I'm using Rails, but the underlying question here applies more broadly. I have a report page on my web app that allows the user to specify what they're filtering on, and query the database based on those filters (MongoDB).
The data is based around hotels, the user must first select the regions of the hotels (state_one, state_two, state_three), then the statuses of the hotels (planning, under_construction, operational), then an optional criteria, price range (200, 300, 400). Users can select multiple of each of these options.
My way of doing this currently is to create an empty array, iterate through each region, and push the region into the array if the user selected that region. Then, I'm iterating through THAT array, and assessing the status of the hotels in those regions, if any hotel has the status the user has selected, then I'm adding that hotel to a new empty array. Then I do the same thing for price range.
This works, but the code is offensively messy, here's an example of the code:
def find_hotel
hotels = find_all_hotels
first_array = []
hotels.each do |hotel|
if params[:options][:region].include? 'state_one' and hotel.state == :one
first_array.push(hotel)
elsif params[:options][:region].include? 'state_two' and hotel.state == :two
first_array.push(hotel)
elsif params[:options][:region].include? 'state_three' and hotel.state == :three
first_array.push(hotel)
end
end
second_array = []
first_array.each do |hotel|
if params[:options][:region].include? 'planning' and hotel.status == :planning
first_array.push(hotel)
elsif params[:options][:region].include? 'under_construction' and hotel.status == :under_construction
first_array.push(hotel)
elsif params[:options][:region].include? 'operational' and hotel.status == :operational
first_array.push(hotel)
end
end
third_array = []
second_array.each do |hotel|
# More of the same here, this could go on forever
end
end
What are some better ways of achieving this?
How about this:
STATES = [:one, :two, :three]
STATUSES = [:planning, :under_construction, :operational]
PRICES = [200, 300, 400]
def find_hotel
region = params[:options][:region]
first_array = set_array(region, find_all_hotels, STATES, :state)
second_array = set_array(region, first_array, STATUSES, :status)
third_array = set_array(region, second_array, PRICES, :price_range)
end
def set_array(region, array, options, attribute)
array.each_with_object([]) do |element, result|
options.each do |option|
result << element if region.include?(option) && element[attribute] == option
end
end
end
UPDATE
Added attribute parameter to set_array in order to make the code work with your updated example.
Since second_array is empty, whatever you get by iterating over it (perhaps third_array) would also be empty.
def find_hotel
hotels = find_all_hotels
first_array = hotels
.select{|hotel| params[:options][:region].include?("state_#{hotel.state}")}
first_array += first_array
.select{|hotel| params[:options][:region].include?(hotel.status.to_s)}
second_array = third_array = []
...
end
Related
For this particular use case I have a method that gets all the sales opportunities for a user, for the inventory he has in stock. It's a loop that goes through the user's parts and then checks each part against the "reverse-auction" to make sure the auction is an opportunity and if it is, stick it in this array 'sales_opportunities'
So, in my Auction model I have the method:
def self.get_sales_opportunities(user)
parts = user.inventory_parts
parts.uniq! { |part| [part[:part_num], part[:condition]] }
sales_opportunities = []
parts.each do |part|
#stick auction in sales opportunities
#if the auction is not the user's, already contains a user bid,
#or if the auction isn't asking for the part in-question's condition
Auction.where(part_num: part.part_num, active: true).each do |auction|
user_created_auction = (auction.company == user)
user_has_placed_bids = (auction.bids & user.bids).present?
part_matches = auction.condition.include?(part.condition)
all_conditions = true if auction.condition[0].blank?
sales_opportunities << auction unless user_created_auction || user_has_placed_bids || !part_matches
sales_opportunities << auction if all_conditions && auction.company != user && !user_has_placed_bids
end
end
sales_opportunities.uniq
end
This is obviously a process and the load time is terrible..
How can I do this more efficiently?
I'm doing checks for empty parameters before do the query.
There is only 1 check for params[:car_model_id]. I can imagine if I will add more checks for other params, then there will be a mess of if-else statements. It doesn't look nice and I think it can be optimized. But how? Here is the code of controller:
class CarsController < ApplicationController
def search
if params[:car_model_id].empty?
#cars = Car.where(
used: ActiveRecord::Type::Boolean.new.cast(params[:used]),
year: params[:year_from]..params[:year_to],
price: params[:price_from]..params[:price_to],
condition: params[:condition]
)
else
#cars = Car.where(
used: ActiveRecord::Type::Boolean.new.cast(params[:used]),
car_model_id: params[:car_model_id],
year: params[:year_from]..params[:year_to],
price: params[:price_from]..params[:price_to],
condition: params[:condition]
)
end
if #cars
render json: #cars
else
render json: #cars.errors, status: :unprocessable_entity
end
end
end
The trick would be to remove the blank values, do a little bit of pre-processing (and possibly validation) of the data, and then pass the params to the where clause.
To help with the processing of the date ranges, you can create a method that checks both dates are provided and are converted to a range:
def convert_to_range(start_date, end_date)
if start_date && end_date
price_from = Date.parse(price_from)
price_to = Date.parse(price_to)
price_from..price_to
end
rescue ArgumentError => e
# If you're code reaches here then the user has invalid date and you
# need to work out how to handle this.
end
Then your controller action could look something like this:
# select only the params that are need
car_params = params.slice(:car_model_id, :used, :year_from, :year_to, :price_from, :price_to, :condition)
# do some processing of the data
year_from = car_params.delete(:year_from).presence
year_to = car_params.delete(:year_to).presence
car_params[:price] = convert_to_range(year_from, year_to)
price_from = car_params.delete(:price_from).presence
price_to = car_params.delete(:price_to).presence
car_params[:price] = convert_to_range(price_from, price_to)
# select only params that are present
car_params = car_params.select {|k, v| v.present? }
# search for the cars
#cars = Car.where(car_params)
Also, I'm pretty sure that the used value will automatically get cast to boolean for you when its provided to the where.
Also, #cars is an ActiveRecord::Relation which does not have an errors method. Perhaps you mean to give different results based on whether there are any cars returned?
E.g: #cars.any? (or #cars.load.any? if you don't want to execute two queries to fetch the cars and check if cars exist)
Edit:
As mentioned by mu is too short you can also clean up your code by chaining where conditions and scopes. Scopes help to move functionality out of the controller and into the model which increases re-usability of functionality.
E.g.
class Car > ActiveRecord::Base
scope :year_between, ->(from, to) { where(year: from..to) }
scope :price_between, ->(from, to) { where(price: from..to) }
scope :used, ->(value = true) { where(used: used) }
end
Then in your controller:
# initial condition is all cars
cars = Cars.all
# refine results with params provided by user
cars = cars.where(car_model_id: params[:car_model_id]) if params[:car_model_id].present?
cars = cars.year_between(params[:year_from], params[:year_to])
cars = cars.price_between(params[:price_from], params[:price_to])
cars = cars.used(params[:used])
cars = cars.where(condition: params[:condition]) if params[:condition].present?
#cars = cars
I want to pull data for each of my users. I grab their person_id from my user table, then use each person's ID to figure out how many days each person has available, and show that in my view.
I'm not sure if I am doing this correctly because I am iterating in my controller then again in my view.
def how_many_days_users_have
#my_group = User.all.pluck(:person_id)
#my_group.each do |v|
#indirect_id_v = Empaccrl.where("person_id = ? and is_active = ?", '#{v]', 'Y').pluck(:a_code).first
#v_range = Empaccrl.where("person_id = ? and is_active = ?", '#{v]', 'Y').pluck(:ac).first
#v_range_taken = Empaccrl.where("person_id = ? and is_active = ?", '#{v]', 'Y').pluck(:taken).first
#total_v_hours = #v_range.to_d - #v_range_taken.to_d
#total_v_days = #total_v_hours / 8
end
Then in my view I use this to show me this data:
%tr.trace-table
-#indirect_id_v.each do |idd|
%tr.trace-table
%td.trace-table{:style => 'border: solid black;'}= idd
-#total_v_days.each do |days|
%tr.trace-table
%td.trace-table{:style => 'border: solid black;'}= days
Okay, first things first, move some of that junk to your model, like so:
class Empaccrl < ActiveRecord::Base
def self.all_people
where(person_id: User.all.pluck(:person_id))
end
def self.active_people
all_people.where(is_active: 'Y')
end
def self.active_vacation_data
active_people.select(:person_id, :ac, :taken)
end
def total_v_hours
ac.to_d - taken.to_d
end
def total_v_days
total_v_hours / 8
end
end
Then you can use:
peoples_vacation_information = Empaccrl.active_vacation_data.all
peoples_vacation_information.map do |person|
p "person #{person.person_id} has #{person.total_v_days} vacation days"
end
Honestly, you don't even need all that, but I'm not sure why you are doing what you are doing, so I figured better be safe and add stuff. Whatever you don't need, just ignore.
A little bit of background:
Every product has a set of variants, the amount of variants a product has should change depending on its attributes.
A method called find_valid_variants returns the variants that the product should have, this is then passed to the destroy_redundant_variants method which is supposed to destroy any variants that the product has but are not included in the valid_variants.
def self.find_valid_variants(product)
product.product_options.blank? ? options = [nil] : options = product.product_options
product.product_sides.blank? ? sides = [nil] : sides = product.product_sides
product.product_sizes.blank? ? sizes = [nil] : sizes = product.product_sizes
valid_variants = []
sides.product(sizes, options).each do |side, size, option|
valid_variants << Variant.where(product_id: product.id, product_side_id: side, product_size_id: size, product_option_id: option)
end
valid_variants
end
def self.find_redundant_variants(product)
destroy_redundant_variants(product, find_valid_variants(product))
end
def self.destroy_redundant_variants(product, valid_variants)
(product.variants - valid_variants).each { |valid_variant| valid_variant.destroy }
end
The problem is that the method destroys all of the products variants when in my test case it should only destroy 2.
Here is the Rspec test:
it "destroys the redundant variants" do
#product = Fabricate(:product, product_size_ids: ["#{#product_size.id}", "#{#product_size_2.id}"], product_options_attributes: [{name: 'Rounded', description: 'Add a round edge'}, {name: 'None', description: 'Nothing'}])
#product.variants.count.should == 4
#product.product_options.each { |p| p.destroy }
#product.reload
ProductVariationService.find_redundant_variants(#product)
#product.variants.count.should == 2
end
In my Rails 3.2 app a Connector has_many Incidents.
To get all incidents of a certain connector I can do this:
(In console)
c = Connector.find(1) # c.class is Connector(id: integer, name: string, ...
i = c.incidents.all # all good, lists incidents of c
But how can I get all incidents of many connectors?
c = Connector.find(1,2) # works fine, but c.class is Array
i = c.incidents.all #=> NoMethodError: undefined method `incidents' for #<Array:0x4cc15e0>
Should be easy! But I don't get it!
Here’s the complete code in my statistics_controller.rb
class StatisticsController < ApplicationController
def index
#connectors = Connector.scoped
if params['connector_tokens']
logger.debug "Following tokens are given: #{params['connector_tokens']}"
#connectors = #connectors.find_all_by_name(params[:connector_tokens].split(','))
end
#start_at = params[:start_at] || 4.weeks.ago.beginning_of_week
#end_at = params[:end_at] || Time.now
##time_line_data = Incident.time_line_data( #start_at, #end_at, 10) #=> That works, but doesn’t limit the result to given connectors
#time_line_data = #connectors.incidents.time_line_data( #start_at, #end_at, 10) #=> undefined method `incidents' for #<ActiveRecord::Relation:0x3f643c8>
respond_to do |format|
format.html # index.html.haml
end
end
end
Edit with reference to first 3 answers below:
Great! With code below I get an array with all incidents of given connectors.
c = Connector.find(1,2)
i = c.map(&:incidents.all).flatten
But idealy I'd like to get an Active Records object instead of the array, because I'd like to call where() on it as you can see in methode time_line_data below.
I could reach my goal with the array, but I would need to change the whole strategy...
This is my time_line_data() in Incidents Model models/incidents.rb
def self.time_line_data(start_at = 8.weeks.ago, end_at = Time.now, lim = 10)
total = {}
rickshaw = []
arr = []
inc = where(created_at: start_at.to_time.beginning_of_day..end_at.to_time.end_of_day)
# create a hash, number of incidents per day, with day as key
inc.each do |i|
if total[i.created_at.to_date].to_i > 0
total[i.created_at.to_date] += 1
else
total[i.created_at.to_date] = 1
end
end
# create a hash with all days in given timeframe, number of incidents per day, date as key and 0 as value if no incident is in database for this day
(start_at.to_date..end_at.to_date).each do |date|
js_timestamp = date.to_time.to_i
if total[date].to_i > 0
arr.push([js_timestamp, total[date]])
rickshaw.push({x: js_timestamp, y: total[date]})
else
arr.push([js_timestamp, 0])
rickshaw.push({x: js_timestamp, y: 0})
end
end
{ :start_at => start_at,
:end_at => end_at,
:series => rickshaw #arr
}
end
As you only seem to be interested in the time line data you can further expand the map examples given before e.g.:
#time_line_data = #connectors.map do |connector|
connector.incidents.map do |incident|
incident.time_line_data(#start_at, #end_at, 10)
end
end
This will map/collect all the return values of the time_line_data method call on all the incidents in the collection of connectors.
Ref:- map
c = Connector.find(1,2)
i = c.map(&:incidents.all).flatten