.user && n.gc) {
state.clock = Math.max(state.clock, n.id[1] + n.len)
}
}
/*
apply a delete set in order to get
the state of the supplied ds
*/
* applyDeleteSet (ds) {
var deletions = []
function createDeletions (user, start, len, gc) {
deletions.push([user, start, len, gc])
}
for (var user in ds) {
var dv = ds[user]
var pos = 0
var d = dv[pos]
yield* this.ds.iterate(this, [user, 0], [user, Number.MAX_VALUE], function * (n) {
// cases:
// 1. d deletes something to the right of n
// => go to next n (break)
// 2. d deletes something to the left of n
// => create deletions
// => reset d accordingly
// *)=> if d doesn't delete anything anymore, go to next d (continue)
// 3. not 2) and d deletes something that also n deletes
// => reset d so that it doesn't contain n's deletion
// *)=> if d does not delete anything anymore, go to next d (continue)
while (d != null) {
var diff = 0 // describe the diff of length in 1) and 2)
if (n.id[1] + n.len <= d[0]) {
// 1)
break
} else if (d[0] < n.id[1]) {
// 2)
// delete maximum the len of d
// else delete as much as possible
diff = Math.min(n.id[1] - d[0], d[1])
createDeletions(user, d[0], diff, d[2])
} else {
// 3)
diff = n.id[1] + n.len - d[0] // never null (see 1)
if (d[2] && !n.gc) {
// d marks as gc'd but n does not
// then delete either way
createDeletions(user, d[0], Math.min(diff, d[1]), d[2])
}
}
if (d[1] <= diff) {
// d doesn't delete anything anymore
d = dv[++pos]
} else {
d[0] = d[0] + diff // reset pos
d[1] = d[1] - diff // reset length
}
}
})
// for the rest.. just apply it
for (; pos < dv.length; pos++) {
d = dv[pos]
createDeletions(user, d[0], d[1], d[2])
}
}
for (var i = 0; i < deletions.length; i++) {
var del = deletions[i]
// always try to delete..
var state = yield* this.getState(del[0])
if (del[1] < state.clock) {
for (let c = del[1]; c < del[1] + del[2]; c++) {
var id = [del[0], c]
var addOperation = yield* this.deleteOperation(id)
if (addOperation) {
// TODO:.. really .. here? You could prevent calling all these functions in operationAdded
yield* this.store.operationAdded(this, {struct: 'Delete', target: id})
}
if (del[3]) {
// gc
yield* this.garbageCollectOperation(id)
}
}
} else {
if (del[3]) {
yield* this.markGarbageCollected([del[0], del[1]], del[2])
} else {
yield* this.markDeleted([del[0], del[1]], del[2])
}
}
if (del[3]) {
// check to increase the state of the respective user
if (state.clock >= del[1] && state.clock < del[1] + del[2]) {
state.clock = del[1] + del[2]
// also check if more expected operations were gc'd
yield* this.checkDeleteStoreForState(state) // TODO: unneccessary?
// then set the state
yield* this.setState(state)
}
}
if (this.store.forwardAppliedOperations) {
var ops = []
for (let c = del[1]; c < del[1] + del[2]; c++) {
ops.push({struct: 'Delete', target: [d[0], c]}) // TODO: implement Delete with deletion length!
}
this.store.y.connector.broadcastOps(ops)
}
}
}
* isGarbageCollected (id) {
var n = yield* this.ds.findWithUpperBound(id)
return n != null && n.id[0] === id[0] && id[1] < n.id[1] + n.len && n.gc
}
/*
A DeleteSet (ds) describes all the deleted ops in the OS
*/
* getDeleteSet () {
var ds = {}
yield* this.ds.iterate(this, null, null, function * (n) {
var user = n.id[0]
var counter = n.id[1]
var len = n.len
var gc = n.gc
var dv = ds[user]
if (dv === void 0) {
dv = []
ds[user] = dv
}
dv.push([counter, len, gc])
})
return ds
}
* isDeleted (id) {
var n = yield* this.ds.findWithUpperBound(id)
return n != null && n.id[0] === id[0] && id[1] < n.id[1] + n.len
}
* setOperation (op) {
yield* this.os.put(op)
return op
}
* addOperation (op) {
yield* this.os.put(op)
if (!this.store.y.connector.isDisconnected() && this.store.forwardAppliedOperations && op.id[0] !== '_') {
// is connected, and this is not going to be send in addOperation
this.store.y.connector.broadcastOps([op])
}
}
* getOperation (id/* :any */)/* :Transaction<any> */ {
var o = yield* this.os.find(id)
if (o != null || id[0] !== '_') {
return o
} else {
// need to generate this operation
if (this.store._nextUserId == null) {
var struct = id[1].split('_')[0]
// this.store._nextUserId = id
var op = Y.Struct[struct].create(id)
yield* this.setOperation(op)
// delete this.store._nextUserId
return op
} else {
// Can only generate one operation at a time
return null
}
}
}
* removeOperation (id) {
yield* this.os.delete(id)
}
* setState (state) {
var val = {
id: [state.user],
clock: state.clock
}
yield* this.ss.put(val)
}
* getState (user) {
var n = yield* this.ss.find([user])
var clock = n == null ? null : n.clock
if (clock == null) {
clock = 0
}
return {
user: user,
clock: clock
}
}
* getStateVector () {
var stateVector = []
yield* this.ss.iterate(this, null, null, function * (n) {
stateVector.push({
user: n.id[0],
clock: n.clock
})
})
return stateVector
}
* getStateSet () {
var ss = {}
yield* this.ss.iterate(this, null, null, function * (n) {
ss[n.id[0]] = n.clock
})
return ss
}
/*
Here, we make all missing operations executable for the receiving user.
Notes:
startSS: denotes to the SV that the remote user sent
currSS: denotes to the state vector that the user should have if he
applies all already sent operations (increases is each step)
We face several problems:
* Execute op as is won't work because ops depend on each other
-> find a way so that they do not anymore
* When changing left, must not go more to the left than the origin
* When changing right, you have to consider that other ops may have op
as their origin, this means that you must not set one of these ops
as the new right (interdependencies of ops)
* can't just go to the right until you find the first known operation,
With currSS
-> interdependency of ops is a problem
With startSS
-> leads to inconsistencies when two users join at the same time.
Then the position depends on the order of execution -> error!
Solution:
-> re-create originial situation
-> set op.left = op.origin (which never changes)
-> set op.right
to the first operation that is known (according to startSS)
or to the first operation that has an origin that is not to the
right of op.
-> Enforces unique execution order -> happy user
Improvements: TODO
* Could set left to origin, or the first known operation
(startSS or currSS.. ?)
-> Could be necessary when I turn GC again.
-> Is a bad(ish) idea because it requires more computation
What we do:
* Iterate over all missing operations.
* When there is an operation, where the right op is known, send this op all missing ops to the left to the user
* I explained above what we have to do with each operation. Here is how we do it efficiently:
1. Go to the left until you find either op.origin, or a known operation (let o denote current operation in the iteration)
2. Found a known operation -> set op.left = o, and send it to the user. stop
3. Found o = op.origin -> set op.left = op.origin, and send it to the user. start again from 1. (set op = o)
4. Found some o -> set o.right = op, o.left = o.origin, send it to the user, continue
*/
* getOperations (startSS) {
// TODO: use bounds here!
if (startSS == null) {
startSS = {}
}
var send = []
var endSV = yield* this.getStateVector()
for (var endState of endSV) {
var user = endState.user
if (user === '_') {
continue
}
var startPos = startSS[user] || 0
yield* this.os.iterate(this, [user, startPos], [user, Number.MAX_VALUE], function * (op) {
op = Y.Struct[op.struct].encode(op)
if (op.struct !== 'Insert') {
send.push(op)
} else if (op.right == null || op.right[1] < (startSS[op.right[0]] || 0)) {
// case 1. op.right is known
var o = op
// Remember: ?
// -> set op.right
// 1. to the first operation that is known (according to startSS)
// 2. or to the first operation that has an origin that is not to the
// right of op.
// For this we maintain a list of ops which origins are not found yet.
var missing_origins = [op]
var newright = op.right
while (true) {
if (o.left == null) {
op.left = null
send.push(op)
if (!Y.utils.compareIds(o.id, op.id)) {
o = Y.Struct[op.struct].encode(o)
o.right = missing_origins[missing_origins.length - 1].id
send.push(o)
}
break
}
o = yield* this.getOperation(o.left)
// we set another o, check if we can reduce $missing_origins
while (missing_origins.length > 0 && Y.utils.compareIds(missing_origins[missing_origins.length - 1].origin, o.id)) {
missing_origins.pop()
}
if (o.id[1] < (startSS[o.id[0]] || 0)) {
// case 2. o is known
op.left = o.id
send.push(op)
break
} else if (Y.utils.compareIds(o.id, op.origin)) {
// case 3. o is op.origin
op.left = op.origin
send.push(op)
op = Y.Struct[op.struct].encode(o)
op.right = newright
if (missing_origins.length > 0) {
console.log('This should not happen .. :( please report this')
}
missing_origins = [op]
} else {
// case 4. send o, continue to find op.origin
var s = Y.Struct[op.struct].encode(o)
s.right = missing_origins[missing_origins.length - 1].id
s.left = s.origin
send.push(s)
missing_origins.push(o)
}
}
}
})
}
return send.reverse()
}
/* this is what we used before.. use this as a reference..
* makeOperationReady (startSS, op) {
op = Y.Struct[op.struct].encode(op)
op = Y.utils.copyObject(op)
var o = op
var ids = [op.id]
// search for the new op.right
// it is either the first known op (according to startSS)
// or the o that has no origin to the right of op
// (this is why we use the ids array)
while (o.right != null) {
var right = yield* this.getOperation(o.right)
if (o.right[1] < (startSS[o.right[0]] || 0) || !ids.some(function (id) {
return Y.utils.compareIds(id, right.origin)
})) {
break
}
ids.push(o.right)
o = right
}
op.right = o.right
op.left = op.origin
return op
}
*/
* flush () {
yield* this.os.flush()
yield* this.ss.flush()
yield* this.ds.flush()
}
}
Y.Transaction = TransactionInterface
}
},{}],6:[function(require,module,exports){
/* @flow */
'use strict'
/*
EventHandler is an helper class for constructing custom types.
Why: When constructing custom types, you sometimes want your types to work
synchronous: E.g.
``` Synchronous
mytype.setSomething("yay")
mytype.getSomething() === "yay"
```
versus
``` Asynchronous
mytype.setSomething("yay")
mytype.getSomething() === undefined
mytype.waitForSomething().then(function(){
mytype.getSomething() === "yay"
})
```
The structures usually work asynchronously (you have to wait for the
database request to finish). EventHandler helps you to make your type
synchronous.
*/
module.exports = function (Y /* : any*/) {
Y.utils = {}
class EventHandler {
/* ::
waiting: Array<Insertion | Deletion>;
awaiting: number;
onevent: Function;
eventListeners: Array<Function>;
*/
/*
onevent: is called when the structure changes.
Note: "awaiting opertations" is used to denote operations that were
prematurely called. Events for received operations can not be executed until
all prematurely called operations were executed ("waiting operations")
*/
constructor (onevent /* : Function */) {
this.waiting = []
this.awaiting = 0
this.onevent = onevent
this.eventListeners = []
}
destroy () {
this.waiting = null
this.awaiting = null
this.onevent = null
this.eventListeners = null
}
/*
Call this when a new operation arrives. It will be executed right away if
there are no waiting operations, that you prematurely executed
*/
receivedOp (op) {
if (this.awaiting <= 0) {
this.onevent([op])
} else {
this.waiting.push(Y.utils.copyObject(op))
}
}
/*
You created some operations, and you want the `onevent` function to be
called right away. Received operations will not be executed untill all
prematurely called operations are executed
*/
awaitAndPrematurelyCall (ops) {
this.awaiting++
this.onevent(ops)
}
/*
Basic event listener boilerplate...
TODO: maybe put this in a different type..
*/
addEventListener (f) {
this.eventListeners.push(f)
}
removeEventListener (f) {
this.eventListeners = this.eventListeners.filter(function (g) {
return f !== g
})
}
removeAllEventListeners () {
this.eventListeners = []
}
callEventListeners (event) {
for (var i = 0; i < this.eventListeners.length; i++) {
try {
this.eventListeners[i](event)
} catch (e) {
console.log('User events must not throw Errors!') // eslint-disable-line
}
}
}
/*
Call this when you successfully awaited the execution of n Insert operations
*/
awaitedInserts (n) {
var ops = this.waiting.splice(this.waiting.length - n)
for (var oid = 0; oid < ops.length; oid++) {
var op = ops[oid]
if (op.struct === 'Insert') {
for (var i = this.waiting.length - 1; i >= 0; i--) {
let w = this.waiting[i]
if (w.struct === 'Insert') {
if (Y.utils.compareIds(op.left, w.id)) {
// include the effect of op in w
w.right = op.id
// exclude the effect of w in op
op.left = w.left
} else if (Y.utils.compareIds(op.right, w.id)) {
// similar..
w.left = op.id
op.right = w.right
}
}
}
} else {
throw new Error('Expected Insert Operation!')
}
}
this._tryCallEvents()
}
/*
Call this when you successfully awaited the execution of n Delete operations
*/
awaitedDeletes (n, newLeft) {
var ops = this.waiting.splice(this.waiting.length - n)
for (var j = 0; j < ops.length; j++) {
var del = ops[j]
if (del.struct === 'Delete') {
if (newLeft != null) {
for (var i = 0; i < this.waiting.length; i++) {
let w = this.waiting[i]
// We will just care about w.left
if (w.struct === 'Insert' && Y.utils.compareIds(del.target, w.left)) {
w.left = newLeft
}
}
}
} else {
throw new Error('Expected Delete Operation!')
}
}
this._tryCallEvents()
}
/* (private)
Try to execute the events for the waiting operations
*/
_tryCallEvents () {
this.awaiting--
if (this.awaiting <= 0 && this.waiting.length > 0) {
var events = this.waiting
this.waiting = []
this.onevent(events)
}
}
}
Y.utils.EventHandler = EventHandler
/*
A wrapper for the definition of a custom type.
Every custom type must have three properties:
* struct
- Structname of this type
* initType
- Given a model, creates a custom type
* class
- the constructor of the custom type (e.g. in order to inherit from a type)
*/
class CustomType { // eslint-disable-line
/* ::
struct: any;
initType: any;
class: Function;
name: String;
*/
constructor (def) {
if (def.struct == null ||
def.initType == null ||
def.class == null ||
def.name == null
) {
throw new Error('Custom type was not initialized correctly!')
}
this.struct = def.struct
this.initType = def.initType
this.class = def.class
this.name = def.name
}
}
Y.utils.CustomType = CustomType
/*
Make a flat copy of an object
(just copy properties)
*/
function copyObject (o) {
var c = {}
for (var key in o) {
c[key] = o[key]
}
return c
}
Y.utils.copyObject = copyObject
/*
Defines a smaller relation on Id's
*/
function smaller (a, b) {
return a[0] < b[0] || (a[0] === b[0] && (a[1] < b[1] || typeof a[1] < typeof b[1]))
}
Y.utils.smaller = smaller
function compareIds (id1, id2) {
if (id1 == null || id2 == null) {
if (id1 == null && id2 == null) {
return true
}
return false
}
if (id1[0] === id2[0] && id1[1] === id2[1]) {
return true
} else {
return false
}
}
Y.utils.compareIds = compareIds
function createEmptyOpsArray (n) {
var a = new Array(n)
for (var i = 0; i < a.length; i++) {
a[i] = {
id: [null, null]
}
}
return a
}
function createSmallLookupBuffer (Store) {
/*
This buffer implements a very small buffer that temporarily stores operations
after they are read / before they are written.
The buffer basically implements FIFO. Often requested lookups will be re-queued every time they are looked up / written.
It can speed up lookups on Operation Stores and State Stores. But it does not require notable use of memory or processing power.
Good for os and ss, bot not for ds (because it often uses methods that require a flush)
I tried to optimize this for performance, therefore no highlevel operations.
*/
class SmallLookupBuffer extends Store {
constructor () {
super(...arguments)
this.writeBuffer = createEmptyOpsArray(5)
this.readBuffer = createEmptyOpsArray(10)
}
* find (id) {
var i, r
for (i = this.readBuffer.length - 1; i >= 0; i--) {
r = this.readBuffer[i]
// we don't have to use compareids, because id is always defined!
if (r.id[1] === id[1] && r.id[0] === id[0]) {
// found r
// move r to the end of readBuffer
for (; i < this.readBuffer.length - 1; i++) {
this.readBuffer[i] = this.readBuffer[i + 1]
}
this.readBuffer[this.readBuffer.length - 1] = r
return r
}
}
var o
for (i = this.writeBuffer.length - 1; i >= 0; i--) {
r = this.writeBuffer[i]
if (r.id[1] === id[1] && r.id[0] === id[0]) {
o = r
break
}
}
if (i < 0) {
// did not reach break in last loop
// read id and put it to the end of readBuffer
o = yield* super.find(id)
}
if (o != null) {
for (i = 0; i < this.readBuffer.length - 1; i++) {
this.readBuffer[i] = this.readBuffer[i + 1]
}
this.readBuffer[this.readBuffer.length - 1] = o
}
return o
}
* put (o) {
var id = o.id
var i, r // helper variables
for (i = this.writeBuffer.length - 1; i >= 0; i--) {
r = this.writeBuffer[i]
if (r.id[1] === id[1] && r.id[0] === id[0]) {
// is already in buffer
// forget r, and move o to the end of writeBuffer
for (; i < this.writeBuffer.length - 1; i++) {
this.writeBuffer[i] = this.writeBuffer[i + 1]
}
this.writeBuffer[this.writeBuffer.length - 1] = o
break
}
}
if (i < 0) {
// did not reach break in last loop
// write writeBuffer[0]
var write = this.writeBuffer[0]
if (write.id[0] !== null) {
yield* super.put(write)
}
// put o to the end of writeBuffer
for (i = 0; i < this.writeBuffer.length - 1; i++) {
this.writeBuffer[i] = this.writeBuffer[i + 1]
}
this.writeBuffer[this.writeBuffer.length - 1] = o
}
// check readBuffer for every occurence of o.id, overwrite if found
// whether found or not, we'll append o to the readbuffer
for (i = 0; i < this.readBuffer.length - 1; i++) {
r = this.readBuffer[i + 1]
if (r.id[1] === id[1] && r.id[0] === id[0]) {
this.readBuffer[i] = o
} else {
this.readBuffer[i] = r
}
}
this.readBuffer[this.readBuffer.length - 1] = o
}
* delete (id) {
var i, r
for (i = 0; i < this.readBuffer.length; i++) {
r = this.readBuffer[i]
if (r.id[1] === id[1] && r.id[0] === id[0]) {
this.readBuffer[i] = {
id: [null, null]
}
}
}
yield* this.flush()
yield* super.delete(id)
}
* findWithLowerBound () {
yield* this.flush()
return yield* super.findWithLowerBound.apply(this, arguments)
}
* findWithUpperBound () {
yield* this.flush()
return yield* super.findWithUpperBound.apply(this, arguments)
}
* findNext () {
yield* this.flush()
return yield* super.findNext.apply(this, arguments)
}
* findPrev () {
yield* this.flush()
return yield* super.findPrev.apply(this, arguments)
}
* iterate () {
yield* this.flush()
yield* super.iterate.apply(this, arguments)
}
* flush () {
for (var i = 0; i < this.writeBuffer.length; i++) {
var write = this.writeBuffer[i]
if (write.id[0] !== null) {
yield* super.put(write)
this.writeBuffer[i] = {
id: [null, null]
}
}
}
}
}
return SmallLookupBuffer
}
Y.utils.createSmallLookupBuffer = createSmallLookupBuffer
}
},{}],7:[function(require,module,exports){
/* @flow */
'use strict'
require('./Connector.js')(Y)
require('./Database.js')(Y)
require('./Transaction.js')(Y)
require('./Struct.js')(Y)
require('./Utils.js')(Y)
require('./Connectors/Test.js')(Y)
var requiringModules = {}
module.exports = Y
Y.requiringModules = requiringModules
Y.extend = function (name, value) {
Y[name] = value
if (requiringModules[name] != null) {
requiringModules[name].resolve()
delete requiringModules[name]
}
}
Y.requestModules = requestModules
function requestModules (modules) {
// determine if this module was compiled for es5 or es6 (y.js vs. y.es6)
// if Insert.execute is a Function, then it isnt a generator..
// then load the es5(.js) files..
var extention = typeof regeneratorRuntime !== 'undefined' ? '.js' : '.es6'
var promises = []
for (var i = 0; i < modules.length; i++) {
var modulename = 'y-' + modules[i].toLowerCase()
if (Y[modules[i]] == null) {
if (requiringModules[modules[i]] == null) {
// module does not exist
if (typeof window !== 'undefined' && window.Y !== 'undefined') {
var imported = document.createElement('script')
imported.src = Y.sourceDir + '/' + modulename + '/' + modulename + extention
document.head.appendChild(imported)
let requireModule = {}
requiringModules[modules[i]] = requireModule
requireModule.promise = new Promise(function (resolve) {
requireModule.resolve = resolve
})
promises.push(requireModule.promise)
} else {
require(modulename)(Y)
}
} else {
promises.push(requiringModules[modules[i]].promise)
}
}
}
return Promise.all(promises)
}
/* ::
type MemoryOptions = {
name: 'memory'
}
type IndexedDBOptions = {
name: 'indexeddb',
namespace: string
}
type DbOptions = MemoryOptions | IndexedDBOptions
type WebRTCOptions = {
name: 'webrtc',
room: string
}
type WebsocketsClientOptions = {
name: 'websockets-client',
room: string
}
type ConnectionOptions = WebRTCOptions | WebsocketsClientOptions
type YOptions = {
connector: ConnectionOptions,
db: DbOptions,
types: Array<TypeName>,
sourceDir: string,
share: {[key: string]: TypeName}
}
*/
function Y (opts/* :YOptions */) /* :Promise<YConfig> */ {
opts.types = opts.types != null ? opts.types : []
var modules = [opts.db.name, opts.connector.name].concat(opts.types)
for (var name in opts.share) {
modules.push(opts.share[name])
}
Y.sourceDir = opts.sourceDir
return Y.requestModules(modules).then(function () {
return new Promise(function (resolve) {
var yconfig = new YConfig(opts)
yconfig.db.whenUserIdSet(function () {
yconfig.init(function () {
resolve(yconfig)
})
})
})
})
}
class YConfig {
/* ::
db: Y.AbstractDatabase;
connector: Y.AbstractConnector;
share: {[key: string]: any};
options: Object;
*/
constructor (opts, callback) {
this.options = opts
this.db = new Y[opts.db.name](this, opts.db)
this.connector = new Y[opts.connector.name](this, opts.connector)
}
init (callback) {
var opts = this.options
var share = {}
this.share = share
this.db.requestTransaction(function * requestTransaction () {
// create shared object
for (var propertyname in opts.share) {
var typename = opts.share[propertyname]
var id = ['_', Y[typename].struct + '_' + propertyname]
var op = yield* this.getOperation(id)
if (op.type !== typename) {
// not already in the db
op.type = typename
yield* this.setOperation(op)
}
share[propertyname] = yield* this.getType(id)
}
this.store.whenTransactionsFinished()
.then(callback)
})
}
isConnected () {
return this.connector.isSynced
}
disconnect () {
return this.connector.disconnect()
}
reconnect () {
return this.connector.reconnect()
}
destroy () {
if (this.connector.destroy != null) {
this.connector.destroy()
} else {
this.connector.disconnect()
}
var self = this
this.db.requestTransaction(function * () {
yield* self.db.destroy()
self.connector = null
self.db = null
})
}
}
if (typeof window !== 'undefined') {
window.Y = Y
}
},{"./Connector.js":1,"./Connectors/Test.js":2,"./Database.js":3,"./Struct.js":4,"./Transaction.js":5,"./Utils.js":6}]},{},[7])