I have a custom validator that checks if the user has entered the correct SMS code. When the user enters the wrong code I need to log the failed attempt and limit their retries to 3 per code.
I have created the following validator that works however the field is not being incremented.
def token_match
if token != User.find(user_id).verification_token
User.find(user_id).increment!(:verification_fails)
errors.add(:sms_code, "does not match")
end
end
The problem is as soon as I add the error the previous statement is rolled back. If I comment out the errors.add line then the increment works however there is no higher level validation performed.
Change your custom validator to be:
def token_match
if token != User.find(user_id).verification_token
errors.add(:sms_code, "does not match")
end
end
and add in your model after_validation callback to be like this:
after_validation: increase_fails_count
def increase_fails_count
unless self.errors[:sms_code].empty?
user = User.find_by(:id => user_id)
user.increment!(:verification_fails)
user.save
end
end
You can use #update_columns in your validator. It writes directly to db.
u = User.find(user_id)
u.update_columns(verification_fails: u.verification_fails + 1)
This worked for me. But if for some reason it doesn't work for you, maybe you can try running it in a new thread,which creates a new db connection:
Thread.new do
num = User.find(user_id).verification_fails
ActiveRecord::Base.connection_pool.with_connection { |con| con.exec_query("UPDATE users SET verification_fails = #{num} WHERE id = #{user_id}") }
end.join
Related
Some records in my application have a DOI assigned to them and in that case they should not be deleted. Instead, they should have their description changed and be flagged when a user triggers their deletion. A way to do this, I thought, would be as follows in the relevant model:
before_destroy :destroy_validation
private
def destroy_validation
if metadata['doi'].blank?
# Delete as normal...
nil
else
# This is a JSON field.
modified_metadata = Marshal.load(Marshal.dump(metadata))
description = "Record does not exist anymore: #{name}. The record with identifier content #{doi} was invalid."
modified_metadata['description'] = description
modified_metadata['tombstone'] = true
update_column :metadata, modified_metadata
raise ActiveRecord::RecordNotDestroyed, 'Records with DOIs cannot be deleted'
end
end
This does indeed prevent deletion, but the record appears unchanged afterwards rather than having a modified description. Here's an example of a test:
test "records with dois are not deleted" do
record = Record.new(metadata: metadata)
record.metadata['doi'] = 'this_is_a_doi'
assert record.save
assert_raises(ActiveRecord::RecordNotDestroyed) { record.destroy! }
assert Record.exists?(record.id)
modified_record = Record.find(record.id)
puts "#{record.description}" # This is correctly modified as per the callback code.
puts "#{modified_record.description}" # This is the same as when the record was created.
end
I can only guess that Rails is rolling back the update_column due to an exception having been raised, though I may be mistaken. Is there anything I can do to prevent this?
save and destroy are automatically wrapped in a transaction
https://api.rubyonrails.org/classes/ActiveRecord/Transactions/ClassMethods.html
So destroy fails, transactions is rolled back and you can't see updated column in tests.
You could try with after_rollback callback https://api.rubyonrails.org/classes/ActiveRecord/Transactions/ClassMethods.html#method-i-after_rollback
or do record.destroy check for record.errors, if found update record with method manually record.update_doi if record.errors.any?.
before_destroy :destroyable?
...
def destroyable?
unless metadata['doi'].blank?
errors.add('Doi is not empty.')
throw :abort
end
end
def update_doi
modified_metadata = Marshal.load(Marshal.dump(metadata))
description = "Record does not exist anymore: #{name}. The record with identifier content #{doi} was invalid."
modified_metadata['description'] = description
modified_metadata['tombstone'] = true
update_column :metadata, modified_metadata
end
Tip: use record.reload instead of Record.find(record.id).
i have a model which defines size ranges like 100m² to 200m². I wrote a validator:
class SizeRange < ActiveRecord::Base
validate :non_overlapping
def non_overlapping
lower_in_range = SizeRange.where(lower_bound: lower_bound..upper_bound)
upper_in_range = SizeRange.where(upper_bound: lower_bound..upper_bound)
if lower_in_range.present?
errors.add(:lower_bound, 'blablabla')
end
if upper_in_range.present?
errors.add(:upper_bound, 'blablabla')
end
end
end
My guess was, that when I try to save a new model which lower or upper bound appears to be in the range of an other SizeRange instance the validator would mark the model as invalid and the save action would be aborted.
What really happened is that my model got saved and assigned an id, but when I call model.valid? it returns false (So my validator seems to do what it should).
Is there anything I could have done wrong, or did I not understand how the validators work? Can I force the validator to abort the save action?
Another question:
Is there any way to enforce a constraint like that through database constraints? I think I would prefer a solution on database side.
Thanks for your help!
model.save
would be accepted silently and return false. It will not throw any Exception.
You should call:
model.save!
to fail with validations
You should return false after each errors.add to cancel the record saving
Turns out the problem was my not well-formed validator function.
The case I checked an which led to confusion:
SizeRange from 200 to 400 already in the database
Creating a new one between 200 and 400 like SizeRange.new({:lower_bound=>250, :upper_bound=>350})
So I expected that to be invalid (model.valid? -> false) but it was, of course, valid. So model.save did no rollback and AFTER that I tested on model.valid? which would NOW return false, as the newly saved instance would violate the constraint, because it was tested against itself.
So there were two problems:
model.valid? would also test against the same instance if it already had an id
the validator would not validate what I thought it would
So I ended up rewriting my validator function:
def non_overlapping
sr = id.present? ? SizeRange.where.not(id: id) : SizeRange
ranges = sr.all
lower_overlappings = ranges.map { |r| lower_bound.between?(r.lower_bound, r.upper_bound)}
upper_overlappings = ranges.map { |r| upper_bound.between?(r.lower_bound, r.upper_bound)}
if lower_overlappings.any?
errors.add(:lower_bound, 'lower bla bla')
end
if upper_overlappings.any?
errors.add(:lower_bound, 'upper bla bla')
end
end
The first line handles the first problem and the rest handles the intended validation.
Thanks for your help and sorry for the confusion.
You should be using begin and rescue:
class SizeRange < ActiveRecord::Base
validate :non_overlapping
private
def non_overlapping
lower_in_range = SizeRange.where(lower_bound: lower_bound..upper_bound)
upper_in_range = SizeRange.where(upper_bound: lower_bound..upper_bound)
begin
raise("Lower Bound Met!") if lower_in_range.present?
rescue => ex
errors.add(:lower_bound, "#{ex.message} (#{ex.class})")
end
begin
raise("Lower Bound Met!") if upper_in_range.present?
rescue => ex
errors.add(:upper_bound, "#{ex.message} (#{ex.class})")
end
end
end
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
Given the following method
def change_plan_to(plan_id)
new_plan = Plan.find plan_id
stripe_customer = Stripe::Customer.retrieve(stripe_customer_token)
stripe_customer.update_subscription(plan: new_plan.slug)
self.plan = new_plan
self.active = true
save
rescue Stripe::InvalidRequestError => e
logger.error "[STRIPE] #{ e }"
errors.add :base, "Unable to change your plan!"
false
end
Specifically line #4-6. I want 4 and 5 to happen only if 4 is successful but Stripe doesn't return the ability to wrap that in a if. If it errors it just throws Stripe::InvalidRequestError.
What's the best way to handle this? Fire & forget and allow Stripe webhook callbacks to manage expiring active state as needed?
The other scenario is that all the code will halt after line 4 if it doesn't pass. Is this how rescue works?
Yes thats the way rescue work,
So better you execute these statements which is dependent on line 4 in webhook callbacks that stripe sends to you. Because that ensures subscription change.
I have a delayed_job designed to send an email using a mailer.
Upon completion, I need to record that the email was sent -- I do this by saving the newly created ContactEmail.
Right now, the new ContactEmail records gets saved even if the delayed_job fails.
How do I correct that so that the new ContactEmail is only saved when the mailer is successfully sent?
Here is the snippet from the cron task which calls the delayed_job:
puts contact_email.subject
contact_email.date_sent = Date.today
contact_email.date_created = Date.today
contact_email.body = email.substituted_message(contact, contact.colleagues)
contact_email.status = "sent"
#Delayed::Job.enqueue OutboundMailer.deliver_campaign_email(contact,contact_email)
Delayed::Job.enqueue SomeMailJob.new(contact,contact_email)
contact_email.save #now save the record
Here is the some_mail_job.rb
class SomeMailJob < Struct.new(:contact, :contact_email)
def perform
OutboundMailer.deliver_campaign_email(contact,contact_email)
end
end
And here is the outbound_mailer:
class OutboundMailer < Postage::Mailer
def campaign_email(contact,email)
subject email.subject
recipients contact.email
from '<me#me.com>'
sent_on Date.today
body :email => email
end
You could update the status in the perform of the job itself.
For example, something like:
contact_email.status = 'queued'
contact_email.save
contact_email.delay.deliver_campaign_email
And then in your ContactEmail class, something to the effect of
def deliver_campaign_email
OutboundMailer.deliver_campaign_email(self.contact, self)
self.status = 'sent' # or handle failure and set it appropriately
self.save
end
delayed_job has some magic bits that it adds to your models that will deal with the persistence.
In order to deal with your OutboundMailer throwing an exception, you can do something like so:
def deliver_campaign_email
begin
OutboundMailer.deliver_campaign_email(self.contact, self)
self.status = 'sent'
rescue
self.status = 'failed' # or better yet grab the the message from the exception
end
self.save
end
You need synchronic delivery so stop using delayed job in this case and do standard mailer delivery.
or add success column to you ContactEmail - initialy save it with false then update in job to true