No route matches [POST] "/users/1"

Question

I have a link_to in a view that I would like to use to call a method in my controller to update the model.

Here's the view code:

  <tbody>
    <% @users.each do |user| %>
      <tr data-user-id="<%= user.id %>">
        <td><%= user.email %></td>
        <td><%= link_to 'Show', user %></td>
        <td><%= link_to 'Edit', edit_user_path(user) %></td>
        <td><%= link_to 'Destroy', user, method: :delete, data: { confirm: 'Are you sure?' } %></td>
        <td><%= link_to 'Admin', user, method: :admin %></td>      

      </tr>
    <% end %>
  </tbody>

this link is the specific one that isnt working, since it's not a default method in the users controller

<td><%= link_to 'Admin', user, method: :admin %></td>  

The admin method in my controller looks like this

  def admin
    @user = User.find(params[:id])

    if @user.isadmin?

      redirect_to '/users', alert: 'User was updated to admin.'

      else
        redirect_to '/users', alert: 'User is already an admin.'
      end

  end

I dont have any route defined in the routes.rb file because I'm not sure how to define it correctly. Is there an issue with the view or is an issue with not having a route. I thought that i could specify the controller and action in the link but that doesnt seem to be working.

Here's the console output

Started POST "/users/5" for 192.168.1.1 at 2019-03-13 22:25:50 -0400

ActionController::RoutingError (No route matches [POST] "/users/5"):

actionpack (5.2.2) lib/action_dispatch/middleware/debug_exceptions.rb:65:in `call'
web-console (3.7.0) lib/web_console/middleware.rb:135:in `call_app'
web-console (3.7.0) lib/web_console/middleware.rb:22:in `block in call'
web-console (3.7.0) lib/web_console/middleware.rb:20:in `catch'
web-console (3.7.0) lib/web_console/middleware.rb:20:in `call'
actionpack (5.2.2) lib/action_dispatch/middleware/show_exceptions.rb:33:in `call'
railties (5.2.2) lib/rails/rack/logger.rb:38:in `call_app'
railties (5.2.2) lib/rails/rack/logger.rb:26:in `block in call'
activesupport (5.2.2) lib/active_support/tagged_logging.rb:71:in `block in tagged'
activesupport (5.2.2) lib/active_support/tagged_logging.rb:28:in `tagged'
activesupport (5.2.2) lib/active_support/tagged_logging.rb:71:in `tagged'
railties (5.2.2) lib/rails/rack/logger.rb:26:in `call'
sprockets-rails (3.2.1) lib/sprockets/rails/quiet_assets.rb:13:in `call'
actionpack (5.2.2) lib/action_dispatch/middleware/remote_ip.rb:81:in `call'
actionpack (5.2.2) lib/action_dispatch/middleware/request_id.rb:27:in `call'
rack (2.0.6) lib/rack/method_override.rb:22:in `call'
rack (2.0.6) lib/rack/runtime.rb:22:in `call'
activesupport (5.2.2) lib/active_support/cache/strategy/local_cache_middleware.rb:29:in `call'
actionpack (5.2.2) lib/action_dispatch/middleware/executor.rb:14:in `call'
actionpack (5.2.2) lib/action_dispatch/middleware/static.rb:127:in `call'
rack (2.0.6) lib/rack/sendfile.rb:111:in `call'
railties (5.2.2) lib/rails/engine.rb:524:in `call'
puma (3.12.0) lib/puma/configuration.rb:225:in `call'
puma (3.12.0) lib/puma/server.rb:658:in `handle_request'
puma (3.12.0) lib/puma/server.rb:472:in `process_client'
puma (3.12.0) lib/puma/server.rb:332:in `block in run'
puma (3.12.0) lib/puma/thread_pool.rb:133:in `block in spawn_thread'

routes.rb

  resources :users
  post 'users/:id' =>  'users#admin'

Answer 1

In view file your Admin link is incorrect. Method should be :delete, :post etc not :admin

<td><%= link_to 'Admin', user, method: :admin %></td> 

Here's the fix -

Solution #1

# In view
<td><%= link_to 'Admin', admin_user_path(user) %></td> 

Route should be

resources :users do
 member do
  get 'admin'
 end
end

Solution #2

# In view
<td><%= link_to 'Admin', admin_user_path(user), method: :post %></td> 

Route should be

resources :users do
 member do
  post 'admin'
 end
end

Answer 2

this should create the route you need.

post 'users/:id/admin' =>  'users#admin'

your link would look like

<% = link_to 'Admin', users_admin_path(user) %> # or whatever rails names your route

Answer 3

Try changing your link to:

 <%= link_to "Admin", admin_path(user) %>

And your route to:

 post 'admin', to: 'admin#users', as: :admin