Adding headers in DataStore

[Tinostarn]

Hello,

I'm trying to add headers to provide a token access to my API. The guide gives this line :

this.datastore.headers = new Headers({'Authorization': 'Bearer ' + accessToken});

and 2 other examples, but they seem to be on the consumer components side. I'd like to avoid specifying headers it in each of my HTTP calls.
First I tried to add it in a "headers" key within the @JsonApiDatastoreConfig decorator, but didn't work.

Then I tried to put it in my Datastore service, in the constructor :

export class Datastore extends JsonApiDatastore {

    constructor(http: Http) { 
        super(http);
        this.headers = new Headers({ 'Authorization': 'Bearer ' + localStorage.getItem('access_token')});
    }

}

Now something strange, each time I validate my form and check the headers that are sent to the server, it turns out that the "accept" and "Content-type" keys are repeated.
Example, if I submit my form 3 times, I get on the third call :

accept:application/vnd.api+json,application/vnd.api+json,application/vnd.api+json
authorization:Bearer NDgyZGQ1YTIzMTZiNjg4MzY0ZDVmOTk1NzkyZjZjZGNmZjIyZDZmMDU2YzY0NThmYzc5OGM1ZmE2ZTcxZWE3ZA
content-type:application/vnd.api+json,application/vnd.api+json,application/vnd.api+json

Does it come from the way I add my header ?
Just for information, when I submit a form, server doesn't return a valid response yet (test purpose), so the app is assumed to be crashed.

Thx for your help

[jamesdixon]

@supertino7 I'm also trying to do this in the constructor, but unfortunately, at the time the service/provider is initialized, the token isn't available yet and therefore headers are never set. How are you handling this?

Thank you!