no route matches leading to ActionController UrlGenerationError - ruby-on-rails

Question

I have created a ToDoList based off Hartl's tutorial, and following a video and worded tutorial to add a tagging system. I have followed till Section 10, where they asked me to modify my new.html.erb file to the code as shown on the source. To improvise for structural differences in code, I would edit some other files, like in this case, my micropost_form partial instead. Occasionally, I alternated between the code in the video and code in the worded tutorial because some of them would produce error messages or would not produce the required functionality. Here are the files that I think are involved in this question.
_micropost_form.html.erb(The filling up form that would be displayed on the user's home page)
<%= simple_form_for #micropost do |f| %>
<%= render 'shared/error_messages', object: f.object %>
<div class="field">
<%= f.label :content %><br />
<%= f.text_area :content, placeholder: "Add new task..." %>
</div>
<div class="field">
<%= f.label :tag_list, "Tags (separated by commas)" %><br />
<%= f.text_field :tag_list %>
</div>
<%= f.submit "Add Task", class: "btn btn-primary" %>
<% end %>
micropost.html.erb(for showing the individual micro posts)
<li id="micropost-<%= micropost.id %>">
<%= link_to gravatar_for(micropost.user, size: 50), micropost.user %>
<span class="user"><%= link_to micropost.user.name, user_path(micropost.user) %></span>
<span class="content"><%= micropost.content %></span>
<p><small>Tags: <%= raw micropost.tags.map(&:name).map { |t| link_to t, tag_path(t) }.join(', ') %></small</p>
<span class="timestamp">
Posted <%= time_ago_in_words(micropost.created_at) %> ago.
<% if current_user?(micropost.user) %>
<%= link_to "Done", micropost_path(micropost), method: :delete, data: { confirm: "Keep up the good work!" } %>
<% end %>
</span>
</li>
routes.rb
Rails.application.routes.draw do
resources :users
resources :microposts
get '/about', to: 'static_pages#about'
get '/contact', to: 'static_pages#contact'
get '/signup', to: 'users#new'
post '/signup', to: 'users#create'
get '/login', to: 'sessions#new'
post '/login', to: 'sessions#create'
delete '/logout', to: 'sessions#destroy'
get '/users/admin', to: 'users#admin'
get 'tags/:tag', to: 'microposts#index', as: :tag
root 'static_pages#home'
end
micropost_controller
class MicropostsController < ApplicationController
before_action :logged_in_user, only: [:create, :destroy]
before_action :correct_user, only: :destroy
def index
params[:tag] ? #microposts = Micropost.tagged_with(params[:tag]) : #microposts = Micropost.all
end
def show
#micropost = Micropost.find(params[:id])
end
def create
#micropost = current_user.microposts.build(micropost_params)
if #micropost.save
flash[:success] = "Micropost created!"
redirect_to root_url
else
#feed_items = []
render 'static_pages/home'
end
end
def destroy
#micropost.destroy
flash[:success] = "You have deleted a task!"
redirect_to request.referrer || root_url
end
private
def micropost_params
params.require(:micropost).permit(:content, :tag_list, :tag,
{tag_ids: [] }, :tag_ids)
end
def correct_user
#micropost = current_user.microposts.find_by(id: params[:id])
redirect_to root_url if #micropost.nil?
end
end
Micropost model
class Micropost < ApplicationRecord
belongs_to :user
has_many :taggings
has_many :tags, through: :taggings
default_scope -> { order(created_at: :desc) }
validates :user_id, presence: true
validates :content, presence: true, length: {maximum: 140 }
attr_accessor :tag_list
def self.tagged_with(name)
Tag.find_by!(name: name).microposts
end
def self.tag_counts
Tag.select('tags.*, count(taggings.tag_id) as count')
.joins(:taggings).group('taggings.tag_id')
end
def tag_list
tags.map(&:name).join(', ')
end
def tag_list=(names)
self.tags = names.split(',').map do |n|
Tag.where(name: n.strip).first_or_create!
end
end
end
Tag model
class Tag < ApplicationRecord
attr_accessor :name
has_many :taggings
has_many :microposts, through: :taggings
end
static_pages controller
class StaticPagesController < ApplicationController
def home
if logged_in?
#micropost = current_user.microposts.build
#feed_items = current_user.feed.paginate(page: params[:page])
end
end
def help
end
def about
end
def contact
end
end
feed.html.erb
<% if #feed_items.any? %>
<ol class="microposts">
<%= render #feed_items %>
</ol>
<%= will_paginate #feed_items %>
<% end %>
I got the following error
ActionController::UrlGenerationError in StaticPages#home
No route matches {:action=>"index", :controller=>"microposts", :tag=>nil}, missing required keys: [:tag]
app/views/microposts/_micropost.html.erb:5:in `block in _app_views_microposts__micropost_html_erb___3891111682689684005_70324923859580'
app/views/microposts/_micropost.html.erb:5:in `map'
app/views/microposts/_micropost.html.erb:5:in `_app_views_microposts__micropost_html_erb___3891111682689684005_70324923859580'
app/views/shared/_feed.html.erb:3:in `_app_views_shared__feed_html_erb__3168328449514417483_70324923896060'
app/views/static_pages/home.html.erb:13:in `_app_views_static_pages_home_html_erb__3511776991923566869_70324898321240'
Can anyone suggest what might be wrong here? Please let me know if more information is needed.
Update: I have implemented some of the changes provided by the answer below, but still has not understood why :tag is not detected, and why the code in red is actually highlighted.

Answer 1

ActionController::UrlGenerationError in StaticPages#home
No route matches {:action=>"index", :controller=>"microposts", :tag=>nil}, missing required keys: [:tag]
The problem is you don't have an index route for your microposts.
Rails.application.routes.draw do
root 'static_pages#home'
get '/readme', to: 'static_pages#readme'
get '/about', to: 'static_pages#about'
get '/contact', to: 'static_pages#contact'
get '/signup', to: 'users#new'
post '/signup', to: 'users#create'
get '/login', to: 'sessions#new'
post '/login', to: 'sessions#create'
delete '/logout', to: 'sessions#destroy'
get '/users/admin', to: 'users#admin'
resources :users
resources :microposts, only: [:create, :destroy] #Here's the problem
get 'tags/:tag', to: 'microposts#index', as: :tag
end
change to:
resources :microposts, only: [:index, :create, :destroy]
EDIT:
Another problem is
if logged_in?
#micropost = current_user.microposts.build #this just returns a new 1
#feed_items = current_user.feed.paginate(page: params[:page])
end
You probably want something like:
if logged_in?
#microposts = current_user.microposts
#feed_items = Micropost.all.paginate(page: params[:page])
end
This will give you all the user's microposts. Then you iterate through them in your views.

Answer 2

I actually found the cause of the problem to be quite simple. After running rails console, it seems like my db:seed wasn't even raked properly, causing my tags to have nil names and causing me to be unable to find the route. Looking further into Rails console is adding nil instead of values to solve my seed adding problem, I realised I have added attr_accessor, forgetting that normal attributes should be added via the command line into the Migration instead of writing into the Model directly. Removing it according to the post updates my database and the code works.