posts_controller.rb

class PostsController < ApplicationController
  include ActionController::Live


  before_filter :authenticate_user!, only: [:new, :create, :edit, :update, :destroy]
  before_filter :set_post, only: [:show, :edit, :update, :destroy]

  # GET /posts/:slug
  def show
  end

  # GET /posts/new
  def new
    @post = Post.new
  end

  # GET /posts/:slug/edit
  def edit
  end

  # POST /posts
  def create
    response.headers["Content-Type"] = "text/javascript"
    @post = Post.new(post_params)
    @post.user = current_user

    if @post.save
      $redis.publish('messages.create', @post.created_at)

      flash[:notice] = 'Post was successfully created.'
      if request.env['HTTP_REFERER'] == root_url
        redirect_to :back
      else
        redirect_to @post
      end
    else
      render action: 'new'
    end
  end

  # PATCH/PUT /posts/:slug
  def update
    if @post.update(post_params)
      redirect_to @post, notice: 'Post was successfully updated.'
    else
      redirect_to :back
    end
  end

  # DELETE /posts/:slug
  def destroy
    @post.destroy
    redirect_to posts_url, notice: 'Post was successfully destroyed.'
  end


  # GET /posts/events
  #
  def events
    response.headers["Content-Type"] = "text/event-stream"
    redis = Redis.new
    redis.psubscribe('messages.*') do |on|
      on.pmessage do |pattern, event, data|
        post = current_user.followees_latest_posts(where: { :created_at.gte => data }).first

        if post.present?
          response.stream.write("event: #{event}\n")
          response.stream.write("data: #{post.to_json}\n\n")
        end
      end
    end
  rescue IOError
    logger.info("Stream closed")
  ensure
    redis.quit
    response.stream.close
  end

  private

  # Use callbacks to share common setup or constraints between actions.
  def set_post
    @post = Post.where(slug: params[:slug]).first
  end

  # Only allow a trusted parameter "white list" through.
  def post_params
    params.require(:post).permit(:body, :headline)
  end
end