Fetch EasyEnergy prices (for openhab-jruby)

easyenergy.rb

# Group   EnergyMarkets               "Energy Markets"
# Group   NaturalGasMarketPrices      "Natural Gas"                            (EnergyMarkets)
# Group   EnergyMarketPrices          "Energy"                                 (EnergyMarkets)

# Number  EnergyPrice                 "Energy Price [%.3f €/kWh]"              (EnergyMarketPrices)
# Number  EnergyBasePrice             "Energy Base Price [%.3f €/kWh]"         (EnergyMarketPrices)
# Number  EnergyProcurementSurcharge  "Energy Procurement Price [%.3f €/kWh]"  (EnergyMarketPrices)
# Number  EnergyTaxSurcharge          "Energy Tax Surcharge [%.3f €/kWh]"      (EnergyMarketPrices)
# Number  EnergyGreenSurcharge        "Energy Green Surcharge [%.3f €/kWh]"    (EnergyMarketPrices)

# Number  GasPrice                    "Gas Price [%.3f €/m³]"                  (NaturalGasMarketPrices)
# Number  GasBasePrice                "Gas Base Price [%.3f €/m³]"             (NaturalGasMarketPrices)
# Number  GasProcurementSurcharge     "Gas Procurement Price [%.3f €/kWh]"     (NaturalGasMarketPrices)
# Number  GasTaxSurcharge             "Gas Tax Surcharge [%.3f €/m³]"          (NaturalGasMarketPrices)
# Number  GasRegionalTax              "Gas Regional Tax [%.3f €/m³]"           (NaturalGasMarketPrices)

begin
  debug = false

  gemfile do
    source "https://rubygems.org"
    gem "json", "~> 2.6", require: true
    gem "nokogiri", "~> 1.15", require: true
    gem "open-uri", "~> 0.3.0", require: true
  end

  def url_open(url)
    logger.info("Downloading #{url}")
    URI.open(url)
  end

  def cache_file(name)
    "/cache/#{name}.json"
  end

  def download(url, target)
    File.write(cache_file(target), url_open(url).string)
  end

  def fetch(target)
    JSON.load File.read(cache_file(target))
  end

  require "cgi"

  url_prefix = (debug ? "http://192.168.88.254:8000" : "https://mijn.easyenergy.com/nl")

  #url_prefix  = "/api/tariff"
  markets     = {
    :gas    => "leba",
    :energy => "apx"
  }

  [:gas, :energy].each do |target|
    mark = target.to_s

    rule "Fetch daily #{mark} prices" do
      on_load

      every :day, at: "06:30"
      every :day, at: "15:30"

      run do
        market     = markets[target]
        start      = DateTime.now.new_offset(0) - 1/24r  # subtract an hour
        finish     = start + 1                           # add a day
        url        = url_prefix + (debug ? "" : "/api/tariff")
        url        = "#{url}/get%stariffs?startTimestamp=%s&endTimestamp=%s&grouping=&includeVat=true" \
                   % [market, start, finish].map { |c| CGI.escape(c.to_s) }

        download(url, mark)
      end
    end

    rule "Set hourly #{mark} price" do
      on_load

      every :hour

      run do
        tag       = (target == :gas ? GasBasePrice : EnergyBasePrice)
        finish    = DateTime.now.new_offset(0)
        start     = finish - 1/24r
        document  = fetch(mark)

        if document.length > 0
          prices = document.select do |price|
            (start..finish).cover? DateTime.parse(price["Timestamp"])
          end

          unless prices.length > 0
            raise "No price available for #{mark} between #{start} and #{finish}"
          end

          tag << prices.first["TariffUsage"].to_f
        else
          raise "No prices available for #{mark}"
        end
      end
    end
  end

  rule "Fetch surcharges for energy & gas" do
    every :day

    run do
      document    = Nokogiri::HTML url_open("#{url_prefix}/energietarieven")
      xpath       = "/html/body/div[4]/div/div/div/p[2]/text()[%s]"
      surcharges  = {
        "EnergyProcurementSurcharge"    => xpath % 5,
        "EnergyTaxSurcharge"            => xpath % 6,
        "EnergyGreenSurcharge"          => xpath % 7,
        "GasProcurementSurcharge"       => xpath % 8,
        "GasTaxSurcharge"               => xpath % 9,
        "GasRegionalTax"                => xpath % 10
      }

      surcharges.each do |surcharge, path|
        document.xpath(path).each do |line|
          line  = line.content.gsub(",", ".")
          price = line.match(/\d+.\d+ ct/).values_at(0).first.to_f / 100

          items[surcharge] << price.truncate(5)
        end
      end
    end
  end

rescue => details
  error = "easy-energy.rb: #{details.full_message}"
  logger.warn(error)
  notify(error)
end