Simplify exhange rate backend

InvenTree/InvenTree/exchange.py

@@ -1,120 +1,29 @@
 from django.conf import settings as inventree_settings
 
-from djmoney.contrib.exchange.backends.base import BaseExchangeBackend
+from djmoney.contrib.exchange.backends.base import SimpleExchangeBackend
-from djmoney.contrib.exchange.models import Rate
-
-from common.models import InvenTreeSetting
 
 
-def get_exchange_rate_backend():
+class InvenTreeExchange(SimpleExchangeBackend):
-    """ Return the exchange rate backend set by user """
-
-    custom = InvenTreeSetting.get_setting('CUSTOM_EXCHANGE_RATES', False)
-
-    if custom:
-        return InvenTreeManualExchangeBackend()
-    else:
-        return ExchangeRateHostBackend()
-
-
-class InvenTreeManualExchangeBackend(BaseExchangeBackend):
     """
-    Backend for manually updating currency exchange rates
+    Backend for automatically updating currency exchange rates.
 
-    See the documentation for django-money: https://github.com/django-money/django-money
+    Uses the exchangerate.host service API 
-
-    Specifically: https://github.com/django-money/django-money/tree/master/djmoney/contrib/exchange/backends
     """
 
-    name = 'inventree'
+    name = "InvenTreeExchange"
-    url = None
-    custom_rates = True
-    base_currency = None
-    currencies = []
-
-    def update_default_currency(self):
-        """ Update to base currency """
-
-        self.base_currency = InvenTreeSetting.get_setting('INVENTREE_DEFAULT_CURRENCY', 'USD')
-
-    def __init__(self, url=None):
-        """ Overrides init to update url, base currency and currencies """
-
-        self.url = url
-
-        self.update_default_currency()
-
-        # Update name
-        self.name = self.name + '-' + self.base_currency.lower()
-
-        self.currencies = inventree_settings.CURRENCIES
-
-        super().__init__()
-
-    def get_rates(self, **kwargs):
-        """ Returns a mapping <currency>: <rate> """
-
-        return kwargs.get('rates', {})
-
-    def get_stored_rates(self):
-        """ Returns stored rate for specified backend and base currency """
-
-        stored_rates = {}
-
-        stored_rates_obj = Rate.objects.all().prefetch_related('backend')
-
-        for rate in stored_rates_obj:
-            # Find match for backend and base currency
-            if rate.backend.name == self.name and rate.backend.base_currency == self.base_currency:
-                # print(f'{rate.currency} | {rate.value} | {rate.backend} | {rate.backend.base_currency}')
-                stored_rates[rate.currency] = rate.value
-
-        return stored_rates
-
-
-class ExchangeRateHostBackend(InvenTreeManualExchangeBackend):
-    """
-    Backend for https://exchangerate.host/
-    """
-
-    name = "exchangerate.host"
 
     def __init__(self):
         self.url = "https://api.exchangerate.host/latest"
 
-        self.custom_rates = False
+        super().__init__()
-
-        super().__init__(url=self.url)
 
     def get_params(self):
         # No API key is required
-        return {}
+        return {
+        }
 
-    def update_rates(self, base_currency=None):
+    def update_rates(self, base_currency=inventree_settings.BASE_CURRENCY):
-        """ Override update_rates method using currencies found in the settings
-        """
 
-        if base_currency:
+        symbols = ','.join(inventree_settings.CURRENCIES)
-            self.base_currency = base_currency
-        else:
-            self.update_default_currency()
-        
-        symbols = ','.join(self.currencies)
 
-        super().update_rates(base_currency=self.base_currency, symbols=symbols)
+        super().update_rates(base=base_currency, symbols=symbols)
-
-    def get_rates(self, **params):
-        """ Returns a mapping <currency>: <rate> """
-
-        # Set base currency
-        params.update(base=self.base_currency)
-
-        response = self.get_response(**params)
-
-        try:
-            return self.parse_json(response)['rates']
-        except KeyError:
-            # API response did not contain any rate
-            pass
-
-        return {}

InvenTree/InvenTree/settings.py

@@ -19,6 +19,8 @@ import shutil
 import sys
 from datetime import datetime
 
+import moneyed
+
 import yaml
 from django.utils.translation import gettext_lazy as _
 
@@ -513,11 +515,20 @@ CURRENCIES = CONFIG.get(
     ],
 )
 
-DEFAULT_CURRENCY = get_setting(
+# Check that each provided currency is supported
-    'INVENTREE_DEFAULT_CURRENCY',
+for currency in CURRENCIES:
-    CONFIG.get('default_currency', 'USD')
+    if currency not in moneyed.CURRENCIES:
+        print(f"Currency code '{currency}' is not supported")
+        sys.exit(1)
+
+BASE_CURRENCY = get_setting(
+    'INVENTREE_BASE_CURRENCY',
+    CONFIG.get('base_currency', 'USD')
 )
 
+# Custom currency exchange backend
+EXCHANGE_BACKEND = 'InvenTree.exchange.InvenTreeExchange'
+
 # Extract email settings from the config file
 email_config = CONFIG.get('email', {})
 

InvenTree/InvenTree/tasks.py

@@ -167,16 +167,16 @@ def update_exchange_rates():
     """
 
     try:
-        import common.models
+        from InvenTree.exchange import InvenTreeExchange
-        from InvenTree.exchange import ExchangeRateHostBackend
+        from django.conf import settings
     except AppRegistryNotReady:
         # Apps not yet loaded!
         return
 
-    backend = ExchangeRateHostBackend()
+    backend = InvenTreeExchange()
     print(f"Updating exchange rates from {backend.url}")
 
-    base = common.models.InvenTreeSetting.get_setting('INVENTREE_DEFAULT_CURRENCY')
+    base = settings.BASE_CURRENCY
 
     print(f"Using base currency '{base}'")
 

InvenTree/InvenTree/urls.py

@@ -41,7 +41,6 @@ from .views import IndexView, SearchView, DatabaseStatsView
 from .views import SettingsView, EditUserView, SetPasswordView
 from .views import AppearanceSelectView, SettingCategorySelectView
 from .views import DynamicJsView
-from .views import CurrencySettingsView
 
 from common.views import SettingEdit
 
@@ -91,7 +90,7 @@ settings_urls = [
     url(r'^build/?', SettingsView.as_view(template_name='InvenTree/settings/build.html'), name='settings-build'),
     url(r'^purchase-order/?', SettingsView.as_view(template_name='InvenTree/settings/po.html'), name='settings-po'),
     url(r'^sales-order/?', SettingsView.as_view(template_name='InvenTree/settings/so.html'), name='settings-so'),
-    url(r'^currencies/?', CurrencySettingsView.as_view(), name='settings-currencies'),
+    url(r'^currencies/?', SettingsView.as_view(template_name='InvenTree/settings/currencies.html'), name='settings-currencies'),
 
     url(r'^(?P<pk>\d+)/edit/', SettingEdit.as_view(), name='setting-edit'),
 

InvenTree/common/forms.py

@@ -13,6 +13,8 @@ from djmoney.forms.fields import MoneyField
 from InvenTree.forms import HelperForm
 from InvenTree.helpers import clean_decimal
 
+from common.settings import currency_code_default
+
 from .files import FileManager
 from .models import InvenTreeSetting
 
@@ -182,7 +184,7 @@ class MatchItem(forms.Form):
                         if 'price' in col_guess.lower():
                             self.fields[field_name] = MoneyField(
                                 label=_(col_guess),
-                                default_currency=InvenTreeSetting.get_setting('INVENTREE_DEFAULT_CURRENCY'),
+                                default_currency=currency_code_default(),
                                 decimal_places=5,
                                 max_digits=19,
                                 required=False,

InvenTree/common/models.py

@@ -19,6 +19,8 @@ from djmoney.models.fields import MoneyField
 from djmoney.contrib.exchange.models import convert_money
 from djmoney.contrib.exchange.exceptions import MissingRate
 
+from common.settings import currency_code_default
+
 from django.utils.translation import ugettext_lazy as _
 from django.core.validators import MinValueValidator, URLValidator
 from django.core.exceptions import ValidationError
@@ -80,20 +82,6 @@ class InvenTreeSetting(models.Model):
             'default': '',
         },
 
-        'INVENTREE_DEFAULT_CURRENCY': {
-            'name': _('Default Currency'),
-            'description': _('Default currency'),
-            'default': 'USD',
-            'choices': djmoney.settings.CURRENCY_CHOICES,
-        },
-
-        'CUSTOM_EXCHANGE_RATES': {
-            'name': _('Custom Exchange Rates'),
-            'description': _('Enable custom exchange rates'),
-            'validator': bool,
-            'default': False,
-        },
-
         'INVENTREE_DOWNLOAD_FROM_URL': {
             'name': _('Download from URL'),
             'description': _('Allow download of remote images and files from external URL'),
@@ -766,7 +754,7 @@ def get_price(instance, quantity, moq=True, multiples=True, currency=None):
 
     if currency is None:
         # Default currency selection
-        currency = InvenTreeSetting.get_setting('INVENTREE_DEFAULT_CURRENCY')
+        currency = currency_code_default()
 
     pb_min = None
     for pb in instance.price_breaks.all():

InvenTree/common/settings.py

@@ -7,7 +7,8 @@ from __future__ import unicode_literals
 
 from moneyed import CURRENCIES
 
-from common.models import InvenTreeSetting
+import common.models
+from django.conf import settings
 
 
 def currency_code_default():
@@ -15,7 +16,7 @@ def currency_code_default():
     Returns the default currency code (or USD if not specified)
     """
 
-    code = InvenTreeSetting.get_setting('INVENTREE_DEFAULT_CURRENCY')
+    code = settings.BASE_CURRENCY
 
     if code not in CURRENCIES:
         code = 'USD'
@@ -28,4 +29,4 @@ def stock_expiry_enabled():
     Returns True if the stock expiry feature is enabled
     """
 
-    return InvenTreeSetting.get_setting('STOCK_ENABLE_EXPIRY')
+    return common.models.InvenTreeSetting.get_setting('STOCK_ENABLE_EXPIRY')

InvenTree/config_template.yaml

@@ -52,6 +52,9 @@ language: en-us
 # Use the environment variable INVENTREE_TIMEZONE
 timezone: UTC
 
+# Base currency code
+base_currency: USD
+
 # List of currencies supported by default.
 # Add other currencies here to allow use in InvenTree
 currencies:

InvenTree/part/views.py

@@ -2675,7 +2675,7 @@ class PartSalePriceBreakCreate(AjaxCreateView):
 
         initials['part'] = self.get_part()
 
-        default_currency = InvenTreeSetting.get_setting('INVENTREE_DEFAULT_CURRENCY')
+        default_currency = settings.BASE_CURRENCY
         currency = CURRENCIES.get(default_currency, None)
 
         if currency is not None:

InvenTree/templates/InvenTree/settings/tabs.html

@@ -15,6 +15,9 @@
     <li {% if tab == 'global' %} class='active' {% endif %}>
         <a href='{% url "settings-global" %}'><span class='fas fa-globe'></span> {% trans "Global" %}</a>
     </li>
+    <li {% if tab == 'currencies' %} class='active'{% endif %}>
+        <a href="{% url 'settings-currencies' %}"><span class='fas fa-dollar-sign'></span> {% trans "Currencies" %}</a>
+    </li>
     <li {% if tab == 'report' %} class='active' {% endif %}>
         <a href='{% url "settings-report" %}'><span class='fas fa-file-pdf'></span> {% trans "Report" %}</a>
     </li>
@@ -36,8 +39,5 @@
     <li {% if tab == 'so' %} class='active'{% endif %}>
         <a href="{% url 'settings-so' %}"><span class='fas fa-truck'></span> {% trans "Sales Orders" %}</a>
     </li>
-    <li {% if tab == 'currencies' %} class='active'{% endif %}>
-        <a href="{% url 'settings-currencies' %}"><span class='fas fa-dollar-sign'></span> {% trans "Currencies" %}</a>
-    </li>
 </ul>
 {% endif %}