Angular2: Very vague error when using angular-http

Question

I am busy with a small ngCli angular2 web app where i'm trying to use a RestService to post to a API... I have a few other get functions in the Rest Service where I use Headers instead of RequestOptions which works fine. I am trying to use RequestOptions with the post method but keep getting the following error in Chrome dev tools console. (I tried using RequestOptions instead of headers with my working get requests and getting the same error). Any idea what could be causing this? Am I using RequestOptions correctly?

my error:

zone.js:1725
OPTIONS
http://10.60.160.34/BRMServices/WebEnquiry/StockTake/AddToStockTake
net::ERR_CONNECTION_RESET

table with 4 columns and 32 rows
 
scheduleTask
@ 
zone.js:1725  
ZoneDelegate.scheduleTask
@
zone.js:255  
Zone.scheduleMacroTask
@
zone.js:168  
(anonymous)
@
zone.js:1749  
send
@
VM384:3  
(anonymous)
@
xhr_backend.js:125  
Observable.subscribe
@
Observable.js:45  
MapOperator.call
@
map.js:54  
Observable.subscribe
@
Observable.js:42  
CatchOperator.call
@
catch.js:31  
Observable.subscribe
@
Observable.js:42  
StockTakeComponent.submitStockTake
@
stock-take.component.ts:45  
StockTakeComponent.doStockTake
@
stock-take.component.ts:38  
View_StockTakeComponent0.handleEvent_10
@
component.ngfactory.js:281  
(anonymous)
@
view.js:664  
schedulerFn
@
async.js:103  
SafeSubscriber.__tryOrUnsub
@
Subscriber.js:223  
SafeSubscriber.next
@
Subscriber.js:172  
Subscriber._next
@
Subscriber.js:125  
Subscriber.next
@
Subscriber.js:89  
Subject.next
@
Subject.js:55  
EventEmitter.emit
@
async.js:77  
FormGroupDirective.onSubmit
@
form_group_directive.js:190  
Wrapper_FormGroupDirective.handleEvent
@
wrapper.ngfactory.js:42  
View_StockTakeComponent0.handleEvent_10
@
component.ngfactory.js:279  
(anonymous)
@
view.js:664  
(anonymous)
@
dom_renderer.js:490  
ZoneDelegate.invokeTask
@
zone.js:275  
onInvokeTask
@
ng_zone.js:260  
ZoneDelegate.invokeTask
@
zone.js:274  
Zone.runTask
@
zone.js:151  
ZoneTask.invoke
@
zone.js:345
table end


my Restservice.ts:

import { Injectable } from '@angular/core';
import { Http, Headers, Response, RequestOptions, URLSearchParams  } from "@angular/http";
import { Observable } from  'rxjs/Rx';

import { ProductModel } from '../models/product.model';
import { StockTransactionModel } from '../models/stock-transaction.model';
import { StockTakeModel } from '../models/stock-take.model';


@Injectable()
export class RestService {
private API_URL: string;
private localIP: string;
private headers: Headers;
private options: RequestOptions;



  constructor(private http: Http){    
  }

  init(ip: string): void {        
      this.localIP = ip;
      this.headers = new Headers({ 'Content-Type': 'application/json' });
      this.options = new RequestOptions({ headers: this.headers });
      this.API_URL = "http://" + this.localIP + "/BRMServices/WebEnquiry/";
  }

  getProduct(barcode: string): Observable<ProductModel> {         
      return this.http.get(this.API_URL + "/POSEnquiry/" + barcode, this.headers)
      .map((res: Response) => res.json())
      .catch((error: any) => Observable.throw(error.json().error || 'Server error'));
  }  

  getStockTransactions(productCode: string) : Observable<StockTransactionModel[]> {
      return this.http.get(this.API_URL + "StockTransactions/" + productCode, this.headers)
      .map((res: Response) => res.json())
      .catch((error: any ) => Observable.throw(error.json().error || 'server error'));    
  }

  postStockTake(stockTakeModel: StockTakeModel) : Observable<Response> {
      console.log(JSON.stringify(stockTakeModel));

        return this.http.post(this.API_URL + "StockTake/AddToStockTake",  {stockTakeModel}, {headers: this.headers})
        .map((res: Response) => res.json())
        .catch((error: any) => Observable.throw(error.json().error || 'server error'));
  }

  ping(ip: string) : Observable<Response> {
      let tempApiUrl: string = "http://" + ip + "/BRMServices/WebEnquiry/ping";
      return this.http.get(tempApiUrl, this.headers)
      .map((res: Response) => res.json())
      .catch((error: any) => Observable.throw(error.json().error || 'server error'));
  }

}

Update: from chrome://net-internals I get:

http://10.60.160.34/BRMServices/WebEnquiry/StockTake/AddToStockTake
Start Time: 2017-01-13 14:44:30.800
t=19711 [st=0] +REQUEST_ALIVE  [dt=3]
t=19711 [st=0]    URL_REQUEST_DELEGATE  [dt=0]
t=19711 [st=0]   +URL_REQUEST_START_JOB  [dt=3]
                  --> load_flags = 34624 (DO_NOT_SAVE_COOKIES | DO_NOT_SEND_AUTH_DATA | DO_NOT_SEND_COOKIES | MAYBE_USER_GESTURE | VERIFY_EV_CERT)
                  --> method = "OPTIONS"
                  --> priority = "MEDIUM"
                  --> url = "http://10.60.160.34/BRMServices/WebEnquiry/StockTake/AddToStockTake"
t=19711 [st=0]      URL_REQUEST_DELEGATE  [dt=0]
t=19711 [st=0]      HTTP_CACHE_GET_BACKEND  [dt=0]
t=19711 [st=0]     +HTTP_STREAM_REQUEST  [dt=1]
t=19711 [st=0]        HTTP_STREAM_REQUEST_STARTED_JOB

 --> source_dependency = 6474 (HTTP_STREAM_JOB)

t=19712 [st=1]        HTTP_STREAM_REQUEST_BOUND_TO_JOB

 --> source_dependency = 6474 (HTTP_STREAM_JOB)

t=19712 [st=1]     -HTTP_STREAM_REQUEST
t=19712 [st=1]     +HTTP_TRANSACTION_SEND_REQUEST  [dt=0]
t=19712 [st=1]        HTTP_TRANSACTION_SEND_REQUEST_HEADERS
                      --> OPTIONS /BRMServices/WebEnquiry/StockTake/AddToStockTake HTTP/1.1
                          Host: 10.60.160.34
                          Connection: keep-alive
                          Access-Control-Request-Method: POST
                          Origin: http://localhost:4200
                          User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.87 Safari/537.36
                          Access-Control-Request-Headers: content-type
                          Accept: */*
                          Referer: http://localhost:4200/stockTake
                          Accept-Encoding: gzip, deflate, sdch
                          Accept-Language: en-US,en;q=0.8
t=19712 [st=1]     -HTTP_TRANSACTION_SEND_REQUEST
t=19712 [st=1]     +HTTP_TRANSACTION_READ_HEADERS  [dt=2]
t=19712 [st=1]        HTTP_STREAM_PARSER_READ_HEADERS  [dt=2]
                      --> net_error = -101 (ERR_CONNECTION_RESET)
t=19714 [st=3]     -HTTP_TRANSACTION_READ_HEADERS
                    --> net_error = -101 (ERR_CONNECTION_RESET)
t=19714 [st=3]   -URL_REQUEST_START_JOB
                  --> net_error = -101 (ERR_CONNECTION_RESET)
t=19714 [st=3]    URL_REQUEST_DELEGATE  [dt=0]
t=19714 [st=3] -REQUEST_ALIVE
                --> net_error = -101 (ERR_CONNECTION_RESET)

Answer 1

The third argument of the post method is a RequestOptionsArgs, not a RequestOptions.

Doc of Http API