I am working using rails and I have a class from activerecord called Car. In the application that I am building,The application let's the user add a new car in one the pages or if not they can choose the one that it's already there.
I am having difficulties trying to come up with a solution, although both of them work it would only execute until some part of code because it's in an if/else statement.
ad_group_controllers.rb
if params[:ad_group][:file]
#car = Car.create(year: params[:ad_group][:car][:year],model: params[:model],make_id: params[:make], trim: params[:trim])
#car.update(file: params[:ad_group][:file])
#ad_group.car = #car
else
#car = Car.find(params[:ad_group][:car][:id])
#trim = params[:trim] == 'none' ? nil : params[:trim]
#promotional_logo = params[:promotional_logo].blank? || params[:promotional_logo].downcase == 'none' || params[:promotional_logo] == '0' ? nil : PromotionalLogo.find(params[:promotional_logo])
if (#promotional_logo && #ad_group.promotional_logo.nil?) || (#promotional_logo.nil? && #ad_group.promotional_logo)
#ad_group.promotional_logo = #promotional_logo
#ad_group.adjust_for_promotional_logo
end
#ad_group.update_attributes(make: #make, car: #car, trim: #trim, client: #client, rollover: params[:ad_group][:rollover], promotional_logo: #promotional_logo || nil)
AdGroup.fields.each do |field|
#ad_group[field] = params[:ad_group][field]
end
end
#ad_group.ads.each do |ad|
url = #ad_group.car.file.blank? ? nil : #ad_group.car.file.url
car = #ad_group.car.file.blank? ? nil : #ad_group.car
ad.images.find_by(name: 'car').update(url: url, car: car)
url = #ad_group.promotional_logo.blank? ? nil : #ad_group.promotional_logo.file.url
logo = #ad_group.promotional_logo.blank? ? nil : #ad_group.promotional_logo
ad.images.find_by(name: "promotional_logo").update(url: url, promotional_logo: logo)
ad.texts.find_by(name: "client_name").update(content: #client.name)
if #ad_group.car.blank?
car_name = ''
else
car_name = "#{#car.year} #{#make.name} #{#car.model}"
car_name += " #{#car.trim}" unless params[:trim] == 'none' || params[:trim].blank?
end
ad.texts.find_by(name: "car_name").update(content: car_name)
Basically the if statement it's stating that if's there is a file in the adgroup paramaters create a car, and if not it should stay as
#car = Car.find(params[:ad_group][:car][:id])
the code below that has to execute for both cases. what is the best way to do this without repeating the code in the if and the else.
Related
My code
require "json"
require "erb"
flowvar = $workflowvar
path = 'src/main/resources/'+$workflowvar+'.drl'
rule = ""
File.open(path,"w") do |f|
f.puts "package com.drools.demo\;"+"\n"+"import org.mule.MessageExchangePattern\;"+"\n"+"import com.drools.demo.cashliquidassets\;"+"\n"+"global org.mule.module.bpm.MessageService mule\;"+"\n"+
"dialect \"mvel\""+"\n"+"dialect \"java\""+"\n"+"declare cashliquidassets"+"\n"+"#role\(\'event\'\)"+"\n"+"end"+"\n"
f.close
end
def concateRule(attribute,val)
if(val==null || val=="")
return "";
end
if(attribute != null)
if (attribute == "taxonomy_code" || attribute == "parent_taxonomy_code" || attribute == "report_name")
return "";
end
end
if val.start_with('<>')
return attribute+" != "+val[3,val.length].strip
elsif val.start_with('>')
return attribute+" > "+val
elsif val.start_with('<')
return attribute+" < "+val
elsif val.include? ","
return attribute+".contains("+val+"\)"
else
return attribute+" == "+ val
end
end
json = JSON.parse($payload)
json.each do |hash1|
hash1.keys.each do |key|
hash1[key].each do |inner_hash,value|
#inner_hash = inner_hash
#values = value
str = concateRule #inner_hash,$values
end
end
end
Compile is working fine, but in runtime, I am getting this following error. Any suggestions
Root Exception stack trace:
org.jruby.exceptions.RaiseException: (NameError) undefined local
variable or method `null' for main:Object
at RUBY.concateRule(<script>:15)
at RUBY.block in (root)(<script>:43)
at org.jruby.RubyHash.each(org/jruby/RubyHash.java:1350)
at RUBY.block in (root)(<script>:40)
at org.jruby.RubyArray.each(org/jruby/RubyArray.java:1735)
at RUBY.block in (root)(<script>:39)
at org.jruby.RubyArray.each(org/jruby/RubyArray.java:1735)
at RUBY.<main>(<script>:38)
You need to use nil instead of null.
So, just replace it.
Following the conversation in the comments above, here is how I would write the method:
def concat_rule(attribute, val)
val = val.to_s
if val == '' || ['taxonomy_code', 'parent_taxonomy_code', 'report_name'].include?(attribute)
return ''
end
if val.start_with?('<>')
"#{attribute} != #{val[3..-1].strip}"
elsif val.start_with?('>')
"#{attribute} > #{val}"
elsif val.start_with?('<')
"#{attribute} < #{val}"
elsif val.include?(',')
"#{attribute}.contains(#{val})"
else
"#{attribute} == #{val}"
end
end
A few notes:
Using snake_case method names and 2 space tabs, is a very strongly adhered to style guide in the ruby community.
Similarly, you can make use of ruby's implicit return, to shorten the code: The final value at the end of a method is returned automatically.
Adding val = val.to_s to the top of this method simplifies the rest of the code; eliminating the need to repeatedly convert to a string or perform nil checks.
You can use ruby's string interpolation ("#{code-to-evaluate}") syntax as a more elegant way to define strings than repeated use of + for concatenation.
I have created Rails application and I have used lots of instance variables and most of them are not required in the views. Do I need to replace the unused instance variables for improving the performance?
Sample code:
def show
custom_fields_data = fetch_custom_field_data
#selected_custom_fields_opt_from_view = []
if custom_fields_data.present?
#listings = #listing.category.listings.where("price_cents!=? AND open= ?",0,true).reject { |l| l.author.main_admin? }
#selected_custom_fields_opt_from_view = custom_fields_data.map do |custom_field_data|
CustomField.find(custom_field_data[0]).options.find(custom_field_data[1])
end
#listings.each do |listing|
# array to store the selected a custom field's option from Database
selected_custom_fields_opt_from_db = []
listing.custom_field_values.each do |custom_field_value|
selected_custom_fields_opt_from_db.push(custom_field_value.selected_options.first)
end
if selected_custom_fields_opt_from_db.uniq.sort == #selected_custom_fields_opt_from_view.uniq.sort || (#selected_custom_fields_opt_from_view - selected_custom_fields_opt_from_db).empty?
similar_listing.push(listing)
end
end
#listings = similar_listing
end
#listing_with_filters = similar_listing.present? ? #listings.first : #listing
#selected_tribe_navi_tab = "home"
unless current_user?(#listing.author)
#listing.increment!(:times_viewed)
end
#current_image = if params[:image]
#listing.image_by_id(params[:image])
else
#listing.listing_images.first
end
#prev_image_id, #next_image_id = if #current_image
#listing.prev_and_next_image_ids_by_id(#current_image.id)
else
[nil, nil]
end
payment_gateway = MarketplaceService::Community::Query.payment_type(#current_community.id)
process = get_transaction_process(community_id: #current_community.id, transaction_process_id: #listing.transaction_process_id)
form_path = new_transaction_path(listing_id: #listing.id)
delivery_opts = delivery_config(#listing.require_shipping_address, #listing.pickup_enabled, #listing.shipping_price, #listing.shipping_price_additional, #listing.currency)
#category = #listing.category
#template_listing = #category.template_listing
if #current_user
# For Pivot table
#selected_custom_field = params[:custom_field] if params[:custom_field]
#listing_for_pivot = Listing.new
#listing_images = #listing.listing_images
#shape = get_shape(#listing.listing_shape_id)
#unit_options = ListingViewUtils.unit_options(#shape[:units], unit_from_listing(#template_listing)).first if #shape
#custom_field_questions = #category.custom_fields
#numeric_field_ids = numeric_field_ids(#custom_field_questions)
#category_tree = CategoryViewUtils.category_tree(
categories: ListingService::API::Api.categories.get(community_id: #current_community.id)[:data],
shapes: get_shapes,
locale: I18n.locale,
all_locales: #current_community.locales
)
if #template_listing.present?
#listing_for_pivot.title = #template_listing.title
#listing_for_pivot.description = #template_listing.description
#listing_images = #template_listing.listing_images if #template_listing.listing_images.present?
#listing_for_pivot.listing_shape_id = #template_listing.listing_shape_id
end
if (#current_user.location != nil)
temp = #current_user.location
temp.location_type = "origin_loc"
#listing_for_pivot.build_origin_loc(temp.attributes)
else
#listing_for_pivot.build_origin_loc(:location_type => "origin_loc")
end
#custom_field_area = CategoryCustomField.where(category_id: #category.id, custom_field_id: #category.custom_fields.pluck(:id))
#row = #category.custom_field_row
#row = #custom_field_area.first.custom_field if #row.nil? && #custom_field_area.first
#column = #category.custom_field_column
#column = #custom_field_area.second.custom_field if #column.nil? && #custom_field_area.second
#filters = #category.custom_field_filters
#filters = #custom_field_area.all.from(1).map { |category_custom_field| category_custom_field.custom_field } if #filters.nil? && #custom_field_area.size > 2
#selected_value_for_filter = []
if #filters.present?
if #selected_custom_field
#filters.each do |filter|
if (#selected_custom_field["#{filter.id.to_s}_"])
#selected_value_for_filter.push(filter.options.find(#selected_custom_field["#{filter.id.to_s}_"]))
else
#selected_value_for_filter.push(filter.options.first)
end
end
else
#filters.each do |filter|
#selected_value_for_filter.push(filter.options.first)
end
end
end
# Pivot table section end
end
#applicant = #category.listings.pluck(:author_id).uniq
#suggested_business_accounts = #category.people.where("people.id NOT IN (?)", #applicant);
if #suggested_business_accounts.present?
#business_locations =
#suggested_business_accounts.map do |person|
person.location
end
#business_locations.compact!
end
render locals: {
form_path: form_path,
payment_gateway: payment_gateway,
# TODO I guess we should not need to know the process in order to show the listing
process: process,
delivery_opts: delivery_opts,
listing_unit_type: #listing.unit_type
}
end
It is not recommended to use instance variables if you don't want to send them to views. The scope of the variables should be narrowest, therefore in your case if you are not using instance variables in the views you should convert them to local.
Using instance variables instead of local variables is a bad idea at least memory-wise.
Instance variable exists while the object that holds it exists. On the contrary, local variable exists only inside method/block it is defined.
Garbage collector does not care whether you use instance variable elsewhere beyond the method or not.
Thus, if you have instance variables, which you only intend to use within the method - change them to local ones.
I have a show page for my Users and each attribute should only be visible on that page, if it is not nil and not an empty string. Below I have my controller and it is quite annoying having to write the same line of code #user.city != nil && #user.city != "" for every variable. I am not too familiar with creating my own methods, but can I somehow create a shortcut to do something like this: #city = check_attr(#user.city)? Or is there a better way to shorten this procedure?
users_controller.rb
def show
#city = #user.city != nil && #user.city != ""
#state = #user.state != nil && #user.state != ""
#bio = #user.bio != nil && #user.bio != ""
#contact = #user.contact != nil && #user.contact != ""
#twitter = #user.twitter != nil && #user.twitter != ""
#mail = #user.mail != nil && #user.mail != ""
end
There's a method that does this for you:
def show
#city = #user.city.present?
end
The present? method tests for not-nil plus has content. Empty strings, strings consisting of spaces or tabs, are considered not present.
Since this pattern is so common there's even a shortcut in ActiveRecord:
def show
#city = #user.city?
end
This is roughly equivalent.
As a note, testing vs nil is almost always redundant. There are only two logically false values in Ruby: nil and false. Unless it's possible for a variable to be literal false, this would be sufficient:
if (variable)
# ...
end
This is preferable to the usual if (!variable.nil?) or if (variable != nil) stuff that shows up occasionally. Ruby tends to wards a more reductionist type of expression.
One reason you'd want to compare vs. nil is if you have a tri-state variable that can be true, false or nil and you need to distinguish between the last two states.
You can use .present? which comes included with ActiveSupport.
#city = #user.city.present?
# etc ...
You could even write it like this
def show
%w(city state bio contact twitter mail).each do |attr|
instance_variable_set "##{attr}", #user[attr].present?
end
end
It's worth noting that if you want to test if something is blank, you can use .blank? (this is the opposite of .present?)
Also, don't use foo == nil. Use foo.nil? instead.
I have two filters that get checked for my Rails model called Items. If both filters are enabled, Ie: certain params are passed then it filters down the Items based on the first one and then should use the results of the first filter as the basis to filter from the second. But it doesn't like me calling .where on the instance variable of #items which is being passed to my view? Any thoughts?
Error is :
undefined method `where' for #
Code:
#coasters = Coaster.all
if params[:type]
type = params[:type]
if type == 'powered'
#coasters = #coasters.where("style = ?", "powered")
else
#coasters = #coasters.where("material LIKE ?", params[:type])
end
end
if params[:letters]
letters = params[:letters]
if letters == '#'
#coasters = #coasters.all.select { |r| /^[0-9].*/ =~ r.name }
else
letters = letters.split('-')
lettersLower = (letters[0]..letters[1]).to_a
lettersUpper = (letters[0].upcase..letters[1].upcase).to_a
letters = lettersLower.concat(lettersUpper)
conditions = (letters.map{ |letter| " name ILIKE '#{letter}%' " }.join('OR'))
#coasters = #coasters.where(conditions)
end
end
I have a module:
module Voteable
def has_up_vote_of user
return ! self.votes.select{|v| v.user.id == user.id && v.value == 1}.empty?
end
def has_down_vote_of user
return ! self.votes.select{|v| v.user.id == user.id && v.value == -1}.empty?
end
end
Which is mixed into a model:
class Comment < ActiveRecord::Base
include Voteable
end
In a controller code, there is a check:
has_up_vote = #voteable.has_up_vote_of #user
has_down_vote = #voteable.has_down_vote_of #user
#voteable and #user are existing model items, found in a DB.
Suppose, voteable item has up-vote of user. After executing the code, has_up_vote will be equal to true, and has_down_vote will be nil.
Why nil, instead of false ?
I have used several variations of methods, but the problem is the same. Even this gives me the same effect:
def has_up_vote_of user
has = self.votes.select{|v| v.user.id == user.id && v.value == 1}.empty?
return !has.nil? && has
end
Posssible, i'm misunderstanding something, but this behavior is strange
Update
I've noticed very strange behaviour.
When i change methods to trivial:
def has_up_vote_of user
return false
end
def has_down_vote_of user
return false
end
They both returns nil, when i debug the app.
But, from console, they returns false.
It's more stange, because i cannot do anything with these results. These code is not working:
has_up_vote = false if has_up_vote.nil?
has_down_vote = false if has_down_vote.nil?
I think that the debugging environment you're running in is interfering with the actual value of has_down_votes. The select method should never return nil as defined.
Instead of !{}.empty? you could use {}.present?
Its more readable and the output will always be true/false only
I know this doesn't get to the root cause of your strange problem, but it should give you the results you want. Instead of
return ! self.votes.select{|v| v.user.id == user.id && v.value == -1}.empty?
try
return !!self.votes.select{|v| v.user.id == user.id && v.value == -1}.any?
The double exclamation point is intentional -- it will cause nil to become false. (!arr.empty? is equivalent to arr.any? which is equivalent to !!arr.any? -- except the last one converts the nil to false)