Angular 6 Unable to get data from external server API using proxy

Question

I'm using local angular app and I get problem to get data from API on external server. I tried to use proxy, so I create file proxyconfig.json and I included it in command line via

ng serve --proxy-config proxyconfig.json

And here is content:

{
    "/api/*": {
    "target": "https://bittrex.com/api/v1.1/public/",
        "secure": false,
        "pathRewrite": {
            "^/api": ""
        },
        "changeOrigin": true
    }
}

I need to pass variables so I created service OrderBookService :

import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import { Observable } from 'rxjs';
import { OrderBook } from './order-book.model';


@Injectable({
    providedIn: 'root',
  })
export class OrderBookService {
    constructor(private httpClient: HttpClient) {

    }
    getOrderBookBittrex(currency1: string, currency2: string): Observable<OrderBook[]> {
        const url = `http://localhost:4200/api/getorderbook?market=${currency1}-${currency2}&type=both`;
        return this.httpClient.get<OrderBook[]>(url);
    }
}

The problem is when I want to get this data and save it to variable in my component, path is not translating properly: it's sending request to http://localhost:4200/api/getorderbook?market=BTC-LTC&type=both instead of https://bittrex.com/api/v1.1/public/getorderbook?market=BTC-LTC&type=both :

  private getTransfers(): void {
    const currency1 = 'BTC';
    const currency2 = 'LTC';
    this.orderBookService.getOrderBookBittrex(currency1, currency2)
      .subscribe(orders => {
        this.orderBook = orders;
      });
  }

Anybody knows how to do it properly?

It's working fine when I put all path to proxconfig.json like this:

{
    "/api/*": {
        "target": "https://bittrex.com/api/v1.1/public/getorderbook?market=BTC-LTC&type=both",
        "secure": false,
        "pathRewrite": {
            "^/api": ""
        },
        "changeOrigin": true
    }
}

But I need to pass variables.

Answer 1

You code

getOrderBookBittrex(currency1: string, currency2: string): Observable<OrderBook[]> {
    const url = `http://localhost:4200/api/getorderbook?market=${currency1}-${currency2}&type=both`;
    return this.httpClient.get<OrderBook[]>(url);
}

Just change url like

getOrderBookBittrex(currency1: string, currency2: string): Observable<OrderBook[]> {
    const url = `/api/getorderbook?market=${currency1}-${currency2}&type=both`;
    return this.httpClient.get<OrderBook[]>(url);
}

You don't need use http://localhost:4200 in you code.

And "pathRewrite": { "^/api": "" }, don't need too