I have been programming in Ruby on Rails for a while now, but never really dug deep into routing until recently. After reading a fair amount of documentation and googling, I haven't been able to answer this question.
How do you change a URL after a route is matched? To better explain this, let me set a scenario I'm trying to solve. The root of my website while testing is localhost:3000. My login page is localhost:3000/login. Once logged in though, I want the URL to read localhost:3000 again with no extension. The actual page name is dashboard and my route is as follows currently.
get 'dashboard' => 'user#dashboard'
This only matches when the URL is localhost:3000/dashboard, but I wan't to have cleaner URL like a lot of sites have. How is this achieved with Ruby On Rails? I want to avoid a javascript solutions or anything that is a workaround.
Any help or tips is greatly appreciated. Many thanks in advance.
I've provided the solution below, but I agree with max that your wanting to make a RESTful URL less meaningful is backwards. You should strive to alias a URL to make it more meaningful (e.g. from site.com/posts/34239482069472/ to site.com/posts/my-post-title).
The URL that appears in the address bar is an instruction to an app. When a user puts "site.com/dashboard" into the address bar, they're instructing the app to make an HTTP request get 'dashboard'. The Controller#action is a set of instructions the app executes when it receives that request. If you're following Rails naming convention then Users#dashboard will retrieve data and then by default render the view template at views/users/dashboard.html.erb. Understand this: you're not changing the URL for a given view, you're changing which view template is rendered by the Controller#action that is set for that url.
This means the Controller#action for your root_url (i.e. your root to: 'controller#action' in config/routes.rb) should render one view template if user is logged in and a different view template if a user is not logged in. Assuming root to: welcome#index, your controller action would look something like this:
app/controllers/welcome_controller.rb
def index
# db queries, logic, set #variables
if session[:user_id]
render "users/dashboard" # app/views/users/dashboard.html.erb
else
render "index" # app/views/welcome/index.html.erb
end
end
Note that if the view template you want to render corresponds to the controller, e.g. users_controller.rb action is rendering a view in views/users, then you only need to give the view name, otherwise you need to give a path (relative to app/views).
Why? /dashboard is a proper RESTful definition of a resource. In REST a route should have the same response independent of state. So having a radically different root page for a logged in user violates REST.
Also your users may want to access the index page as well the dashboard and you would be denying them that possibility.
These kind of URL micro-optimizations do not warrant hacking a bunch of state into your routes definitions.
I have controller ArticlesController.
I have resource articles (in routes.rb file).
Why action articles#new corresponds GET /articles/new request and action acticles#create corresponds POST /articles request. Why not POST /articles/new ?
The new action displays a view in which you have a form that you fill out and submit. In this case, its a form for articles. This form could be anywhere on your website, but Rails convention holds that it is in your new page.
The create action takes the information you submitted in the form and tries to create an object. In this case, an article. This action does not, by convention, display a view, but redirects to another page. For me, it's usually the show page of that newly created article.
It's defined in the RESTful architecture that a POST request to a collection URI (e.g. "/articles") should create a new entry.
As already noted, the "/articles/new" URI is simply displaying the form, and it's not really an element URI (in the RESTful sense). Therefore it would be inproper to POST, PUT or DELETE it.
See http://en.wikipedia.org/wiki/Representational_state_transfer
There two different routes but it calling the same controller function.
two possible routes:
1) ios-mobile-developer-india
2) salesforce-consultant-india
we are technology and location dynamically.
routes.rb:
get ':tech-mobile-developer-:loc' => application#tech_location
get ':tech-consultant-:loc' => application#tech_location
If i search ios-consultant-india, it 'll show the output. But, I want to redirect to ios-consultant-india. can anyone tell how to redirect based on technology?
Have you tried like this get '/stories', to: redirect('/articles')
routing redirect
If you want to perform a redirect at route level, you may want to use the router redirect feature.
get '/:tech-mobile-developer-:loc', to: redirect('/%{tech}-consultant-%{loc}')
In this way you don't need to inject the redirect code in the action itself, and the action will only contain the code responsible to render the action content.
I have 2 questions:
I have a controller called homepage. I have a view called samplegraph in my homepage's view directory. I want to get the routing working correctly such that www.homepage.com/samplegraph takes me to the samplegraph page.
As far as I can tell, the route for it in routes.rb should be something like this:
GET 'homepage/samplegraph' => 'homepage#showgraph1'
If I'm understanding rails routing correctly, this statement routes GET requests to homepage/samplegraph to the homepage controller's showgraph1 action. At this point I'm not particularly sure what the showgraph1 action should be in order to render the view page(samplegraph). At the moment the action is simply empty. I don't really know what to put here.
Second question:
Also, while I was researching rails routing, I was looking into resource based routing. For my purposes, I don't need most of the stuff generated by that. One thing I am interested in is that invoking resource based routing automatically generates Paths for you via helpers(I think?).
How would I generate a Path for my route, such that I'd be able to use a link_to method to link various parts of the application together? Any help/comments would be greatly appreciated.
Firstly, if you want to get 'samplegraph' page rendered by hitting 'www.homepage.com/samplegraph', you will need to update your route.
Replace
get 'homepage/samplegraph' => 'homepage#showgraph1'
with
get '/samplegraph' => 'homepage#showgraph1'
Now in showgraph1 action of your homepage controller, you will need to render samplegraph view page at last line of the action.
render 'samplegraph'
As of you second question, just hit rake routes on your terminal from your app directory. It will show all routes with helpers which you can use with link_to. You will need to append _path to those routes while using with link_to
Like #RAJ said first of all you need to change your route to
get '/samplegraph' => 'homepage#showgraph1'
At this point I'm not particularly sure what the showgraph1 action should be in order to render the view page(samplegraph)
Rails doesn't care if your action is empty or not, it'll still render your actions view even if it's empty. Since your action is named showgraph1 so it'll make rails look for showgraph1.html.erb with path views/homepage/showgraph1.html.erb
To change this behavior you need to use render 'samplegraph' in your action
One thing I am interested in is that invoking resource based routing automatically generates Paths for you via helpers(I think?)
Rails generate path and url helpers for each route and it doesn't depend on how your routes are defined but you can customize your helper methods by specifying as: option
get 'homepage/samplegraph' => 'homepage#showgraph1', as: 'showgraph'
This will make your helper methods showgraph_path and showgraph_url
I'm failing to understand the correlation between routes, controllers, and views (and how they connect to each other).
So, I've got my controller with the index,show,new,create,destroy methods. And the corresponding
GET /entries(.:format) entries#index
POST /entries(.:format) entries#create
GET /entries/new(.:format) entries#new
GET /entries/:id/edit(.:format) entries#edit
GET /entries/:id(.:format) entries#show
PUT /entries/:id(.:format) entries#update
DELETE /entries/:id(.:format) entries#destroy
How come if I add a new method vote_up or vote_down, for example, and the views with matching action names, it doesn't work.
1) What is the proper way to add new actions and connect them to views?
2) Bonus What is the proper way to make these methods ajax-compatible (render a partial with ajax)? What happens if the user doesn't have js enabled?
I may expand/evolve this question based on the answers I get.
I'm tired of googling things like custom action route rails and the like to hodge-podge my apps. It's draining and poor form and I'm finally getting to the level to comprehend the lingo--I've been self taught 100%...so please try to be understanding if you can for a young padawan.
Here's how to think of it, from the beginning:
1) The one and only thing your app does is respond to HTTP REQUESTS.
The most typical kinds of requests are:
GET - the user types something into the URL bar of their browser and hits enter.
POST - the user submits a form.
There are also other kinds of HTTP requests, most importantly PUT, PATCH and DELETE. Rails follows the REST pattern, which means it assigns specific meanings to these HTTP verbs.
2) When any request comes into your app, it has to be routed to a Controller Action.
Your routes.rb file is a set of instructions for the Rails Router (ActionDispatch) that tells the router where to send requests. The "standard" rails resource is given as a shortcut, like this:
resources :things
This means the following:
GET /things => things#index
GET /things/:id => things#show
GET /things/new => things#new
GET /things/edit/:id => things#edit
POST /things => things#create
PUT /things/:id => things#update
DELETE /things/:id => things#destroy
These are considered the standard RESTful actions - nothing else is set by your resources :things declaration. So, if you want the controller to perform other non-standard actions, you have to add them manually.
If you want to perform an action on a specific record, the best way is to use:
resources :things do
member do
get 'vote_up'
end
end
This tells the router that if someone makes a GET request to /things/123/vote_up that it should trigger the ThingsController vote_up action.
All of this is spelled out in great detail in the Rails Guide, you should read the whole thing.
3) Your controller's job is to send a response to the request.
Normally this means something like loading a record from the database and rendering the view for that record.
Each controller action ends by sending the response back to the incoming request. This response can be either a render call - which means send back some data in some format - or a redirect call - which basically makes a new request for you and therefore you get the response of that other request.
In Rails a redirect is effectively sending the request to a different controller action.
A Render call sends data as a response to the request.
When you call render :new, this is a shortcut to render :template => :new, which loads the app/views/things/new.html.erb (or whatever) template, sends it the data from the controller (normally your instance variables) and evaluates this using the template language (erb, haml, etc.) This results in a big string of HTML, which the controller then delivers to the browser.
Want to see what this for yourself? Try ending a controller with render :text => 'Hello World', or even:
render :inline => '<!DOCTYPE html><head><title>Inline Wow!</title></head><body>Mind blown.</body></html>'
See what happens.
When responding (rendering) you can send "normal" HTML templates, with a whole page worth of information in it (head, body, etc.), or a partial that is used by Ajax. You can also send raw data such as JSON or XML. It's all actually just text, and depending on the content of that text (and the HTTP headers that come with it) the browser, script, or client application handles it accordingly.
Again, see the Rails Guide.
4) When the request is made by a browser you probably want to send back HTML. If the request is made by Ajax you probably want to send back JSON.
In the case of a custom action like vote_up you might not want to show a template at all, but just redirect. So, you might have something like this:
ThingsController < ApplicationController
def vote_up
#thing = Thing.find(params[:id])
#thing.vote_up
redirect_to #thing
end
end
Now, one of the benefits of the router is it will give you URL helpers. If you've created the route and action as shown before, on your "show thing" page you could have a URL like this:
link_to 'Vote up this thing!', vote_up_thing_path(#thing)
That would create a link to things/123/vote_up, and if someone clicked on it it would run the code in the vote_up action on the ThingsController, and then redirect back to the show thing view.
5) Your templates send messages to the controllers using links and forms. Links make GET requests, forms make POST requests.
If you want to start having AJAX requests, that's fine. In that case, you just need to make the request in Javascript, and handle the response. So, for instance, you could put something like this in your template:
= link_to 'Vote up this thing', vote_up_thing_path(#thing), :id => 'vote-up-button'
Then in Javascript (with jQuery) you could have a function like this:
$(function(){
$('a#vote-up-button').click( function(event){
event.preventDefault();
$.ajax({
url: this.attr('href'),
type: 'GET',
success: function(){...},
error: function(){...}
});
});
});
In this case the jQuery Ajax method is just making a get request, and then running a callback function based on the response it got.
6) The structure of your controller/routes does not affect what kind of requests you can make, only what action will respond to what HTTP method on what URL.
What you do INSIDE your controller action determines whether you are ready to respond to javascript or html requests etc.
While rails is certainly able to handle multiple request formats in a single controller action, using the respond_to block, as a matter of practicality I find things work much more smoothly when you choose to have routes only respond to one format or another.
IE: I would make your normal page load requests (index, show, new, edit) just HTML requests, and then I would make any additional AJAX actions you want to add be Javascript only -- ie. they respond with JSON instead of HTML. You don't have to do this, of course, but your life will be easier if you do.
I hope this gives you a clearer sense of what is happening in your app. Welcome to Rails, you're joining a great community!
Welcome to the ROR world. :)
Routes, controllers, and views work together to translate a HTTP request into a response of some kind (be it HTML, JSON, or XML). Each attacks a different piece of the problem.
Starting from the end, views are the templates in the rails world and they typically are ERB. ERB is just one templating system, others can be used as well, like haml. Their job is to take some data given to them by the controller and produce formatted output, again typically HTML, JSON, or XML.
But how do you know which view to render for a particular request? How do you get data into your view so that it can do all the fancy dynamic stuff you need? This is where controllers come in. Controllers are ruby classes with the job of examining the parsed HTTP request and any related parameters, fetching data from the database (or wherever), and then passing that data to a view. A controller will typically have several different methods, each corresponding to a different task (e.g. create, show, update, etc).
Lastly, Routes are a DSL for parsing HTTP requests and dispatching a parsed HTTP request to a particular controller method. They are the glue that Rails uses to route URLs to methods, hence the name, routes.
Regarding your specific questions:
1) To create a new action, you have to add a route, a controller method, and a view. So for instance if you wanted to get a count of your entries, you could add a route like:
get '/entries/count' => "entries#count"
This tells ROR to call the count method in the entries controller when that URL is received. Your controller method in this case would be something simple like:
def count
#cnt = Entries.count
end
Then last, you'd make a view in app/views/entries/count.html.erb that had something like:
<p>Count: <%= #cnt %></p>
2) Ajax compatible code really just a way of asking "what if the requested format for this request is JSON?". For this, you'll want to use respond_to method. In a way, respond_to is a formal way of specifying a different view to handle the formatting of the request. To continue with the example above, you could do:
def count
#cnt = Entries.count
respond_to do |fmt|
fmt.html # This just renders the default template
fmt.json { render json: { count: #cnt } }
end
end
N.b. - All code above freehanded. :)
If you have the RESTful controller:
resources :entries do
collection do
get :vote_down
get :vote_up
end
end
this will generate 2 additional routes:
GET /entries/:id/vote_up(.:format) entries#vote_up
GET /entries/:id/vote_down(.:format) entries#vote_down
You can easily change HTTP method to GET, POST, PUT and DELETE.
Also, check "Adding More RESTful Actions" in the routes documentation.