How to set different type of headers in every HTTP api call?

Question

We have different types of microservice running on different machines and I would like to connect to them. But since all microservice is having their own headers I need to pass them accordingly in my Angular application.

I have written an interceptor to intercept and attach the headers and send the request to server as shown below

import { Injectable } from '@angular/core';
import { HttpInterceptor, HttpRequest, HttpHandler, HttpEvent  } from '@angular/common/http';
import { Observable } from 'rxjs';

export class JwtInterceptor implements HttpInterceptor {

    intercept(req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
            req = req.clone({
                setHeaders: {
                    Authorization: `Bearer ${----token-----}`,
                    'api-version': '1.0.0'
                }
            });

            return next.handle(req);
    }

}

but I would like to set respective headers based on the type of microservice that I would like to connect with.

What would be the best possible approach to handle this ?

Answer 1

At a very generic level, we do something to what @riorudo suggested in his comment.

We set up an array of configuration object conceptually something like this:

[
  {  method: 'GET', urlToIntercept: '/something'},
  {  method: 'POST', urlToIntercept: '/somethingElse' }
  // etc.. etc...
]

You could hard code this as a config in the interceptor or pass it in as a service.

The interceptor code can do something along the lines of:

if (interceptableMethodList.find(element => request.urlToIntercept.includes(element.url) && request.method.toLowerCase() === element.method)) {
   // add header
}