Class: Money::Bank::ECB

Inherits:
VariableExchange
  • Object
show all
Defined in:
lib/money/bank/ecb.rb,
lib/money/bank/ecb/cache.rb,
lib/money/bank/ecb/cache_file.rb,
lib/money/bank/ecb/simple_cache.rb

Overview

This class represents the European Central Bank or more precisely, its foreign exchange rates.

Defined Under Namespace

Modules: Cache Classes: CacheFile, InvalidCacheError, SimpleCache

Constant Summary collapse

RATES_URL = 
'http://www.ecb.europa.eu/stats/eurofxref/eurofxref.zip'

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(cache = nil) {|x| ... } ⇒ Money::Bank::ECB

Creates an Money::Bank::ECB.

Examples:

Money::Bank::ECB.new {|x| x.floor}
#=> #<Money::Bank::ECB
      @rounding_method=#<Proc>,
      @auto_update=true,
      @rates=#<Hash>,
      @rates_date=#<Time>,
      @currencies=#<Array>>

Yields:

  • (x) —

    Optional block to use for rounding after exchanging.

Yield Parameters:

  • x (Float) —

    The exchanged amount of cents to be rounded.

Yield Returns:

  • (Integer) 


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# File 'lib/money/bank/ecb.rb', line 58

def initialize(cache = nil, &rounding_method)
  @cache = self.class.build(cache)
  super(&rounding_method)

  setup
end

Instance Attribute Details

#auto_update ⇒ true, false

Auto-updating on or off.



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# File 'lib/money/bank/ecb.rb', line 34

class ECB < Money::Bank::VariableExchange
  # Error thrown when the cache file to be loaded isn't "good enough".
  class InvalidCacheError < StandardError; end

  RATES_URL = 'http://www.ecb.europa.eu/stats/eurofxref/eurofxref.zip'

  # Creates an Money::Bank::ECB.
  #
  # @param [String] cache_filename Absolute path and filename to the cache.
  #
  # @yield [x] Optional block to use for rounding after exchanging.
  # @yieldparam [Float] x The exchanged amount of cents to be rounded.
  # @yieldreturn [Integer]
  #
  # @return [Money::Bank::ECB]
  #
  # @example
  #   Money::Bank::ECB.new {|x| x.floor}
  #   #=> #<Money::Bank::ECB
  #         @rounding_method=#<Proc>,
  #         @auto_update=true,
  #         @rates=#<Hash>,
  #         @rates_date=#<Time>,
  #         @currencies=#<Array>>
  def initialize(cache = nil, &rounding_method)
    @cache = self.class.build(cache)
    super(&rounding_method)

    setup
  end

  # Builds a Cache from input.
  #
  # @param [*] something The thing to build a Cache from.
  # @return [Cache]
  def self.build(cache)
    case cache
    when Money::Bank::ECB::Cache
      cache
    when String
      Money::Bank::ECB::CacheFile.new(cache)
    else
      Money::Bank::ECB::SimpleCache.new
    end
  end

  attr_reader :cache
  attr_accessor :auto_update

  # Setup rates hash, mutex for rates locking, and auto_update default.
  #
  # @return [self]
  def setup
    @auto_update = true
    super
    reload rescue update
  end

  # Exchange some money
  #
  # @param [Money] from To exchange from.
  # @param [String,Symbol] to Currency to exchange to.
  # @yield [x] Optional block to use for rounding after exchanging.
  # @yieldparam [Float] x The exchanged amount of cents to be rounded.
  # @yieldreturn [Integer]
  #
  # @return [Money]
  #
  # @example
  #   ecb.exchange_with(Money.new(100, :EUR), :USD)
  def exchange_with(from, to, &rounding_method)
    update if @auto_update and Time.now.utc > (@rates_date + 60*60*24)
    super(from, to, &rounding_method)
  end

  # Update the cache file and load the new rates.
  #
  # This is only relevant if #auto_update is false.
  #
  # @return [self]
  def update
    update_cache
    reload

    self
  end

  # Update the cache.
  #
  # @return [self]
  def update_cache
    Zip::InputStream.open(open(RATES_URL)) do |io|
      io.get_next_entry
      @cache.set(io.read)
    end

    self
  end

  attr_reader :currencies
  attr_reader :rates_date

  # Load rates from the cache file.
  #
  # Be "loose" to accommodate for future changes in list of currencies etc.
  #
  # @raise [InvalidCacheError] if cache is bogus.
  # @return [self]
  def reload
    time, quotations = cache_content

    @mutex.synchronize do
      @rates_date = time
      @currencies = quotations.map{|key, _| key}

      quotations.each do |currency, rate|
        set_rate('EUR', currency, rate, :without_mutex => true)
        set_rate(currency, 'EUR', 1/rate, :without_mutex => true)
      end

      quotations.product(quotations) do |one, another|
        one_cur, one_rate = one
        another_cur, another_rate = another
        next if one_cur == another_cur

        set_rate(one_cur, another_cur, another_rate/one_rate, :without_mutex => true)
      end
    end

    self
  end

  private

  # Read the cache and understand it.
  #
  # @return [[Time, Hash]]
  def cache_content
    csv = CSV.parse(@cache.get, :headers => true)
    csv = csv.first # Only one line.

    # Clean-up
    csv = csv.map{|key, value| [key.strip, value.strip]}
             .delete_if{|key, _| key.empty?}

    date_entry, *quotations = *csv
    _, date = date_entry

    time = Time.parse(date + ' ' + self.class.new_rates_time_of_day_s(date))
    quotations.map!{|cur,rate| [cur, BigDecimal.new(rate)]}

    [time, quotations]
  rescue
    raise InvalidCacheError
  end

  # Time of day (as a string ready for Time.parse) at which ECB publishes
  # new rates.
  #
  # @return [String] Either '13:00:00 UTC' or '14:00:00 UTC' depending on
  #   DST.
  def self.new_rates_time_of_day_s(date)
    # FIXME: It should be off by one day!

    # 15:00 ECB local time = 14:00 UTC when CET, 13:00 UTC when CEST.
    #
    # CEST:
    # - Starts in the morning of the last Sunday in March.
    # - Ends in the morning of the last Sunday in October.
    #
    # March  ...25  26  27  28  29  30  31
    #
    #          [Su] Mo  Tu  We  Th  Fr  Sa
    #           Sa [Su] Mo  Tu  We  Th  Fr
    #           Fr  Sa [Su] Mo  Tu  We  Th
    #           Th  Fr  Sa [Su] Mo  Tu  We
    #           We  Th  Fr  Sa [Su] Mo  Tu
    #           Tu  We  Th  Fr  Sa [Su] Mo
    #           Mo  Tu  We  Th  Fr  Sa [Su]
    #
    # October...25  26  27  28  29  30  31
    #
    # Where are we relative to the Sunday-diagonal?

    time = Time.parse(date)

    on = time.day >= 25 && time.sunday?
    above =
      (time.day == 26 && [1].include?(time.wday)) ||
      (time.day == 27 && [2,1].include?(time.wday)) ||
      (time.day == 28 && [3,2,1].include?(time.wday)) ||
      (time.day == 29 && [4,3,2,1].include?(time.wday)) ||
      (time.day == 30 && [5,4,3,2,1].include?(time.wday)) ||
      (time.day == 31 && [6,5,4,3,2,1].include?(time.wday))
    below =
      (time.day == 25 && [6,5,4,3,2,1].include?(time.wday)) ||
      (time.day == 26 && [6,5,4,3,2].include?(time.wday)) ||
      (time.day == 27 && [6,5,4,3].include?(time.wday)) ||
      (time.day == 28 && [6,5,4].include?(time.wday)) ||
      (time.day == 29 && [6,5].include?(time.wday)) ||
      (time.day == 30 && [6].include?(time.wday))

    cest = (4..9).include?(time.month) ||
      (time.month ==  3 && (on || above)) ||
      (time.month == 10 && (on || below))

    cest ? '13:00:00 UTC' : '14:00:00 UTC'
  end
end

#cache ⇒ Object (readonly)

The cache path and file name @return



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# File 'lib/money/bank/ecb.rb', line 34

class ECB < Money::Bank::VariableExchange
  # Error thrown when the cache file to be loaded isn't "good enough".
  class InvalidCacheError < StandardError; end

  RATES_URL = 'http://www.ecb.europa.eu/stats/eurofxref/eurofxref.zip'

  # Creates an Money::Bank::ECB.
  #
  # @param [String] cache_filename Absolute path and filename to the cache.
  #
  # @yield [x] Optional block to use for rounding after exchanging.
  # @yieldparam [Float] x The exchanged amount of cents to be rounded.
  # @yieldreturn [Integer]
  #
  # @return [Money::Bank::ECB]
  #
  # @example
  #   Money::Bank::ECB.new {|x| x.floor}
  #   #=> #<Money::Bank::ECB
  #         @rounding_method=#<Proc>,
  #         @auto_update=true,
  #         @rates=#<Hash>,
  #         @rates_date=#<Time>,
  #         @currencies=#<Array>>
  def initialize(cache = nil, &rounding_method)
    @cache = self.class.build(cache)
    super(&rounding_method)

    setup
  end

  # Builds a Cache from input.
  #
  # @param [*] something The thing to build a Cache from.
  # @return [Cache]
  def self.build(cache)
    case cache
    when Money::Bank::ECB::Cache
      cache
    when String
      Money::Bank::ECB::CacheFile.new(cache)
    else
      Money::Bank::ECB::SimpleCache.new
    end
  end

  attr_reader :cache
  attr_accessor :auto_update

  # Setup rates hash, mutex for rates locking, and auto_update default.
  #
  # @return [self]
  def setup
    @auto_update = true
    super
    reload rescue update
  end

  # Exchange some money
  #
  # @param [Money] from To exchange from.
  # @param [String,Symbol] to Currency to exchange to.
  # @yield [x] Optional block to use for rounding after exchanging.
  # @yieldparam [Float] x The exchanged amount of cents to be rounded.
  # @yieldreturn [Integer]
  #
  # @return [Money]
  #
  # @example
  #   ecb.exchange_with(Money.new(100, :EUR), :USD)
  def exchange_with(from, to, &rounding_method)
    update if @auto_update and Time.now.utc > (@rates_date + 60*60*24)
    super(from, to, &rounding_method)
  end

  # Update the cache file and load the new rates.
  #
  # This is only relevant if #auto_update is false.
  #
  # @return [self]
  def update
    update_cache
    reload

    self
  end

  # Update the cache.
  #
  # @return [self]
  def update_cache
    Zip::InputStream.open(open(RATES_URL)) do |io|
      io.get_next_entry
      @cache.set(io.read)
    end

    self
  end

  attr_reader :currencies
  attr_reader :rates_date

  # Load rates from the cache file.
  #
  # Be "loose" to accommodate for future changes in list of currencies etc.
  #
  # @raise [InvalidCacheError] if cache is bogus.
  # @return [self]
  def reload
    time, quotations = cache_content

    @mutex.synchronize do
      @rates_date = time
      @currencies = quotations.map{|key, _| key}

      quotations.each do |currency, rate|
        set_rate('EUR', currency, rate, :without_mutex => true)
        set_rate(currency, 'EUR', 1/rate, :without_mutex => true)
      end

      quotations.product(quotations) do |one, another|
        one_cur, one_rate = one
        another_cur, another_rate = another
        next if one_cur == another_cur

        set_rate(one_cur, another_cur, another_rate/one_rate, :without_mutex => true)
      end
    end

    self
  end

  private

  # Read the cache and understand it.
  #
  # @return [[Time, Hash]]
  def cache_content
    csv = CSV.parse(@cache.get, :headers => true)
    csv = csv.first # Only one line.

    # Clean-up
    csv = csv.map{|key, value| [key.strip, value.strip]}
             .delete_if{|key, _| key.empty?}

    date_entry, *quotations = *csv
    _, date = date_entry

    time = Time.parse(date + ' ' + self.class.new_rates_time_of_day_s(date))
    quotations.map!{|cur,rate| [cur, BigDecimal.new(rate)]}

    [time, quotations]
  rescue
    raise InvalidCacheError
  end

  # Time of day (as a string ready for Time.parse) at which ECB publishes
  # new rates.
  #
  # @return [String] Either '13:00:00 UTC' or '14:00:00 UTC' depending on
  #   DST.
  def self.new_rates_time_of_day_s(date)
    # FIXME: It should be off by one day!

    # 15:00 ECB local time = 14:00 UTC when CET, 13:00 UTC when CEST.
    #
    # CEST:
    # - Starts in the morning of the last Sunday in March.
    # - Ends in the morning of the last Sunday in October.
    #
    # March  ...25  26  27  28  29  30  31
    #
    #          [Su] Mo  Tu  We  Th  Fr  Sa
    #           Sa [Su] Mo  Tu  We  Th  Fr
    #           Fr  Sa [Su] Mo  Tu  We  Th
    #           Th  Fr  Sa [Su] Mo  Tu  We
    #           We  Th  Fr  Sa [Su] Mo  Tu
    #           Tu  We  Th  Fr  Sa [Su] Mo
    #           Mo  Tu  We  Th  Fr  Sa [Su]
    #
    # October...25  26  27  28  29  30  31
    #
    # Where are we relative to the Sunday-diagonal?

    time = Time.parse(date)

    on = time.day >= 25 && time.sunday?
    above =
      (time.day == 26 && [1].include?(time.wday)) ||
      (time.day == 27 && [2,1].include?(time.wday)) ||
      (time.day == 28 && [3,2,1].include?(time.wday)) ||
      (time.day == 29 && [4,3,2,1].include?(time.wday)) ||
      (time.day == 30 && [5,4,3,2,1].include?(time.wday)) ||
      (time.day == 31 && [6,5,4,3,2,1].include?(time.wday))
    below =
      (time.day == 25 && [6,5,4,3,2,1].include?(time.wday)) ||
      (time.day == 26 && [6,5,4,3,2].include?(time.wday)) ||
      (time.day == 27 && [6,5,4,3].include?(time.wday)) ||
      (time.day == 28 && [6,5,4].include?(time.wday)) ||
      (time.day == 29 && [6,5].include?(time.wday)) ||
      (time.day == 30 && [6].include?(time.wday))

    cest = (4..9).include?(time.month) ||
      (time.month ==  3 && (on || above)) ||
      (time.month == 10 && (on || below))

    cest ? '13:00:00 UTC' : '14:00:00 UTC'
  end
end

#currencies ⇒ Array<String> (readonly)

The available currencies to exchange between.



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# File 'lib/money/bank/ecb.rb', line 34

class ECB < Money::Bank::VariableExchange
  # Error thrown when the cache file to be loaded isn't "good enough".
  class InvalidCacheError < StandardError; end

  RATES_URL = 'http://www.ecb.europa.eu/stats/eurofxref/eurofxref.zip'

  # Creates an Money::Bank::ECB.
  #
  # @param [String] cache_filename Absolute path and filename to the cache.
  #
  # @yield [x] Optional block to use for rounding after exchanging.
  # @yieldparam [Float] x The exchanged amount of cents to be rounded.
  # @yieldreturn [Integer]
  #
  # @return [Money::Bank::ECB]
  #
  # @example
  #   Money::Bank::ECB.new {|x| x.floor}
  #   #=> #<Money::Bank::ECB
  #         @rounding_method=#<Proc>,
  #         @auto_update=true,
  #         @rates=#<Hash>,
  #         @rates_date=#<Time>,
  #         @currencies=#<Array>>
  def initialize(cache = nil, &rounding_method)
    @cache = self.class.build(cache)
    super(&rounding_method)

    setup
  end

  # Builds a Cache from input.
  #
  # @param [*] something The thing to build a Cache from.
  # @return [Cache]
  def self.build(cache)
    case cache
    when Money::Bank::ECB::Cache
      cache
    when String
      Money::Bank::ECB::CacheFile.new(cache)
    else
      Money::Bank::ECB::SimpleCache.new
    end
  end

  attr_reader :cache
  attr_accessor :auto_update

  # Setup rates hash, mutex for rates locking, and auto_update default.
  #
  # @return [self]
  def setup
    @auto_update = true
    super
    reload rescue update
  end

  # Exchange some money
  #
  # @param [Money] from To exchange from.
  # @param [String,Symbol] to Currency to exchange to.
  # @yield [x] Optional block to use for rounding after exchanging.
  # @yieldparam [Float] x The exchanged amount of cents to be rounded.
  # @yieldreturn [Integer]
  #
  # @return [Money]
  #
  # @example
  #   ecb.exchange_with(Money.new(100, :EUR), :USD)
  def exchange_with(from, to, &rounding_method)
    update if @auto_update and Time.now.utc > (@rates_date + 60*60*24)
    super(from, to, &rounding_method)
  end

  # Update the cache file and load the new rates.
  #
  # This is only relevant if #auto_update is false.
  #
  # @return [self]
  def update
    update_cache
    reload

    self
  end

  # Update the cache.
  #
  # @return [self]
  def update_cache
    Zip::InputStream.open(open(RATES_URL)) do |io|
      io.get_next_entry
      @cache.set(io.read)
    end

    self
  end

  attr_reader :currencies
  attr_reader :rates_date

  # Load rates from the cache file.
  #
  # Be "loose" to accommodate for future changes in list of currencies etc.
  #
  # @raise [InvalidCacheError] if cache is bogus.
  # @return [self]
  def reload
    time, quotations = cache_content

    @mutex.synchronize do
      @rates_date = time
      @currencies = quotations.map{|key, _| key}

      quotations.each do |currency, rate|
        set_rate('EUR', currency, rate, :without_mutex => true)
        set_rate(currency, 'EUR', 1/rate, :without_mutex => true)
      end

      quotations.product(quotations) do |one, another|
        one_cur, one_rate = one
        another_cur, another_rate = another
        next if one_cur == another_cur

        set_rate(one_cur, another_cur, another_rate/one_rate, :without_mutex => true)
      end
    end

    self
  end

  private

  # Read the cache and understand it.
  #
  # @return [[Time, Hash]]
  def cache_content
    csv = CSV.parse(@cache.get, :headers => true)
    csv = csv.first # Only one line.

    # Clean-up
    csv = csv.map{|key, value| [key.strip, value.strip]}
             .delete_if{|key, _| key.empty?}

    date_entry, *quotations = *csv
    _, date = date_entry

    time = Time.parse(date + ' ' + self.class.new_rates_time_of_day_s(date))
    quotations.map!{|cur,rate| [cur, BigDecimal.new(rate)]}

    [time, quotations]
  rescue
    raise InvalidCacheError
  end

  # Time of day (as a string ready for Time.parse) at which ECB publishes
  # new rates.
  #
  # @return [String] Either '13:00:00 UTC' or '14:00:00 UTC' depending on
  #   DST.
  def self.new_rates_time_of_day_s(date)
    # FIXME: It should be off by one day!

    # 15:00 ECB local time = 14:00 UTC when CET, 13:00 UTC when CEST.
    #
    # CEST:
    # - Starts in the morning of the last Sunday in March.
    # - Ends in the morning of the last Sunday in October.
    #
    # March  ...25  26  27  28  29  30  31
    #
    #          [Su] Mo  Tu  We  Th  Fr  Sa
    #           Sa [Su] Mo  Tu  We  Th  Fr
    #           Fr  Sa [Su] Mo  Tu  We  Th
    #           Th  Fr  Sa [Su] Mo  Tu  We
    #           We  Th  Fr  Sa [Su] Mo  Tu
    #           Tu  We  Th  Fr  Sa [Su] Mo
    #           Mo  Tu  We  Th  Fr  Sa [Su]
    #
    # October...25  26  27  28  29  30  31
    #
    # Where are we relative to the Sunday-diagonal?

    time = Time.parse(date)

    on = time.day >= 25 && time.sunday?
    above =
      (time.day == 26 && [1].include?(time.wday)) ||
      (time.day == 27 && [2,1].include?(time.wday)) ||
      (time.day == 28 && [3,2,1].include?(time.wday)) ||
      (time.day == 29 && [4,3,2,1].include?(time.wday)) ||
      (time.day == 30 && [5,4,3,2,1].include?(time.wday)) ||
      (time.day == 31 && [6,5,4,3,2,1].include?(time.wday))
    below =
      (time.day == 25 && [6,5,4,3,2,1].include?(time.wday)) ||
      (time.day == 26 && [6,5,4,3,2].include?(time.wday)) ||
      (time.day == 27 && [6,5,4,3].include?(time.wday)) ||
      (time.day == 28 && [6,5,4].include?(time.wday)) ||
      (time.day == 29 && [6,5].include?(time.wday)) ||
      (time.day == 30 && [6].include?(time.wday))

    cest = (4..9).include?(time.month) ||
      (time.month ==  3 && (on || above)) ||
      (time.month == 10 && (on || below))

    cest ? '13:00:00 UTC' : '14:00:00 UTC'
  end
end

#rates_date ⇒ Object (readonly)

The time on which ECB published the rates that is currently in use. @return



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# File 'lib/money/bank/ecb.rb', line 34

class ECB < Money::Bank::VariableExchange
  # Error thrown when the cache file to be loaded isn't "good enough".
  class InvalidCacheError < StandardError; end

  RATES_URL = 'http://www.ecb.europa.eu/stats/eurofxref/eurofxref.zip'

  # Creates an Money::Bank::ECB.
  #
  # @param [String] cache_filename Absolute path and filename to the cache.
  #
  # @yield [x] Optional block to use for rounding after exchanging.
  # @yieldparam [Float] x The exchanged amount of cents to be rounded.
  # @yieldreturn [Integer]
  #
  # @return [Money::Bank::ECB]
  #
  # @example
  #   Money::Bank::ECB.new {|x| x.floor}
  #   #=> #<Money::Bank::ECB
  #         @rounding_method=#<Proc>,
  #         @auto_update=true,
  #         @rates=#<Hash>,
  #         @rates_date=#<Time>,
  #         @currencies=#<Array>>
  def initialize(cache = nil, &rounding_method)
    @cache = self.class.build(cache)
    super(&rounding_method)

    setup
  end

  # Builds a Cache from input.
  #
  # @param [*] something The thing to build a Cache from.
  # @return [Cache]
  def self.build(cache)
    case cache
    when Money::Bank::ECB::Cache
      cache
    when String
      Money::Bank::ECB::CacheFile.new(cache)
    else
      Money::Bank::ECB::SimpleCache.new
    end
  end

  attr_reader :cache
  attr_accessor :auto_update

  # Setup rates hash, mutex for rates locking, and auto_update default.
  #
  # @return [self]
  def setup
    @auto_update = true
    super
    reload rescue update
  end

  # Exchange some money
  #
  # @param [Money] from To exchange from.
  # @param [String,Symbol] to Currency to exchange to.
  # @yield [x] Optional block to use for rounding after exchanging.
  # @yieldparam [Float] x The exchanged amount of cents to be rounded.
  # @yieldreturn [Integer]
  #
  # @return [Money]
  #
  # @example
  #   ecb.exchange_with(Money.new(100, :EUR), :USD)
  def exchange_with(from, to, &rounding_method)
    update if @auto_update and Time.now.utc > (@rates_date + 60*60*24)
    super(from, to, &rounding_method)
  end

  # Update the cache file and load the new rates.
  #
  # This is only relevant if #auto_update is false.
  #
  # @return [self]
  def update
    update_cache
    reload

    self
  end

  # Update the cache.
  #
  # @return [self]
  def update_cache
    Zip::InputStream.open(open(RATES_URL)) do |io|
      io.get_next_entry
      @cache.set(io.read)
    end

    self
  end

  attr_reader :currencies
  attr_reader :rates_date

  # Load rates from the cache file.
  #
  # Be "loose" to accommodate for future changes in list of currencies etc.
  #
  # @raise [InvalidCacheError] if cache is bogus.
  # @return [self]
  def reload
    time, quotations = cache_content

    @mutex.synchronize do
      @rates_date = time
      @currencies = quotations.map{|key, _| key}

      quotations.each do |currency, rate|
        set_rate('EUR', currency, rate, :without_mutex => true)
        set_rate(currency, 'EUR', 1/rate, :without_mutex => true)
      end

      quotations.product(quotations) do |one, another|
        one_cur, one_rate = one
        another_cur, another_rate = another
        next if one_cur == another_cur

        set_rate(one_cur, another_cur, another_rate/one_rate, :without_mutex => true)
      end
    end

    self
  end

  private

  # Read the cache and understand it.
  #
  # @return [[Time, Hash]]
  def cache_content
    csv = CSV.parse(@cache.get, :headers => true)
    csv = csv.first # Only one line.

    # Clean-up
    csv = csv.map{|key, value| [key.strip, value.strip]}
             .delete_if{|key, _| key.empty?}

    date_entry, *quotations = *csv
    _, date = date_entry

    time = Time.parse(date + ' ' + self.class.new_rates_time_of_day_s(date))
    quotations.map!{|cur,rate| [cur, BigDecimal.new(rate)]}

    [time, quotations]
  rescue
    raise InvalidCacheError
  end

  # Time of day (as a string ready for Time.parse) at which ECB publishes
  # new rates.
  #
  # @return [String] Either '13:00:00 UTC' or '14:00:00 UTC' depending on
  #   DST.
  def self.new_rates_time_of_day_s(date)
    # FIXME: It should be off by one day!

    # 15:00 ECB local time = 14:00 UTC when CET, 13:00 UTC when CEST.
    #
    # CEST:
    # - Starts in the morning of the last Sunday in March.
    # - Ends in the morning of the last Sunday in October.
    #
    # March  ...25  26  27  28  29  30  31
    #
    #          [Su] Mo  Tu  We  Th  Fr  Sa
    #           Sa [Su] Mo  Tu  We  Th  Fr
    #           Fr  Sa [Su] Mo  Tu  We  Th
    #           Th  Fr  Sa [Su] Mo  Tu  We
    #           We  Th  Fr  Sa [Su] Mo  Tu
    #           Tu  We  Th  Fr  Sa [Su] Mo
    #           Mo  Tu  We  Th  Fr  Sa [Su]
    #
    # October...25  26  27  28  29  30  31
    #
    # Where are we relative to the Sunday-diagonal?

    time = Time.parse(date)

    on = time.day >= 25 && time.sunday?
    above =
      (time.day == 26 && [1].include?(time.wday)) ||
      (time.day == 27 && [2,1].include?(time.wday)) ||
      (time.day == 28 && [3,2,1].include?(time.wday)) ||
      (time.day == 29 && [4,3,2,1].include?(time.wday)) ||
      (time.day == 30 && [5,4,3,2,1].include?(time.wday)) ||
      (time.day == 31 && [6,5,4,3,2,1].include?(time.wday))
    below =
      (time.day == 25 && [6,5,4,3,2,1].include?(time.wday)) ||
      (time.day == 26 && [6,5,4,3,2].include?(time.wday)) ||
      (time.day == 27 && [6,5,4,3].include?(time.wday)) ||
      (time.day == 28 && [6,5,4].include?(time.wday)) ||
      (time.day == 29 && [6,5].include?(time.wday)) ||
      (time.day == 30 && [6].include?(time.wday))

    cest = (4..9).include?(time.month) ||
      (time.month ==  3 && (on || above)) ||
      (time.month == 10 && (on || below))

    cest ? '13:00:00 UTC' : '14:00:00 UTC'
  end
end

Class Method Details

.build(cache) ⇒ Cache

Builds a Cache from input.



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# File 'lib/money/bank/ecb.rb', line 69

def self.build(cache)
  case cache
  when Money::Bank::ECB::Cache
    cache
  when String
    Money::Bank::ECB::CacheFile.new(cache)
  else
    Money::Bank::ECB::SimpleCache.new
  end
end

Instance Method Details

#exchange_with(from, to) {|x| ... } ⇒ Money

Exchange some money

Examples:

ecb.exchange_with(Money.new(100, :EUR), :USD)

Yields:

  • (x) —

    Optional block to use for rounding after exchanging.

Yield Parameters:

  • x (Float) —

    The exchanged amount of cents to be rounded.

Yield Returns:

  • (Integer) 


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# File 'lib/money/bank/ecb.rb', line 104

def exchange_with(from, to, &rounding_method)
  update if @auto_update and Time.now.utc > (@rates_date + 60*60*24)
  super(from, to, &rounding_method)
end

#reload ⇒ self

Load rates from the cache file.

Be “loose” to accommodate for future changes in list of currencies etc.

Raises:



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# File 'lib/money/bank/ecb.rb', line 142

def reload
  time, quotations = cache_content

  @mutex.synchronize do
    @rates_date = time
    @currencies = quotations.map{|key, _| key}

    quotations.each do |currency, rate|
      set_rate('EUR', currency, rate, :without_mutex => true)
      set_rate(currency, 'EUR', 1/rate, :without_mutex => true)
    end

    quotations.product(quotations) do |one, another|
      one_cur, one_rate = one
      another_cur, another_rate = another
      next if one_cur == another_cur

      set_rate(one_cur, another_cur, another_rate/one_rate, :without_mutex => true)
    end
  end

  self
end

#setup ⇒ self

Setup rates hash, mutex for rates locking, and auto_update default.



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# File 'lib/money/bank/ecb.rb', line 86

def setup
  @auto_update = true
  super
  reload rescue update
end

#update ⇒ self

Update the cache file and load the new rates.

This is only relevant if #auto_update is false.



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# File 'lib/money/bank/ecb.rb', line 114

def update
  update_cache
  reload

  self
end

#update_cache ⇒ self

Update the cache.



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# File 'lib/money/bank/ecb.rb', line 124

def update_cache
  Zip::InputStream.open(open(RATES_URL)) do |io|
    io.get_next_entry
    @cache.set(io.read)
  end

  self
end