AuthenticationService.java

package com.betaseries.betaseries.authentication.webservice;

import com.betaseries.betaseries.authentication.model.Authentication;

import retrofit.http.Field;
import retrofit.http.FormUrlEncoded;
import retrofit.http.POST;
import rx.Observable;

public interface AuthenticationService {

    @FormUrlEncoded
    @POST("/members/auth")
    Observable<Authentication> authentifier(@Field("login") String login, @Field("password") String passwordMD5);
}