No route matches [POST] - Adding route does not work - ruby-on-rails

Question

My method does not work.
I have a games library, where I can add, show, edit, and destroy. I want to expand it and add one more method clone to it.
Library created with rails g scaffold:
The clone method in games_controller.rb
def clone
#game.clone
respond_to do |format|
format.html { redirect_to games_url, notice: 'Game was successfully cloned.'}
format.json { head :no_content }
end
end
The call code for Clone in index
<% #games.each do |game| %>
<tr>
<td><%= game.title %></td>
<td><%= game.description %></td>
<td><%= link_to 'Show', game %></td>
<td><%= link_to 'Edit', edit_game_path(game) %></td>
<td><%= link_to 'Destroy', game, method: :delete, data: { confirm: '.. sure?' } %></td>
<td><%= link_to 'Clone', game, method: :clone, data: { confirm: '.. sure?' } %></td>
</tr>
<% end %>
The routes code in routes.rb
resources :games do
resources :comments
post 'clone'
end
a view in games library

Answer 1

You are doing it wrong. You have method: :clone which is not valid. The valid values for method option for link_to are post, patch, put and delete.
method: symbol of HTTP verb - This modifier will dynamically create an
HTML form and immediately submit the form for processing using the
HTTP verb specified. Useful for having links perform a POST operation
in dangerous actions like deleting a record (which search bots can
follow while spidering your site). Supported verbs are :post, :delete,
:patch, and :put. Note that if the user has JavaScript disabled, the
request will fall back to using GET. If href: '#' is used and the user
has JavaScript disabled clicking the link will have no effect. If you
are relying on the POST behavior, you should check for it in your
controller's action by using the request object's methods for post?,
delete?, patch?, or put?.
Now coming to your routes, when you do rake routes, you will see the below
game_clone POST /games/:game_id/clone(.:format) games#clone
So, the link_to should look like below
<%= link_to 'Clone', game_clone_path(game), method: :post, data: { confirm: '.. sure?' } %>
Couldn't find Game without an ID
Ok, you are cloning a Game instance. Normally you look for an instance with an :id, but with your current routes, the :game_id will passed in the params which is not appropriate to want you need. You should change your routes to pass :id instead of :game_id. So the final solution will be
Final Solution:
resources :games do
resources :comments
post 'clone', on: :member
end
The above will create a path helper with the below
clone_game POST /games/:id/clone(.:format) games#clone
Now change the link_to with the new path helper and you are good to go
<%= link_to 'Clone', clone_game_path(game), method: :post, data: { confirm: '.. sure?' } %>
Note:
You should be careful when adding custom routes to your resourceful routes. This will create path helpers with unnecessary keys such as :*_id(:game_id in your case). These routes should be added as collection route or a member route depending upon the scenario. For more info refer these guides