[WIP] Pricing plugin

docs/docs/settings/global.md

@@ -108,6 +108,7 @@ Configuration of pricing data and currency support:
 {{ globalsetting("CURRENCY_CODES") }}
 {{ globalsetting("CURRENCY_UPDATE_PLUGIN") }}
 {{ globalsetting("CURRENCY_UPDATE_INTERVAL") }}
+{{ globalsetting("PRICING_PLUGIN") }}
 {{ globalsetting("PRICING_DECIMAL_PLACES_MIN") }}
 {{ globalsetting("PRICING_DECIMAL_PLACES") }}
 {{ globalsetting("PRICING_AUTO_UPDATE") }}

src/backend/InvenTree/InvenTree/helpers.py

@@ -29,8 +29,6 @@
 from djmoney.money import Money
 from PIL import Image
 
-from common.currency import currency_code_default
-
 from .settings import MEDIA_URL, STATIC_URL
 
 logger = structlog.get_logger('inventree')
@@ -399,7 +397,7 @@ def decimal2string(d):
     return s.rstrip('0').rstrip('.')
 
 
-def decimal2money(d, currency=None):
+def decimal2money(d, currency: Optional[str] = None) -> Money:
     """Format a Decimal number as Money.
 
     Args:
@@ -409,12 +407,12 @@ def decimal2money(d, currency=None):
     Returns:
         A Money object from the input(s)
     """
-    if not currency:
-        currency = currency_code_default()
-    return Money(d, currency)
+    from common.currency import currency_code_default
+
+    return Money(d, currency or currency_code_default())
 
 
-def WrapWithQuotes(text, quote='"'):
+def WrapWithQuotes(text: str, quote: str = '"') -> str:
     """Wrap the supplied text with quotes.
 
     Args:
@@ -424,6 +422,8 @@ def WrapWithQuotes(text, quote='"'):
     Returns:
         Supplied text wrapped in quote char
     """
+    text = str(text)
+
     if not text.startswith(quote):
         text = quote + text
 

src/backend/InvenTree/common/currency.py

@@ -8,6 +8,9 @@
 from django.utils.translation import gettext_lazy as _
 
 import structlog
+from djmoney.contrib.exchange.exceptions import MissingRate
+from djmoney.contrib.exchange.models import convert_money
+from djmoney.money import Money
 from moneyed import CURRENCIES
 
 import InvenTree.helpers
@@ -131,19 +134,41 @@ def validate_currency_codes(value):
     return list(valid_currencies)
 
 
-def currency_exchange_plugins() -> Optional[list]:
-    """Return a list of plugin choices which can be used for currency exchange."""
-    try:
-        from plugin import PluginMixinEnum, registry
+def convert_currency(
+    money: Money, currency: Optional[str] = None, raise_error: bool = False
+) -> Money:
+    """Convert a Money object to the specified currency.
 
-        plugs = registry.with_mixin(PluginMixinEnum.CURRENCY_EXCHANGE, active=True)
-    except Exception:
-        plugs = []
+    Arguments:
+        money: The Money object to convert
+        currency: The target currency code (e.g. 'USD').
+        raise_error: If True, raise an exception if conversion fails.
 
-    if len(plugs) == 0:
+    If no currency is specified, convert to the default currency.
+    """
+    if money is None:
         return None
 
-    return [('', _('No plugin'))] + [(plug.slug, plug.human_name) for plug in plugs]
+    if currency is None:
+        currency = currency_code_default()
+
+    target_currency = currency_code_default()
+
+    try:
+        result = convert_money(money, target_currency)
+    except MissingRate as exc:
+        logger.warning(
+            'No currency conversion rate available for %s -> %s',
+            money.currency,
+            target_currency,
+        )
+
+        if raise_error:
+            raise exc
+
+        result = None
+
+        return result
 
 
 def get_price(

src/backend/InvenTree/common/pricing.py

@@ -0,0 +1,38 @@
+"""Helper functions for pricing support."""
+
+from dataclasses import dataclass
+
+from djmoney.money import Money
+
+from common.settings import get_global_setting
+from plugin import PluginMixinEnum, registry
+from plugin.models import InvenTreePlugin
+
+
+@dataclass
+class PriceRangeTuple:
+    """Dataclass representing a price range."""
+
+    min: Money
+    max: Money
+
+
+def get_pricing_plugin() -> InvenTreePlugin:
+    """Return the selected pricing plugin.
+
+    Attempts to retrieve the currently selected pricing plugin from the plugin registry.
+    If the plugin is not available, or is disabled,
+    then return the default InvenTreePricing plugin.
+    """
+    default_slug = 'inventree-pricing'
+
+    plugin_slug = get_global_setting('PRICING_PLUGIN', backup_value=default_slug)
+
+    plugin = registry.get_plugin(plugin_slug, with_mixin=PluginMixinEnum.PRICING)
+
+    if plugin is None:
+        plugin = registry.get_plugin(default_slug, with_mixin=PluginMixinEnum.PRICING)
+
+    # TODO: Handle case where default plugin is missing?
+
+    return plugin

src/backend/InvenTree/common/setting/system.py

@@ -4,6 +4,7 @@
 import os
 import re
 import uuid
+from typing import Optional
 
 from django.conf import settings as django_settings
 from django.contrib.auth.models import Group
@@ -15,7 +16,6 @@
 
 import build.validators
 import common.currency
-import common.models
 import common.validators
 import order.validators
 import report.helpers
@@ -107,18 +107,28 @@ def reload_plugin_registry(setting):
     registry.reload_plugins(full_reload=True, force_reload=True, collect=True)
 
 
-def barcode_plugins() -> list:
+def currency_exchange_plugins() -> Optional[list]:
+    """Return a list of plugin choices which can be used for currency exchange."""
+    from plugin import PluginMixinEnum
+    from plugin.registry import get_plugin_options
+
+    return get_plugin_options(PluginMixinEnum.CURRENCY_EXCHANGE, allow_null=True)
+
+
+def barcode_plugins() -> Optional[list]:
     """Return a list of plugin choices which can be used for barcode generation."""
-    try:
-        from plugin import PluginMixinEnum, registry
+    from plugin import PluginMixinEnum
+    from plugin.registry import get_plugin_options
 
-        plugins = registry.with_mixin(PluginMixinEnum.BARCODE, active=True)
-    except Exception:  # pragma: no cover
-        plugins = []
+    return get_plugin_options(PluginMixinEnum.BARCODE, allow_null=False)
 
-    return [
-        (plug.slug, plug.human_name) for plug in plugins if plug.has_barcode_generation
-    ]
+
+def pricing_plugins() -> Optional[list]:
+    """Return a list of plugin choices which can be used for pricing calculations."""
+    from plugin import PluginMixinEnum
+    from plugin.registry import get_plugin_options
+
+    return get_plugin_options(PluginMixinEnum.PRICING, allow_null=False)
 
 
 def default_uuid4() -> str:
@@ -257,7 +267,7 @@ class SystemSetId:
     'CURRENCY_UPDATE_PLUGIN': {
         'name': _('Currency Update Plugin'),
         'description': _('Currency update plugin to use'),
-        'choices': common.currency.currency_exchange_plugins,
+        'choices': currency_exchange_plugins,
         'default': 'inventreecurrencyexchange',
     },
     'INVENTREE_DOWNLOAD_FROM_URL': {
@@ -530,6 +540,12 @@ class SystemSetId:
         'default': True,
         'validator': bool,
     },
+    'PRICING_PLUGIN': {
+        'name': _('Pricing Plugin'),
+        'description': _('Plugin to use for pricing calculations'),
+        'choices': pricing_plugins,
+        'default': 'inventree-pricing',
+    },
     'PRICING_DECIMAL_PLACES_MIN': {
         'name': _('Minimum Pricing Decimal Places'),
         'description': _(