how to set route in ruby on rails -

i redirecting city page as: <%= link_to @city.name, city_path(id: @city) %>

it's not right way since url being: localhost:3000/city?id=2
need url like: localhost:3000/newyork
did: <%= link_to @city.name, city_path(@city.name) %>
url is: http://localhost:3000/city.newyork
action city. url like:
localhost:3000/cityname
example:
localhost:3000/china
localhost:3000/pakistan

in gem file write

 gem "friendly_id" 

after writing gem in gemfile run bundle install

create migration add slugs column in model

 rails g migration addslugtocity   add_column :cities, :slug, :string  add_index :cities, :slug, unique: true 

in controller write

  @city = city.friendly.find(params[:id]) 

in city module use friendly id

class city < activerecord::base   extend friendlyid   friendly_id :title, use: :slugged end