I have product with a foreign collection_id key
I want to pass an id to a controller.
To do so i have the following routes for my controller :
controller :magasin do
get "magasin" => "magasin#index"
end
The only view in my controller is magasin/index.html.erb
The link to magasin is link_to collection.nom, magasin_path(collection)
This kind of syntax usually works in controllers with models. Here my link is : http://localhost:3000/magasin.2 instead of http://localhost:3000/magasin/2
Later on i will need to call the same view with product_kind_id instead of collection_id and i will add sort by name/price ....
How can i have the ID as a normal argument (/:id)instead of a type(.id)?
A popular URL schema to follow is RESTful routing. Rails has this built-in and will set it up for you if you initialize your resource via rails generate scaffold Magasin nom:string.
If you put resources :magasins in your routing file, it will route /magasins to MagasinsController#index and /magasins/1 to MagasinsController#show with params[:id] set to "1". It will also set up a few other routes that will be useful in the future but for now will just raise an action not found exception.
You don't want to use the dot as an argument delimiter, since Rails places what comes after the dot in the request.format method or just in params[:format] (ordinarily accessed through the respond_to method that comes with the generated scaffolds). Save that dot for later when you are working on delivering alternative display formats like XML and JSON.
I realize I've said a lot in a small space, so feel free to ask any follow up questions once you've consulted the Rails Guide on the issue, and I'll be very glad to help!
Related
Rails 4 - I have an action that handles routes like www.site.com/catalog/shoes/sport/ABC123 for product and www.site.com/catalog/shoes/sport for category
The problem is I have to display some seo-paid links (not my choise, I just have to) in format www.site.com/href, and that link must me handled as some product category. That's not the only case - in future, there might be some other "short"-links, that are pointing to other parts of my site
When I used Symfony, I could just write $this->forward('controller', 'action') and get another controller's output while saving short route, but in Rails I see only redirect_to, and it does not preserve short url?
Assuming I have a route get ':href' => 'index#simple', as: :simple, how do I forward execution to another controller (or just call controller's method?), preserving original route? - In "rails way", of course
Thank you
You can just use 'redirect_to controller_action_path' / redirect_to '/controller/action' from your controller action.
So, I'm implementing a pretty/SEO-friendly URL scheme for my rails app. I have a model called Artist, and I would like the Rails artist_path helper to always generate the friendly version of the path.
In my routes.rb file, I have the following line:
get 'artists/:id(/:slug)', :to => 'artists#show', :as => 'artist'
If the slug is left out, or is incorrect (it's calculated by the artist name), the controller 301 redirects to the correct URL. However, for SEO reasons, I want to ensure that all links internal to my site have the correct URL to start with.
The Artist model has the two following (very simple) functions to allow this to work:
def slug
name.parameterize
end
def to_param
"#{id}/#{slug}"
end
If I call artist_path with an artist object, this works as intended:
> app.artist_path(Artist.find 1234)
=> "/artists/1234/artist-name"
However, when I use call it with just the ID, it does not seem to use to_param at all:
> app.artist_path(id: 1234)
=> "/artists/1234"
tl;dr: How can I force Rails to always instantiate the object and call to_param on it when artist_path is called, even when only the ID is specified?
As far as I'm aware, the reason why what you're asking won't work is because when you pass in values to the built-in/automatic URL helpers (like an ID, per your example), those values just get used to "fill in the blanks" in the route URL.
If you pass an array, the values from the array will get used in order until the URL is filled in. If you pass a hash, those properties will get replaced into the URL. An object, like your model, will use it's to_param method to fill in the values... etc.
I understand your concern regarding "having knowledge of the limitations of that model," however, this behavior is standard in Rails and I don't believe it would really throw anyone. When you pass in an ID, as you do in your example, you're not telling the URL helper to "lookup a record via the model using this ID," you're simply telling it to "replace ':id' in the URL string with the ID you're providing." I'm fairly certain the built-in URL helpers wouldn't even know how to lookup the record - what model to use, etc. - other than maybe inferring from the route/controller name.
My best suggestion is to always use the instantiated model/record. If you were hoping the URL Helper would look that up for you, then there's no extra overhead as far as querying the database goes. If there's some additional reason you want to avoid instantiating the record yourself, I'd be glad to hear it and possibly provide other suggestions.
given this route
match 'posts/hello/:name/:title' => 'post#show', :as => :hello
what are the ways that I can call hello_path ?
if i call hello_path(#post), what does it try to do?
I was hoping that the :name and :title files will bind to the path automatically but it seems that rails only know how to get the :id out of the model object.
instead, it only works if I call it like
<%= link_to "link2", hello_url(:name=> #post.name, :title=>#post.title) %>
(lack of proper documentation is really killing me)
To answer your two questions:
At the command line, runrake routes to see what routes there are in
your app. It will show you all the ways you can use the named routes,
just add "_path" or "_url" to the name of the route which is shown on
the left.
Calling hello_path(#post) will generate a URL to the
show page for that hello instance.
The way you are calling it is the norm:
<%= link_to "link2", hello_url(:name=> #post.name, :title=>#post.title) %>
However, this may work too:
<%= link_to "link2", hello_url(#post.name, #post.title) %>
Here is some documentation (other than the Rails API) which should help.
http://guides.rubyonrails.org/routing.html
To answer your question of "what does hello_path try to do?"
hello_path knows how many parameters it's supposed to get. This is from counting the named parameters in config/routes. It will accept either a hash or a list of arguments. If you give it a hash, the keys must match the names of the URL parameters. If you give it a list of arguments, it'll just match them up by position - the first argument with the first named parameter.
Then, it will call to_param on each parameter individually before joining them all together (see code here, 4.0 branch).
If you pass in an object when it's expecting 2 or more params, it won't even get around to calling to_param on the object. That's when you get errors with no stack trace that say something like
No route matches {:controller=>"posts", :action=>"show", :id=>#<Post ...>}
Working with 1 named parameter
If you've only got one named parameter, things are pretty straightforward. If you need to look up your posts by name instead of id, you can just redefine to_param
class Post < ActiveRecord::Base
...
def to_param
name
end
end
Working with multiple named parameters
But if the URL has more than one named parameter in it, then redefining to_param isn't enough. Let's say you tried this:
# app/models/post.rb
class Post < ActiveRecord::Base
...
def to_param
{name: name, title: title}
end
end
# app/views/posts/index.html.erb
<%= post_path(post) %>
In this case, you'll get a routing error because you're not passing in enough arguments to post_path (see above). To get around this, I just call to_param explicitly:
# app/views/posts/index.html.erb
<%= post_path(post.to_param) %>
This is a little less slick than most Rails routing magic, but works perfectly well. If you later change the way you're looking up Posts, all you have to do is redefine to_param. No need to worry about all the places you've called post_path
Under the hood
The relevant code to look at is actionpack/lib/action_dispatch/routing
The other answers (at the time of this writing) are fine, but your reply to GregT's answer shows a lack of understand about Rails, which is fine -- we've all been there.
Specifically, three of the key principles behind Rails: convention over configuration, the model-view-controller architecture (MVC), and REST. It's stuff at the beginning of every beginning Rails book. Beginners often think they can just jump to the first chapter with code, but Rails differs from many other topics in that the first chapters explain important concepts and aren't just intro chapter filler. Because Rails isn't "code", it's a "framework of code".
"Convention over configuration" means if you follow certain conventions then you benefit from behaviors baked into Rails. Routing is one of those areas, if not the biggest, where convention benefits the developer although it is entirely configurable.
Paths following a specific routing format, are parsed into the controller, action and possibly an id, format, and additional parameters. By default and at minimum, a Rails (and also a Sinatra) path takes the following format and order:
/controller_name/action_name
It's a little more complicated than that, with more options, and it looks more like this in actuality:
/controller_name/action_name/(id)(.format)(?param=value)(&...)
...but it's more detail than is necessary for this answer.
The controller is the C in MVC, or the class that handles the request. The action is one of the seven RESTful actions (index, show, new, create, edit, update, and destroy) within that controller. Not all actions require an id (index, new and create) and not all of them are get requests (requests that generate a view, for instance destroy, create and update don't have views).
Putting it all together we see this example:
/articles/edit/1
...will route the request to the 'edit' action in the ArticlesController controller passing along id 1. It's expected that the controller will do some housekeeping, like authentication and authorization, then retrieve Article model (MCV) with ID 1 and pass it along to the "edit" view (MCV).
It's best, especially for new Rails developers, to stick to these conventions and perhaps add a few additional actions beyond those provided by REST.
You can step outside this convention by configuring in your routes.rb file an alternative routing scheme, not following REST, etc., but you'll be like a salmon swimming upstream -- it's a lot harder than going with the flow. If you go down that path (pun) you'll make a lot of additional work for yourself, probably reinvent the wheel somewhat, and lose advantages provided by the Rails framework. If you find yourself in that situation for whatever reason, perhaps Rails isn't the right tool for your job.
You can also call it like this
hello_path(#post.name, #post.title)
Hope it helps.
Im trying to get my head around the sequence of events that happen between when rails receives a get/post command and the page is served. I was just trying to map out the sequence myself and i realised i dont fully understand myself which scripts is even ran first so I'd like to clear it up in my head.
many thanks
jon
The request goes into the route matcher which parses the URL, parses the config/routes.rb and if the URL matches a route, it looks for a controller file whose name matches the controller part of the URL, (e.g. http://localhost/categories will look for a CategoriesController)
Then, one of two things happen:
If you're using a Rails restful route, the route matcher applies heuristics to figure out which of the 7 actions to call: a GET on a plural last part is mapped to index; a GET mapped to an ID-looking part after the plural is mapped to show (e.g. categories/1 or categories/something or categories/1-something); a POST to a plural last part is mapped to create; a PUT to an ID-looking part after the plural is mapped to update; a DELETE to the same URL is mapped to destroy; new and edit are mapped to GETs for categories/new & categories/edit.
If you have a custom action, you must have a method in your controller object of the same name.
The chosen action is executed and then Rails either renders the template/file/action specified in the render call within the action or it looks for a view file of the same name as the action and that ends with .html.erb (by default) in the app/views/ directory.
Simple.
Rails does quite a lot of things, a good way to get a decent overview is to read the "Action Controller Overview" document at rails guides: http://guides.rubyonrails.org/action_controller_overview.html
The basic structure is:
rack middleware
routing
filters
controller code
rendering
filters
But rails also does many things by itself to the request. It automatically determines what kind of response you want based on your accept headers, and/or if you manually specify which type of response you want with a file ending like /blog/1.xml. Rails also magically creates a nicely formatted params hash, parsing params like user[name]=foo to {:user => {:name => "foo"}}. Rails also has built-in exception handling and some nice stuff to prevent cross site request forgery and much more, so check out the Controller Overview for the lowdown on that.
My application is in RoR
I have an action/view called showsummary where the ID has been passed into the URL, and the controller has used that to instantiate #vendor where #vendor.name is the name of a company.
I would like the URL to be, rather than showsummary/1/ to have /vendor-name in the URL instead.
How do I do that?
All of these solutions use find_by_name, which would definitely require having an index on that column and require they are unique. A better solution that we have used, sacrificing a small amount of beauty, is to use prefix the vendor name with its ID. This means that you dont have to have an index on your name column and/or require uniqueness.
vendor.rb
def to_param
normalized_name = name.gsub(' ', '-').gsub(/[^a-zA-Z0-9\_\-\.]/, '')
"#{self.id}-#{normalized_name}"
end
So this would give you URLs like
/1-Acme
/19-Safeway
etc
Then in your show action you can still use
Vendor.find(params[:id])
as that method will implicitly call .to_i on its argument, and calling to_i on such a string will always return the numerical prefix and drop the remaining text- its all fluff at that point.
The above assumes you are using the default route of /:controller/:action/:id, which would make your URLs look like
/vendors/show/1-Acme
But if you want them to just look
/1-Acme
Then have a route like
map.show_vendor '/:id', :controller => 'vendors', :action => 'show'
This would imply that that it would pretty much swallow alot of URLs that you probably wouldnt want it too. Take warning.
I thought I'd mention String#parameterize, as a supplement to the tagged answer.
def to_param
"#{id}-#{name.parameterize}"
end
It'll filter out hyphenated characters, replace spaces with dashes etc.
Ryan Bates has a great screencast on this very subject.
Basically you overload the to_param method in the Vendor model.
def to_param
permalink
end
Then when you look up the resource in your controller you do something like this:
#vender = Vender.find_by_name(params[:id])
But the problem with this is that you'll have to make sure that the vendors' names are unique. If they can't be then do the other solution that Ryan suggests where he prepends the the id to the name and then parses the resulting uri to find the item id.
You do this by modifying the routes that are used to access those URL's and changing them to use :name, rather than :id. This will probably mean that you have to write the routes yourself rather than relying on resources.
For instance add this to the routes.rb file:
map.with_options :controller => "vendor" do |vendor|
vendor.connect "/vendor/:name", :action => "show"
# more routes here for update, delete, new, etc as required
end
The other change that will be required is that now you'll have to find the vendor object in the database by the name not the id, so:
#vendor = Vendor.find_by_name(params[:name])
Internally (at least to my knowledge/experimentation) whatever parameter name is not specified in the URL part of the route (i.e. not within the "/Controller/Action/:id" part of it) is tacked on to the end as a parameter.
Friendly ID
http://github.com/norman/friendly_id/blob/26b373414eba639a773e61ac595bb9c1424f6c0b/README.rdoc
I'd have to experiment a bit to get it right, but there's two primary parts to the solution.
1) Add a route.
in config/routes, add a line that sends requests of the form baseurl/controller/:vendor-name to the action showsummary, (or maybe a new action, show_summary_by_vendor_name)
[also, if you planned on using baseurl/:vendorname, that's fine too]
For convenience, make sure the parameter is something like :vendor-name, not the default :id
2) Write the controller action.
In the controller file, either edit your showsummary action to differentiate based on whether it's called with an id or with a vendorname, or just write a show_summary_by_vendor_name. (depending on best practices, and what route you wrote in 1. I don't know off the top of my head which is preferable)
You can then do
#vendor = Vendors.find_by_name(params[:vendor_name])
or something like that, and then render it the way you would in regular showsummary.
3) Use that as the link.
Once you confirm that baseurl[/controller?]/vendor-name works, and shows the summary, make sure all the links in your application, and elsewhere, use that link. Off the top of my head, I can't remember how difficult it is to integrate a custom route into link_to, but I think it's doable. Most search engines [google] rely heavily on links, so good SEO will have you using those named links, not the numbered ones. I think. I don't know much about SEO.
Take a look also at this quck start to SEO for Rails