http API CALL from class

import {WebPartContext} from "@microsoft/sp-webpart-base";
import { EnvironmentType } from "@microsoft/sp-core-library";
import { HttpClient } from "@microsoft/sp-http";

export class LotusServiceManager{
    public context: WebPartContext;
    public environmentType: EnvironmentType;


    public Setup(context: WebPartContext, environmentType: EnvironmentType):void {
        this.context = context;
        this.environmentType = environmentType;
    }

    public checkURL(LotusURL: string): Promise<any> {
        return this.context.httpClient.get(`${LotusURL}`,
        HttpClient.configurations.v1).then(response => {
            return response.json();
        }).catch(error => {
            return Promise.reject(error);
        });
    }



}

const LotusService = new LotusServiceManager();
export default LotusService;