324 lines
9.4 KiB
JavaScript

'use strict'
const MongoClient = require('mongodb')
function withCallback(promise, cb) {
// Assume that cb is a function - type checks and handling type errors
// can be done by caller
if (cb) {
promise
.then(res => cb(null, res))
.catch(cb)
}
return promise
}
function defaultSerializeFunction(session) {
// Copy each property of the session to a new object
const obj = {}
let prop
for (prop in session) {
if (prop === 'cookie') {
// Convert the cookie instance to an object, if possible
// This gets rid of the duplicate object under session.cookie.data property
obj.cookie = session.cookie.toJSON ? session.cookie.toJSON() : session.cookie
} else {
obj[prop] = session[prop]
}
}
return obj
}
function computeTransformFunctions(options, defaultStringify) {
if (options.serialize || options.unserialize) {
return {
serialize: options.serialize || defaultSerializeFunction,
unserialize: options.unserialize || (x => x)
}
}
if (options.stringify === false || defaultStringify === false) {
return {
serialize: defaultSerializeFunction,
unserialize: x => x
}
}
if (options.stringify === true || defaultStringify === true) {
return {
serialize: JSON.stringify,
unserialize: JSON.parse
}
}
}
module.exports = function (connect) {
const Store = connect.Store || connect.session.Store
const MemoryStore = connect.MemoryStore || connect.session.MemoryStore
class MongoStore extends Store {
constructor(options) {
options = options || {}
/* Fallback */
if (options.fallbackMemory && MemoryStore) {
return new MemoryStore()
}
super(options)
/* Options */
this.ttl = options.ttl || 1209600 // 14 days
this.collectionName = options.collection || 'sessions'
this.autoRemove = options.autoRemove || 'native'
this.autoRemoveInterval = options.autoRemoveInterval || 10
this.transformFunctions = computeTransformFunctions(options, true)
this.options = options
this.changeState('init')
const newConnectionCallback = (err, db) => {
if (err) {
this.connectionFailed(err)
} else {
this.handleNewConnectionAsync(db)
}
}
if (options.url) {
// New native connection using url + mongoOptions
MongoClient.connect(options.url, options.mongoOptions || {}, newConnectionCallback)
} else if (options.mongooseConnection) {
// Re-use existing or upcoming mongoose connection
if (options.mongooseConnection.readyState === 1) {
this.handleNewConnectionAsync(options.mongooseConnection.db)
} else {
options.mongooseConnection.once('open', () => this.handleNewConnectionAsync(options.mongooseConnection.db))
}
} else if (options.db && options.db.listCollections) {
// Re-use existing or upcoming native connection
if (options.db.openCalled || options.db.openCalled === undefined) { // OpenCalled is undefined in mongodb@2.x
this.handleNewConnectionAsync(options.db)
} else {
options.db.open(newConnectionCallback)
}
} else if (options.dbPromise) {
options.dbPromise
.then(db => this.handleNewConnectionAsync(db))
.catch(err => this.connectionFailed(err))
} else {
throw new Error('Connection strategy not found')
}
this.changeState('connecting')
}
connectionFailed(err) {
this.changeState('disconnected')
throw err
}
handleNewConnectionAsync(db) {
this.db = db
return this
.setCollection(db.collection(this.collectionName))
.setAutoRemoveAsync()
.then(() => this.changeState('connected'))
}
setAutoRemoveAsync() {
const removeQuery = () => {
return {expires: {$lt: new Date()}}
}
switch (this.autoRemove) {
case 'native':
return this.collection.createIndex({expires: 1}, {expireAfterSeconds: 0})
case 'interval':
this.timer = setInterval(() => this.collection.remove(removeQuery(), {w: 0}), this.autoRemoveInterval * 1000 * 60)
this.timer.unref()
return Promise.resolve()
default:
return Promise.resolve()
}
}
changeState(newState) {
if (newState !== this.state) {
this.state = newState
this.emit(newState)
}
}
setCollection(collection) {
if (this.timer) {
clearInterval(this.timer)
}
this.collectionReadyPromise = undefined
this.collection = collection
return this
}
collectionReady() {
let promise = this.collectionReadyPromise
if (!promise) {
promise = new Promise((resolve, reject) => {
if (this.state === 'connected') {
return resolve(this.collection)
}
if (this.state === 'connecting') {
return this.once('connected', () => resolve(this.collection))
}
reject(new Error('Not connected'))
})
this.collectionReadyPromise = promise
}
return promise
}
computeStorageId(sessionId) {
if (this.options.transformId && typeof this.options.transformId === 'function') {
return this.options.transformId(sessionId)
}
return sessionId
}
/* Public API */
get(sid, callback) {
return withCallback(this.collectionReady()
.then(collection => collection.findOne({
_id: this.computeStorageId(sid),
$or: [
{expires: {$exists: false}},
{expires: {$gt: new Date()}}
]
}))
.then(session => {
if (session) {
const s = this.transformFunctions.unserialize(session.session)
if (this.options.touchAfter > 0 && session.lastModified) {
s.lastModified = session.lastModified
}
this.emit('get', sid)
return s
}
})
, callback)
}
set(sid, session, callback) {
// Removing the lastModified prop from the session object before update
if (this.options.touchAfter > 0 && session && session.lastModified) {
delete session.lastModified
}
let s
try {
s = {_id: this.computeStorageId(sid), session: this.transformFunctions.serialize(session)}
} catch (err) {
return callback(err)
}
if (session && session.cookie && session.cookie.expires) {
s.expires = new Date(session.cookie.expires)
} else {
// If there's no expiration date specified, it is
// browser-session cookie or there is no cookie at all,
// as per the connect docs.
//
// So we set the expiration to two-weeks from now
// - as is common practice in the industry (e.g Django) -
// or the default specified in the options.
s.expires = new Date(Date.now() + (this.ttl * 1000))
}
if (this.options.touchAfter > 0) {
s.lastModified = new Date()
}
return withCallback(this.collectionReady()
.then(collection => collection.updateOne({_id: this.computeStorageId(sid)}, {$set: s}, {upsert: true}))
.then(rawResponse => {
if (rawResponse.result) {
rawResponse = rawResponse.result
}
if (rawResponse && rawResponse.upserted) {
this.emit('create', sid)
} else {
this.emit('update', sid)
}
this.emit('set', sid)
})
, callback)
}
touch(sid, session, callback) {
const updateFields = {}
const touchAfter = this.options.touchAfter * 1000
const lastModified = session.lastModified ? session.lastModified.getTime() : 0
const currentDate = new Date()
// If the given options has a touchAfter property, check if the
// current timestamp - lastModified timestamp is bigger than
// the specified, if it's not, don't touch the session
if (touchAfter > 0 && lastModified > 0) {
const timeElapsed = currentDate.getTime() - session.lastModified
if (timeElapsed < touchAfter) {
return callback()
}
updateFields.lastModified = currentDate
}
if (session && session.cookie && session.cookie.expires) {
updateFields.expires = new Date(session.cookie.expires)
} else {
updateFields.expires = new Date(Date.now() + (this.ttl * 1000))
}
return withCallback(this.collectionReady()
.then(collection => collection.updateOne({_id: this.computeStorageId(sid)}, {$set: updateFields}))
.then(result => {
if (result.nModified === 0) {
throw new Error('Unable to find the session to touch')
} else {
this.emit('touch', sid, session)
}
})
, callback)
}
destroy(sid, callback) {
return withCallback(this.collectionReady()
.then(collection => collection.deleteOne({_id: this.computeStorageId(sid)}))
.then(() => this.emit('destroy', sid))
, callback)
}
length(callback) {
return withCallback(this.collectionReady()
.then(collection => collection.count({}))
, callback)
}
clear(callback) {
return withCallback(this.collectionReady()
.then(collection => collection.drop())
, callback)
}
close() {
if (this.db) {
this.db.close()
}
}
}
return MongoStore
}