import differenceInSeconds from 'date-fns/differenceInSeconds' ; import compareAsc from 'date-fns/compareAsc' ; import ReconnectingWebSocket from 'reconnecting-websocket' ; export interface MessageBase { id : string ; } export interface RequestMessage extends MessageBase { method : string ; params : { pageSize : number ; } & any ; notify ? : NotifyFn ; } export interface PayloadMessage < T extends unknown = unknown > extends MessageBase { error ? : unknown ; results ? : T [ ] ; } export interface SocketPoolItem < T extends unknown = unknown > { createdAt : Date ; notify : NotifyFn ; data : T [ ] ; done ? : boolean ; updatedAt ? : Date ; pickedAt ? : Date ; } export type OutMessageEvent = { id : string ; done : boolean ; error ? : unknown ; from : 'cache' | 'remote' ; } ; export type NotifyFn = ( event : OutMessageEvent ) => void ; const POOL_CACHE_EXPIRE_TIME = 30 ; const POOL_CACHE_MAX_CAPACITY = 10 ; export class ProviderProxy { private readonly _socket : ReconnectingWebSocket ; private readonly _pool : Map < string , SocketPoolItem > ; private readonly _globalNotify ? : NotifyFn ; constructor ( point , notifyFn ? ) { this . _socket = new ReconnectingWebSocket ( point ) ; this . _pool = new Map < string , SocketPoolItem > ( ) ; this . _globalNotify = notifyFn ; } waitingOpen = ( ) => { return new Promise < void > ( ( resolve , reject ) => { this . _socket . addEventListener ( 'open' , ( ) => resolve ( ) ) ; this . _socket . addEventListener ( 'error' , ( ) => reject ( ) ) ; } ) ; } ; onMessage = ( event ) => { const { id , results , error } = JSON . parse ( event . data ) as PayloadMessage ; const itemInPoll = this . _pool . get ( id ) ; if ( ! itemInPoll ) return ; if ( error || ! id ) { itemInPoll . notify ( { id , done : true , error : error , from : 'remote' } ) ; } const updatedAt = new Date ( ) ; if ( ! results || results . length === 0 ) { this . _pool . set ( id , { ... itemInPoll , done : true } ) ; itemInPoll . notify ( { id , done : true , from : 'remote' } ) ; return ; } const dataInPool = itemInPoll ?. data ?? [ ] ; const patchData = [ ... dataInPool , ... ( results ?? [ ] ) ] ; this . _pool . set ( id , { ... itemInPoll , updatedAt , data : patchData } ) ; itemInPoll . notify ( { id , done : false , from : 'remote' } ) ; } ; registerMessage = ( ) => { this . _socket . removeEventListener ( 'message' , this . onMessage ) ; this . _socket . addEventListener ( 'message' , this . onMessage ) ; } ; param message send ( message ) { this . clearPool ( ) ; const cache = this . _pool . get ( message . id ) ; if ( cache && ! cache . done ) return ; if ( cache && ! this . isExpired ( cache ) ) { const notify = message . notify || this . _globalNotify ! ; notify ( { id : message . id , done : true , from : 'cache' } ) ; return ; } this . _socket . send ( JSON . stringify ( { id : message . id , method : message . method , params : message . params } ) ) ; this . _pool . set ( message . id , { data : [ ] , createdAt : new Date ( ) , notify : message . notify || this . _globalNotify ! } ) ; } param message async sendAsync < T > ( message ) { this . clearPool ( ) ; const cache = this . _pool . get ( message . id ) ; if ( cache && ! this . isExpired ( cache ! ) ) return this . getResult < T > ( message . id ) ?? [ ] ; const innerMessagePromise = ( ) => new Promise < OutMessageEvent > ( ( resolve , reject ) => { ; ( message as RequestMessage ) . notify = ( info ) => { if ( info . done ) resolve ( info ) ; if ( info . error ) reject ( info ) ; } ; this . send ( message as RequestMessage ) ; } ) ; await innerMessagePromise ( ) ; return this . getResult < T > ( message . id ) ?? [ ] ; } get socket ( ) : ReconnectingWebSocket { return this . _socket ; } getResult < T > ( id ) { const item = this . _pool . get ( id ) ; if ( ! item ) return [ ] ; const newItem = { ... item , pickedAt : new Date ( ) } ; this . _pool . set ( id , newItem ) ; return item . data as T [ ] ; } param item returns isExpired ( item ) { const now = new Date ( ) ; return ! ! item . updatedAt && differenceInSeconds ( now , item . updatedAt ) > POOL_CACHE_EXPIRE_TIME ; } private clearPool ( ) { let beCleaned = [ ] ; const entities = Array . from ( this . _pool . entries ( ) ) ; beCleaned = entities . filter ( ( x ) => this . isExpired ( x [ 1 ] ) ) ; if ( entities . length > POOL_CACHE_MAX_CAPACITY ) { const picks = entities . sort ( ( a , b ) => compareAsc ( a [ 1 ] . pickedAt || a [ 1 ] . createdAt , b [ 1 ] . pickedAt || b [ 1 ] . createdAt ) ) . slice ( 0 , entities . length - POOL_CACHE_MAX_CAPACITY ) ; beCleaned = [ ... beCleaned , ... picks ] ; } beCleaned . forEach ( ( x ) => this . _pool . delete ( x [ 0 ] ) ) ; } } const SOCKET_POINT = process . env . NODE_ENV === 'production' && process . env . channel === 'stable' ? 'wss://hyper-proxy.r2d2.to' : 'wss://hyper-proxy-development.mask-reverse-proxy.workers.dev' ; enum SocketState { CONNECTING = 0 , OPEN = 1 , CLOSING = 2 , CLOSED = 3 } returns function getProxyWebsocketInstanceWrapper ( ) { let cachedInstance ; const createNewInstance = async ( notify ? ) => { cachedInstance = new ProviderProxy ( SOCKET_POINT , notify ) ; await cachedInstance . waitingOpen ( ) ; cachedInstance . registerMessage ( ) ; } ; return async ( notify ? ) => { if ( cachedInstance ) return cachedInstance ; await createNewInstance ( notify ) ; return cachedInstance ; } ; } export const getProxyWebsocketInstance = getProxyWebsocketInstanceWrapper ( ) ; param endPoint returns export const getWebSocketInstance = async ( endPoint ? ) => { const socket = new WebSocket ( endPoint ?? SOCKET_POINT ) ; const waitingOpen = ( ) => { return new Promise < void > ( ( resolve , reject ) => { socket . addEventListener ( 'open' , ( ) => resolve ( ) ) ; socket . addEventListener ( 'error' , ( ) => reject ( ) ) ; } ) ; } ; await waitingOpen ( ) ; return socket ; } ; param message param endPoint returns export const sendMessageToProxy = async < T > ( message , endPoint ? ) => { let data = [ ] ; const socket = await getWebSocketInstance ( SOCKET_POINT ?? endPoint ) ; const sendPromise = ( ) => new Promise < T [ ] > ( ( resolve , reject ) => { socket . addEventListener ( 'message' , ( event ) => { const { results = [ ] , error } = JSON . parse ( event . data ) as PayloadMessage < T > ; if ( error ) { socket . close ( ) ; reject ( error ) ; } if ( results . length === 0 ) { socket . close ( ) ; resolve ( data ) ; } data = [ ... data , ... results ] ; } ) ; socket . send ( JSON . stringify ( message ) ) ; } ) ; return sendPromise ( ) ; } ;