Can you help me? I dont understand how to do it.
How to calculate TOTAL PRICE when i created the room?
I am dont understand how to do it right.
Here is my code:
room_controller.rb
def create
parameters = room_params.to_hash
parameters[:created_by] = #current_user.id
parameters[:account_id] = #current_user.account_id
#room = #section.rooms.create!(parameters)
update_room(#room, params)
end
...
def update
params = room_params.to_hash
update_room(#room, params)
json_response(#room)
end
def update_room(room, json)
return unless room
unless json.key?('total_price')
if json.key?('price') || json.key?('square')
square = json.key?('square') ? json['square'].to_f : room.square
price = json.key?('price') ? json['price'].to_f : room.price
json['total_price'] = price * square
end
end
unless json.key?('price')
if json.key?('total_price') || json.key?('square')
square = json.key?('square') ? json['square'].to_f : room.square
total_price = json.key?('total_price') ? json['total_price'].to_f : room.total_price
json['price'] = total_price / square
end
end
room.update(json)
end
def room_params
params.permit(
:level, :square, :total_price, :price, :number, :room_type,
:plan_image, :plan_coordinate, :view_image, :interior_image,
:rooms_count, :status, :marked
)
end
schema.rb
create_table "rooms", force: :cascade do |t|
...
t.float "square", default: 0.0
t.float "price", default: 0.0
t.float "total_price", default: 0.0
If total_price is square multiplied by price you can do that in the model.
class Room
before_save :calculate_total
private
def calculate_total
self.total_price = square * price
end
end
Related
To practice, I'm trying to create a small web game with Ruby On Rails, however, I need some information in my model and also in my controller.
I explain myself. For example, in my model, I have the following method:
def cost(building)
{
wood: BUILDING[building]['wood'] * (BUILDING[building]['factor'] ** self.level(building)),
stone: BUILDING[building]['stone'] * (BUILDING[building]['factor'] ** self.level(building)),
iron: BUILDING[building]['iron'] * (BUILDING[building]['factor'] ** self.level(building))
}
end
Then in my view I use the following to display the cost of upgrading the building :
<%= #buildings.cost(building[0])[:wood] %>
But I also have an "upgrade" button in my view that allows to upgrade this building, except that on the controller side I also need to get the costs of the building but I'm not sure of the right approach.
[EDIT] :
To give more informations :
#buildings = #buildings = Building.find_by(kingdom_id: current_kingdom.id) #Inside BuildingsController
building[0] It is a string in a yaml that corresponds to the name of a building
level it recovers the current level of the building for the player
EDIT 2 :
models/building.rb :
class Building < ApplicationRecord
def cost(building)
{
wood: BUILDING[building]['wood'] * (BUILDING[building]['factor'] ** self.level(building)),
stone: BUILDING[building]['stone'] * (BUILDING[building]['factor'] ** self.level(building)),
iron: BUILDING[building]['iron'] * (BUILDING[building]['factor'] ** self.level(building))
}
end
def consumption(building)
BUILDING[building]['coal']
end
def time(building)
resources_needed = cost(building)[:wood] + cost(building)[:stone] + cost(building)[:iron]
time = (resources_needed / (2500 * 4 * SERVER['rate']).to_f * 3600).round
if time >= 3600
"#{time / 60 / 60} h #{time % 3600 / 60} min"
elsif time >= 60
"#{time / 60} min #{time % 60 } sec"
else
"#{time} sec"
end
end
def level(building)
self[building.to_sym]
end
def upgrade?(building, kingdom_resources)
cost(building)[:wood] <= kingdom_resources[:wood] &&
cost(building)[:stone] <= kingdom_resources[:stone] &&
cost(building)[:iron] <= kingdom_resources[:iron]
end
end
buildings_controller.rb :
class BuildingsController < ApplicationController
def index
#buildings = Building.find_by(kingdom_id: current_kingdom.id)
#kingdom_resources = kingdom_resources
#kingdom_queue = BuildQueue.where(kingdom_id: current_kingdom.id)
end
def add_to_queue
building = params[:building]
# If we can upgrade
# Add building to the queue
end
private
def cost(building)
{
wood: BUILDING[building]['wood'] * (BUILDING[building]['factor'] ** self.level(building)),
stone: BUILDING[building]['stone'] * (BUILDING[building]['factor'] ** self.level(building)),
iron: BUILDING[building]['iron'] * (BUILDING[building]['factor'] ** self.level(building))
}
end
def building_level(building)
Building.find_by(kingdom_id: current_kingdom.id)[building.to_sym]
end
def time(building)
resources_needed = cost(building)[:wood] + cost(building)[:stone] + cost(building)[:iron]
(resources_needed / (2500 * 4 * SERVER['rate']).to_f * 3600).round
end
def upgrade?(building)
cost(building)[:wood] <= kingdom_resources[:wood] &&
cost(building)[:stone] <= kingdom_resources[:stone] &&
cost(building)[:iron] <= kingdom_resources[:iron]
end
end
method inside app/controllers/application_controller.rb,
To get the current_kingdom :
def current_kingdom
return nil unless current_user
return #_kingdom if #_kingdom
#_kingdom = Kingdom.find_by(user_id: current_user.id)
end
And current_user :
def current_user
return nil if !session[:auth] || !session[:auth]['id']
return #_user if #_user
#_user = User.find_by_id(session[:auth]['id'])
end
And current kingdom_resources :
def kingdom_resources
return #kingdom if #kingdom
#kingdom = {
wood: current_kingdom.wood,
stone: current_kingdom.stone,
iron: current_kingdom.iron,
coal: current_kingdom.coal,
food: current_kingdom.food
}
end
Thank's in advance,
Regards
fA user has a kingdom. A kingdom has buildings. We can set that up simple enough. A kingdom apparently also has build queues and resources.
class User < ApplicationRecord
has_one :kingdom
has_many :buildings, through: :kingdom
end
create_table :kingdoms do |t|
t.belongs_to :user, foreign_key: true
t.name :string, null: false
t.wood :integer, null: false
t.stone :integer, null: false
t.iron :integer, null: false
t.coal :integer, null: false
t.food :integer, null: false
end
class Kingdom < ApplicationRecord
belongs_to :user
has_many :buildings
has_many :build_queues
def resource(material)
self[material]
end
end
class BuildQueue < ApplicationRecord
belongs_to :kingdom
belongs_to :building
end
Now you can directly ask a player for its buildings: current_user.buildings and a kingdom for its build queues: kingdom.build_queues.
If you want to find a building by name: current_user.buildings.find_by(name: building_name).
Your Building model is strange. It seems like a single Building object represents all buildings. And information about the cost of a building is stored in a global.
Instead, the information about each building should instead be stored in a table row.
create_table :buildings do |t|
t.belongs_to :kingdom, foreign_key: true
t.string :name, null: false
t.cost_wood :integer, null: false
t.cost_stone :integer, null: false
t.cost_iron :integer, null: false
t.consumption_coal :integer, null: false
t.cost_factor :float, default: 1, null: false
t.level :integer, default: 1, null: false
end
class Building < ApplicationRecord
belongs_to :kingdom
has_one :player, through :kingdom
MATERIALS = [:wood, :stone, :iron].freeze
private def base_cost(material)
self[:"cost_#{material}"]
end
def cost(material)
base_cost(material) * cost_factor ** level
end
def build_cost
MATERIALS.sum { |m| cost(m) }
end
def build_time
# ActiveSupport::Duration will do the formatting for you.
ActiveSupport::Duration.build(
(build_cost / (2500 * 4 * SERVER['rate']).to_f * 3600).round
)
end
end
Now the BuildingsController can use what's been set up in the models.
class BuildingsController < ApplicationController
def index
# A user already has associations to its kingdom and buildings
# This is so simple there's no need for a current_kingdom in
# the ApplicationController
#kingdom = current_user.kingdom
#buildings = current_user.buildings
end
def show
if params[:id].present?
#building = current_user.buildings.find_by(id: params[:id])
else
#building = current_user.buildings.find_by(name: params[:name])
end
end
end
If you want to take action that involves multiple models, make a little object to do it. Like queuing a building upgrade.
# BuildingUpgradeQueuer.new(
# building: building,
# kingdom: kingdom
# ).queue_upgrade
class BuildingUpgradeQueuer
include ActiveModel::Model
MATERIALS = [:wood, :stone, :iron].freeze
attr_accessor :buiding, :kingdom
def queue_upgrade
return unless upgrade?
kingdom.build_queues.create!(building: building)
end
def upgrade?
MATERIALS.all? { |material|
building.cost(material) <= kingdom.resources(material)
}
end
end
You could do this in the Building or Kingdom object, but if you do that your models get complex and fat.
Hi Im creating an ec site in my rails.
My migration:
(Item) has :name and :price.
(Basket_Item) has :item_id(fk), :basket_id(fk) and :quantity.
The system User will add some items to their basket.
So Basket_items is JOIN Table between (Item) and (Basket)
see like below.
What I want to do:
Get a price of Item and get a quantity from Basket_Items which is selected by user. Then I want to create #total_price = item_price * item_quantity.
Can anyone help me to create the #total_price please.
This is my a try code but it doesn't work on rails console.
Basket_items
class CreateBasketItems < ActiveRecord::Migration[5.2]
def change
create_table :basket_items do |t|
t.references :basket, index: true, null: false, foreign_key: true
t.references :item, index: true, null: false, foreign_key: true
t.integer :quantity, null: false, default: 1
t.timestamps
end
end
end
///
Items
class CreateItems < ActiveRecord::Migration[5.2]
def change
create_table :items do |t|
t.references :admin, index: true, null: false, foreign_key: true
t.string :name, null: false, index: true
t.integer :price, null: false
t.text :message
t.string :category, index: true
t.string :img
t.string :Video_url
t.text :discription
t.timestamps
end
end
end
///
This is my try a code but it doesn't work on rails console.
basket = current_user.prepare_basket
item_ids = basket.basket_items.select(:item_id)
items = basket.items.where(id: item_ids)
items_price = items.select(:price)
items_quantity = basket.basket_items.where(item_id: item_ids).pluck(:quantity)
def self.total(items_price, items_quantity)
sum(items_price * items_quantity)
end
#total_price = basket.total(items_price, item_quantity)
There are a few issues with your code:
You are trying to call a class method on an instance of the class. That's not gonna work, second you are passing in arrays into the calculation.
basket = current_user.prepare_basket
item_ids = basket.basket_items.select(:item_id)
items = basket.items.where(id: item_ids)
items_price = items.select(:price) # => Array of prices from the items in the basket
items_quantity = basket.basket_items.where(item_id: item_ids).pluck(:quantity) # => Array of quantities from the items in the basket
def self.total(items_price, items_quantity)
sum(items_price * items_quantity) # => So this line will do: sum(['12,95', '9.99'] * [1, 3])
end
#total_price = basket.total(items_price, item_quantity)
As you can see, that ain't gonna work. First you need to change the method and remove the self.
def total(items_price, items_quantity)
# ...
end
Now you can call the total method on a basket object: basket.total(items_price, items_quantity)
And inside the total method you need to loop through each items to do the calculation and add all the results.
def total(items_price, items_quantity)
total_price = 0
items_price.each_with_index do |price, index|
total_price += price * items_quantity[index]
end
total_price
end
But this solution could also fail, because you don't know sure that the order in the items_price is matching with the order of items_quantity. So a better approach would be to do the calculation for each basket_item seperate.
# Basket model
def total
total_price = 0
basket_items.each do |basket_item|
total_price += basket_item.total_price
end
total_price
end
# BasketItem model
def total_price
quantity * item.price
end
Now you can call it like this: basket.total
Rails version: 5.2.2.1
DB
db/migrate/20190520050333_create_posts.rb
class CreatePosts < ActiveRecord::Migration[5.2]
def change
create_table :posts do |t|
t.string :title
t.text :body
t.timestamps
end
end
end
db/migrate/20190520050350_create_post_copies.rb
class CreatePostCopies < ActiveRecord::Migration[5.2]
def change
create_table :post_copies do |t|
t.string :title
t.text :body
t.timestamps
end
end
end
Model
app/models/post.rb
class Post < ApplicationRecord
after_save :save_post_copy
private
def save_post_copy
if title_changed?
post_copy = PostCopy.new
post_copy.id = self.id
post_copy.title = self.title
post_copy.body = self.body
post_copy.save!
end
end
end
Console
post = Post.first
post.title = 'change title'
post.title_changed? # => true
post.save!
PostCopy.first
=> nil
Here want to auto save the record to post_copies when the title been changed in posts. But after the record saved in posts, can't find anything in post_copies.
Probably id should not be explicitly set, as rails automatically assign the value of the id
def save_post_copy
if self.title_changed?
post_copy = PostCopy.new
#post_copy.id = self.id
post_copy.title = self.title
post_copy.body = self.body
post_copy.save!
end
end
Or alternatively
after_save :save_post_copy, if: : saved_change_to_title
def save_post_copy
post_copy = PostCopy.new
post_copy = self.dup
post_copy.save
end
I'm building an Events app in Rails and I've hit the error above which relates to this method in my Model -
def validate_availability
errors.add(:base, 'event is fully booked') if booking.count >= event.number_of_spaces
end
The purpose of the method is to avoid over-booking of an event whereby a specific number of spaces are available. In my Controller I have the following code -
Controller#Create
def create
#event = Event.find(params[:event_id])
#booking = #event.bookings.new(booking_params)
#booking.user = current_user
if
#booking.set_booking
flash[:success] = "Your place on our event has been booked"
redirect_to event_booking_path(#event, #booking)
else
flash[:error] = "Booking unsuccessful"
render "new"
end
if #event.is_free?
#booking.save(booking_params)
end
if booking.count >= #event.number_of_spaces
flash[:error] = "Sorry, this event is now fully booked"
render "new"
end
end
I need to define booking.count in my controller but not sure what would work - tried a few things but nothings working. I have the following in my schema -
create_table "bookings", force: :cascade do |t|
t.integer "event_id"
t.integer "user_id"
t.string "stripe_token"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.integer "quantity", default: 1
t.integer "total_amount"
t.string "stripe_charge_id"
t.string "booking_number"
end
The booking.count would rely upon the quantity of spaces/bookings a user wishes to make versus the number of spaces remaining but how do I express this? Do I need a total_bookings column in my table or a separate method?
UPDATE -
Booking.rb
class Booking < ActiveRecord::Base
belongs_to :event
belongs_to :user
before_create :set_booking_number
validates :quantity, presence: true, numericality: { greater_than_or_equal_to: 0 }
validates :total_amount, presence: true, numericality: { greater_than_or_equal_to: 0 }
validate(:validate_booking)
validate(:validate_availability)
def set_booking_number
self.booking_number = "MAMA" + '- ' + SecureRandom.hex(4).upcase
end
def set_booking
if self.event.is_free?
self.total_amount = 0
save!
else
self.total_amount = event.price_pennies * self.quantity
begin
charge = Stripe::Charge.create(
amount: total_amount,
currency: "gbp",
source: stripe_token,
description: "Booking created for amount #{total_amount}")
self.stripe_charge_id = charge.id
save!
rescue Stripe::CardError => e
# if this fails stripe_charge_id will be null, but in case of update we just set it to nil again
self.stripe_charge_id = nil
# we check in validatition if nil
end
end
end
def validate_booking
# stripe_charge_id must be set for not free events
unless self.event.is_free?
return !self.stripe_charge_id.nil?
end
end
private
def validate_availability
errors.add(:base, 'event is fully booked') if event.bookings.count >= event.number_of_spaces
end
end
For the counts of booking table, you should have a booking_count field in events table. Use the counter cache for this. For more details check http://guides.rubyonrails.org/association_basics.html. This is very helpful when records are large.
Your migration for adding column should be similar as below:
def change
add_column :events, :bookings_count, :integer, default: 0
Event.reset_column_information
Event.all.each do |e|
Event.update_counters e.id, :bookings_count => e.bookings.length
end
end
If i change the processing from client-side to server-side, i will get all information for the table, but I can't search and sort the columns. But its possible to go to the next page. I have only 2 columns for searching and sorting to test it. Hopefully you can help me.
Database:
t.text "comment"
t.datetime "created_at", :null => false
t.datetime "updated_at", :null => false
t.integer "source_stock_id"
t.integer "destination_stock_id"
t.integer "order_id"
js.coffee-Code:
jQuery ->
$("#product_relocates_table").dataTable
bProcessing: true
bServerSide: true
sAjaxSource: $('#product_relocates_table').data('source')
"aaSorting": [[ 0, "desc" ]]
Datatable-Code:
class ProductRelocatesDatatable
delegate :params, :h, :link_to, to: :#view
def initialize(view)
#view = view
end
def as_json(options = {})
{
sEcho: params[:sEcho].to_i,
iTotalRecords: ProductRelocate.count,
iTotalDisplayRecords: product_relocates.total_count,
aaData: data
}
end
private
def data
product_relocates.map do |product_relocate|
[
h(product_relocate.created_at),
h(product_relocate.comment),
h(product_relocate.source_stock),
h(product_relocate.destination_stock),
h(product_relocate.quantity),
link_to('Show', [:admin, product_relocate])
]
end
end
def product_relocates
#product_relocates ||= fetch_product_relocates
end
def fetch_product_relocates
product_relocates = ProductRelocate.order("#{sort_column} #{sort_direction}")
product_relocates = product_relocates.page(page).per(per)
if params[:sSearch].present?
search_string = search_columns.map do |search_column|
"#{search_column} like :search"
end.join(" OR ")
product_relocates = product_relocates.where(search_string, search: "%#{params[:sSearch]}%")
end
product_relocates
end
def page
params[:iDisplayStart].to_i/per + 1
end
def per
params[:iDisplayLength].to_i > 0 ? params[:iDisplayLength].to_i : 10
end
def search_columns
%w[product_relocates.created_at product_relocates.comment]
end
def sort_columns
%w[product_relocates.created_at product_relocates.comment]
end
def sort_column
sort_columns[params[:iSortCol_0].to_i]
end
def sort_direction
params[:sSortDir_0] == "desc" ? "desc" : "asc"
end
end
I refactored a superclass that handles server side multi-column searching and sorting:
https://gist.github.com/2936095
which is derived from:
http://railscasts.com/episodes/340-datatables
class Datatable
delegate :params, :h, :raw, :link_to, :number_to_currency, to: :#view
def initialize(klass,view)
#klass = klass
#view = view
end
def as_json(options = {})
{
sEcho: params[:sEcho].to_i,
iTotalRecords: #klass.count,
iTotalDisplayRecords: items.total_entries,
aaData: data
}
end
private
def data
[]
end
def items
#items ||= fetch_items
end
def fetch_items
items = filtered_list
items = selected_columns(items)
items = items.order(sort_order)
items = items.page(page).per_page(per_page)
if params[:sSearch].present?
items = items.where(quick_search)
end
items
end
def filtered_list
#klass.all
end
def selected_columns items
items
end
def quick_search
search_for = params[:sSearch].split(' ')
terms = {}
which_one = -1
criteria = search_for.inject([]) do |criteria,atom|
which_one += 1
terms["search#{which_one}".to_sym] = "%#{atom}%"
criteria << "(#{search_cols.map{|col| "#{col} like :search#{which_one}"}.join(' or ')})"
end.join(' and ')
[criteria, terms]
end
def page
params[:iDisplayStart].to_i/per_page + 1
end
def per_page
params[:iDisplayLength].to_i > 0 ? params[:iDisplayLength].to_i : 10
end
def columns
[]
end
def sort_order
colnum = 0
sort_by = []
while true
break if !sorted?(colnum)
sort_by << "#{sort_column(colnum)} #{sort_direction(colnum)}"
colnum += 1
end
sort_by.join(", ")
end
def sorted? index=0
!params["iSortCol_#{index}"].nil?
end
def sort_column index=0
index = "iSortCol_#{index}"
columns[params[index].to_i]
end
def sort_direction index=0
index = "sSortDir_#{index}"
params[index] == "desc" ? "desc" : "asc"
end
end