Cookie Overflow Bug upon creating Reservation

[AlanLiu96]

The elusive cookie overflow bug that has been cropping up for a while now.

Not sure what exactly causes it, but here are the list of steps I followed to successfully reproduce it as Superuser

1. Create an equipment model with ~ 20 available equipment Items
2. Put that equipment model into your cart. Try to check out 10000 (or any other VERY large number of them).
3. At checkout page, fill in text for explanation. and press checkout. You will be redirected to catalog as expected.
4. Repeat steps 2-3 a couple of times with decreasing numbers of items Ex. 10000 --> 1000 --> 500 --> 100
   (not sure how many times is necessary, but my suspicion is that this part is essential to "filling up" the cookies) Also not sure if changing quantities on the catalog page is sufficient, or if its necessary to change quantities on the checkout page.
5. Try to check out 20 of the item.
6. The reservation will successfully be created, but you will be redirected to a CookieOverflow error.

[AlanLiu96]

Not sure if this is an issue, but the session dump says the flash was pretty full. Full log below.

cart: #<Cart:0x00563a70b351e0 @errors=#<ActiveModel::Errors:0x00563a71307aa8 @base=#<Cart:0x00563a70b351e0 ...>, @messages={}>, @items={}, @start_date=Sat, 05 Mar 2016, @due_date=Sun, 06 Mar 2016, @reserver_id=nil>
flash: {"discard"=>[], "flashes"=>{"notice"=>"Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones..\n Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones..\n Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones. and Only 2 Sonix GPS Input Mount 2398s can be reserved at a time..\n Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones., Only 2 Sonix GPS Input Mount 2398s can be reserved at a time., and Only 3 Trents can be reserved at a time..\n Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones., Only 2 Sonix GPS Input Mount 2398s can be reserved at a time., and Only 3 Trents can be reserved at a time..\n Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones., Only 2 Sonix GPS Input Mount 2398s can be reserved at a time., and Only 3 Trents can be reserved at a time..\n Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones., Only 2 Sonix GPS Input Mount 2398s can be reserved at a time., and Only 3 Trents can be reserved at a time..\n Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones., Only 2 Sonix GPS Input Mount 2398s can be reserved at a time., and Only 3 Trents can be reserved at a time..\n Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones., Only 2 Sonix GPS Input Mount 2398s can be reserved at a time., and Only 3 Trents can be reserved at a time..\n Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones., Only 2 Sonix GPS Input Mount 2398s can be reserved at a time., and Only 3 Trents can be reserved at a time..\n Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones., Only 2 Sonix GPS Input Mount 2398s can be reserved at a time., and Only 3 Trents can be reserved at a time..\n Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones., Only 2 Sonix GPS Input Mount 2398s can be reserved at a time., and Only 3 Trents can be reserved at a time..\n Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones., Only 2 Sonix GPS Input Mount 2398s can be reserved at a time., and Only 3 Trents can be reserved at a time..\n Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones., Only 2 Sonix GPS Input Mount 2398s can be reserved at a time., and Only 3 Trents can be reserved at a time..\n Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones., Only 2 Sonix GPS Input Mount 2398s can be reserved at a time., and Only 3 Trents can be reserved at a time..\n Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones., Only 2 Sonix GPS Input Mount 2398s can be reserved at a time., and Only 3 Trents can be reserved at a time..\n Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones., Only 2 Sonix GPS Input Mount 2398s can be reserved at a time., and Only 3 Trents can be reserved at a time..\n Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones., Only 2 Sonix GPS Input Mount 2398s can be reserved at a time., and Only 3 Trents can be reserved at a time..\n Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones., Only 2 Sonix GPS Input Mount 2398s can be reserved at a time., and Only 3 Trents can be reserved at a time..\n Reservation for [Sonix GPS Input Mount 2398](http://0.0.0.0:3000/equipment_models/5) created successfully, even though this user has overdue reservations that prevent him/her from creating new ones., Only 2 Sonix GPS Input Mount 2398s can be reserved at a time., and Only 3 Trents can be reserved at a time..\n Are you simultaneously checking out equipment for someone? Note that only the reservation has been made. Don't forget to continue to checkout."}}
index_end_date: Mon, 07 Mar 2016
index_start_date: Mon, 22 Feb 2016
items_per_page: 10
session_id: "664fa0da5b39f98da34553f9b1f1a80a"
warden.user.user.key: [[1], "$2a$10$K72fL.g/VmgBkymSdbL5Fe"]

[orenyk]

FYI, I was able to replicate this without adding too many items to the cart first. Here's what I did:

1. Use rake db:seed to create 1000 equipment items - this meant that at least one of my equipment models had over 20 equipment items.
2. Have an overdue reservation already (from testing No method error when checking out for person with overdue item #1486).
3. Add 20 items to the cart (this violated both the equipment model-based and category-based checkout limits).
4. Force create the reservations.

I'm 99% sure that this is in fact a flash issue since if you subsequently reload everything is fine and the cart has not been reset, but the flashes are no longer in the session for the new request. It's honestly more of an edge case since I don't think people often create more than 5 reservations simultaneously, definitely not with that many violated validations, but we should still limit the flashes.... maybe count the number of elements in @errors and truncate them if necessary? Let's address this in our next sprint.

[AlanLiu96]

Was able to truncate the elements in '''@errors''' resolving the issue. Would it be worth creating a test for this, since it would require essentially generating many items to get multiple errors overflowing flash?

[orenyk]

So I would recommend writing a unit test to simply check that the @errors array is properly truncated (in spec/models/cart_spec.rb), as opposed to an integration test. You don't need to actually generate real errors to test this, just assign a representative array directly and check that when you then try to access it, it's properly truncated. Let me know if that makes sense!