How to Build a Forum with Jumpstart Pro

Hey Guys,

I'm following along with the How to Build a Forum with Jumpstart Pro video (https://www.youtube.com/watch?v=ZSom4V-nYxA&t=903s) and I am running into the error "The action 'create' could not be found for PostsController" when trying to reply to a discussion. Here are my files:

posts_controller.rb

class PostsController < ApplicationController
  before_action :set_discussion
  before_action :set_post, only[:edit, :update, :destroy]

  def create
    @post = @discussion.posts.new(post_params)
    @post.user = current_user

    if @post.save
      redirect_to discussion_path(@discussion, anchor: @post.id)
    else
      redirect_to @discussion, alert: @post.errors.full_messages.first
    end
  end

  def edit
  end

  def update
    if @post.update(post_params)
      redirect_to discussion_path(@discussion, anchor: @post.id)
    else
      redirect_to @discussion, alert: @post.errors.full_messages.first
    end
  end

  def destroy
    @post.destroy
    redirect_to @discussion
  end

  private

  def set_discussion
    @discussion = Discussion.find(params[:discussion_id])
  end

  def set_post
    @post = @discussion.posts.find_by!(id: params[:id], user: current_user)
  end

  def post_params
    params.require(:post).permit(:body)
  end
end

_post.html.erb

<div id="<%= dom_id(post) %>" class="flex pb-6 border-b mb-6 group">
  <div class="mr-6">
    <%= image_tag avatar_url_for(post.user), class: "rounded-full", height: 40, width: 40 %>
  </div>

  <div class="flex-1">
    <div class="mb-4">
      <span class="font-semibold"><%= post.user.name %></span>
      <span class> <%= link_to local_time_ago(post.created_at), discussion_path(@discussion, anchor: post.id), class: "ml-1 hover:underline text-gray-700"  %></span>
      <% if user_signed_in? && current_user == post.user %>
        <span class="text-gray-600">-</span> <%= link_to "Edit", edit_discussion_post_path(@discussion, post), class: "ml-1 hover:underline text-gray-700" %>
      <% end %>
    </div>

    <div>
      <%= post.body %>
    </div>
  </div>
</div>

edit.html.erb

<div class="container mx-auto my-8 px-4 max-w-3xl bg-white shadow p-8">
  <h1 class="h2 mb-6">Editing Post</h1>

  <%= form_with model: [@discussion, @post], class: "flex-1" do |form| %>
    <div class="form-group">
      <%= form.rich_text_area :body, data: { controller: "mentions", target: "mentions.field" } %>
    </div>

    <div class="form-group flex justify-between">
      <%= link_to "Delete", [@discussion, @post], method: :delete, class: "btn btn-link text-red-700", data: { remote: true, confirm: "Are you sure?" } %>
      <div>
        <%= link_to "Cancel", @discussion, class: "btn btn-link" %>
        <%= form.submit "Save Changes", class: "btn btn-tertiary", data: { disable_with: "Saving..." } %>
      </div>
    </div>
  <% end %>
</div>

discussion_controller.rb

class DiscussionsController < ApplicationController
  before_action :authenticate_user!, except: [:index, :show]
  before_action :set_discussion, only: [:show, :edit, :update, :destroy]

  # GET /discussions
  def index
    @pagy, @discussions = pagy(Discussion.all)
  end

  # GET /discussions/1
  def show
  end

  # GET /discussions/new
  def new
    @discussion = Discussion.new
    @discussion.posts.new
  end

  # GET /discussions/1/edit
  def edit
  end

  # POST /discussions
  def create
    @discussion = current_user.discussions.new(discussion_params)
    @discussion.posts.each{ |post| post.user = current_user }

    if @discussion.save
      redirect_to @discussion, notice: 'Discussion was successfully created.'
    else
      render :new
    end
  end

  # PATCH/PUT /discussions/1
  def update
    if @discussion.update(discussion_params)
      redirect_to @discussion, notice: 'Discussion was successfully updated.'
    else
      render :edit
    end
  end

  # DELETE /discussions/1
  def destroy
    @discussion.destroy
    redirect_to discussions_url, notice: 'Discussion was successfully destroyed.'
  end

  private
    # Use callbacks to share common setup or constraints between actions.
    def set_discussion
      @discussion = Discussion.find(params[:id])
    end

    # Only allow a trusted parameter "white list" through.
    def discussion_params
      params.require(:discussion).permit(:user_id, :title, posts_attributes: [:body])
    end
end

Here are my routes:

 # For details on the DSL available within this file, see http://guides.rubyonrails.org/routing.html

Rails.application.routes.draw do

  resources :discussions do
    resources :posts
  end
  # Jumpstart views
  if Rails.env.development? || Rails.env.test?
    mount Jumpstart::Engine, at: '/jumpstart'
    mount LetterOpenerWeb::Engine, at: "/letter_opener"
  end

  # Administrate
  authenticated :user, lambda { |u| u.admin? } do
    namespace :admin do
      if defined?(Sidekiq)
        require 'sidekiq/web'
        mount Sidekiq::Web => '/sidekiq'
      end

      resources :announcements
      resources :users
      namespace :user do
        resources :connected_accounts
      end
      resources :teams
      resources :team_members
      resources :plans
      namespace :pay do
        resources :charges
        resources :subscriptions
      end

      root to: "dashboard#show"
    end
  end

  # User account
  devise_for :users,
             controllers: {
               masquerades: 'jumpstart/masquerades',
               omniauth_callbacks: 'users/omniauth_callbacks',
               registrations: 'users/registrations',
             }

  resources :announcements, only: [:index]
  resources :teams do
    member do
      patch :switch
    end

    resources :team_members, path: :members
  end

  # Payments
  resource :card
  resource :subscription do
    patch :info
    patch :resume
  end
  resources :charges
  namespace :account do
    resource :password
  end

  resources :users
  namespace :user, module: :users do
    resources :connected_accounts
  end

  scope controller: :static do
    get :about
    get :terms
    get :privacy
    get :pricing
  end

  authenticated :user do
    root to: "dashboard#show", as: :user_root
  end

  # Public marketing homepage
  root to: "static#index"
end

What do you see for rails routes -c posts?

Here is what it's showing:

  Prefix Verb   URI Pattern                                          Controller#Action
    discussion_posts GET    /discussions/:discussion_id/posts(.:format)          posts#index
                     POST   /discussions/:discussion_id/posts(.:format)          posts#create
 new_discussion_post GET    /discussions/:discussion_id/posts/new(.:format)      posts#new
edit_discussion_post GET    /discussions/:discussion_id/posts/:id/edit(.:format) posts#edit
     discussion_post GET    /discussions/:discussion_id/posts/:id(.:format)      posts#show
                     PATCH  /discussions/:discussion_id/posts/:id(.:format)      posts#update
                     PUT    /discussions/:discussion_id/posts/:id(.:format)      posts#update
                     DELETE /discussions/:discussion_id/posts/:id(.:format)      posts#destroy