Rails controller variable mess - ruby-on-rails

I have a controller that I feel has too many instance variables.
The controller is pulling data from various places and it feels really sloppy.
I have watched some Sandi Metz talks, read books, and other research, and I want to have good practice but I just don't know what to do here.
This method is pulling all the data and sending it to my view and I am able to get it to work, I just know this isn't a good way to go about it and I am hoping someone can point me to some code samples, documentation, videos, or help me understand how to implement a better style.
I have searched on SO and Google but I mostly find people saying to send a hash or JSON to the view, and I want to know if that is ideal before I start on that.
The Client, Project, Person, Role controllers and models have really similar code and I am working on refactoring it to be more DRY.
For example the Client, Project, Person, and Role financial controllers have almost the exact same controller index code as this. :(
I would be happy to add more code if that would help!
This is the project_financials_controller#index
It's pretty much taking in the data from the view and pulling a bunch of data from the database and sending it to a view. I'm currently using only the index method because it was only supposed to be a 'view' but now we can add filters such as time, different clients, etc so I think I need to break it out somehow.
I do have a financial_reports_nav model that this is calling that I could maybe use more, Or even make a financial_reports_controller that pulls the data from the appropriate model and I wont even need the 4 different controllers...
I am totally open to any input/criticism!
def index
# CPPR = Client, Project, Person, Role
#financial_type = 'project'
#financial_params = params
# This pulls the timeframe from the view and figures out the dates requested. (eg. "Last Week")
#timeframe = Financial.time_frame(#financial_params[:timeframe], current_company.timezone, params[:start_date], params[:end_date])
# This grabs all the data required to recall this financial report view at a later time
#financial_nav = FinancialReportNav.set_financial_type(#current_user.id,#financial_type, #start_date, #end_date)
# Grab all active and inactive people for client
#people = Person.active.all
#deleted_people = Person.inactive.all
# This sends over all the info needed to generate the financial reports
#project_financial_populate = Financial.new(#financial_params, #financial_type).populate_project_financials(current_company.default_hourly_cost, current_company.billing_rate, #timeframe[:start_date],#timeframe[:end_date])
# This just pulls all the data from the database that the #project_financial_populate just populated (Can't we just use that??)
#financial_rows = ProjectFinancial.all.map { |p| [ p.project_id, p.billable_hours, p.revenue,p.real_rate, p.hourly_expense, p.labor_expense_total, p.salary_expense, p.gross_profit, p.profit_margin, p.missing_hourly_expense, p.missing_billable_rate ] }
# Using the same view for CPPR's
# Clients has an items count, so we just stuff everything into the first array slot
#items = [1]
# If these are not null then they show an option to change the financial filter type.
#filter_by_client = Client.find_by('id = ?', #financial_params[:filter_by_client])
#filter_by_project = Project.find_by('id = ?', #financial_params[:filter_by_project])
#filter_by_person = Person.find_by('id = ?', #financial_params[:filter_by_person])
#filter_by_role = PersonRole.find_by('id = ?', #financial_params[:filter_by_role])
# This pulls a list of CPPR's that have tracked time in the requested timeframe
#project_list = Financial.project_list(#timeframe[:start_date], #timeframe[:end_date])
#client_list = Financial.client_list(#timeframe[:start_date], #timeframe[:end_date])
#people_list = Financial.people_list(#timeframe[:start_date], #timeframe[:end_date])
end

I always tend to refactor code to be DRY whenever I noticed I have at least 3 instances of duplicate code, but I needed to future-proof the new code to be flexible enough for possible future changes; all of this considered however time permits.
Given your already current code and having told my preferences, this is what I would do:
Model Inheritance
Controller Inheritance
Shared template
Routes
config/routes.rb
resources :client_financial
resources :project_financial
resources :person_financial
resources :role_financial
Models
app/models/financial_record.rb
class FinancialRecord < ActiveRecord::Base # or ApplicationRecord if > Rails 5
self.abstract_class = true
# your shared "financials" model logic here
end
app/models/client_financial.rb
class ClientFinancial < FinancialRecord
# override "financials" methods here if necessary
# or, add new model specific methods / implementation
end
app/models/project_financial.rb
class ProjectFinancial < FinancialRecord
# override "financials" methods here if necessary
# or, add new model specific methods / implementation
end
app/models/person_financial.rb
class PersonFinancial < FinancialRecord
# override "financials" methods here if necessary
# or, add new model specific methods / implementation
end
app/models/role_financial.rb
class RoleFinancial < FinancialRecord
# override "financials" methods here if necessary
# or, add new model specific methods / implementation
end
Controllers
app/controllers/financial_controller.rb
class FinancialController < ApplicationController
before_action :set_instance_variables, only: :index
protected
def set_instance_variables
# strips the last "Controller" substring and change to underscore: i.e. ProjectFinancialsController becomes project_financials
#financial_type = controller_name[0..(-'Controller'.length - 1)].underscore
# get the corresponding Model class
model = #financial_type.camelcase.constantize
# get the correspond Financial Model class
financial_model = "#{#financial_type.camelcase}Financial".constantize
#financial_params = params
#timeframe = Financial.time_frame(#financial_params[:timeframe], current_company.timezone, params[:start_date], params[:end_date])
# I dont know where you set #start_date and #end_date
#financial_nav = FinancialReportNav.set_financial_type(#current_user.id,#financial_type, #start_date, #end_date)
# renamed (or you can set this instance variable name dynamically)
#records = model.active.all
# renamed (or you can set this instance variable name dynamically)
#deleted_records = model.inactive.all
#financial_populate = Financial.new(#financial_params, #financial_type).populate_project_financials(current_company.default_hourly_cost, current_company.billing_rate, #timeframe[:start_date],#timeframe[:end_date])
#financial_rows = financial_model.all.map { |p| [ p.project_id, p.billable_hours, p.revenue,p.real_rate, p.hourly_expense, p.labor_expense_total, p.salary_expense, p.gross_profit, p.profit_margin, p.missing_hourly_expense, p.missing_billable_rate ] }
#items = [1]
#filter_by_client = Client.find_by('id = ?', #financial_params[:filter_by_client])
#filter_by_project = Project.find_by('id = ?', #financial_params[:filter_by_project])
#filter_by_person = Person.find_by('id = ?', #financial_params[:filter_by_person])
#filter_by_role = PersonRole.find_by('id = ?', #financial_params[:filter_by_role])
#project_list = Financial.project_list(#timeframe[:start_date], #timeframe[:end_date])
#client_list = Financial.client_list(#timeframe[:start_date], #timeframe[:end_date])
#people_list = Financial.people_list(#timeframe[:start_date], #timeframe[:end_date])
end
end
app/controllers/client_financials_controller.rb
class ClientFinancialsController < FinancialController
def index
render template: 'financials/index'
end
end
app/controllers/project_financials_controller.rb
class ProjectFinancialsController < FinancialController
def index
render template: 'financials/index'
end
end
app/controllers/person_financials_controller.rb
class ProjectFinancialsController < FinancialController
def index
render template: 'financials/index'
end
end
app/controllers/role_financials_controller.rb
class ProjectFinancialsController < FinancialController
def index
render template: 'financials/index'
end
end
Views
app/views/financials/index.html.erb
<!-- YOUR SHARED "FINANCIALS" INDEX HTML HERE -->
P.S. This is just a simple refactor. Without knowing the fuller scope of the project, and future plans, I'll just do this one. Having said this, I would consider using "polymorpic" associations, and then just have one routes endpoint (i.e. resources :financials) and then just pass in a params filter like: params[:financial_type] which directly already map the financial_type polymorphic column name.

Related

building a simple search form in Rails?

I'm trying to build a simple search form in Ruby on Rails, my form is simple enough basically you select fields from a series of options and then all the events matching the fields are shown. The problem comes when I leave any field blank.
Here is the code responsible for filtering the parameters
Event.joins(:eventdates).joins(:categories).where
("eventdates.start_date = ? AND city = ? AND categories.name = ?",
params[:event][:date], params[:event][:city], params[:event][:category]).all
From what I get it's that it looks for events with any empty field, but since all of them have them not empty, it wont match unless all 3 are filled, another problem arises when I try to say, look events inside a range or array of dates, I'm clueless on how to pass multiple days into the search.
I'm pretty new to making search forms in general, so I don't even know if this is the best approach, also I'm trying to keep the searches without the need of a secialized model.
Below is probably what you are looking for. (Note: If all fields all blank, it shows all data in the events table linkable with eventdates and categories.)
events = Event.joins(:eventdates).joins(:categories)
if params[:event]
# includes below where condition to query only if params[:event][:date] has a value
events = events.where("eventdates.start_date = ?", params[:event][:date]) if params[:event][:date].present?
# includes below where condition to query only if params[:event][:city] has a value
events = events.where("city = ?", params[:event][:city]) if params[:event][:city].present?
# includes below where condition to query only if params[:event][:city] has a value
events = events.where("categories.name = ?", params[:event][:category]) if params[:event][:category].present?
end
To search using multiple days:
# params[:event][:dates] is expected to be array of dates.
# Below query gets converted into an 'IN' operation in SQL, something like "where eventdates.start_date IN ['date1', 'date2']"
events = events.where("eventdates.start_date = ?", params[:event][:dates]) if params[:event][:dates].present?
It will be more easy and optimised . If you use concern for filter data.
Make one concern in Model.
filterable.rb
module Filterable
extend ActiveSupport::Concern
module ClassMethods
def filter(filtering_params)
results = self.where(nil)
filtering_params.each do |key, value|
if column_type(key) == :date || column_type(key) ==
:datetime
results = results.where("DATE(#{column(key)}) = ?",
Date.strptime(value, "%m/%d/%Y")) if
value.present?
else
results = results.where("#{column(key)} Like ? ", "%#{value}%") if
value.present?
end
end
results
end
def resource_name
self.table_name
end
def column(key)
return key if key.split(".").count > 1
return "#{resource_name}.#{key}"
end
def column_type(key)
self.columns_hash[key].type
end
end
end
Include this concern in model file that you want to filter.
Model.rb
include Filterable
In your controller Add this methods
def search
#resources = Model.filter(class_search_params)
render 'index'
end
def class_search_params
params.slice(:id,:name) #Your field names
end
So, It is global solution. You dont need to use query for filter. just add this concern in your model file.
That's it.

ActiveModel::MissingAttributeError in Controller can't write unknown attribute

For one of the views in my rails application, I have set up the controller as such. I want to get all students records from the db and append extra values to each student. This is giving me the error:
ActiveModel::MissingAttributeError in MemoMainTesterController#test_students
can't write unknown attribute current_target
class MemoMainTesterController < ApplicationController
def test_students
#all_students = Student.all
#all_students.each do |student|
current = current_target(student)
previous_test_info = last_pass(student)
student[:current_target] = current[0]
student[:current_level] = current[1]
student[:current_target_string] = "Level #{current[0]} - Target #{current[1]}"
student[:last_pass] = previous_test_info[0]
student[:attempts] = previous_test_info[1]
student[:last_pass_string] = previous_test_info[2]
end
end
.
.
.
end
It occurs specifically where student[:current_target] = current[0].
Am I not allowed to append extra values to this hash?
Is there a workaround for this?
EDIT: Although Student.all is a model instance, I want to turn it into a hash and append more key value pairs to it.
In your case, student is not a Hash but a Student model instance.
When you call student[:current_target] you are attempting to write Student's current_target attribute, which surely is not an actual attribute in the DB for students table. Hence the error.
To obtain a hash from your models containing the extra data, you may consider this refactor:
class MemoMainTesterController < ApplicationController
def test_students
#all_students = Student.all
#students_with_steroids = #all_students.map do |student|
current = current_target(student)
previous_test_info = last_pass(student)
student_attributes = student.attributes # <= this is a hash, that you store in student_attributes hash variable
student_attributes.merge(current_target: current[0],
current_level: current[1],
current_target_string: "Level #{current[0]} - Target #{current[1]}",
last_pass: previous_test_info[0],
attempts: previous_test_info[1],
last_pass_string: previous_test_info[2])
end
end

Rails 4 Create Related Object After Save

I have two models with the [fields]:
Order [:date]
Delivery Slot [:day]
Order belongs_to :delivery_slot
When an order is created, I want a delivery slot to be created with the :day set to the order :date.
So far I have created a new method create_delivery_slots in the Order controller that creates a Delivery Slot when the Order is created, but where I am stumped is, how do I get the Order :date in the Delivery Slot :day field?
#Create delivery slots if they dont already exist
def create_delivery_slots
existingslots = []
existingslots = DeliverySlot.all.select {|slot| slot.day == #order.date}
if existingslots.empty?
slot = DeliverySlot.new(:day => #order.date)
slot.save!
end
I have tried multiple approaches, but no luck. My gut tells me its something to do with strong parameters but I can't figure it out...
I'm not sure exactly of how you're set up but you'll probably want something like this:
class Order < ActiveRecord::Base
has_a :delivery_slot
after_create => :create_delivery_slots
.
#other code stuffs
.
.
private
def create_delivery_slots
existingslots = []
existingslots = DeliverySlot.all.select {|slot| slot.day == self.date}
if existingslots.empty?
slot = DeliverySlot.new(:day => self.date)
slot.save!
end
end
end
That's untested but it should be basically what you need.

Creating new class to put into an Array in Ruby

I am coming from a C# background and trying to learn Ruby and Ruby on Rails. I have the following Car class - note the build_xml method I need in order to build XML in that syntax and then pass to a WebService
class Car
##array = Array.new
#this will allow us to get list of all instances of cars created if needed
def self.all_instances
##array
end
def initialize(id, model_number, engine_size, no_doors)
# Instance variables
#id = id
#model_number = model_number
#engine_size = engine_size
#no_doors = no_doors
##array << self
end
def build_car_xml
car = { 'abc:Id'=> #id, 'abc:ModelNo' => #model_number, 'abc:ES' => #engine_size, 'abc:ND' => #no_doors}
cars = {'abc:Car' => [car] }
end
end
In another class then I was using this as below:
car1 = Car.new('1', 18, 3.0, 4)
request = car1.build_car_xml
This works as expected and the request is formatted how I need and the webservice returns the results. I now want to expand this however so I can pass in an array of cars and produce the request XML - however I am struggling to get this part working.
So far I have been trying the following (for now I am ok with just the Id changing as it is the only parameter required to be unique):
car_array = []
(1..10).each do |i|
car_array << Car.new(i.to_s, 18, 3.0, 4)
end
Am I correct in saying that I would need to define a new build_car_xml method on my Car class that can take an array of cars and then build the xml so my request call would be something like:
request = Car.build_car_xml(car_array)
What i am unsure of is 1) - is this the correct way of doing things in Ruby and 2) how to construct the method so that it is Building the XML in the correct format in the way it was when I call it on the single object - i.e - I need the namespaces added before the actual value.
def build_car_xml(car_array)
#here is where I am unsure how to contruct this method
end
Possible solution ('abc:Car' is a wrong name, should be Cars if you want it to hold an array):
class Car
...
def self.build_cars_xml(cars)
{ 'abc:Car' => cars.map(&:build_car_xml) }
end
def build_car_xml
{ 'abc:Id'=> #id, 'abc:ModelNo' => #model_number, 'abc:ES' => #engine_size, 'abc:ND' => #no_doors }
end
end
cars =
(1..10).map do |i|
Car.new(i.to_s, 18, 3.0, 4)
end
Car.build_cars_xml(cars)
It doesn't meet your requirements as instance build_car_xml doesn't generate Car namespace, but for me it's some inconsistency. Your XML is actually a collection, even if it has just one element, instance method should not be responsible for collection. Car.build_cars_xml([Car.new(...)] looks more logical to me.

Is it possible to define two methods in a Rails model that require different initialization?

Hi I'm attempting to create a model in Rails that can perform two calculations. This is my code:
class Calculator
def initialize(nair, cppy, interest_rate, payment, periods)
#nair = nair.to_f / 100
#cppy = cppy.to_f
#interest_rate = interest_rate
#payment = payment
#periods = periods
end
def effective
Refinance::Annuities.effective_interest_rate(#nair, #cppy)
end
def principal
Refinance::Annuities.principal(#interest_rate, #payment, #periods)
end
end
I have two forms that reside in different views that take input from the user including 'nair' and 'cppy' on one and 'interest_rate', 'payment' and 'periods' on the other.
The problem I've run into is that to use this model all five arguments need to be available.
Do I need to have separate models for each calculation?
I'm a complete beginning sorry if there is a really obvious answer.
Thanks!
There's probably a dozen different ways you could solve this, but one possible approach would be to use default arguments in your initialize method.
class Calculator
def initialize(nair=0, cppy=0, interest_rate=0, payment=0, periods=0)
#nair = nair.to_f / 100
#cppy = cppy.to_f
#interest_rate = interest_rate
#payment = payment
#periods = periods
end
def effective
Refinance::Annuities.effective_interest_rate(#nair, #cppy)
end
def principal
Refinance::Annuities.principal(#interest_rate, #payment, #periods)
end
end
Another possible solution is to make them class methods and not deal with instances or state:
class Calculator
def self.effective(nair, cppy)
nair = nair.to_f / 100
cppy = cppy.to_f
Refinance::Annuities.effective_interest_rate(nair, cppy)
end
def self.principal(interest_rate, payment, periods)
Refinance::Annuities.principal(interest_rate, payment, periods)
end
end
Calculator.effective(x, y)
Calculator.principal(x, y, z)

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