How can I provide .dup method with custom param so every time it is executed param is always True even when object who is being duplicated has this param at false?
Attribute I want to make true is called :original.
Here is my Modifications_controller create action:
def create
#modification = Modification.new(change_params.merge(user: current_user))
respond_to do |format|
if #modification.save
#modification.entity.boxes.each do |b|
#modification.boxes << b.dup #here I need to pass custom param
end
format.js {}
else
format.js {}
end
end
end
#dup doesn't know anything specific about your model logic. If you want to set some attributes to true, simply clone the object and then change the values.
box = b.dup
box.value = true
#modification.boxes << box
You can also consider to extract the feature in a custom method in the model, so that it's easier to write a test for it.
def duplicate
self.dup.tap do |i|
i.value = true
end
end
#modification.boxes << b.duplicate
Related
Goal: dynamically update another Model's properties (Tracker) from Controller (cards_controller.rb), when cards_controller is running the def update action.
Error I receive : NameError in CardsController#update, and it calls out the 2nd last line in the
def update_tracker(card_attribute) :
updated_array = #tracker.instance_variable_get("#{string_tracker_column}")[Time.zone.now, #card.(eval(card_attribute.to_s))]
Perceived problem: I have everything working except that I don't know the appropriate way to 'call' the attribute of Tracker correctly, when using dynamic attributes.
The attribute of the Tracker is an array (using PG as db works fine), I want to
figure out what property has been changed (works)
read the corresponding property array from Tracker's model, and make a local var from it. (works I think, )
push() a new array to the local var. This new array contains the datetime (of now) and, a string (with the value of the updated string of the Card) (works)
updated the Tracker with the correct attribute.
With the following code from the cards_controller.rb
it's the if #card.deck.tracked in the update method that makes the process start
cards_controller.rb
...
def update
#card = Card.find(params[:id])
if #card.deck.tracked
detect_changes
end
if #card.update_attributes(card_params)
if #card.deck.tracked
prop_changed?
end
flash[:success] = "Card info updated."
respond_to do |format|
format.html { render 'show' }
end
else
render 'edit'
end
end
...
private
def detect_changes
#changed = []
#changed << :front if #card.front != params[:card][:front]
#changed << :hint if #card.hint != params[:card][:hint]
#changed << :back if #card.back != params[:card][:back]
end
def prop_changed?
#changed.each do |check|
#changed.include? check
puts "Following property has been changed : #{check}"
update_tracker(check)
end
end
def update_tracker(card_attribute)
tracker_attribute = case card_attribute
when :front; :front_changed
when :back; :back_changed
when :hint; :hint_changed
end
string_tracker_column = tracker_attribute.to_s
#tracker ||= Tracker.find_by(card_id: #card.id)
updated_array = #tracker.instance_variable_get("#{string_tracker_column}")[Time.zone.now, #card.(eval(card_attribute.to_s))]
#tracker.update_attribute(tracker_attribute, updated_array)
end
Edit: For clarity here's the app/models/tracker.rb:
class Tracker < ActiveRecord::Base
belongs_to :card
end
Your use of instance_variable_get has been corrected, however this approach is destined to fail because ActiveRecord column values aren't stored as individual instance variables.
You can use
#tracker[string_column_changed]
#card[card_attribute]
To retrieve attribute values by name. If you want to get an association, use public_send. The latter is also useful if there is some accessor wrapping the column value (eg carrierwave)
From your error it seem your issue is this:
#tracker.instance_variable_get("#{string_tracker_column}")
evaluates to this after string interpolation:
#tracker.instance_variable_get("front_changed")
which is incorrect use of instance_variable_get. It needs an # prepended:
#tracker.instance_variable_get("#front_changed")
Seems like using instance_variable_get is unnecessary, though, if you set attr_reader :front_changed on the Tracker model.
I'm creating an app that lets users purchase items from an online store. I followed the RailsCasts episodes, and built my OrdersController like so.
def create
#order = current_cart.build_order(order_params)
#order.ip_address = request.remote_ip
if #order.save
if #order.purchase
Item.where(email: Order.last.email).last.purchased == true
PurchaseMailer.confirmation_email(Item.last.email).deliver
flash[:notice] = "Thanks for your purchase"
redirect_to root_path
else
flash[:danger] = "Something was wrong"
redirect_to :back
end
else
render :action => 'new'
end
end
I recently decided to add an attribute to my items, which says whether or not they've been purchased or not. Items in the cart have not yet been purchased. I created a migration, giving all items a purchased attribute, that is a boolean.
By default, items are not purchased, so the default value is false.
class AddPurchasedToItem < ActiveRecord::Migration
def change
add_column :items, :purchased, :boolean, :default => false
end
end
That's why I added this line of code to my Orders#Create action.
Item.where(email: Order.last.email).last.purchased == true
Here I was setting the value of purchased from false to true. However, when I load up rails console
Item.last.purchased
=> false
It looks like the value still isn't being stored
As another response points out, you're using the == to assign a value, which isn't right. You need = instead.
And you have to save an item after you assign a value to it.
An example:
conditions = {email: Order.last.email} # using your conditions
item = Item.find_by(conditions)
item.purchased = true
item.save # this is what you're missing
Item.find(item.id).purchased # will be true
Another way to update is the following:
item.update_attribute(:purchased, true)
Yet another way is to call update_all on the ActiveRecord::Relation object like so:
# update all items that match conditions:
Item.where(conditions).update_all(purchased: true)
Which method you choose may depend on the scenario as update_all doesn't run the callbacks you specify in the model.
In your case however, all you're missing is the item.save line.
Item.where(email: Order.last.email).last.purchased == true
You're using a == operator to try to assign a value. Try using = instead.
I have 2 models. User and Want. A User has_many: Wants.
The Want model has a single property besides user_id, that's name.
I have written a custom validation in the Want model so that a user cannot submit to create 2 wants with the same name:
validate :existing_want
private
def existing_want
return unless errors.blank?
errors.add(:existing_want, "you already want that") if user.already_wants? name
end
The already_wants? method is in the User model:
def already_wants? want_name
does_want_already = false
self.wants.each { |w| does_want_already = true if w.name == want_name }
does_want_already
end
The validation specs pass in my model tests, but my feature tests fail when i try and submit a duplicate to the create action in the WantsController:
def create
#want = current_user.wants.build(params[:want])
if #want.save
flash[:success] = "success!"
redirect_to user_account_path current_user.username
else
flash[:validation] = #want.errors
redirect_to user_account_path current_user.username
end
end
The error I get: can't dump hash with default proc
No stack trace that leads to my code.
I have narrowed the issue down to this line:
self.wants.each { |w| does_want_already = true if w.name == want_name }
if I just return true regardless the error shows in my view as I would like.
I don't understand? What's wrong? and why is it so cryptic?
Thanks.
Without a stack trace (does it lead anywhere, or does it just not appear?) it is difficult to know what exactly is happening, but here's how you can reproduce this error in a clean environment:
# initialize a new hash using a block, so it has a default proc
h = Hash.new {|h,k| h[k] = k }
# attempt to serialize it:
Marshal.dump(h)
#=> TypeError: can't dump hash with default proc
Ruby can't serialize procs, so it wouldn't be able to properly reconstitute that serialized hash, hence the error.
If you're reasonably sure that line is the source of your trouble, try refactoring it to see if that solves the problem.
def already_wants? want_name
wants.any? {|want| want_name == want.name }
end
or
def already_wants? want_name
wants.where(name: want_name).count > 0
end
What i have: (Action in Controller)
def create
#test = Test.new(params[:test])
#test.save
devicefiles = params[:devicefiles]
if devicefiles != nil
devicefiles.each do |attrs|
devicenote = Testdevicenote.new(attrs, :test_id => #test.id)
devicenote.save
end
end
end
This controller action does not show any error message and is rendering the view, but :test_id is not being saved in the database. How can i solve this?
EDIT: Ok whoops, I see it now...
Models only take one hash on initialize, not 2.
Testobjectnote.new(attrs.merge(:test_id => #test.id))
In short no one here has any clue, because that's not enough information. We dont know how your models are setup.
But when debugging models that "won't save" it's often good to use the bang version save, save!. save returns true or false letting you know if it was able to save the record. But save! will raise exceptions when the model can't be saved, and the exception will tell you why.
That exception will likely tell you why the record is not being saved.
Also, its usually better to use the associations, rather than manage the ids yourself.
def create
#test = Test.new(params[:test])
if params[:devicefiles]
params[:devicefiles].each do |attrs|
#test.testdevicenotes << Testdevicenotes(attrs)
end
end
#test.save
end
It's hard to say because you didn't post your view with the form that is posting to the create action, but if it's a typical Rails form, it should probably look like:
def create
#test = Test.new(params[:test])
#test.save
devicefiles = params[:test][:devicefiles]
if devicefiles != nil
devicefiles.each do |attrs|
devicenote = Testdevicenote.new(attrs, :test_id => #test.id)
devicenote.save
end
end
objectfiles = params[:test][:objectfiles]
if objectfiles != nil
objectfiles.each do |attrs|
objectnote = Testobjectnote.new(attrs, :test_id => #test.id)
objectnote.save
end
end
end
This assumes that :devicefiles and :objectfiles are inside the form :test
To check if buyer.save is going to fail I use buyer.valid?:
def create
#buyer = Buyer.new(params[:buyer])
if #buyer.valid?
my_update_database_method
#buyer.save
else
...
end
end
How could I check if update_attributes is going to fail ?
def update
#buyer = Buyer.find(params[:id])
if <what should be here?>
my_update_database_method
#buyer.update_attributes(params[:buyer])
else
...
end
end
it returns false if it was not done, same with save. save! will throw exceptions if you like that better. I'm not sure if there is update_attributes!, but it would be logical.
just do
if #foo.update_attributes(params)
# life is good
else
# something is wrong
end
http://apidock.com/rails/ActiveRecord/Base/update_attributes
Edit
Then you want this method you have to write. If you want to pre check params sanitation.
def params_are_sanitary?
# return true if and only if all our checks are met
# else return false
end
Edit 2
Alternatively, depending on your constraints
if Foo.new(params).valid? # Only works on Creates, not Updates
#foo.update_attributes(params)
else
# it won't be valid.
end
The method update_attributes returns false if object is invalid. So just use this construction
def update
if #buyer.update_attributes(param[:buyer])
my_update_database_method
else
...
end
end
If your my_update_database_method has to be call only before update_attributes, then you shoud use merge way, probably like this:
def update
#buyer = Buyer.find(params[:id])
#buyer.merge(params[:buyer])
if #buyer.valid?
my_update_database_method
#buyer.save
else
...
end
end
This may not be the best answer, but it seems to answer your question.
def self.validate_before_update(buyer)#parameters AKA Buyer.validate_before_update(params[:buyer])
# creates temporary buyer which will be filled with parameters
# the temporary buyer is then check to see if valid, if valid returns fail.
temp_buyer = Buyer.new
# populate temporary buyer object with data from parameters
temp_buyer.name = buyer["name"]
# fill other required parameters with valid data
temp_buyer.description = "filler desc"
temp_buyer.id = 999999
# if the temp_buyer is not valid with the provided parameters, validation fails
if temp_buyer.valid? == false
temp_buyer.errors.full_messages.each do |msg|
logger.info msg
end
# Return false or temp_buyer.errors depending on your need.
return false
end
return true
end
you'd better check it in your model through a before_save
before_save :ensure_is_valid
private
def ensure_is_valid
if self.valid?
else
end
end
I've run into the same scenario - needed to know if record is valid and do some actions before update save. I've found out that there is assign_attributes(attributes) method which update method uses before save. So nowadays it's likely correct to do:
def update
#buyer = Buyer.find(params[:id])
#buyer.assign_attributes(params[:buyer])
if #buyer.valid?
my_update_database_method
#buyer.save
else
...
end
end