Render does not run action - ruby-on-rails

I am using almost the code from the regular scaffold. The only change is the 4.times block where I make 4 answer objects on the question. The reason is that I have the corresponding input fields in the view. Now, if the validation fails it renders the new.html.erb again, however after what I have been reading it does not invoke the "new" action again. However I am depending on the 4.times block because otherwise the loop in the view have no answers to loop through. How do I fix this? I tried redirecting but then the error messages disappered.
New action
def new
#question = Question.new
4.times do
#question.answers.build
end
respond_to do |format|
format.html # new.html.erb
format.json { render json: #question }
end
end
Create action
def create
#question = Question.new(params[:question])
respond_to do |format|
if #question.save
format.html { redirect_to #question, notice: 'Question was successfully created.' }
format.json { render json: #question, status: :created, location: #question }
else
format.html { render action: "new" }
format.json { render json: #question.errors, status: :unprocessable_entity }
end
end
end

Exactly as your title suggests: render does just render (the template belonging to) the action and not perform the action itself.
To get your prebuilt answers rendered again in a failed create call, I suggest removing the :reject_if condition from the nested attributes setup. This way, empty submitted answers are preserved. To prevent them from being written to the database, just add regular validations to the Question model...

What you need to look at is the #question in your create action. In theory it should contain the 4 newly built answers so redisplaying the form would also contain these.
If they are not written you may have to look at the accepts_nested_attributes_for to make sure it gets deserialized correctly from the request.

Related

Editing Triple Nested Fields is Creating Duplicates Rails 5.1

I have a triple nested resource, which I am able to create new values for perfectly well. However when trying to edit the record, I am getting duplicated fields for the nested values, which is then creating multiple entries.
I am multiplying the nested fields by 3.
def new
#roast = Roast.new
3.times {#roast.countries.build.regions.build}
end
Edit method:
def edit
#roast = Roast.friendly.find(params[:id])
3.times {#roast.countries.build.regions.build}
end
Should I be removing the 'build' element here? I do want the user to be able to add new values if required however.
And create has nothing special for this:
def create
#roast = Roast.new(roast_params)
respond_to do |format|
if #roast.save
format.html { redirect_to #roast, notice: 'Roast was successfully created.' }
format.json { render :show, status: :created, location: #roast }
else
format.html { render :new }
format.json { render json: #roast.errors, status: :unprocessable_entity }
end
end
end
I obviously want the 3 nested fields to show on the edit page, but what am I doing wrong for it to keep repeating.
You don't need to add countries or regions in the edit. Just find the Roast.
#This is wrong
3.times {#roast.countries.build.regions.build}
When you edit a Roast, you can access its countries through #roast.countries
If you want, you can define an instance variable to use in the form (although not needed) #countries = #roast.countries

Create more than one object at once using the standard create method in Ruby on Rails

I am trying to use the standard create method created for Ruby/Rails projects and simply pass in an additional form field that tells the method how many objects to create (vs just creating one object). The standard create method looks like so:
def create
#micropost = Micropost.new(micropost_params)
respond_to do |format|
if #micropost.save
format.html { redirect_to #micropost, notice: 'Micropost was successfully created.' }
format.json { render :show, status: :created, location: #micropost }
else
format.html { render :new }
format.json { render json: #micropost.errors, status: :unprocessable_entity }
end
end
end
I want to pass in an additional data (form field called number_to_create) which tells the method how many of the microposts to create. I just added a new form field like this, in addition to the other micropost form field params:
<%= text_field_tag :number_to_create %>
My question is how do I modify the create method code such that it creates N number of micropost objects vs. just one. So if I pass in 3 from the form along with the other micropost attributes, the method creates 3 identical micropost objects, not just one as it currently does.
Thanks in advance for your help on this.
You could use the param as times
#microposts = Micropost.transaction do
[].tap do |microposts|
param[:number_to_create].times do
microposts << Micropost.create(micropost_params)
end
end
end
respond_to do |format|
if #microposts.all? &:persisted?
format.html { redirect_to #micropost, notice: 'Micropost was successfully created.' }
format.json { render :show, status: :created, location: #micropost }
else
format.html { render :new }
format.json { render json: #micropost.errors, status: :unprocessable_entity }
end
end
The transaction block is to make sure that either all of them gets saved, or none of them gets saved, this way you can fix your errors and recreate them without worrying of getting any stray saved objects

Rendering a partial from a controller in rails

I have a form that is adding rows to the DB via remote => true. I then want to append the new data to a table, but cannot get the correct view to render.
As of now, it is rendering the entire show.html.erb page for the new entry, but I want to layout a minimal version to be added as a . Is there a quick way to tell my controller what view to render after inserting into the db? I want to render my partial named _newly_added.html.erb
My Controller
def new
#task = Task.new
render :partial => "/tasks/newly_added", :locals => { :t => #task }
end
Thanks!!
EDIT
I think what I need is just an alternative "show" view.
I found that the method I needed to change was actually this:
def create
#task = Task.new(params[:task])
respond_to do |format|
if #task.save
format.html { redirect_to #task, notice: 'Task was successfully created.' }
format.json { render json: #task, status: :created, location: #task }
else
format.html { render action: "new" }
format.json { render json: #task.errors, status: :unprocessable_entity }
end
end
end
I just need to make an alternative show view, and then tell this to redirect_to that view.
Edited per the changes in your question. However, nothing really changes. You're thinking about things wrong, and need to adjust how you're thinking. You don't need an alternative show, you need to handle the format.js request.
The partial should be rendered within a JavaScript response, not the controller. The controller looks more like this:
def create
#task = Task.new(params[:task])
respond_to do |format|
if #task.save
format.html { redirect_to #task, notice: 'Task was successfully created.' }
format.json { render json: #task, status: :created, location: #task }
format.js
else
format.html { render action: "new" }
format.json { render json: #task.errors, status: :unprocessable_entity }
format.js
end
end
end
Then, in views/tasks/create.js.coffee
($ '#mytable').append("<%= j render(partial: 'tasks/newly_added', locals: { t: #task }) %>")
What's going on here is that the browser makes a call to create.js. The controller responds with the create.js template, because of the respond_to block's format.js. The j escapes the contents of the _newly_added.html.erb file, and the contents of it are appended to the table. The controller doesn't interact with the existing view, instead, JavaScript is sent to the browser, and it interacts with the view.
This all changes somewhat if you're using a client-side MVC framework like Backbone or Ember, but you didn't specify that so I'm assuming you're going with stock Rails.

Action won't render on validation fail

I have a fairly standard controller with a create method and some validations.
def create
#type = Type.new(params[:type])
respond_to do |format|
if #type.save
format.html { redirect_to types_path, notice: 'Type was successfully created.' }
format.json { render json: #type, status: :created, location: #type }
else
format.html { render action: "new" }
format.json { render json: #type.errors, status: :unprocessable_entity }
end
end
end
The problem is that when a validation fails, I get the errorMissing template ontology/types/create, as if the render action: "new" weren't there. If I replace it with a redirect_to then it works as expected, but then it seems I can't pass the form errors along.
I know that there is a #type instance (with #type.errors) from the original call of new, and throwing it just before the render call confirms this.
The same thing is happening when a validation fails on update It seems like the render call is just being ignored!
NOTE: my routing structure is a little unconventional, but I see not reason why this should be related.
This looks very similar: Path defined in controller and action is getting ignored, Ruby on Rails
Based on the answer to that question, I'm guessing that something is missing that is needed for rendering the new view, and as a result rails is just skipping the render call altogether and rendering create.
Can you show the new controller action and view?

Using .dup and .update_attributes to generate a model instance is causing creation of extra instances upon failing validation

I have a validation for the Activity model and this is the create action in the activities_controller. When I try to save the model without meeting the validations, an extra activity instance is being created. Why is an activity being created when it fails the validations?
def create
#activity_last = Activity.find(params[:activity_id])
#activity = #activity_last.dup
#activity.activity_date = Time.now
respond_to do |format|
if #activity.update_attributes(params[:activity])
format.html { redirect_to #activity.tenant, notice: 'Activity was successfully created.' }
format.json { render json: #activity.tenant, status: :created, location: #activity.tenant }
else
format.html { render action: "new" }
format.json { render json: #activity.errors, status: :unprocessable_entity }
end
end
end
The reason I am using dup here is because I want to create a duplicate of the latest activity and then update a subset of its attributes from the params. So for explanation sake, say Activity had 10 attributes. The user would go to a form that has field for 3 of these attributes. I then want to create a new activity that has all the same attribute values as the latest activity for the attributes not being updated by the user.
--Update--
I have uncovered why this was happening. I shortened the code above so that there would be less clutter but as part of that shortening I cut out the following lines:
#comment = Comment.new(params[:comment])
#comment.user = current_user
#comment.activity = #activity
#comment.save!
The app works correctly when I move the saving of the comment to after the saving of the activity. My guess is that saving a comment that is linked to an activity that hasn't been saved causes the activity to be saved?

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