Cannot load custom controller action from link_to - ruby-on-rails

Question

I'm a rails beginner and have been several hours now trying to figure out why my "generate new password" link, which was supposed to execute my custom update_password action inside my users controller, and then flash the password back on the screen (later i plan to send this by e-mail or sms, but for now this would do) keeps executing the create method/action...
I understand I have two POST methods for the users index screen...but cannot understand (since i even placed it first on the routes file) why create is the one that keeps getting executed. I know it doesn't go to the update method, because i filled it with debugger logging messages, which do not show up anywhere. (and the logging is active since i see the index method logging message)
Here is what I'm doing :
routes.rb file extract :
match 'users?user_id=(:user_id)', to: "users#update_password", via: :post, as: "users_update_password"
resources :users
rake routes (controller users)
users_update_password POST /users?user_id=(:user_id)(.:format) users#update_password
users GET /users(.:format) users#index
POST /users(.:format) users#create
new_user GET /users/new(.:format) users#new
edit_user GET /users/:id/edit(.:format) users#edit
user GET /users/:id(.:format) users#show
PUT /users/:id(.:format) users#update
DELETE /users/:id(.:format) users#destroy
signup /signup(.:format) users#new
users_controller.rb
def update_password
logger.info "Inside update_password"
logger.flush
password= generate_password()
logger.debug "Password is #{password}"
#user = User.find_by_id(params[:user_id])
logger.debug "user is #{#user}"
if #user.update_attributes(password:password, password_confirmation:password)
logger.info "inside the if"
flash[:notice] = "New password for user #{#user.name}: #{password}"
logger.debug "Flash is #{flash}"
redirect_to users_path
else
logger.debug "I am on else of update_password"
flash[:alert] = "Name: #{#user.name} password: #{password}"
render 'index'
end
end
def index
logger.info "Inside controller index method"
#users = User.paginate(page: params[:page])
end
_user.html.erb
<% if current_user.admin? && !current_user?(user) %>
| <%= link_to "delete", user, method: :delete, confirm: "Are you sure?" %>
| <%= link_to "Generate new password", users_update_password_path(:user_id=>user.id), method: :post, confirm: "Are you sure? This will reset current password" %>
<% end %>
Thank you for your help

Answer 1

It might simplify things if you make this a member of your resource routes?
resources :users do
member do
post 'update_password'
end
end
Then path helper probably looks like
link_to "Generate new password", update_password_user_path(user), method: :post
# POST. /users/:id/update_password
http://guides.rubyonrails.org/routing.html#adding-more-restful-actions

Answer 2

When you use HTTP POST, the data is not sent in the URL. Your route is looking for data in the URL, which is done via HTTP GET. So if you want to use a POST, make your route something like:
post "users/update_password" => "users#update_password", :as => "users_update_password"