How dis you get oauth-1.0a and crypto to work with WP-API - ionic2

Question

I am using crypto and oauth-1.0a from nmp in ionic2 application. I want to access WP-API which is correctly set to handle authentication, I tested this using Postman.
Http.Get results in the following error:
{
"_body": {
"isTrusted": true
},
"status": 0,
"ok": false,
"statusText": "",
"headers": {},
"type": 3,
"url": null
}
The options generated that I pass as argument to Http.Get are as follows:
{“method”:0,“headers”:{“Authorization”:“OAuth oauth_consumer_key=”",
oauth_nonce=“jSZGPwkj4quRGMb0bhBLYKwmc3BGfrQw”, oauth_signature=“x3zseS3XTFBLMsNDLXC4byn2UDI%3D”,
oauth_signature_method=“HMAC-SHA1”, oauth_timestamp=“1522414816”,
oauth_token="",
oauth_version=“1.0"”},“body”:null,“url”:"",“params”:{“rawParams”:"",“queryEncoder”:{},“paramsMap”:{}},“withCredentials”:null,“responseType”:null}
Part of code:
this.oauth = new OAuth({
consumer: {
key: this.apiconstant.consumerkey,
secret: this.apiconstant.consumersecret
},
signature_method: ‘HMAC-SHA1’,
hash_function: hash_function_sha1,
realm:’’
});
let request_data = {
url: ‘’,
method: ‘GET’
};
let token={
key: this.apiconstant.token,
secret: this.apiconstant.tokensecret
}
//This part doesn’t seem to work
this.authkey = this.oauth.authorize(request_data,token);
this.keyoauth = new URLSearchParams();
for (let param in this.authkey) {
this.keyoauth.set(param, this.authkey[param]);
}
let options = new RequestOptions({
method: ‘GET’,//request_data.method
url: ‘’,
headers: this.oauth.toHeader(this.oauth.authorize(request_data,token)),
search: this.keyoauth
});
this.http.get(’’,options)
.map(res => res.json()).subscribe(data=>{
console.log(‘Resulting data’ + JSON.stringify(data));
},
error=>{
console.log(‘Got error’+JSON.stringify(error));
});
//Error part executed
What am I missing here? I’m testing my app on android device. Without authentication I get desired results from the WP-API (Wordpress), that is if the Oauth is disabled on WP-API.
Please help! This is my second day on this. I should also let you know I’m new on these technologies but I’m able to research and understand how they work.