Rails render issue - ruby-on-rails

Ok, another annoying problem.
I have a GuestsController that with an index action like this:
def index
#booking = Booking.find(session[:booking_id]) #i have also hard coded values to make sure the session isn't the issue
#guest = Guest.find(session[:guest_id])
end
and a personal action (to perform updates) as follows:
def personal
#guest = Guest.find(session[:guest_id])
if #guest.update(post_params)
redirect_to :controller => 'guests', :action => 'cards'
else
render 'index'
end
end
My index.html.erb view uses the #booking variable:
<%= #booking.friendly_id %> #this is one example
and also contains the form to submit the "name" field to the personal action. It updates fine if the data is valid but the #booking variable doesn't exist if it's invalid???
I need to show validation errors so I can't just use redirect_to.
The error I get is: NoMethodError in Guests#personal and undefined method `friendly_id' for nil:NilClass
Any ideas?

Just initialize the object in else part
else
#booking = Booking.find(session[:booking_id])
render 'index'
end

How about moving #booking and #guest definitions to before_filter?
before_filter do
#booking = Booking.find(session[:booking_id]) #i have also hard coded values to make sure the session isn't the issue
#guest = Guest.find(session[:guest_id])
end

There needs to be something to handle when #booking is nil - which can happen if I'm reading this right.
def index
if Booking.find(session[:booking_id])?
#booking = Booking.find(session[:booking_id])
else
#booking = Booking.build #or whatever you want here
end
#guest = Guest.find(session[:guest_id])
end

Related

Ruby on rails. Passing params from view to controller

I'm having what I assume must be a simple problem but I just can't figure it out. I'm trying to update an attribute in one model when another is created.
In my view:
<%= link_to 'Click here to rate this user', new_user_review_path(:user_id => request.user.id, :gigid => request.gig.id), remote: true %>
Which passes params :gigid and :user_id
Than my controller:
def new
#review = Review.new
#gig = Gig.find(params[:gigid])
end
def create
#review = #user.reviews.new review_params
#review.reviewed_id = current_user.id
if #review.save
#gig.update(reviewed: true)
respond_to do |format|
format.html {redirect_to session.delete(:return_to), flash[:notice] = "Thankyou for your rating!"}
format.js
end
else
render 'new'
end
end
But I get undefined method 'update'for nil:NilCLass:
I know the params are passing and the 'Gig' can be updated as :
def new
#review = Review.new
Gig.find(params[:gigid]).update(reviewed: true)
end
updates the attribute fine, but when I click 'New review' not when the review is actually created.
Adding :
def create
#review = #user.reviews.new review_params
#review.reviewed_id = current_user.id
if #review.save
Gig.find(params[:gigid]).update(reviewed: true)
etc etc etc
gives me the same undefined method 'update'for nil:NilCLass:
I have tried with find_by_id instead of find which makes no difference.
EDIT:
def create
#gig = Gig.find params[:gigid]
#review = #user.reviews.new review_params
#review.reviewed_id = current_user.id
if #review.save
#gig.update(reviewed: true)
etc etc etc
Doesn't work either. I get no errors, but the gig ID is still 'nil'.
The params are passing to the 'New' action but not the 'Create' action. I feel this should be very easy but I'm just not seeing it at the moment.
But I get undefined method 'update'for nil:NilCLass:
The error is that you have not defined #gig in your create action.
Since Rails is built on HTTP, and HTTP is stateless, you have to set the "instance" variables with each new request:
def new
#review = Review.new
#gig = Gig.find params[:gigid]
end
def create
#gig = Gig.find params[:gigid]
#review = #user.reviews.new review_params
A much better pattern for you would be to use the after_create callback in your Review model:
#app/models/review.rb
class Review < ActiveRecord::Base
belongs_to :gig #-> I presume
after_create :set_gig
private
def set_gig
self.gig.update(reviewed: true)
end
end
--
If you wanted to make the Gig update within your current setup, you'll be best sending the gig_id param through the request (not the link):
#app/views/reviews/new.html.erb
<%= form_for [#user, #review] do |f| %>
<%= f.hidden_field :gig_id, #gig.id %> #-> params[:reviews][:gig_id]
...
<% end %>
This will make params[:review][:gig_id] available in the create action, with which you'll be able to use in your code.
The problem is, you never assigned a value to #gig in your create method. I can't see your form, but you need something like this in your create method:
#gig = Gig.find params[:gigid]
Assuming that you're passing the parameter :gigid to #create
In the second example you showed, I'm not sure what's going on, but you should be getting a ActiveRecord::RecordNotFound exception on the find().
Try the below code for update operation.
gig_record = Gig.find_by_id(params[:gigid])
gig_record.update_attribute(reviewed: true) unless gig_record.blank?

Rails4: losing form validation errors while using `redirect_to` in controller

I've been trying to fix this for a while but haven't gotten anywhere yet. Would appreciate if someone could let me know how how this can be done, or if there is any way i can use the render method to do this instead (currently preserves errors but redirects to wrong path as mentioned below...)
I have a custom route for form which I am trying to redirect back when there are validation errors:
get "clubs/sign_up/:plan_id", to: "clubs#new", as: :new_membership
below is what I have so far in my controller along along with some comments regarding other steps I have tried
clubs_controller.rb
def create
#membership = Membership.new(membership_params)
if #membership.save
redirect_to root_path
else
flash[:error] = "Please check form errors:"
redirect_to new_membership_path(session[:membership_plan_id]) #errors lost
# render action: 'new', plan_id: 'silver' # <<<Preserves errors but breaks path, renders: localhost:3000/clubs instead of .../clubs/sign_up/:plan_id
# session[:membership_errors] = #membership.errors #<<< Doesn't wotk either, getting a cookie overflow error when trying to pass errors to #new
return
end
end
def new
session[:membership_plan_id] = params[:plan_id]
#membership = Membership.new
end
Assuming plan_I'd is part of your model..
Change your render line to:
render :new
Change the rest to:
def new
session[:membership_plan_id] = params[:plan_id]
#membership = Membership.new plan_id: params[:plan_id]
end
def create
#membership = Membership.new(membership_params)
if #membership.save
redirect_to root_path
else
flash[:error] = #membership.errors.full_messages.to_sentence
render :new
end
end
And add a hidden field for plan_id in your form. The reason render goes wrong is that it does not have the param available, trying to add it to the render operation does not work hence your issue
You need to render instead of redirecting. Use the ||= operator to help here.. It's all just ruby, so something like
(..snip..)
else
flash[:error] = "Problem with form"
new
end
end
def new
session[:membership_plan_id] = params[:plan_id]
#membership ||= Membership.new
render 'new'
end

Why can't I refer to my #quiz variable in 'update' action?

My QuizzesController#index action looks like this:
def index
#user = current_user
#quiz = Quiz.create(user_id: current_user.id)
end
My view draws the quiz form fine. It goes to the results/index view as intended. BUT the various attributes of the quiz are NOT updated on the Quiz instance which is pulled from the database, in the QuizzesContoller#update action:
def update
#results = Quiz.where(user_id: current_user.id).last
redirect_to results_path
end
('update' is called in this case because the Quiz instance already exists, having been created in the 'index' action).
So, I tried changing the 'update' action to:
def update
#quiz.save
#results = Quiz.where(user_id: current_user.id).last
redirect_to results_path
end
But this triggers the error:
undefined method 'save' for nil:NilClass
Why is that? Shouldn't my QuizzesController have access to the #quiz variable as set up in the 'index' action? Can anyone explain what the problem is there?
Others have answered this question, so I thought I would explain why the answer is what it is. In Ruby, variables that begin with the # symbol are instance variables. This means that they are created when a new instance of their parent object is instantiated and are unique to that instance of the object.
Rails based web apps, for the most part, are stateless, meaning that state is not persisted between http requests. In layman terms, the app treats each and every request independent of all other requests. Due to this, the controllers are instanced classes. Every request instantiates a new instance of the controller class.
EDIT:
More I look at your code, you aren't following proper conventions
class QuizzesController < ApplicationController
# GET index: for displaying a list of quizzes
def index
#quizzes = Quiz.where(user_id: current_user.id)
end
# GET show: for getting a single quiz record
def show
#quiz = Quiz.find(params[:id])
end
# GET new: for initializing a new quiz record
def new
#quiz = Quiz.new
end
# POST create: for saving a new quiz record
def create
#quiz = current_user.quizzes.create(quiz_params)
if #quiz.errors
render :new
else
redirect_to #quiz #or whereever
end
end
# GET edit: for initializing existing quiz for update
def edit
#quiz = Quiz.find(params[:id)
end
# PUT/PATCH update: for updating an existing quiz record
def update
#quiz = Quiz.find(params[:id])
if #quiz.update(quiz_params)
redirect_to #quiz # or whereever
else
render :edit
end
# DELETE destroy: for deleting a quiz record
def destroy
Quiz.find(params[:id]).destroy
redirect_to :index # or whereever
end
end
You have not #quiz variable in your update action. Actions in the controller does not have access to variables in other actions.
The QuizzesController instance is not persisted between requests. The real reason instance variables are used in controllers is to pass that variable to the view.
A normal update action would look something like:
def update
#quiz = current_user.quiz # I'm assuming a user has one quiz?
#quiz.update(quiz_params) # Where quiz params takes the posted parameters from your update form
if #quiz.errors.any?
render :edit
else
redirect_to results_path
end
The key is you need to reassign #quiz with each request

Send parameter to render

I have a form for creating a ticket, which needs an id of a project. This works but not when it comes to validation. If validation won't pass 'render :new' is executed and the project_id doesn't come with it.
I have tried 'redirect_to new_ticket_path(:project_id => params[:ticket][:project_id]) which renders the form again, but the error messages won't show up so it seems that I need to use 'render :new'.
How can I pass the project_id back to the form or reach project_id from the form without passing it?
def new
#ticket = Ticket.new
#id = params[:project_id]
#project = Project.find(#id)
end
def create
#ticket = Ticket.new(params[:ticket].merge(:user_id => current_user.id))
if #ticket.save
redirect_to #ticket
else
render :new <--- will render without the project_id
end
end
That will render just the view for 'new', but will not run the controller action. You'd need to set up your variables for the 'new' view in your 'create' action.
From http://guides.rubyonrails.org/layouts_and_rendering.html#using-render
Using render with :action is a frequent source of confusion for Rails
newcomers. The specified action is used to determine which view to
render, but Rails does not run any of the code for that action in the
controller. Any instance variables that you require in the view must
be set up in the current action before calling render.
The easiest way around this is to change 'new':
def new
#ticket = Ticket.new(:project_id => params[:project_id])
end
and change any references to #project in your 'new' form to #ticket.project. At that point, you shouldn't have to add anything to your 'create' action as long as your form includes a hidden field for the ticket's project id.
The easiest way to get this working (and I would do this anyway) is to nest the task resource under projects. That way you will always have project_id available in params.
# config/routes.rb
resources :projects do
resources :tasks
end
The urls will look like projects/123/tasks/new etc. Take a look at rake routes.
Write project id into a hidden field in your form and you will okay. And don't forget to initialize #id in your create action
def new
#ticket = Ticket.new
#id = params[:project_id]
#project = Project.find(#id)
end
def create
#ticket = Ticket.new(params[:ticket].merge(:user_id => current_user.id))
#id = params[:project_id] # but make sure it is under this key in params
if #ticket.save
redirect_to #ticket
else
render :new <--- will render without the project_id
end
end
and in the form add
<%= hidden_field :project_id, '', value: #id %>
Why don't you use:
flash[:alert] = #ticket.errors.inspect
redirect_to new_ticket_path(:project_id => params[:ticket][:project_id])

New acts like create

In my create action, method new acts like create.
def create
#page = Page.new(params[:page].merge(:user_id => current_user.id ))
if #page.save
flash[:notice] = t("success")
redirect_to pages_path
else
render :new
end
end
ActiveRecord creates new object in database while I'm using new with params. Page.new works fine in new action in my controller. What can be the reason? There is no overridden method new and no callbacks (before_save, before_create etc) in my model. Any help would be appreciated.
UPDATE - code from debugger
.../app/controllers/pages_controller.rb:48
#page = Page.new(params[:page].merge(:user_id => current_user.id ))
(rdb:25) #page
nil
(rdb:25) n
.../app/controllers/pages_controller.rb:49
if #page.save
(rdb:25) #page
#<Page id: 80 ... >
(rdb:25) Page.last
#<Page id: 80 ... >
(rdb:25) #page.save
false
Check my inline comments..
def create
#page = Page.new(params[:page].merge(:user_id => current_user.id )) # you trigger new thats fine..
if #page.save # Notice here.. This line is triggering query on database.
flash[:notice] = t("success")
redirect_to pages_path
else
render :new
end
end
Reason (method in model which can change status in workflow):
def status=(state_name)
states = [self.current_state.to_sym]
possible_states.each {|t| states<< t[1]}
unless state_name.blank?
if states.include? state_name
process_event! state_name
end
end
end
Ugly fix
def create
#page = Page.new
if #page.update_attributes(params[:page].merge(:user_id => current_user.id )) && #page.save
flash[:notice] = t("success")
redirect_to pages_path
else
render :new
end
end
Mistake was quite silly and I'm not proud of my solution. Anyway, thanks for help:)
With an ActiveRecord class, create = new + save
https://github.com/rails/rails/blob/7edade337e968fb028b2b6abfa579120eb424039/activerecord/lib/active_record/persistence.rb#L40
Your controller code is correct. This is how a 'create' controller method should work. The problem is not there.
Are you certain you're having two models created?
The .new method you're calling with the attributes creates an activerecord object in memory that's unsaved. The .save method saves it. At the end (assuming the data is valid) you should have a single object in memory.
If you have two objects created, then there is a problem. If you have only one, then it's as it should be.
Are you having a second object created by this controller method?
The process should be:
# when GET /student/new is called, this returns an empty object to display in the form
# for the user to see.
def new
#page = Page.new
end
# When POST /page is called, the form params are passed in here.
def create
# First, generate a new page object with the params passed in.
#page = Page.new(params[:page].merge(:user_id => current_user.id ))
# Now try save the object to persist it in the database.
if #page.save
flash[:notice] = t("success")
redirect_to pages_path
else
render :new
end
end

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