add dydx orderbook

lib/cryptoexchange/exchanges/dydx/market.rb

@@ -2,7 +2,7 @@ module Cryptoexchange::Exchanges
   module Dydx
     class Market < Cryptoexchange::Models::Market
       NAME = 'dydx'
-      API_URL = 'https://api.dydx.exchange/v1/stats/markets'
+      API_URL = 'https://api.dydx.exchange/v1'
 
       def self.trade_page_url(args={})
         "https://trade.dydx.exchange/markets"

lib/cryptoexchange/exchanges/dydx/services/market.rb

@@ -14,7 +14,7 @@ def fetch
         end
 
         def ticker_url
-          "#{Cryptoexchange::Exchanges::Dydx::Market::API_URL}"
+          "#{Cryptoexchange::Exchanges::Dydx::Market::API_URL}/stats/markets"
         end
 
 

lib/cryptoexchange/exchanges/dydx/services/order_book.rb

@@ -0,0 +1,46 @@
+module Cryptoexchange::Exchanges
+  module Dydx
+    module Services
+      class OrderBook < Cryptoexchange::Services::Market
+        class << self
+          def supports_individual_ticker_query?
+            true
+          end
+        end
+
+        def fetch(market_pair)
+          puts ticker_url(market_pair)
+          output = super(ticker_url(market_pair))
+          adapt(output, market_pair)
+        end
+
+        def ticker_url(market_pair)
+          base   = market_pair.base
+          target = market_pair.target
+          "#{Cryptoexchange::Exchanges::Dydx::Market::API_URL}/orderbook/#{base}-#{target}"
+        end
+
+        def adapt(output, market_pair)
+          order_book = Cryptoexchange::Models::OrderBook.new
+
+          order_book.base      = market_pair.base
+          order_book.target    = market_pair.target
+          order_book.market    = Dydx::Market::NAME
+          order_book.asks      = adapt_orders(output['bids'])
+          order_book.bids      = adapt_orders(output['asks'])
+          order_book.timestamp = nil
+          order_book.payload   = output
+          order_book
+        end
+
+        def adapt_orders(orders)
+          orders.collect do |order_entry|
+            Cryptoexchange::Models::Order.new(price:     order_entry['price'],
+                                              amount:    order_entry['amount'].to_f,
+                                              timestamp: nil)
+          end
+        end
+      end
+    end
+  end
+end

lib/cryptoexchange/exchanges/dydx/services/pairs.rb

@@ -2,7 +2,7 @@ module Cryptoexchange::Exchanges
   module Dydx
     module Services
       class Pairs < Cryptoexchange::Services::Pairs
-        PAIRS_URL = "#{Cryptoexchange::Exchanges::Dydx::Market::API_URL}"
+        PAIRS_URL = "#{Cryptoexchange::Exchanges::Dydx::Market::API_URL}/stats/markets"
 
         def fetch
           output = super

spec/exchanges/dydx/market_spec.rb

@@ -2,5 +2,5 @@
 
 RSpec.describe Cryptoexchange::Exchanges::Dydx::Market do
   it { expect(described_class::NAME).to eq 'dydx' }
-  it { expect(described_class::API_URL).to eq 'https://api.dydx.exchange/v1/stats/markets' }
+  it { expect(described_class::API_URL).to eq 'https://api.dydx.exchange/v1' }
 end