Ruby: Keeping track of Stock Transaction using Hash

问题

I am new to Ruby, and I am trying to code a "simple" system, so I can keep track of stock transaction. Calculating the average price, and in the future I will try to get dividends information.

So far, my code looks like this (PLEASE feel free to propose better ways to do my code, as I said, I am new).

require 'money'
require 'money/bank/google_currency'
require 'monetize'
require 'date'
require 'ystock'
require 'ostruct'

# (optional)
# set the seconds after than the current rates are automatically expired
# by default, they never expire
Money::Bank::GoogleCurrency.ttl_in_seconds = 86400
I18n.enforce_available_locales = false #erro no formatting...
# set default bank to instance of GoogleCurrency
Money.default_bank = Money::Bank::GoogleCurrency.new

class Stock

attr_accessor :code, :quantity, :price, :transactions, :spotprice

    def initialize(code:)
        @code = code
        @quantity =00
        @price = 00.to_money(:BRL)
        @transactions = []
        @spotprice = 0.to_money(:BRL)
    end    

    def spotprice
        begin
            asset_temp = Ystock.quote(@code.to_s + ".sa") # since it is South America.
            asset_info = OpenStruct.new asset_temp # organize it.
            @spotprice = asset_info.price.to_money(:BRL) # get the price. And transform it to Money, local currency
        rescue => @error #Is there an TCP/IP error?
            @spotprice = 0.to_money(:BRL)
        end
    end

    def buy (quantity:, price:, fees:, date:0)
        transactions.push type: "BUY", date: Date.strptime(date.to_s, '%d/%m/%Y'), quantity: quantity, price: price.to_money(:BRL), fees: fees.to_money(:BRL)
        #Lets calculate the average price that we bought:
        new_price = (((@quantity * @price.to_money(:BRL))) + ((quantity * price.to_money(:BRL)) + fees.to_money(:BRL))) / (@quantity + quantity)
        @quantity += quantity
        @price = new_price.to_money(:BRL) # new price is the average price.
    end

    def sell (quantity:,price:, fees:, date:)
        transactions.push type: "SELL", date: Date.strptime(date.to_s,     '%d/%m/%Y'), quantity: quantity, price: price.to_money(:BRL), fees:     fees.to_money(:BRL)
        @quantity -= quantity
    end
end

For example, I can create the asset, and make buys and sells:

ciel3 = Stock.new(code: "CIEL3")
ciel3.buy(quantity: 100, price: 9.00, fees: 21.5, date: "12/05/2015")
 p ciel3
ciel3.buy(quantity: 100,price: 12, fees: 21.7, date: "12/06/2015")
ciel3.sell(quantity: 50,price: 11.5,fees: 20.86, date: "20/06/2015")
p ciel3
ciel3.buy(quantity: 200,price: 15,fees: 23.6, date: "12/07/2015")
puts ciel3.price.format
puts
puts
# puts ciel3.spotprice.format
p ciel3.transactions 

So far, it is OK (but I think that there is a cleaner and more readable way to do it... not sure).

But lets suppose I want to view all the transactions of the type "SELL". How can I do this? How to look inside the ciel3.transaction array, that has the hash :type ?? Tnks

回答1:

Instead of using a hash, you probably want a Transaction class.

If you back it with a DB and use ActiveRecord, then searching will be very simple.

If not, you can do ciel3.transactions.select{|t| t[:type] == 'SELL'}

回答2:

I wrote a simple command line inventory management app in Ruby. You can probably reuse a lot of code for your project.

It's on my GitHub: https://github.com/brunofacca/udacity-inventory-manager

来源：https://stackoverflow.com/questions/38512210/ruby-keeping-track-of-stock-transaction-using-hash