link_to post ID in Rails - ruby-on-rails-3

Question

In my feed I have this:
<span class="title"><strong><%= link_to feed_item.title, #micropost %></strong></span><br>
I cannot figure out how to make it link to the individual pages for posts.
Right now it links to: http://localhost:3000/microposts and I get an error: No route matches [GET] "/microposts"
if I manually type the URL: http://localhost:3000/microposts/25 I can see the indivual page for the post.
This works fin linking to a user profile, but I can't get the link working to a micropost's page.
<%= link_to feed_item.user.name, feed_item.user %>
I'm new to rails and I'm trying to figure this out. Any help would be appreciated.
microposts_controller.rb
class MicropostsController < ApplicationController
before_filter :signed_in_user, only: [:create, :destroy]
before_filter :correct_user, only: :destroy
def index
end
def show
#micropost = Micropost.find(params[:id])
end
def create
#micropost = current_user.microposts.build(params[:micropost])
if #micropost.save
flash[:success] = "Micropost created!"
redirect_to root_url
else
#feed_items = []
render 'static_pages/home'
end
end
def destroy
#micropost.destroy
redirect_to root_url
end
private
def correct_user
#micropost = current_user.microposts.find_by_id(params[:id])
redirect_to root_url if #micropost.nil?
end
end
config/routes.rb
SampleApp::Application.routes.draw do
resources :users do
member do
get :following, :followers
end
end
resources :sessions, only: [:new, :create, :destroy]
resources :microposts, only: [:create, :destroy, :show]
resources :relationships, only: [:create, :destroy]
root to: 'static_pages#home'
match '/signup', to: 'users#new'
match '/signin', to: 'sessions#new'
match '/signout', to: 'sessions#destroy', via: :delete
match '/help', to: 'static_pages#help'
match '/about', to: 'static_pages#about'
match '/contact', to: 'static_pages#contact'
end
_feed_item.html.erb
<li id="<%= feed_item.id %>">
<%= link_to gravatar_for(feed_item.user), feed_item.user %>
<span class="title"><strong><%= link_to feed_item.title, micropost_path(#micropost) %></strong></span><br>
<span class="user">
<p><small>Created by: <%= link_to feed_item.user.name, feed_item.user %><br>
<%= feed_item.loc1T %><br>
<%= feed_item.startTime.strftime('%A, %B %d, %Y') %></small></p>
</span>
<span class="content"><%= feed_item.content %></span>
<span class="timestamp">
Posted <%= time_ago_in_words(feed_item.created_at) %> ago.
</span>
<% if current_user?(feed_item.user) %>
<%= link_to "delete", feed_item, method: :delete,
data: { confirm: "Are you sure?" },
title: feed_item.content %>
<% end %>
</li>
feed.html.erb
<% if #feed_items.any? %>
<ol class="microposts">
<%= render partial: 'shared/feed_item', collection: #feed_items %>
</ol>
<%= will_paginate #feed_items %>
<% end %>`
static_pages_controller
class StaticPagesController < ApplicationController
def home
if signed_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

Answer 1

Long answer
Rails generates a number of handy named routes for you when you add routes to your routes.rb file. Usually when in doubt for routes I take a look at my rake routes task which shows you a list of all available routes. Try running rake routes > routes.txt and open up the corresponding routes.txt file.
The resulting file will list out a series of requests for you, in your case you should see something similar to this for your microposts controller:
POST /microposts(.:format) microposts#create
micropost GET /microposts/:id(.:format) microposts#show
DELETE /microposts/:id(.:format) microposts#destroy
Rake routes produces the following information for each of your routes (where applicable):
The route name (if any)
The HTTP verb used (if the route doesn’t respond to all verbs)
The URL pattern to match
The routing parameters for the route
With that information in mind be can simply look at the urls provided in the routes.txt file for the url we're trying to get to (/microposts/25). You'll see that the listed /microposts/:id(.:format) url pattern handles that perfectly. Lo and behold it also maps to the microposts#show action that you want so now to get the named route just look at the first column to appear and you'll see the "microposts" keyword. Simply add _path` to this and you'll have your named route usable in views to generate link urls. Since this particular route requires an id parameter (as detailed in the url pattern) you have to pass the named route helper and id argument as well.
Also in your routes.rb file when you add resources :something it generates routes for each of the default seven RESTful routes (new, create, edit, update, delete, index, show). In your case you're explicitly telling rails to generate default routes for the actions create, destroy and show so you can erase the line at the bottom
match "/microposts/:id" => "microposts#show" because that's already being handled.
Short answer
Change this:
<%= link_to feed_item.title, #micropost %>
To this:
<%= link_to feed_item.title, micropost_path(feed_item) %>
See Ruby on Rails Guides: Rails routing from the Outside In for all you need to know about routes.