I am rookie in rails restful web service and i am trying build service that returns a json dump of deals.So far my app returns these deals in json format when you hit http://localhost:3000/api/deals. Now i want to add two mandatory parameters(deal_id and title) and two optional parameters in the uri http://localhost:3000/api/deals?deal_id=2&title=book. What is the best way to validate these two mandatory parameters?In other words I just want to do the query only if deal_id and title parameters are present. Assuming Deal model has fields deal_id, title, description and vendor.
Here is my code
Controller
module Api
class DealsController < ApplicationController
respond_to :json
def index
#deals = Deal.all
respond_with (#deals)
end
end
end
routes
namespace :api,:defaults => {format:'json'} do
resources :deals
end
To validate presence of query parameters in a Rails route, you can use the :constraints option. So, in your case, if you want to require the presence of parameters deal_id and title, you can do so by changing:
resources :deals
To:
resources :deals, :constraints => lambda{ |req| !req.params[:deal_id].blank? && !req.params[:title].blank? }
Then, in your controller, you can access all four parameters in the params hash.
Alternatively, if you want to provide more user friendly error messages, you can do validation in the controller. There are a number of approaches. I would probably do something like this:
def action
if params[:deal_id].blank? || params[:title].blank?
flash[:warning] = 'Deal ID and title must be present'
redirect_to root_path and return
end
#rest of your code goes here
end
Related
could one advise me how to get a url like this in rails
http://www.example.com/users/5/ian
i tried the below but unsure:
route file:
devise_for :users
resources :users do
resources :socials
end
get '/users/:id/:firstname', controller: 'users', action: 'show'
users_controller.rb
def show
#user = User.find(params[:id], params[:firstname])
end
If you are trying to achieve 'friendly urls' then I suggest using this:
You don't have to create a special route:
get '/users/:id', controller: 'users', action: 'show'
Instead you have your model overwrite the to_param method:
class User
...
def to_param
"#{id}-#{firstname.try(:parameterize)}"
end
...
end
The url helper calls to_param to build the urls. If you overwrite it this way, you will receive a url like this:
http://localhost:3000/users/1-artloe
The rails find method calls .to_i on the params[:id] which, thankfully, interprets strings as number until it arrives at a character that can't become a number.
Examples:
'123abcde'.to_i # 123
'123-asdf'.to_i # 123
'asdf-123'.to_i # 0
So except for overwriting to_param, you don't have to do anything.
Try replacing this
def show
#user = User.find_by_id_and_firstname(params[:id], params[:firstname])
end
If what you are trying accomplish is "friendly urls" you would do it by:
# GET /users/1
# GET /users/joe
def show
#user = User.find_by!('id = :x OR firstname = :x', x: params[:id])
end
However you must ensure that property you are using in URLs is URL safe and unique. Usually a separate username or slug field is used.
Nothing special is needed in terms of routes.
These gems provide "friendly urls":
stringex
friendly_id
I have a model called studies.
After action redirect redirect_to edit_study_path(#new_study),
URL: http://localhost:3000/studies/2/edit.
Is there anyway to customize an url after passing id ?
For example, http://localhost:3000/study
(still going to the edit path, and still with the :id in the params)
I guess what you want is to edit the current study?
In this case, it's possible, using ressource instead of ressources in the routes.
Let's have an example:
#in routes.rb
resources :studies
resource :study
Both of them will by default link to the StudiesController and call the same actions (eg. edit in your case) but in two different routes
get "/studies/:id/edit" => "studies#edit"
get "/study/edit" => "studies#edit"
in your edit action, you should then setup to handle correctly the parameters:
def edit
#study = params[:id].nil? ? current_study : Study.find(params[:id])
end
Note you need a current_study method somewhere, and store the current_study in cookies/sessions to make it works.
Example:
# In application_controller.rb
def current_study
#current_study ||= Study.find_by(id: session[:current_study_id]) #using find_by doesn't raise exception if doesn't exists
end
def current_study= x
#current_study = x
session[:current_study_id] = x.id
end
#... And back to study controller
def create
#...
#Eg. setup current_study and go to edit after creation
if study.save
self.current_study = study
redirect_to study_edit_path #easy peesy
end
end
Happy coding,
Yacine.
I have three roles: Instuctor, Student, Admin and each have controllers with a "home" view.
so this works fine,
get "instructor/home", :to => "instructor#home"
get "student/home", :to => "student#home"
get "admin/home", :to => "admin#home"
I want to write a vanity url like below which will route based on the role of the user_id to the correct home page.
get "/:user_id/home", :to => "instructor#home" or "student#home" or "admin#home"
How do I accomplish this?
I'm providing an alternate approach as this SO question comes up near the top when searching for role based routing in Rails.
I recently needed to implement something similar but wanted to avoid having a large number of conditionals in the controller - this was compounded by the fact that each of my user roles required completely different data to be loaded and presented. I opted to move the deciding logic to the routing layer by using a Routing Constraint.
# app/constraints/role_route_constraint.rb
class RoleRouteConstraint
def initialize(&block)
#block = block || lambda { |user| true }
end
def matches?(request)
user = current_user(request)
user.present? && #block.call(user)
end
def current_user(request)
User.find_by_id(request.session[:user_id])
end
end
The most important part of the above code is the matches? method which will determine whether or not the route will match. The method is passed the request object which contains various information about the request being made. In my case, I'm looking up the :user_id stored in the session cookie and using that to find the user making the request.
You can then use this constraint when defining your routes.
# config/routes.rb
Rails.application.routes.draw do
get 'home', to: 'administrators#home', constraints: RoleRouteConstraint.new { |user| user.admin? }
get 'home', to: 'instructors#home', constraints: RoleRouteConstraint.new { |user| user.instructor? }
get 'home', to: 'students#home', constraints: RoleRouteConstraint.new { |user| user.student? }
end
With the above in place, an administrator making a request to /home would be routed the home action of the AdministratorsController, an instructor making a request to /home would be routed to the home action of the InstructorsController, and a student making a request to /home would be routed to the home action of the StudentsController.
More Information
If you're looking for more information, I recently wrote about this approach on my blog.
You can't do this with routes because the routing system does not have the information required to make this decision. All Rails knows at this point of the request is what the parameters are and does not have access to anything in the database.
What you need is a controller method that can load whatever data is required, presumably the user record, and redirects accordingly using redirect_to.
This is a fairly standard thing to do.
Update:
To perform all of this within a single controller action you will need to split up your logic according to role. An example is:
class HomeController < ApplicationController
def home
case
when #user.student?
student_home
when #user.admin?
admin_home
when #user.instructor
instructor_home
else
# Unknown user type? Render error or use a default.
end
end
protected
def instructor_home
# ...
render(:template => 'instructor_home')
end
def student_home
# ...
render(:template => 'student_home')
end
def admin_home
# ...
render(:template => 'admin_home')
end
end
I am developing a app in ruby on rails for a local business. The pages are 'static', but changeable through a backend CMS I am building for them. Is there a best practice to creating a controller for static pages? Right now I have a sites controller with all static routes, like this.
routes.rb
get "site/home"
get "site/about_us"
get "site/faq"
get "site/discounts"
get "site/services"
get "site/contact_us"
get "site/admin"
get "site/posts"
or would I be better off creating member routes for the site controller like this without the crud, because a 'Site' will not need to have the CRUD.
resources :sites, :except => [:index, :new, :create, :update, :destroy]
member do
get :home
get :about_us
get :faq
get :discounts
get :services
get :contact_us
get :admin
get :posts
end
Or is there a best practice / better way? Any answers would be appreciated. Thanks
If the static pages list are not going to increase, then you can keep the list, but if you want a dynamic list like site/any_new_url , save the routes as
get 'site/:cms_page' => 'cms#show' # all requests matching site/any_page will go CmsController, show method
This will help reduce keep the routes from bloating, but the downside is you do not know what all routes are the valid ones. Your sample code can be
def show
#page_data = Page.find_by_page(:params[:cms_page])
end
show.html.erb
<%= #page_data.html_safe %>
Dunno yet if I consider this a best practice or an abomination but here is what I came up with when tackling the same problem.
My reasoning is that the site was providing some specified functionality (which doesn't really matter for this discussion) + a bunch of information about the organisation itself (about us, contact, FAQ, homepage blurb, whatever). Since all that data was really related to the organisation, an Organisation model seemed reasonable with each of those things as attributes. Here is the model:
class Organisation < ActiveRecord::Base
...validations stuff...
def self.attrs_regex
Regexp.new(self.attrs.join("|"))
end
def self.attrs
self.column_names.reject{|name| name =~ /id|created_at|updated_at/}
end
end
Then I use the attrs class method to generate routes based on the columns. This is in my routes.rb:
Organisation.attrs.each do |attr|
get "#{attr}" => "organisation##{attr}", :as => attr.to_sym
get "#{attr}/edit" => "organisation#edit", :as => "#{attr}_edit".to_sym, :defaults => { :attribute => attr }
post "#{attr}" => "organisation#update", :as => :organisation_update, :defaults => { :attribute => attr}, :constraints => Organisation.attrs_regex
end
The controller gets a little weird and I am not thrilled with the code here but here it is anyway. I need to make sure the attribute is set and available to the views so I can do the right thing there so I set it in the application controller:
class ApplicationController < ActionController::Base
protect_from_forgery
before_filter :set_attribute
def set_attribute
#attribute = action_name.parameterize
end
end
For the organisation controller I just set the #organisation variable to be the first and only row in the database in the before_filter and then let Rails do its usual magic of calling the method, failing, and rendering a view of the same name. The edit action just uses one view file to edit all the different attributes:
class OrganisationController < ApplicationController
before_filter :set_organisation
def edit
authorize! :edit, #organisation
#attribute = params[:attribute].parameterize
end
def update
authorize! :update, #organisation
#attribute = params[:attribute]
respond_to do |format|
if #organisation.update_attributes(params[:organisation])
format.html do
redirect_to "/#{#attribute}", notice: t('successful_update')
end
format.json { head :ok }
else
format.html { render action: "edit" }
end
end
end
private
def set_organisation
#organisation = Organisation.first
end
end
So that is where I ended up. Like you I hit up SO to tap into the seething mass of genius here but ended up with disappointing results. If there is something better out there I am still hoping to find it.
What I like about what I did is that routes are automatically generated based on the structure of the organisation table.
What I don't like about what I did is that routes automatically generated based on the structure of the organisation table.
I know I will pay for that design decision when I have to deal with i18n routing and there are probably a thousand other reasons that this is a bad idea that I have yet to discover but for the moment I have a happy client.
In the end this is not a suggestion that you should do this, but I am hoping to give you more than I got so you can advance your thinking on this and hopefully end up a little closer to that best practice.
If you are going to construct a CMS, which likely connects to a database, and allow your customer to change the text on the pages of their site, I would not recommend using static pages. In Rails terms, a static page would refer to creating html files in your /views/pages directory. If you go this route, then you're walking outside of the way that Rails was designed.
I believe that what you want to do is create tables in the database that correspond to and store the data for your posts, etc. You can pull information into the controller from the model that it corresponds to and then user a view to display the data. You can create a layout for these pages and then create controllers for each of the pages that you add.
As far as routes, I would recommend using the following:
map.resource :controller_name
you then would add the code that displays the information from the CMS in the corresponding show controller action and view for each page.
I am running Ruby on Rails 3 and I would like to set up my routes to show additional information in the URL using namespaces.
In the routes.rb file I have:
namespace "users" do
resources :account
end
So, the URL to show an account page is:
http://<site_name>/users/accounts/1
I would like to rewrite/redirect that URL as/to
http://<site_name>/user/1/Test_Username
where "Test_username" is the username of the user. Also, I would like to redirect all URLs like
# "Not_real_Test_username" is a bad entered username of the user.
http://<site_name>/users/accounts/1/Not_real_Test_username
to the above.
At this time I solved part of my issuelike this:
scope :module => "users" do
match 'user/:id' => "accounts#show"
end
My apologies for not answering your question (#zetetic has done that well enough), but the best practice here is to stay within the RESTful-style Rails URL scheme except for rare exceptions. The way most people make pretty URLs in this way is to use a hyphen, e.g.:
/accounts/1-username
This does not require any routing changes. Simply implement:
class Account < ActiveRecord::Base
def to_param
"#{self.id}-#{self.username}"
end
end
And handle the extra string data in your finds by calling to_i.
class AccountController < ApplicationController
def show
#account = Account.find(params[:id].to_i)
end
end
When you do link_to 'Your Account', account_path(#account), Rails will automatically produce the pretty URL.
It's probably best to do this in the controller, since you need to retrieve the account to get the username:
#account = Account.find(params[:id])
if #account && #account.username
redirect_to("/user/#{#account.id}/#{#account.username}")
return
end
As to the second issue, you can capture the remaining parameter by defining it in the route:
get "/users/accounts/:id(/:other)" => "users/accounts#show"
This maps like so:
/users/accounts/1/something # => {:id => "1", :other => "something"}
/users/accounts/1 # => {:id => "1"}
And you can simply ignore the :other key in the controller.