title: Is there a way to add query parameter to every request with Retrofit 2?
body: <p>I need to add a query parameter to every request made by Retrofit 2.0.0-beta2 library. I found <a href="https://stackoverflow.com/questions/17580223/">this solution</a> for Retrofit 1.9, but how to add <code>RequestInterceptor</code> in newest library version?</p>
  
  <p>My interface:</p>
  
  <pre><code>@GET("user/{id}")
  Call&lt;User&gt; getUser(@Path("id")long id);
  
  @GET("users/")
  Call&lt;List&lt;User&gt;&gt; getUser();
  </code></pre>
  
  <p>Client:</p>
  
  <pre><code>Retrofit retrofit = new Retrofit.Builder()
                      .baseUrl(BASE_URL)
                      .addConverterFactory(GsonConverterFactory.create())
                      .client(CLIENT)  // custom OkHTTP Client
                      .build();
  service = retrofit.create(userService.class);
  </code></pre>