ruby on rails - How to get a timeline of posts of only people someone follows -

i'm trying instagram can see images of people follow. user can follow user , create new posts.

this have following , unfollowing in users controller.

def following   @user = user.find(params[:id])   current_user.mark_as_following @user    respond_to |format|     format.html {redirect_to @user}     format.js   end end  def unfollow   @user = user.find(params[:id])   @user.unmark :following, :by => current_user    respond_to |format|     format.html {redirect_to @user}     format.js   end end 

here my posts controller

class postscontroller < applicationcontroller    load_and_authorize_resource     def show       @post = post.find(params[:id])    end     def new       @post = post.new    end     def create        @post.user_id = current_user.id        if @post.save           redirect_to @post        else           render :new        end    end     def edit        @post = post.find(params[:id])    end     def update        @post = post.find(params[:id])        if @post.update_attributes(update_params)            redirect_to @post        else            render :edit        end    end     private        def update_params            params.require(:post).permit(:caption, :image)        end         def create_params            params.require(:post).permit(:caption, :user_id, :image)        end  end 

you can create controller this

class followingpostscontroller < applicationcontroller     def index       @posts = current_user.following_posts    end end 

and in user model

class user < activerecord::base   def following_posts       #assuming following_users returns list of following users       self.following_users.map{ |user| user.posts }.flatten(1)   end end 

or can list of posts :

post.where(user_id: self.following_users.ids)