angular: Dependency injection not working for custom RequestOptions class when making a post request to remote url

Overriding merge in RequestOptions is not a supported usage of the API. There will be a much better way of manipulating request options in upcoming HTTP APIs (interceptors).

@mattheiler I am having the same issue and came to the same conclusion. How did you workaround this issue ? @DzmitryShylovich what would be the (angular) way to change an http header ?

Merge seems like it should be a utility rather than behavior. To get what I had wanted, I’d have to override merge like this:

@Injectable()
export class CustomRequestOptions extends BaseRequestOptions {

    ...

    merge(args: RequestOptionsArgs): CustomRequestOptions {

        var options = super.merge(args);

        var element = document.getElementsByTagName('base').item(0);
        if (element != null)
            options.url = element.href + (options.url || '');

        var clone = new CustomRequestOptions();
 
        // i can't return the result of super.merge(), since it is a new instance of the wrong type
        // i have to re-map everything
        // consumers shouldn't have to babysit this mapping...
        // we seem to be mixing cloning with merging

        clone.body = options.body;
        clone.headers = options.headers;
        clone.method = options.method;
        clone.responseType = options.responseType;
        clone.search = options.search;
        clone.url = options.url;
        clone.withCredentials = options.withCredentials;

        return clone;
    }

}

This issue is caused by the RequestOptions.merge() method - it creates a new instance of type RequestOptions, rather than the injected type. The Http service calls this method when merging options for the POST, PUT, and PATCH methods. IMO, either make RequestOptions follow the prototype pattern, or remove that RequestOptions.merge() and change the POST, PUT, and PATCH methods in the Http service.