'm trying to tweek Spree to my needs and I've hit a bump. I'll try to explain as best as I can without pasting too much code, 'cause Spree has quite a lot of it...
For starters. I've extended OptionType like this
Spree::OptionType.class_eval do
PRODUCT_TYPES = SuperMap.new( [:default, 0],
[:vehicle_bonnet, 1],
[:vehicle_images, 2])
super_mapped_attr :product_type, PRODUCT_TYPES
attr_accessible :product_type
end
I want to check in the show view of the ProductsController what sort of product_type I'm dealing with, like this:
<% if #product.option_types.product_type_key == :vehicle_bonnet %>
...
<% end %>
and I get undefined method ``product_type_key'. This method should be available thanks to SuperMap.
Now, the Product and OptionType has a bit strange association (for me at least).
module Spree
class Product < ActiveRecord::Base
has_many :product_option_types, :dependent => :destroy
has_many :option_types, :through => :product_option_types
end
end
so far seems to be ok.
module Spree
class ProductOptionType < ActiveRecord::Base
belongs_to :product
belongs_to :option_type
acts_as_list :scope => :product
end
end
and now comes the weird part:
module Spree
class OptionType < ActiveRecord::Base
has_many :option_values, :order => :position, :dependent => :destroy
has_many :product_option_types, :dependent => :destroy
has_and_belongs_to_many :prototypes, :join_table => 'spree_option_types_prototypes'
attr_accessible :name, :presentation, :option_values_attributes
validates :name, :presentation, :presence => true
default_scope :order => "#{self.table_name}.position"
accepts_nested_attributes_for :option_values, :reject_if => lambda { |ov| ov[:name].blank? || ov[:presentation].blank? }, :allow_destroy => true
end
end
this is actually the whole OptionType model. What suprises me it doesn't have has_many :products, through: :product_option_types. I've tried to add this line to my extension, but didn't help. I've tried few other thing of course, but it just made such a mess I went back to this version, since I think it shows best what I'm trying to achieve. What am I missing?
EDIT (solved, I should hope so...):
Turned out that in the Product model there was an alias alias :options :product_option_types, which was (imho) in the wrong place, because somewhere in the middle of a quite a long model (I should think it should have been somewhere closer to the has_many, but that's just me).
Further more, the options turned out to be an array, no that shocking come to think of it. So, what I did is extended the product model, added a method, where I'm checking the product_type_key, like so:
def type_of_product?(type)
options.each do |opts|
if opts.option_type.product_type_key == type
return true
end
end
false
end
Not the prettiest method, but it works as I expect it to...
Related
I am having performance issues on one of my api views so I ran the Bullet gem and found some major N+1 issues with the view.
The api is being consumed so the format has to remain identical.
Bullet N+1 output:
localhost:3000/api/v1/games/1/game_feed N+1 Query detected
CompletedQuest => [:comments] Add to your finder: :include =>
[:comments] N+1 Query method call stack
/app/views/api/v1/games/game_feed.json.jbuilder:3:in block in
_b3b681b668d1c2a5691a5b3f7c15bb8e' /app/views/api/v1/games/game_feed.json.jbuilder:1:in
_b3b681b668d1c2a5691a5b3f7c15bb8e'
But I don't know how to accomplish the fix. Here are the relevant parts.
View:
json.game_feed(#game_photos) do |f|
json.extract! f, :id, :user_id, :username, :image_url_original, :comments_count, :likes_count
json.comments f.comments do |comment|
json.(comment, :username, :comment)
end
json.likes f.likes do |like|
json.(like, :id, :user_id, :username)
end
end
Controller:
#game_photos = CompletedQuest.game_photos(#game.id)
Model:
def self.game_photos(game_id)
where("completed_quests.game_id = ?", game_id).order("completed_quests.id DESC").just_photos
end
scope :just_photos, -> { where.not( image_file_name: nil ) }
Model relationships:
# CompletedQuests:
belongs_to :user
has_many :comments, dependent: :destroy
has_many :likes, dependent: :destroy
# Comments:
belongs_to :completed_quest, counter_cache: true
belongs_to :user
So basically for each photo in the feed, it then grabs every comment & likes for ever record - obviously this is bad and I see why, but I can't figure out how to fix it with my current structure.
Any help would be appreciated - but one thing is the structure of the JSON must remain identical.
You could include the associated comments in the query as follows:
# app/models/completed_quest.rb
def self.game_photos(game_id)
includes(:comments).where("completed_quests.game_id = ?", game_id).order("completed_quests.id DESC").just_photos
end
This will include all the associated comments in the result, so when you do f.comments in your view, there won't be a database query for comments of each f instance.
Im building a report system which uses a sort of meta question model. Questions are previusly saved in the database, and then depending of the type of report some questions are taken from the database.
Wanting to keep things DRY, i'm trying to figure out a way to pass the information of the Variable model to my report_header with no avail.
In the new action i have:
reportBody = #report_head.report_bodies.build(:variable_id => a.id)
#report_head.variables #modified, thx.
all i need is to pass the attributes from the Variable to report_head in a DRY way.
If you need to know my models:
class Variable < ActiveRecord::Base
attr_accessible :id,:break_point, :description, :name, :time_frequency, :v_type
has_many :report_bodies
has_many :report_heads, :through => :report_bodies
end
class ReportHead < ActiveRecord::Base
attr_accessible :email, :name , :report_bodies_attributes, :report_bodies, :variables_attributes
has_many :report_bodies
has_many :variables, :through => :report_bodies
accepts_nested_attributes_for :report_bodies
end
class ReportBody < ActiveRecord::Base
attr_accessible :report_head_id, :variable_value, :variable_id, :variables_attributes, :report_heads
belongs_to :report_head
belongs_to :variable
end
Update
I updated the model as suggested, and modified the way to call the variables. However im still confused about how to use it in the view, if i do something like:
<%= f.fields_for :variables do |variable| %>
<%= variable.text_field :name, :value => :name, :class => 'text_field' %>
<% end %>
it prints a string instead of the actual name.
You have define wrong name association, your association of ReportBody should be:
belongs_to :report_head
belongs_to :variable
This is not correct:
#report_head.report_bodies.build(:variable_id => a.id,:report_head_id =>#report_head.id)
chang it to:
#report_head.variables.build(:variable_id => a.id)
it's better, you don't have to set report_head_id. And this is wrong:
#report_head.report_bodies.variables
If you want to get all variables belong to #report_head, you just need using:
#report_head.variables
I have 2 models
class Variant < ActiveRecord::Base
belongs_to :product
with_options :if => :is_active? do |p_active|
p_active.validates :avatar, :presence => true
end
with_options :if => :isnt_diavoleria? do |p_active|
p_active.validates :color, :presence => true
end
def is_active?
self.product.active
end
def isnt_diavoleria?
a = (self.is_active? and self.product.section_id != 5)
a
end
end
class Product < ActiveRecord::Base
has_many :variants, :autosave => true
accepts_nested_attributes_for :variants
end
If i change the attribute section_id or active of a product and save, the validations of the model variant are executed with the old values of section_id and active.
Why?
How can i do the validations with the new values?
The problem is that by default a pair of has_many and belongs_to associations don't know that they are the inverse of each other. So when you
product.section_id = 23
product.save
then inside your validation, the variant goes
self.product
and actually fetches that from the database again, which obviously doesn't have your unsaved change.
You should be able to fix this by adding the :inverse_of flag to your associations, i.e.
class Variant < AR::Base
belongs_to :product, :inverse_of => :variants
end
class Product < AR::Base
has_many :variants, :inverse_of => :products
end
One day rails will have an identity map which should make this sort of stuff less error prone (it is in rails 3.1 but disabled because of subtle associated bugs if i remember correctly)
You probably need to do what #thoferon is suggesting (assuming you aren't doing taking nested attributes for products or something) or make sure all changes to the product are happening through the association object so it is up-to-date.
Maybe you are modifying a product through another Ruby object. The product referenced by the variant is still holding the old values. I don't know if this is what you're doing but it could be the case.
A solution could be to reload the product before validation.
class Variant
before_validation do
self.product.reload
end
end
I've search everywhere for a pointer to this, but can't find one. Basically, I want to do what everyone else wants to do when they create a polymorphic relationship in a :has_many, :through way… but I want to do it in a module. I keep getting stuck and think I must be overlooking something simple.
To wit:
module ActsPermissive
module PermissiveUser
def self.included(base)
base.extend ClassMethods
end
module ClassMethods
def acts_permissive
has_many :ownables
has_many :owned_circles, :through => :ownables
end
end
end
class PermissiveCircle < ActiveRecord::Base
belongs_to :ownable, :polymorphic => true
end
end
With a migration that looks like this:
create_table :permissive_circles do |t|
t.string :ownable_type
t.integer :ownable_id
t.timestamps
end
The idea, of course, is that whatever loads acts_permissive will be able to have a list of circles that it owns.
For simple tests, I have
it "should have a list of circles" do
user = Factory :user
user.owned_circles.should be_an_instance_of Array
end
which fails with:
Failure/Error: #user.circles.should be_an_instance_of Array
NameError: uninitialized constant User::Ownable
I've tried: using :class_name => 'ActsPermissive::PermissiveCircle' on the has_many :ownables line, which fails with:
Failure/Error: #user.circles.should be_an_instance_of Array
ActiveRecord::HasManyThroughSourceAssociationNotFoundError:
Could not find the source association(s) :owned_circle or
:owned_circles in model ActsPermissive::PermissiveCircle.
Try 'has_many :owned_circles, :through => :ownables,
:source => <name>'. Is it one of :ownable?
while following the suggestion and setting :source => :ownable fails with
Failure/Error: #user.circles.should be_an_instance_of Array
ActiveRecord::HasManyThroughAssociationPolymorphicSourceError:
Cannot have a has_many :through association 'User#owned_circles'
on the polymorphic object 'Ownable#ownable'
Which seems to suggest that doing things with a non-polymorphic-through is necessary. So I added a circle_owner class similar to the setup here:
module ActsPermissive
class CircleOwner < ActiveRecord::Base
belongs_to :permissive_circle
belongs_to :ownable, :polymorphic => true
end
module PermissiveUser
def self.included(base)
base.extend ClassMethods
end
module ClassMethods
def acts_permissive
has_many :circle_owners, :as => :ownable
has_many :circles, :through => :circle_owners,
:source => :ownable,
:class_name => 'ActsPermissive::PermissiveCircle'
end
end
class PermissiveCircle < ActiveRecord::Base
has_many :circle_owners
end
end
With a migration:
create_table :permissive_circles do |t|
t.string :name
t.string :guid
t.timestamps
end
create_table :circle_owner do |t|
t.string :ownable_type
t.string :ownable_id
t.integer :permissive_circle_id
end
which still fails with:
Failure/Error: #user.circles.should be_an_instance_of Array
NameError:
uninitialized constant User::CircleOwner
Which brings us back to the beginning.
How can I do what seems to be a rather common polymorphic :has_many, :through on a module?
Alternatively, is there a good way to allow an object to be collected by arbitrary objects in a similar way that will work with a module?
It turns out that adding :class_name to both :has_many definitions will actually work (someone commented on that, but they deleted their comment). It didn't work in my non-simplified program because of something else in my program that was causing a cascading error that SEEMED to be local to the :has_many definition.
Short story: It was a lot of trouble for something that wasn't actually a problem. Blech
Let's say I have the following models:
Class Wishlist
belongs_to :user # User class is irrelevant here
has_many :inclusions
has_many :products, :through => :inclusions
end
Class Product
has_many :inclusions
has_many :wishlists, :through => :inclusions
end
Class Inclusion
belongs_to :product
belongs_to :wishlist
end
inclusions/index.html.erb
<%= render #inclusions %>
inclusions/_inclusion.html.erb
<%= "#{ inclusion.quantity } #{ inclusion.product.name } #{ inclusion.wishlist.user.name }"%>
This example is trivial, but the point is: the amount of database queries is overwhelming. For every instance of _inclusion.html.erb, at least three new queries seem to be created.
Is there a way to prefetch this information beforehand, maybe through a JOIN command?
Maybe this can help:
#inclusions = Inclusions.includes(:product, { :wishlist => :user })
Read about eager loading.
have you thinking about creating sql view, called for example ProductsWishlist and (if the performance will be bad) materializing it?
http://ss64.com/ora/syntax-views.html