Merge pull request #1889 from trade-tariff/ott-309

Monkey patch for allowing ZWL rate only be saved as ZIG

Gemfile.lock

@@ -521,7 +521,7 @@ DEPENDENCIES
   webmock
 
 RUBY VERSION
-   ruby 3.2.2p53
+   ruby 3.2.3p157
 
 BUNDLED WITH
    2.3.8

app/services/exchange_rates/update_currency_rates_service.rb

@@ -13,17 +13,26 @@ def call
       response = @xe_api.get_all_historic_rates
 
       ExchangeRateCurrencyRate.db.transaction do
-        rates = build_rates(response)
-        # This will only get rates for the current live rates so you cant pull historic data
-        included_rates = @type == ExchangeRateCurrencyRate::MONTHLY_RATE_TYPE ? ExchangeRateCountryCurrency.live_currency_codes : ExchangeRateCountryCurrency::SPOT_RATE_CURRENCY_CODES
-        rates = rates.select { |rate| included_rates.include?(rate.currency_code) }
-
+        rates = build_rates(response).select { |rate| included_rates.include?(rate.currency_code) }
         upsert_rates(rates)
       end
     end
 
     private
 
+    def monthly_rate_type?
+      @type == ExchangeRateCurrencyRate::MONTHLY_RATE_TYPE
+    end
+
+    def included_rates
+      # This will only get rates for the current live rates so you cant pull historic data
+      if monthly_rate_type?
+        ExchangeRateCountryCurrency.live_currency_codes
+      else
+        ExchangeRateCountryCurrency::SPOT_RATE_CURRENCY_CODES
+      end
+    end
+
     def build_rates(response)
       response['to'].map do |currency_data|
         build_rate(currency_data)
@@ -41,16 +50,24 @@ def build_rate(currency_data)
       currency_code = currency_data['quotecurrency']
       rate = currency_data['mid']
 
-      validity_start_date = @type == ExchangeRateCurrencyRate::MONTHLY_RATE_TYPE ? @date.beginning_of_month : @date.end_of_month
+      validity_start_date = monthly_rate_type? ? @date.beginning_of_month : @date.end_of_month
       validity_end_date = @date.end_of_month
 
       ExchangeRateCurrencyRate.new(
-        currency_code:,
+        currency_code: currency_overide(currency_code),
         validity_start_date:,
         validity_end_date:,
         rate:,
         rate_type: @type,
       )
     end
+
+    def currency_overide(currency_code)
+      currency_overides = { 'ZWL' => 'ZIG' }
+
+      return currency_code unless currency_overides.keys.include?(currency_code)
+
+      currency_overides[currency_code]
+    end
   end
 end

db/data_migrations/20240606125159_add_new_zimbabwe_gold.rb

@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+Sequel.migration do
+  up do
+    if TradeTariffBackend.uk?
+      new_zimbabwe_country_currency = ExchangeRateCountryCurrency.where(country_description: 'Zimbabwe',
+                                                                        currency_code: 'ZIG',
+                                                                        country_code:'ZW').first
+
+      zimbabwe_country_currency.update(country_description: 'Zimbabwe Gold')
+    end
+  end
+
+  down do
+    # We don't want to rollback to incorrect Zimbabwe rates.
+  end
+end

spec/services/exchange_rates/update_currency_rates_service_spec.rb

@@ -45,8 +45,23 @@
       let(:sample_date) { Time.zone.today }
 
       before do
-        create(:exchange_rate_country_currency, currency_code: 'AED')
-        create(:exchange_rate_country_currency, currency_code: 'EUR')
+        create(:exchange_rate_country_currency,
+               country_code: 'AE',
+               country_description: 'UAE',
+               currency_description: 'Dirham',
+               currency_code: 'AED')
+        create(:exchange_rate_country_currency,
+               country_code: 'EU',
+               country_description: 'Eurozone',
+               currency_description: 'Euro',
+               currency_code: 'EUR')
+
+        # Only added for the Zimbabwe monkey patch situation
+        create(:exchange_rate_country_currency,
+               country_code: 'ZW',
+               country_description: 'Zimbabwe',
+               currency_description: 'Zimbabwe Gold',
+               currency_code: 'ZIG')
       end
 
       it 'only inserts rates that exist as currencies' do
@@ -60,6 +75,69 @@
 
         expect(new_rates).to include_json(expected_rates)
       end
+
+      # Below test is in place to protect us against XE
+      # not porviding ZIG currnecy even though its accepted across over 90% banks in Zimbabwe
+      context 'when XE provides ZWL and ZIG' do
+        let(:response) do
+          {
+            'to' => [
+              { 'quotecurrency' => 'ZWL', 'mid' => 16.8567 },
+              { 'quotecurrency' => 'ZIG', 'mid' => 16.8567 },
+            ],
+          }
+        end
+
+        let(:expected_rates) do
+          [
+            {
+              currency_code: 'ZIG',
+              validity_start_date: date.beginning_of_month,
+              validity_end_date: date.end_of_month,
+              rate: 16.8567,
+              rate_type: ExchangeRateCurrencyRate::MONTHLY_RATE_TYPE,
+            },
+          ].as_json
+        end
+
+        it 'will create a ZIG rate' do
+          service.call
+
+          new_rates = ExchangeRateCurrencyRate.all.map(&:values).as_json
+
+          expect(new_rates).to include_json(expected_rates)
+        end
+      end
+
+      context 'when XE provides ZWL' do
+        let(:response) do
+          {
+            'to' => [
+              { 'quotecurrency' => 'ZWL', 'mid' => 16.8567 },
+            ],
+          }
+        end
+
+        let(:expected_rates) do
+          [
+            {
+              currency_code: 'ZIG',
+              validity_start_date: date.beginning_of_month,
+              validity_end_date: date.end_of_month,
+              rate: 16.8567,
+              rate_type: ExchangeRateCurrencyRate::MONTHLY_RATE_TYPE,
+            },
+          ].as_json
+        end
+
+        it 'will create a ZIG rate' do
+          service.call
+
+          new_rates = ExchangeRateCurrencyRate.all.map(&:values).as_json
+
+          expect(new_rates).to include_json(expected_rates)
+        end
+      end
     end
 
     context 'when type is SPOT_RATE_TYPE' do