Rails URL routing and grouping posts based on topic - ruby-on-rails

Question

I am new to rails I created post model and posts_controller which has Name:string, EMail:string, Message:text, topic_id:integer columns using scaffold.
I also created a topic model and topics_controller which has Topic_Name:string in it.
I provided the relationship among the models as follows:
class Topic < ActiveRecord::Base
has_many :posts, foreign_key: 'topic_id'
end
class Post < ActiveRecord::Base
belongs_to :topic
end
In routes.db I created the nested resources as:
resources :topics do
resources :posts
end
topics_controller.rb code:
class TopicsController < ApplicationController
before_action :set_topic, only: [:show, :edit, :update, :destroy]
# GET /topics
# GET /topics.json
def index
#topics = Topic.all
end
# GET /topics/1
# GET /topics/1.json
def show
end
# GET /topics/new
def new
#topic = Topic.new
end
# GET /topics/1/edit
def edit
end
# POST /topics
# POST /topics.json
def create
#topic = Topic.new(topic_params)
respond_to do |format|
if #topic.save
format.html { redirect_to #topic, notice: 'Topic was successfully created.' }
format.json { render :show, status: :created, location: #topic }
else
format.html { render :new }
format.json { render json: #topic.errors, status: :unprocessable_entity }
end
end
end
# PATCH/PUT /topics/1
# PATCH/PUT /topics/1.json
def update
respond_to do |format|
if #topic.update(topic_params)
format.html { redirect_to #topic, notice: 'Topic was successfully updated.' }
format.json { render :show, status: :ok, location: #topic }
else
format.html { render :edit }
format.json { render json: #topic.errors, status: :unprocessable_entity }
end
end
end
# DELETE /topics/1
# DELETE /topics/1.json
def destroy
#topic.destroy
respond_to do |format|
format.html { redirect_to topics_url, notice: 'Topic was successfully destroyed.' }
format.json { head :no_content }
end
end
private
# Use callbacks to share common setup or constraints between actions.
def set_topic
#topic = Topic.find(params[:id])
end
# Never trust parameters from the scary internet, only allow the white list through.
def topic_params
params.require(:topic).permit(:Name)
end
end
posts_controller code:
class PostsController < ApplicationController
before_action :set_post, only: [:show, :edit, :update, :destroy]
# GET /posts
# GET /posts.json
def index
#posts = Post.all
end
# GET /posts/1
# GET /posts/1.json
def show
end
# GET /posts/new
def new
#post = Post.new
end
# GET /posts/1/edit
def edit
end
# POST /posts
# POST /posts.json
def create
#post = Post.new(post_params)
respond_to do |format|
if #post.save
format.html { redirect_to #post, notice: 'Post was successfully created.' }
format.json { render :show, status: :created, location: #post }
else
format.html { render :new }
format.json { render json: #post.errors, status: :unprocessable_entity }
end
end
end
# PATCH/PUT /posts/1
# PATCH/PUT /posts/1.json
def update
respond_to do |format|
if #post.update(post_params)
format.html { redirect_to #post, notice: 'Post was successfully updated.' }
format.json { render :show, status: :ok, location: #post }
else
format.html { render :edit }
format.json { render json: #post.errors, status: :unprocessable_entity }
end
end
end
# DELETE /posts/1
# DELETE /posts/1.json
def destroy
#post.destroy
respond_to do |format|
format.html { redirect_to posts_url, notice: 'Post was successfully destroyed.' }
format.json { head :no_content }
end
end
private
# Use callbacks to share common setup or constraints between actions.
def set_post
#post = Post.find(params[:id])
end
# Never trust parameters from the scary internet, only allow the white list through.
def post_params
params.require(:post).permit(:Name, :Email, :Message, :topic_id)
end
end
I need to group posts using the topic. i.e., On clicking show on a particular topic it should go to the URL /topics/<topic_id>/posts where it should lists all posts related to that topic and I can create/delete posts belongs to that topic.
Can anyone help doing this..
Thank you..

Answer 1

Your question should be more direct, there's a lot of information that aren't related to the problem (the attributes names, for example), and your goal isn't clear enough.
It seems that you just want to setup the routes, right? You already have all posts related to that topic though the association: topic.posts. You just need to setup nested resource routes for posts:
resources :topics do
resources :posts
end
Also, you don't need the foreign_key option since you're using the naming conventions. It seems as well that you named some attributes in upper case, they should be name, email and message.
UPDATE:
In the index action, since you want posts belonging to one topic, you need to scope the #posts instance variable. Since you're using nested resources, you have the parameter params[:topic_id], so just fetch the topic with #topic = Topic.find(params[:topic_id]), then scope the association with #posts = #topic.posts. You'll need to do the same for every other action. I recommend that you read a little about associations in Rails, you'll probably need to use methods like #topic.posts.build and #topic.posts.find(params[:id]).

Answer 2

I found the solution for this problem in this link: Nested resources
Download the source code and find the solution...