Rails many to many token fields help - ruby-on-rails

I am having that problem that my model dont want to save. I have a token field input for tags.
I have followed this guide for the token input: http://railscasts.com/episodes/258-token-fields
I get this error when I try to create a new konkurrancer:
NoMethodError in Admin/konkurrancersController#create
undefined method `class_name' for nil:NilClass
Rails.root: C:/Rails/konkurranceportalen
Application Trace | Framework Trace | Full Trace
app/models/konkurrancer.rb:15:in `tag_tokens='
app/controllers/admin/konkurrancers_controller.rb:48:in `new'
app/controllers/admin/konkurrancers_controller.rb:48:in `create'
http://pastie.org/1834194
Request
Parameters:
{"utf8"=>"✓",
"authenticity_token"=>"yo7wcAQl81tx3zZpPP44ENPYzYRZLpgyYKY+HK3yFKM=",
"konkurrancer"=>{"name"=>"Vind en rejse",
"banner2"=>"asdasd",
"tracking"=>"sadasd",
"vaerdi"=>"12222",
"tid"=>"1 min",
"tag_tokens"=>"1",
"bedom"=>"2",
"kategori_id"=>"9",
"form"=>"Nyhedsbrev",
"partner"=>"Iqmedier",
"udtraekkes(3i)"=>"30",
"udtraekkes(2i)"=>"4",
"udtraekkes(1i)"=>"2011",
"udtraekkes(4i)"=>"08",
"udtraekkes(5i)"=>"26",
"arrangeor"=>"",
"note"=>""},
"commit"=>"Opret konkurrence"}
My konkurrancer model:
class Konkurrancer < ActiveRecord::Base
attr_accessible :name, :tag_tokens
has_many :tagsmenus
has_many :tags, :through => :tagsmenus
attr_reader :tag_tokens
def tag_tokens=(ids)
self.tag_ids = ids.split(",")
end
end
My tag model:
class Tag < ActiveRecord::Base
has_many :tagsmenus
has_many :konkurrancers, :through => :tagsmenus
has_friendly_id :name, :use_slug => true
before_save :assign_cached_slug, :unless => :cached_slug?
protected
def assign_cached_slug
self.cached_slug = self.name.gsub(/\s+/, '_').gsub(/[^\w\-]/, '')
end
end
My tagmenu model:
class Tagsmenu < ActiveRecord::Base
end
My controller:
def new
#konkurrancer = Konkurrancer.new
respond_to do |format|
format.html # new.html.erb
format.xml { render :xml => #konkurrancer }
end
end
# POST /konkurrancers
# POST /konkurrancers.xml
def create
#konkurrancer = Konkurrancer.new(params[:konkurrancer])
respond_to do |format|
if #konkurrancer.save
format.html { redirect_to(:admin_konkurrancers, :notice => 'Konkurrancer was successfully created.') }
format.xml { render :xml => :admin_konkurrancers, :status => :created, :location => #konkurrancer }
else
format.html { render :action => "new" }
format.xml { render :xml => #konkurrancer.errors, :status => :unprocessable_entity }
end
end
end
I have created the join table and the model and also added the relation to my tag model.

Your model has some conflicting statements. You first define:
attr_accessor ... :tag_tokens
then later have:
attr_reader :tag_tokens
which is not necessary given the first line or vice versa given that later you have a deinition for the setter:
def tag_tokens(ids)
self.tag_ids = ids.split(',')
end
I don't see tag_ids defined either given it is not a column in your table. You should probably remove the attr_accessor definition for the tag_tokens and then define the tag_ids method for starters.

class Tagsmenu < ActiveRecord::Base
belongs_to :konkurrancer
belongs_to :tag
end

Related

Rails behaving strange

I have rails version 3.2.13 and ruby version 1.9.3.
I have caught into very strange and interesting situation.
In my application have a model 'Product' with custom validator.
product.rb
class Product < ActiveRecord::Base
attr_accessible :description, :name, :price, :short_description, :user_id
validates :name, :short_description, presence: true
validates :price, :numericality => {:greater_than_or_equal_to => 0}
validate :uniq_name
belongs_to :user
belongs_to :original, foreign_key: :copied_from_id, class_name: 'Product'
has_many :clones, foreign_key: :copied_from_id, class_name: 'Product', dependent: :nullify
def clone?
self.original ? true : false
end
private
#Custom validator
def uniq_name
return if clone?
user_product = self.user.products.unlocked.where(:name => self.name).first
errors[:name] << "has already been taken" if user_product && !user_product.id.eql?(self.id)
end
end
In products controller's create action when I am trying to create new product
def create
#product = current_user.products.new(params[:product])
respond_to do |format|
if #product.save
format.html { redirect_to #product, notice: 'Product was successfully created.' }
format.json { render json: #product, status: :created, location: #product }
else
#product.errors[:image] = "Invalid file extension" if #product.errors[:image_content_type].present?
format.html { render action: "new" }
format.json { render json: #product.errors, status: :unprocessable_entity }
end
end
end
Custom validator is being called when this line executed #product = current_user.products.new(params[:product]) and line # 2 of custom validator giving me error
undefined method `products' for nil:NilClass
I have inspected product object in custom validator but user_id is nil.
Why user_id is not being autoassigned?
Your help will be appreciated :)
So ... bypassing your question. Why aren't you just validating the uniqueness of name?
validates_uniqueness_of :name, :unless => :clone?
try to change .new to .build
#product = current_user.products.build(params[:product])
and be sure that you have relation in your User model
Class User < ActiveRecord::Base
has_many :products

Ruby On Rails Pagination and delete :through association

I am running into a strange situation, considering the following models:
class Collection < ActiveRecord::Base
attr_accessible :name, :season, :year
has_many :collection_items_assocs
has_many :items, :through => :collection_items_assocs
end
class Item < ActiveRecord::Base
attr_accessible :name, :reference, :item_type_id
has_many :pictures
has_one :item_type
end
class CollectionItemsAssoc < ActiveRecord::Base
attr_accessible :collection_id, :item_id
belongs_to :item
belongs_to :collection
end
I can successfully retrieve Items associated to a Collection with the following code:
# GET /collections/1
# GET /collections/1.json
def show
#collection = Collection.find(params[:id])
#collection.items = Collection.find(params[:id]).items
respond_to do |format|
format.json { render json: #collection.to_json(:include => {:items => #collection}) }
end
end
But when I try to include pagination (for items) like that
# GET /collections/1
# GET /collections/1.json
def show
#collection = Collection.find(params[:id])
**#collection.items = Collection.find(params[:id]).items.paginate(:page => params[:page],:per_page =>1)**
respond_to do |format|
format.json { render json: #collection.to_json(:include => {:items => #collection}) }
end
end
It works for the following call
/retailapp/collections/1?format=json&**page=1**
Then if I call
/retailapp/collections/1?format=json&**page=2**
the records in the association table CollectionItemsAssoc are deleted
I really don't get it
Thanks for your help
The problem is the code to fetch the items
#collection.items = Collection.find(params[:id]).items
it assigned the fetched items to current collection object.
you need to change the response to support the pagination on associate objects
  def show
   #collection = Collection.find(params[:id])
respond_to do |format|
format.json {
json_hash = #collection.as_json
json_hash[:items] = #collection.items.paginate(:page => params[:page],:per_page =>1).as_json
render json: json_hash.to_json
}
end
Additionally you can overwrite to_json method inside Collection model.

Rails Active Record Query and JSON

I have the following models in my Rails application:
class Transaction
belongs_to :category
has_one :group, :through => :category
class Category
belongs_to :group
has_many :transactions
class Group
has_many :categories
has_many :transactions, :through => :category
In my controller is the following:
#transactions = Transaction.includes(:category, :group).group("groups.id").sum("amount")
respond_to do |format|
format.json{
render :json => JSON.generate(#transactions.as_json(:include => [:category, :group]))
}
end
This produces the following json (A):
{"1":2000,"3":5000,"2":1000}
However, my goal is to produce something like this (B):
[{"group_id":1,"amount":2000},{"group_id":3,"amount":5000},{"group_id":2,"amount":1000}]
Any help on how I can go from A to B would be greatly appreciated.
Try:
def user_transactions
#transactions = Transaction.includes(:category, :group).group("groups.id").sum("amount")
respond_to do |format|
format.html
format.json do
render :json => custom_json_for(#transactions)
end
end
end
private
def custom_json_for(value)
list = value.map do |k,v|
{ :group_id => k,
:amount=> v
}
end
list.to_json
end
If you're doing a lot a JSON-serialization, I would recommend you to take a look at ActiveModelSerializers:
https://github.com/rails-api/active_model_serializers

Rails: am I nesting incorrectly?

Hi I'm currently working on my first project, and am trying to build the functionality first before doing the login/sessions. I'm trying to create a picture album website, where users have many albums (that contain many pictures), and album access is shared among friends. However, I'm noticing that after my albums#create
http://localhost:3000/users/18/albums/new (no problem here)
I am redirected to albums#show:
http://localhost:3000/albums/20 (problem!!)
shouldn't there be a user_id in the URL as well?? Or does it not have a user_id attached to the URL because it belongs to multiple users? Here are my routes:
Pholder::Application.routes.draw do
resources :users do
resources :albums
end
resources :albums do
resources :pictures
end
root :to => "users#index"
Here are my models in case:
user model
class User < ActiveRecord::Base
has_secure_password
attr_accessible :email, :name, :password, :password_confirmation
validates_presence_of :password, :on => :create
validates_format_of :name, :with => /[A-Za-z]+/, :on => :create
validates_format_of :email, :with => /\A([^#\s]+)#((?:[-a-z0-9]+\.)+[a-z]{2,})\Z/i, :on => :create
validates_length_of :password, :minimum => 5, :on => :create
has_many :user_albums
has_many :albums, :through => :user_albums
accepts_nested_attributes_for :albums
end
album model
class Album < ActiveRecord::Base
attr_accessible :avatar, :name, :description
has_many :user_albums
has_many :users, :through => :user_albums
has_many :photos
end
photo album
class Photo < ActiveRecord::Base
belongs_to :album
end
albums controller
class AlbumsController < ApplicationController
def index
#albums = Albums.all
respond_to do |format|
format.html
format.json { render json: #albums }
end
end
def show
#albums = Album.all
#album = Album.find(params[:id])
#photo = Photo.new
end
def update
end
def edit
end
def create
# #user = User.find(params[:albums][:user_id])
# #users = User.all
#album = Album.new(params[:album])
# #album.user_id = #user.id
respond_to do |format|
if #album.save
format.html { redirect_to #album, notice: 'Album was successfully created.' }
format.json { render json: #album, status: :created, location: #album}
else
format.html { render action: "new" }
format.json { render json: #album.errors, status: :unprocessable_entity }
end
end
end
def new
#user = User.find(params[:user_id])
#album = Album.new
end
def destroy
end
end
Let me know if you need any other files.
The line redirect_to #album makes you redirect to the show action of the #album in question.
Changing this piece of code to something like redirect_to users_path will make the app redirect to the index action of users_controller and so on.
It depends on whatever behavior you want after the save.
Reading this should be helpful too: http://guides.rubyonrails.org/routing.html

Filter on "include" - Rails 3

these are my associations:
class Activity < ActiveRecord::Base
has_many :infos, :dependent => :destroy
has_many :events, :dependent => :destroy
accepts_nested_attributes_for :infos
end
class Event < ActiveRecord::Base
belongs_to :activity
has_many :infos, :through => :activity
end
class Info < ActiveRecord::Base
has_one :language
belongs_to :activity
end
Now i can get an XML with all the events and their infos using:
#events = Event.all
respond_to do |format|
format.xml { render :xml => #events.to_xml(:include => [:infos ]) }
end
The problem is that i get the infos from all the language.
Is it possible to use a filter (as "where info.language.id==1"), so that only the language1 infos are displayed in the XML for each event?
Thanks
UPDATE :
Hi Mike, thanks for your answer.
Unfortunately i'm getting this error:
undefined method `eq' for nil:NilClass
Rails.root: /Users/abramo/village
Application Trace | Framework Trace |
Full Trace
app/controllers/events_controller.rb:29:in
block (2 levels) in locale'
app/controllers/events_controller.rb:28:in
locale'
and lines 28,29 are the last line of my locale method:
def locale
#events = Event.joins(:infos => :language).where("languages.id = 2")
respond_to do |format|
format.xml { render :xml => #events.to_xml(:include => [:infos ]) }
end
end
I really don't understand... what object is Nil?
Event.joins(:infos => :language).where("languages.id = 1")

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