113 lines
3.1 KiB
Ruby
113 lines
3.1 KiB
Ruby
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# frozen_string_literal: true
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require "json"
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require "net/http"
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require "provider/adapters/adapter"
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class Provider
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module Adapters
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# Bank of Jamaica daily counter rates in JMD.
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# Fetches from a WPDataTables endpoint (table_id=134), which requires a nonce extracted from the page HTML.
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class BOJA < Adapter
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PAGE_URL = "https://boj.org.jm/market/foreign-exchange/counter-rates/"
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BASE_URL = "https://boj.org.jm/wp-admin/admin-ajax.php"
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TABLE_ID = 134
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NONCE_PATTERN = /wdtNonceFrontendServerSide_#{TABLE_ID}"\s+value="([^"]+)"/
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CURRENCY_MAP = {
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"U.S. DOLLAR" => "USD",
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"GREAT BRITAIN POUND" => "GBP",
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"CANADA DOLLAR" => "CAD",
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"EURO" => "EUR",
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"JAPANESE YEN" => "JPY",
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"SWISS FRANC" => "CHF",
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"AUSTRALIAN DOLLAR" => "AUD",
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"DANISH KRONE" => "DKK",
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"NORWEGIAN KRONE" => "NOK",
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"SWEDISH KRONA" => "SEK",
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"HONG KONG DOLLAR" => "HKD",
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"BARBADOS DOLLAR" => "BBD",
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"BELIZE DOLLAR" => "BZD",
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"T&T DOLLAR" => "TTD",
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"BAHAMAS DOLLAR" => "BSD",
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"CAYMAN DOLLAR" => "KYD",
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"GUYANA DOLLAR" => "GYD",
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"E. C. DOLLAR" => "XCD",
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"DOMINICAN REP. PESO" => "DOP",
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"GIBRALTAR POUND" => "GIP",
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"NORTHERN IRELAND POUND" => "GBP",
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}.freeze
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def fetch(after: nil, upto: nil)
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dataset = fetch_table
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dataset = dataset.select { |r| r[:date] >= after } if after
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dataset = dataset.select { |r| r[:date] <= upto } if upto
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dataset
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end
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def parse(json)
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data = json.is_a?(String) ? JSON.parse(json) : json
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rows = data["data"]
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return [] unless rows.is_a?(Array)
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rows.filter_map do |row|
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parse_row(row)
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end
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end
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private
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def fetch_table
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nonce = fetch_nonce
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return [] unless nonce
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uri = URI("#{BASE_URL}?action=get_wdtable&table_id=#{TABLE_ID}")
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request = Net::HTTP::Post.new(uri)
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request.set_form_data("draw" => "1", "start" => "0", "length" => "-1", "wdtNonce" => nonce)
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response = Net::HTTP.start(uri.hostname, uri.port, use_ssl: true) do |http|
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http.request(request)
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end
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parse(response.body)
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end
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def fetch_nonce
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uri = URI(PAGE_URL)
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response = Net::HTTP.get(uri)
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match = response.match(NONCE_PATTERN)
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match&.captures&.first
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end
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def parse_row(row)
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date_str, currency_name, sell_rate, buy_rate, = row
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return unless date_str && currency_name
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date = Date.strptime(date_str.strip, "%d %b %Y")
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iso = resolve_currency(currency_name.strip)
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return unless iso
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rate_value = compute_mid(sell_rate, buy_rate)
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return unless rate_value && !rate_value.zero?
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{ date:, base: iso, quote: "JMD", rate: rate_value }
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end
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def compute_mid(sell, buy)
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s = Float(sell)
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b = Float(buy)
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return s if b.zero?
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(s + b) / 2.0
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end
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def resolve_currency(name)
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CURRENCY_MAP[name.upcase]
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end
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end
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end
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end
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