I have made a resource.
resources :dashboards
I have a partial file which contains a form and I want to use this partial (as the form elements won't change) to update and create. So here is what I have:
Controller
class DashboardsController < ApplicationController
def new
#dashboard = Dashboard.new
end
end
View
/dashboards/new.html.erb
<%= render :partial => "form", :locals => { :dashboard => #dashboard } %>
Partial Form
/dashboards/_form.html.erb
<%= form_for(#dashboard) do |form| %>
.....
<% end %>
Ruby Guide
The Ruby Guide states:
The Article model is directly available to users of the application, so — following the best practices for developing with Rails — you should declare it a resource. When dealing with RESTful resources, calls to form_for can get significantly easier if you rely on record identification. In short, you can just pass the model instance and have Rails figure out model name and the rest. For example:
## Creating a new article
# long-style:
form_for(#article, :url => articles_path)
# same thing, short-style (record identification gets used):
form_for(#article)
## Editing an existing article
# long-style:
form_for(#article, :url => article_path(#article), :html => { :method => "put" })
# short-style:
form_for(#article)
Result
I thought I have followed the Rails Guide correctly. Because I made #dashboard a resource. I could just pass it into the form and have it handle the action, method and the rest. Instead I'm getting this:
<form accept-charset="UTF-8" action="/dashboards" class="new_dashboard" id="new_dashboard_" method="post">
According to the docs. Shouldn't the action of my form now be "/dashboards/new" because we are on the new action? And should it be passing an extra field declaring the method to be put when I use the same code in the /edit action??
My result is always the same no matter what. The form never changes.
What am I doing wrong?
EDIT
Here is my router info from rake routes
GET /dashboards(.:format) dashboards#index
POST /dashboards(.:format) dashboards#create
GET /dashboards/new(.:format) dashboards#new
GET /dashboards/:id/edit(.:format) dashboards#edit
GET /dashboards/:id(.:format) dashboards#show
PUT /dashboards/:id(.:format) dashboards#update
DELETE /dashboards/:id(.:format) dashboards#destroy
You are correct that you should be able to "pass #dashboard into the form and have it handle the action, method and the rest." The issue here is what new is in the context of RESTful actions.
When you declare a set of resources with resources :dashboards, you are creating a set of routes which map requests to controller actions:
GET /dashboards index
GET /dashboards/new new
POST /dashboards create
GET /dashboards/:id show
GET /dashboards/:id/edit edit
PUT /dashboards/:id update
DELETE /dashboards/:id destroy
You can check this if you run rake routes.
The issue here is that the new action is defined as a GET request to the path /dashboards/new, i.e. this is the route for the form itself. The URL in the action attribute of the actual form is something else: this is where the form will post the data to with a POST request, which on the server (rails) side will map to the create controller action.
When you use the form helper with form_for(dashboard), a form is created with a route corresponding to what dashboard is: if it is a new record (i.e. it does not yet exist in the database), then the form action will be create (and point to /dashboards), whereas if it already exists it will point to the actual URL for the record (e.g. /dashboards/123). This is what makes the form helpers so useful.
So, to sum up, /dashboards is the correct URL, not for the new action but for the create action, which the form helper uses because dashboard is a new record. new is the route to the page where the form resides, i.e. /dashboards/new.
Hope that makes sense.
p.s. as a side note, you shouldn't be accessing #dashboard in the partial if you are passing it in as a local (:locals => { :dashboard => #dashboard }). Just use dashboard.
Related
In my rails application I've created a business daily report. There is some non-trivial logic for showing it (all kind of customizable parameters that are used for filtering in the model, a controller that calls that model and some non-trivial view for it, for example, some of the columns are row-spanning over several rows).
Now I wish to send this report nightly (with fixed parameters), in addition to the user ability to generate a customize report in my web site. Of course, I wish not to re-write/duplicate my work, including the view.
My question is how can I call the controller action from my mailer so that it will be as if the page was requested by a user (without sending a get request as a browser, which I wish to avoid, of course)?
In answer to your question is if you are generating some sort of pdf report then go with using the wicke_pdf gem does exactly that generates pdfs. To send a report on a nightly basis the best thing for this is to implement some sort of cron job that runs at a particular time which you can do using the whenever gem. You can do something like:
schedule.rb
every :day, :at => '12:00am'
runner User.send_report
end
With this at hand you can see that you call the send_report method sits inside the User model class as shown below:
User.rb
class User < ActiveRecord::Base
def self.send_report
ReportMailer.report_pdf(#user).deliver
end
end
Inside send_report we call the mailer being ReportMailer which is the name of the class for our mailer and the method being report_pdf and pass in the user. BUT remember this is an example I have here I am not sure the exact specified information you want in a report.
Mailer
class ReportMailer< ActionMailer::Base
default :from => DEFAULT_FROM
def report_pdf(user)
#user = user
mail(:subject => "Overtime", :to => user.email) do |format|
format.text # renders report.text.erb for body of email
format.pdf do
attachments["report.pdf"] = WickedPdf.new.pdf_from_string(
render_to_string(:pdf => "report",:template => 'report/index.pdf.erb',
:layouts => "pdf.html"))
end
end
end
end
Inside the mailer there are a variety of things going on but the most important part is inside the format.pdf block that uses a variety of wicked_pdf methods (this is assuming that you are using wicked_pdf btw. Inside the block you create a new WickedPDF pdf object and render it to a string. Then provide it with the name of the report, the template and the layout. It is important that you create a template. This usually will where the report will be displaying from. The file type is a .pdf.erb this means that when this view or report is generated in the view the embedded ruby tags are being parsed in and the output is going to be a pdf format.
UserController
def report
#user = User.scoped
if params[:format] == 'pdf'
#Do some stuff here
User.send_report(#users)
end
respond_to do |format|
format.html
format.pdf do
render :pdf => "#{Date.today.strftime('%B')} Report",
:header => {:html => {:template => 'layouts/pdf.html.erb'}}
end
end
end
The key thing you asked that I picked up on.
how can I call the controller action from my mailer
In the controller simply collate a scope of Users, then check the format is a pdf, providing it is do some stuff. Then it will run the method send_report which I earlier highlighted in the user model class (Btw in your words this is the controller calling the model). Then inside the respond block for this there is a format.pdf so that you can generate the pdf. Once again note that you need a template for the core design of the pdf, which is similar to how rails generates an application.html.erb in the layouts. However here we have a pdf.html.erb defined. So that this can be called anywhere again in your application should you want to generate another pdf in your application somewhere else.
Think I've provided a substantial amount of information to set you off in the right direction.
My main difficulty comes from understanding the relationship that the _follow and _unfollow partials have with the create and destroy methods defined in the RelationshipsController from Chapter 11.2.3. I'll just focus on the act of unfollowing a user for now (since the act of following is mostly analogous).
Hartl defines the partial for unfollow as such:
<%= form_for(current_user.relationships.find_by_followed_id(#user), html: { method: :delete }) do |f| %>
<%= f.submit "Unfollow", class: "btn btn-large" %>
<% end %>
and the corresponding destroy action as such:
def destroy
#user = Relationship.find(params[:id]).followed
current_user.unfollow!(#user)
redirect_to #user
end
What I am having trouble understanding is:
The #user variable in the first line of the unfollow partial .. is this a) defined in the show action that currently displays the page, or b) defined in the destroy action? It appears that the form_for helper already finds the #user to be destroyed, so why does the destroy action needs to find the #user all over again to be destroyed in the controller?
In the destroy method, the #user is found by first finding the Relationship id. I don't see how the Relationship id is passed into the URI in the first place (since seeing a particular user to unfollow shows up as /users/2), much less how it is used to find the #user to destroy. I understand that each Relationship table has an id, a followed_id, and a follower_id, but do not see how the id element itself comes into play here.
Thanks, for reading, and for answering my questions!!
1.) If the partial is rendered within the show action, the variable #user must be defined in that action. Rails won't execute the destroy method so the variable definition in there will never be executed.
Since HTTP is a stateless protocol, the server needs to create the necessary state on every request. That's why #user must be defined in every action.
2.) Where did you check that the url is "/users/2"? As I don't see the whole code I can only make guesses but the following line current_user.relationships.find_by_followed_id(#user) should return a Relationship object. It will be translated into something like "/relationships/8", where 8 is the ID of the Relationship. Because you specify `method: :delete, the destroy action will be invoked.
I think the url "/users/2" is after the destroy action performed the deletion was performed. There could be a redirect in the destroy action. (eg. redirect_to current_user). You can see all the invoked actions in the log file. Try scrolling through the log and see if you can find RelationshipsController#destroy. You will see the invoked url there. Also you could inspect the HTML to see where the <form> tag's "action" attribute points to.
I'm giving up my search, I normally try to figure these things out on my own but I'm struggling hard and I just want this to work
I have the link_to seen below where #puser is the user of the profile I'm currently viewing.
<%= link_to 'Request', new_or_edit_relationship_path(nil), :remote => true, :locals => { :puser => #puser} %>
This in turn calls new_relationship_path which is a .js.erb file seen below
alert("<%= escape_javascript(puser.id) %>")
Why won't this work!? It's saying the puser variable or method is undefined. This works perfect if I was to just render a partial passing in the locals but no. Javascript doesn't want to play nice
Could anyone help explain why me or the program is stupid?
When you do a link_to as remote, the user is starting an entirely new request when they click the link. So passing a local means nothing to the new request. (The local doesn't exist any more on the new request.)
So in order for the #puser to exist on the new request, you need to pass the id for that #puser via the URL (whatever you have going on for new_or_edit_relationship_path). The new request needs to look up the puser by that id, and then it can use it in the JS alert().
Hope that helps and is a little clearer than mud.
I am working on a Rails app, and I am looking for a way to route to different actions in the controller based on the existence of parameters in the url.
For example I want website.com/model to route to model#index, however I want website.com/model?opt=dev to route to model#show. Is there some way this can be done?
Use route constraints to look at the request object and see if it has URL parameters. If you're using restful routes, you want to put this "one-off" before the restful route. Something like this:
get 'users' => 'users#show', constraints: { query_string: /.+/ }
resources :users
So what this is saying is that if you request "/users?opt=dev" then it will match your special case. Otherwise, it falls through to your normal restful route to the index action. Your model#show action will then have to know to pick up the param[:opt] and do whatever with it.
Also, note that the regex is very loose and it's simply checking for ANY param...you'll want to tighten that up to fit whatever you're trying to do.
Not strictly the same, but if you came to this post and were wondering how to do the same via a POST, then you can do it based on the request_paramters.
for your routes.rb ..
module MyConstraintName
extend self
def matches?(request)
request.request_parameters["routeFlag"] == "routeToModelShow"
end
end
match "pages/:id", :via=>:post, :controller=>"model", :action=>"show", :constraints => MyConstraintName
and in your form for example..
<%= hidden_field_tag :routeFlag, "routeToModelShow" %>
For certain models, I wish to provide functionality that allows a user to create a new record with default attributes based on copy of an existing record.
I'm wondering what would be the correct restful route for this.
My initial thinking is that it could be a parameter to the new action. I.e. to borrow from the the Rails Guides examples, instead of just:
GET : /photos/new
Also allow:
GET : /photos/new/:id
...where :id is the id of the record to use as a template. The response would be a new/edit form, same as with a plain old new but the values would be pre-filled with data from the existing record. The parameter (or absense of it) could be easily handled by the new controller method.
The alternative seems to be to create a new controller method, for example copy which would also accept an id of an existing record and response with the new form as above. This seems a little 'incorrect' to me, as the record is not actually being copied until the user saves the new record (after probably editig it somewhat).
TIA...
UPDATE: my question is not "how do I do this in rails?", it's "is it RESTful?"
my question is not "how do I do this in rails?", it's "is it RESTful?"
No, it isn't. For that matter, neither is GET /photos/new. Rails seems to be hopelessly mired in the past, where it was considered haute programme for a GET on a URI to return an HTML form which would then POST x-www-form-urlencoded data back to that same URI. The opacity of that POST forces them to invent new verbs-as-URI's like /photos/new, when you could be using PUT instead, or at least POST with the same media type.
The simplest way to make a copy of an HTTP resource RESTfully is:
GET /photos/{id}/ -> [representation of a photo resource]
...make modifications to that representation as desired...
POST /photos/ <- [modified representation]
If you're implementing this for browsers, you should be able to perform those actions via Ajax quite easily, using an HTML page sitting perhaps at /photos/manager.html/ to drive the interaction with the user.
You can try to use nested resources. I'm not exactly sure about structure of you application, but in general using nested photos will look somehow like this:
routes.rb
resources :photos do
resources :photos
end
photos_controller.rb
before_filter :find_parent_photo, :only => [:new, :create]
def create
#photo = Photo.new params[:photo]
if #parent_photo.present?
# fill some #photo fields from #parent_photo
end
#photo.save
respond_with #photo
end
def find_parent_photo
#parent_photo = Photo.find(params[:photo_id]) if params[:photo_id].present?
end
new.html.haml
= form_for [#parent_photo, #photo] do |f|
-# your form code
previously when you wanted to add a link to photo creation you wrote something like that
= link_to "new photo", [:new, :photo]
now if you want to add a link to photo creation based on foto #photo1
= link_to "new photo based on other one", [:new, #photo1, :photo]
You should be able to match a route like so:
match 'photos/new/:photo_id' => 'photos#new
or you could just pass a :photo_id parameter in the url and handle it in the controller:
'/photos/new?photo_id=17'
Example using helper method: new_photo_path(:photo_id => 17)
Edit: I don't know if this conforms to REST
It may be over the top, but you could do something like this:
class PhotoCopiesController < ApplicationController
def new
#photo = Photo.find(params[:photo_id]).dup
end
def create
end
end
and
resources :photo_copies, :only => [:new, :create]
and
= link_to 'Copy', photo_copy_path(:photo_id => #photo.id)