Method depthStream

src/node-binance-api.ts:6414–6430

* Websocket depth chart * @param {array/string} symbols - an array or string of symbols to query * @param {function} callback - callback function * @return {string} the websocket endpoint

(symbols: string[] | string, callback: Callback)

     * @return {string} the websocket endpoint
     */
    depthStream(symbols: string[] | string, callback: Callback) {
        const reconnect = () => {
            if (this.Options.reconnect) this.depthStream(symbols, callback);
        };
        let subscription;
        if (Array.isArray(symbols)) {
            if (!this.isArrayUnique(symbols)) throw Error('depth: "symbols" cannot contain duplicate elements.');
            const streams = symbols.map(function (symbol) {
                return symbol.toLowerCase() + '@depth@100ms';
            });
            subscription = this.subscribeCombined(streams, callback, reconnect);
        } else {
            const symbol = symbols;
            subscription = this.subscribe(symbol.toLowerCase() + '@depth@100ms', callback, reconnect);
        }
        return (subscription as any).url;
    }

    async mapLimit(array, limit, asyncFn) {
        const results = [];