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A JavaScript / Python / PHP cryptocurrency trading library with support for 130+ exchanges

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'use strict'; // --------------------------------------------------------------------------- const okxRest = require ('../okx.js'); const { AuthenticationError, InvalidNonce } = require ('../base/errors'); const { ArrayCache, ArrayCacheByTimestamp, ArrayCacheBySymbolById } = require ('./base/Cache'); // --------------------------------------------------------------------------- module.exports = class okx extends okxRest { describe () { return this.deepExtend (super.describe (), { 'has': { 'ws': true, 'watchTicker': true, // 'watchTickers': false, // for now 'watchOrderBook': true, 'watchTrades': true, 'watchBalance': true, 'watchOHLCV': true, 'watchOrders': true, }, 'urls': { 'api': { 'ws': { 'public': 'wss://ws.okx.com:8443/ws/v5/public', // wss://wsaws.okx.com:8443/ws/v5/public 'private': 'wss://ws.okx.com:8443/ws/v5/private', // wss://wsaws.okx.com:8443/ws/v5/private }, }, 'test': { 'ws': { 'public': 'wss://wspap.okx.com:8443/ws/v5/public?brokerId=9999', 'private': 'wss://wspap.okx.com:8443/ws/v5/private?brokerId=9999', }, }, }, 'options': { 'watchOrderBook': { // // bbo-tbt // 1. Newly added channel that sends tick-by-tick Level 1 data // 2. All API users can subscribe // 3. Public depth channel, verification not required // // books-l2-tbt // 1. Only users who're VIP5 and above can subscribe // 2. Identity verification required before subscription // // books50-l2-tbt // 1. Only users who're VIP4 and above can subscribe // 2. Identity verification required before subscription // // books // 1. All API users can subscribe // 2. Public depth channel, verification not required // // books5 // 1. All API users can subscribe // 2. Public depth channel, verification not required // 3. Data feeds will be delivered every 100ms (vs. every 200ms now) // 'depth': 'books', }, 'watchBalance': 'spot', // margin, futures, swap 'ws': { // 'inflate': true, }, 'checksum': true, }, 'streaming': { // okex does not support built-in ws protocol-level ping-pong // instead it requires a custom text-based ping-pong 'ping': this.ping, 'keepAlive': 20000, }, }); } async subscribe (access, channel, symbol, params = {}) { await this.loadMarkets (); const url = this.urls['api']['ws'][access]; let messageHash = channel; const firstArgument = { 'channel': channel, }; if (symbol !== undefined) { const market = this.market (symbol); messageHash += ':' + market['id']; firstArgument['instId'] = market['id']; } const request = { 'op': 'subscribe', 'args': [ this.deepExtend (firstArgument, params), ], }; return await this.watch (url, messageHash, request, messageHash); } async watchTrades (symbol, since = undefined, limit = undefined, params = {}) { /** * @method * @name okx#watchTrades * @description get the list of most recent trades for a particular symbol * @param {string} symbol unified symbol of the market to fetch trades for * @param {int|undefined} since timestamp in ms of the earliest trade to fetch * @param {int|undefined} limit the maximum amount of trades to fetch * @param {object} params extra parameters specific to the okx api endpoint * @returns {[object]} a list of [trade structures]{@link https://docs.ccxt.com/en/latest/manual.html?#public-trades} */ await this.loadMarkets (); symbol = this.symbol (symbol); const trades = await this.subscribe ('public', 'trades', symbol, params); if (this.newUpdates) { limit = trades.getLimit (symbol, limit); } return this.filterBySinceLimit (trades, since, limit, 'timestamp', true); } handleTrades (client, message) { // // { // arg: { channel: 'trades', instId: 'BTC-USDT' }, // data: [ // { // instId: 'BTC-USDT', // tradeId: '216970876', // px: '31684.5', // sz: '0.00001186', // side: 'buy', // ts: '1626531038288' // } // ] // } // const arg = this.safeValue (message, 'arg', {}); const channel = this.safeString (arg, 'channel'); const data = this.safeValue (message, 'data', []); const tradesLimit = this.safeInteger (this.options, 'tradesLimit', 1000); for (let i = 0; i < data.length; i++) { const trade = this.parseTrade (data[i]); const symbol = trade['symbol']; const marketId = this.safeString (trade['info'], 'instId'); const messageHash = channel + ':' + marketId; let stored = this.safeValue (this.trades, symbol); if (stored === undefined) { stored = new ArrayCache (tradesLimit); this.trades[symbol] = stored; } stored.append (trade); client.resolve (stored, messageHash); } return message; } async watchTicker (symbol, params = {}) { /** * @method * @name okx#watchTicker * @description watches a price ticker, a statistical calculation with the information calculated over the past 24 hours for a specific market * @param {string} symbol unified symbol of the market to fetch the ticker for * @param {object} params extra parameters specific to the okx api endpoint * @returns {object} a [ticker structure]{@link https://docs.ccxt.com/en/latest/manual.html#ticker-structure} */ return await this.subscribe ('public', 'tickers', symbol, params); } handleTicker (client, message) { // // { // arg: { channel: 'tickers', instId: 'BTC-USDT' }, // data: [ // { // instType: 'SPOT', // instId: 'BTC-USDT', // last: '31500.1', // lastSz: '0.00001754', // askPx: '31500.1', // askSz: '0.00998144', // bidPx: '31500', // bidSz: '3.05652439', // open24h: '31697', // high24h: '32248', // low24h: '31165.6', // sodUtc0: '31385.5', // sodUtc8: '32134.9', // volCcy24h: '503403597.38138519', // vol24h: '15937.10781721', // ts: '1626526618762' // } // ] // } // const arg = this.safeValue (message, 'arg', {}); const channel = this.safeString (arg, 'channel'); const data = this.safeValue (message, 'data', []); for (let i = 0; i < data.length; i++) { const ticker = this.parseTicker (data[i]); const symbol = ticker['symbol']; const marketId = this.safeString (ticker['info'], 'instId'); const messageHash = channel + ':' + marketId; this.tickers[symbol] = ticker; client.resolve (ticker, messageHash); } return message; } async watchOHLCV (symbol, timeframe = '1m', since = undefined, limit = undefined, params = {}) { /** * @method * @name okx#watchOHLCV * @description watches historical candlestick data containing the open, high, low, and close price, and the volume of a market * @param {string} symbol unified symbol of the market to fetch OHLCV data for * @param {string} timeframe the length of time each candle represents * @param {int|undefined} since timestamp in ms of the earliest candle to fetch * @param {int|undefined} limit the maximum amount of candles to fetch * @param {object} params extra parameters specific to the okx api endpoint * @returns {[[int]]} A list of candles ordered as timestamp, open, high, low, close, volume */ await this.loadMarkets (); symbol = this.symbol (symbol); const interval = this.timeframes[timeframe]; const name = 'candle' + interval; const ohlcv = await this.subscribe ('public', name, symbol, params); if (this.newUpdates) { limit = ohlcv.getLimit (symbol, limit); } return this.filterBySinceLimit (ohlcv, since, limit, 0, true); } handleOHLCV (client, message) { // // { // arg: { channel: 'candle1m', instId: 'BTC-USDT' }, // data: [ // [ // '1626690720000', // '31334', // '31334', // '31334', // '31334', // '0.0077', // '241.2718' // ] // ] // } // const arg = this.safeValue (message, 'arg', {}); const channel = this.safeString (arg, 'channel'); const data = this.safeValue (message, 'data', []); const marketId = this.safeString (arg, 'instId'); const market = this.safeMarket (marketId); const symbol = market['id']; const interval = channel.replace ('candle', ''); // use a reverse lookup in a static map instead const timeframe = this.findTimeframe (interval); for (let i = 0; i < data.length; i++) { const parsed = this.parseOHLCV (data[i], market); this.ohlcvs[symbol] = this.safeValue (this.ohlcvs, symbol, {}); let stored = this.safeValue (this.ohlcvs[symbol], timeframe); if (stored === undefined) { const limit = this.safeInteger (this.options, 'OHLCVLimit', 1000); stored = new ArrayCacheByTimestamp (limit); this.ohlcvs[symbol][timeframe] = stored; } stored.append (parsed); const messageHash = channel + ':' + marketId; client.resolve (stored, messageHash); } } async watchOrderBook (symbol, limit = undefined, params = {}) { /** * @method * @name okx#watchOrderBook * @description watches information on open orders with bid (buy) and ask (sell) prices, volumes and other data * @param {string} symbol unified symbol of the market to fetch the order book for * @param {int|undefined} limit the maximum amount of order book entries to return * @param {object} params extra parameters specific to the okx api endpoint * @returns {object} A dictionary of [order book structures]{@link https://docs.ccxt.com/en/latest/manual.html#order-book-structure} indexed by market symbols */ const options = this.safeValue (this.options, 'watchOrderBook', {}); // // bbo-tbt // 1. Newly added channel that sends tick-by-tick Level 1 data // 2. All API users can subscribe // 3. Public depth channel, verification not required // // books-l2-tbt // 1. Only users who're VIP5 and above can subscribe // 2. Identity verification required before subscription // // books50-l2-tbt // 1. Only users who're VIP4 and above can subscribe // 2. Identity verification required before subscription // // books // 1. All API users can subscribe // 2. Public depth channel, verification not required // // books5 // 1. All API users can subscribe // 2. Public depth channel, verification not required // 3. Data feeds will be delivered every 100ms (vs. every 200ms now) // const depth = this.safeString (options, 'depth', 'books'); const orderbook = await this.subscribe ('public', depth, symbol, params); return orderbook.limit (); } handleDelta (bookside, delta) { // // [ // '31685', // price // '0.78069158', // amount // '0', // liquidated orders // '17' // orders // ] // const price = this.safeFloat (delta, 0); const amount = this.safeFloat (delta, 1); bookside.store (price, amount); } handleDeltas (bookside, deltas) { for (let i = 0; i < deltas.length; i++) { this.handleDelta (bookside, deltas[i]); } } handleOrderBookMessage (client, message, orderbook, messageHash) { // // { // asks: [ // [ '31738.3', '0.05973179', '0', '3' ], // [ '31738.5', '0.11035404', '0', '2' ], // [ '31739.6', '0.01', '0', '1' ], // ], // bids: [ // [ '31738.2', '0.67557666', '0', '9' ], // [ '31738', '0.02466947', '0', '2' ], // [ '31736.3', '0.01705046', '0', '2' ], // ], // instId: 'BTC-USDT', // ts: '1626537446491' // } // const asks = this.safeValue (message, 'asks', []); const bids = this.safeValue (message, 'bids', []); const storedAsks = orderbook['asks']; const storedBids = orderbook['bids']; this.handleDeltas (storedAsks, asks); this.handleDeltas (storedBids, bids); const checksum = this.safeValue (this.options, 'checksum', true); if (checksum) { const asksLength = storedAsks.length; const bidsLength = storedBids.length; const payloadArray = []; for (let i = 0; i < 25; i++) { if (i < bidsLength) { payloadArray.push (this.numberToString (storedBids[i][0])); payloadArray.push (this.numberToString (storedBids[i][1])); } if (i < asksLength) { payloadArray.push (this.numberToString (storedAsks[i][0])); payloadArray.push (this.numberToString (storedAsks[i][1])); } } const payload = payloadArray.join (':'); const responseChecksum = this.safeInteger (message, 'checksum'); const localChecksum = this.crc32 (payload, true); if (responseChecksum !== localChecksum) { const error = new InvalidNonce (this.id + ' invalid checksum'); client.reject (error, messageHash); } } const timestamp = this.safeInteger (message, 'ts'); orderbook['timestamp'] = timestamp; orderbook['datetime'] = this.iso8601 (timestamp); return orderbook; } handleOrderBook (client, message) { // // snapshot // // { // arg: { channel: 'books-l2-tbt', instId: 'BTC-USDT' }, // action: 'snapshot', // data: [ // { // asks: [ // [ '31685', '0.78069158', '0', '17' ], // [ '31685.1', '0.0001', '0', '1' ], // [ '31685.6', '0.04543165', '0', '1' ], // ], // bids: [ // [ '31684.9', '0.01', '0', '1' ], // [ '31682.9', '0.0001', '0', '1' ], // [ '31680.7', '0.01', '0', '1' ], // ], // ts: '1626532416403', // checksum: -1023440116 // } // ] // } // // update // // { // arg: { channel: 'books-l2-tbt', instId: 'BTC-USDT' }, // action: 'update', // data: [ // { // asks: [ // [ '31657.7', '0', '0', '0' ], // [ '31659.7', '0.01', '0', '1' ], // [ '31987.3', '0.01', '0', '1' ] // ], // bids: [ // [ '31642.9', '0.50296385', '0', '4' ], // [ '31639.9', '0', '0', '0' ], // [ '31638.7', '0.01', '0', '1' ], // ], // ts: '1626535709008', // checksum: 830931827 // } // ] // } // // books5 // // { // arg: { channel: 'books5', instId: 'BTC-USDT' }, // data: [ // { // asks: [ // [ '31738.3', '0.05973179', '0', '3' ], // [ '31738.5', '0.11035404', '0', '2' ], // [ '31739.6', '0.01', '0', '1' ], // ], // bids: [ // [ '31738.2', '0.67557666', '0', '9' ], // [ '31738', '0.02466947', '0', '2' ], // [ '31736.3', '0.01705046', '0', '2' ], // ], // instId: 'BTC-USDT', // ts: '1626537446491' // } // ] // } // // bbo-tbt // // { // "arg":{ // "channel":"bbo-tbt", // "instId":"BTC-USDT" // }, // "data":[ // { // "asks":[["36232.2","1.8826134","0","17"]], // "bids":[["36232.1","0.00572212","0","2"]], // "ts":"1651826598363" // } // ] // } // const arg = this.safeValue (message, 'arg', {}); const channel = this.safeString (arg, 'channel'); const action = this.safeString (message, 'action'); const data = this.safeValue (message, 'data', []); const marketId = this.safeString (arg, 'instId'); const market = this.safeMarket (marketId); const symbol = market['symbol']; const depths = { 'bbo-tbt': 1, 'books': 400, 'books5': 5, 'books-l2-tbt': 400, 'books50-l2-tbt': 50, }; const limit = this.safeInteger (depths, channel); const messageHash = channel + ':' + marketId; if (action === 'snapshot') { for (let i = 0; i < data.length; i++) { const update = data[i]; const orderbook = this.orderBook ({}, limit); this.orderbooks[symbol] = orderbook; orderbook['symbol'] = symbol; this.handleOrderBookMessage (client, update, orderbook, messageHash); client.resolve (orderbook, messageHash); } } else if (action === 'update') { if (symbol in this.orderbooks) { const orderbook = this.orderbooks[symbol]; for (let i = 0; i < data.length; i++) { const update = data[i]; this.handleOrderBookMessage (client, update, orderbook, messageHash); client.resolve (orderbook, messageHash); } } } else if ((channel === 'books5') || (channel === 'bbo-tbt')) { let orderbook = this.safeValue (this.orderbooks, symbol); if (orderbook === undefined) { orderbook = this.orderBook ({}, limit); } this.orderbooks[symbol] = orderbook; for (let i = 0; i < data.length; i++) { const update = data[i]; const timestamp = this.safeInteger (update, 'ts'); const snapshot = this.parseOrderBook (update, symbol, timestamp, 'bids', 'asks', 0, 1); orderbook.reset (snapshot); client.resolve (orderbook, messageHash); } } return message; } async authenticate (params = {}) { this.checkRequiredCredentials (); const url = this.urls['api']['ws']['private']; const messageHash = 'login'; const client = this.client (url); let future = this.safeValue (client.subscriptions, messageHash); if (future === undefined) { future = client.future ('authenticated'); const timestamp = this.seconds ().toString (); const method = 'GET'; const path = '/users/self/verify'; const auth = timestamp + method + path; const signature = this.hmac (this.encode (auth), this.encode (this.secret), 'sha256', 'base64'); const request = { 'op': messageHash, 'args': [ { 'apiKey': this.apiKey, 'passphrase': this.password, 'timestamp': timestamp, 'sign': signature, }, ], }; this.spawn (this.watch, url, messageHash, request, messageHash, future); } return await future; } async watchBalance (params = {}) { /** * @method * @name okx#watchBalance * @description query for balance and get the amount of funds available for trading or funds locked in orders * @param {object} params extra parameters specific to the okx api endpoint * @returns {object} a [balance structure]{@link https://docs.ccxt.com/en/latest/manual.html?#balance-structure} */ await this.loadMarkets (); await this.authenticate (); return await this.subscribe ('private', 'account', undefined, params); } handleBalance (client, message) { // // { // arg: { channel: 'account' }, // data: [ // { // adjEq: '', // details: [ // { // availBal: '', // availEq: '8.21009913', // cashBal: '8.21009913', // ccy: 'USDT', // coinUsdPrice: '0.99994', // crossLiab: '', // disEq: '8.2096065240522', // eq: '8.21009913', // eqUsd: '8.2096065240522', // frozenBal: '0', // interest: '', // isoEq: '0', // isoLiab: '', // liab: '', // maxLoan: '', // mgnRatio: '', // notionalLever: '0', // ordFrozen: '0', // twap: '0', // uTime: '1621927314996', // upl: '0' // }, // ], // imr: '', // isoEq: '0', // mgnRatio: '', // mmr: '', // notionalUsd: '', // ordFroz: '', // totalEq: '22.1930992296832', // uTime: '1626692120916' // } // ] // } // const arg = this.safeValue (message, 'arg', {}); const channel = this.safeString (arg, 'channel'); const type = 'spot'; const balance = this.parseTradingBalance (message); const oldBalance = this.safeValue (this.balance, type, {}); const newBalance = this.deepExtend (oldBalance, balance); this.balance[type] = this.safeBalance (newBalance); client.resolve (this.balance[type], channel); } async watchOrders (symbol = undefined, since = undefined, limit = undefined, params = {}) { /** * @method * @name okx#watchOrders * @description watches information on multiple orders made by the user * @param {string|undefined} symbol unified market symbol of the market orders were made in * @param {int|undefined} since the earliest time in ms to fetch orders for * @param {int|undefined} limit the maximum number of orde structures to retrieve * @param {object} params extra parameters specific to the okx api endpoint * @param {bool} params.stop true if fetching trigger or conditional orders * @returns {[object]} a list of [order structures]{@link https://docs.ccxt.com/en/latest/manual.html#order-structure} */ await this.loadMarkets (); await this.authenticate (); // // { // "op": "subscribe", // "args": [ // { // "channel": "orders", // "instType": "FUTURES", // "uly": "BTC-USD", // "instId": "BTC-USD-200329" // } // ] // } // const options = this.safeValue (this.options, 'watchOrders', {}); // By default, receive order updates from any instrument type let type = this.safeString (options, 'type', 'ANY'); type = this.safeString (params, 'type', type); const isStop = this.safeValue (params, 'stop', false); params = this.omit (params, [ 'type', 'stop' ]); let market = undefined; if (symbol !== undefined) { market = this.market (symbol); symbol = market['symbol']; type = market['type']; } if (type === 'future') { type = 'futures'; } const uppercaseType = type.toUpperCase (); const request = { 'instType': uppercaseType, }; const channel = isStop ? 'orders-algo' : 'orders'; const orders = await this.subscribe ('private', channel, symbol, this.extend (request, params)); if (this.newUpdates) { limit = orders.getLimit (symbol, limit); } return this.filterBySymbolSinceLimit (orders, symbol, since, limit, true); } handleOrders (client, message, subscription = undefined) { // // { // "arg":{ // "channel":"orders", // "instType":"SPOT" // }, // "data":[ // { // "accFillSz":"0", // "amendResult":"", // "avgPx":"", // "cTime":"1634548275191", // "category":"normal", // "ccy":"", // "clOrdId":"e847386590ce4dBC330547db94a08ba0", // "code":"0", // "execType":"", // "fee":"0", // "feeCcy":"USDT", // "fillFee":"0", // "fillFeeCcy":"", // "fillNotionalUsd":"", // "fillPx":"", // "fillSz":"0", // "fillTime":"", // "instId":"ETH-USDT", // "instType":"SPOT", // "lever":"", // "msg":"", // "notionalUsd":"451.4516256", // "ordId":"370257534141235201", // "ordType":"limit", // "pnl":"0", // "posSide":"", // "px":"60000", // "rebate":"0", // "rebateCcy":"ETH", // "reqId":"", // "side":"sell", // "slOrdPx":"", // "slTriggerPx":"", // "state":"live", // "sz":"0.007526", // "tag":"", // "tdMode":"cash", // "tgtCcy":"", // "tpOrdPx":"", // "tpTriggerPx":"", // "tradeId":"", // "uTime":"1634548275191" // } // ] // } // const arg = this.safeValue (message, 'arg', {}); const channel = this.safeString (arg, 'channel'); const orders = this.safeValue (message, 'data', []); const ordersLength = orders.length; if (ordersLength > 0) { const limit = this.safeInteger (this.options, 'ordersLimit', 1000); if (this.orders === undefined) { this.orders = new ArrayCacheBySymbolById (limit); } const stored = this.orders; const marketIds = []; const parsed = this.parseOrders (orders); for (let i = 0; i < parsed.length; i++) { const order = parsed[i]; stored.append (order); const symbol = order['symbol']; const market = this.market (symbol); marketIds.push (market['id']); } client.resolve (this.orders, channel); for (let i = 0; i < marketIds.length; i++) { const messageHash = channel + ':' + marketIds[i]; client.resolve (this.orders, messageHash); } } } handleSubscriptionStatus (client, message) { // // { event: 'subscribe', arg: { channel: 'tickers', instId: 'BTC-USDT' } } // // const channel = this.safeString (message, 'channel'); // client.subscriptions[channel] = message; return message; } handleAuthenticate (client, message) { // // { event: 'login', success: true } // client.resolve (message, 'authenticated'); return message; } ping (client) { // okex does not support built-in ws protocol-level ping-pong // instead it requires custom text-based ping-pong return 'ping'; } handlePong (client, message) { client.lastPong = this.milliseconds (); return message; } handleErrorMessage (client, message) { // // { event: 'error', msg: 'Illegal request: {"op":"subscribe","args":["spot/ticker:BTC-USDT"]}', code: '60012' } // { event: 'error', msg: "channel:ticker,instId:BTC-USDT doesn't exist", code: '60018' } // const errorCode = this.safeString (message, 'errorCode'); try { if (errorCode !== undefined) { const feedback = this.id + ' ' + this.json (message); this.throwExactlyMatchedException (this.exceptions['exact'], errorCode, feedback); const messageString = this.safeValue (message, 'message'); if (messageString !== undefined) { this.throwBroadlyMatchedException (this.exceptions['broad'], messageString, feedback); } } } catch (e) { if (e instanceof AuthenticationError) { client.reject (e, 'authenticated'); const method = 'login'; if (method in client.subscriptions) { delete client.subscriptions[method]; } return false; } } return message; } handleMessage (client, message) { if (!this.handleErrorMessage (client, message)) { return; } // // { event: 'subscribe', arg: { channel: 'tickers', instId: 'BTC-USDT' } } // { event: 'login', msg: '', code: '0' } // // { // arg: { channel: 'tickers', instId: 'BTC-USDT' }, // data: [ // { // instType: 'SPOT', // instId: 'BTC-USDT', // last: '31500.1', // lastSz: '0.00001754', // askPx: '31500.1', // askSz: '0.00998144', // bidPx: '31500', // bidSz: '3.05652439', // open24h: '31697', // high24h: '32248', // low24h: '31165.6', // sodUtc0: '31385.5', // sodUtc8: '32134.9', // volCcy24h: '503403597.38138519', // vol24h: '15937.10781721', // ts: '1626526618762' // } // ] // } // // { event: 'error', msg: 'Illegal request: {"op":"subscribe","args":["spot/ticker:BTC-USDT"]}', code: '60012' } // { event: 'error', msg: "channel:ticker,instId:BTC-USDT doesn't exist", code: '60018' } // { event: 'error', msg: 'Invalid OK_ACCESS_KEY', code: '60005' } // { // event: 'error', // msg: 'Illegal request: {"op":"login","args":["de89b035-b233-44b2-9a13-0ccdd00bda0e","7KUcc8YzQhnxBE3K","1626691289","H57N99mBt5NvW8U19FITrPdOxycAERFMaapQWRqLaSE="]}', // code: '60012' // } // // // if (message === 'pong') { return this.handlePong (client, message); } // const table = this.safeString (message, 'table'); // if (table === undefined) { const event = this.safeString (message, 'event'); if (event !== undefined) { const methods = { // 'info': this.handleSystemStatus, // 'book': 'handleOrderBook', 'login': this.handleAuthenticate, 'subscribe': this.handleSubscriptionStatus, }; const method = this.safeValue (methods, event); if (method === undefined) { return message; } else { return method.call (this, client, message); } } else { const arg = this.safeValue (message, 'arg', {}); const channel = this.safeString (arg, 'channel'); const methods = { 'bbo-tbt': this.handleOrderBook, // newly added channel that sends tick-by-tick Level 1 data, all API users can subscribe, public depth channel, verification not required 'books': this.handleOrderBook, // all API users can subscribe, public depth channel, verification not required 'books5': this.handleOrderBook, // all API users can subscribe, public depth channel, verification not required, data feeds will be delivered every 100ms (vs. every 200ms now) 'books50-l2-tbt': this.handleOrderBook, // only users who're VIP4 and above can subscribe, identity verification required before subscription 'books-l2-tbt': this.handleOrderBook, // only users who're VIP5 and above can subscribe, identity verification required before subscription 'tickers': this.handleTicker, 'trades': this.handleTrades, 'account': this.handleBalance, // 'margin_account': this.handleBalance, 'orders': this.handleOrders, 'orders-algo': this.handleOrders, }; const method = this.safeValue (methods, channel); if (method === undefined) { if (channel.indexOf ('candle') === 0) { this.handleOHLCV (client, message); } else { return message; } } else { return method.call (this, client, message); } } } };