Add get_product_key_field() and _label() to AppHandler

and deprecate corresponding config methods

rattail/app.py

@@ -42,7 +42,7 @@ import humanize
 from mako.template import Template
 
 from rattail.util import (load_object, load_entry_points,
-                          progress_loop,
+                          progress_loop, prettify,
                           pretty_quantity, pretty_hours,
                           NOTSET)
 from rattail.files import temp_path, resource_path
@@ -1200,6 +1200,32 @@ class AppHandler(object):
         """
         return self.get_membership_handler().get_member(obj, **kwargs)
 
+    def get_product_key_field(self):
+        """
+        Returns the configured fieldname for product key,
+        e.g. ``'upc'``.
+        """
+        return self.config.get('rattail', 'product.key', default='upc')
+
+    def get_product_key_label(self, field=None):
+        """
+        Returns the configured field label for product key,
+        e.g. ``'UPC'``.
+        """
+        title = self.config.get('rattail', 'product.key_title')
+        if title:
+            return title
+
+        if not field:
+            field = self.get_product_key_field()
+
+        if field == 'upc':
+            return "UPC"
+        if field == 'item_id':
+            return "Item ID"
+
+        return prettify(field)
+
     def get_session(self, obj):
         """
         Returns the SQLAlchemy session with which the given object is

rattail/config.py

@@ -41,7 +41,6 @@ from rattail.util import load_entry_points, load_object
 from rattail.exceptions import WindowsExtensionsNotInstalled, ConfigurationError
 from rattail.files import temp_path
 from rattail.logging import TimeConverter
-from rattail.util import prettify
 
 
 log = logging.getLogger(__name__)
@@ -643,33 +642,25 @@ class RattailConfiguration:
         return self.get_bool('rattail.db.versioning.enabled', usedb=False,
                              default=False)
 
-    def product_key(self, default='upc'):
+    def product_key(self, **kwargs):
         """
-        Returns the name of the attribute which should be treated as
+        Deprecated; instead please see
-        the canonical product key field, e.g. ``'upc'`` or
+        :meth:`rattail.app.AppHandler.get_product_key_field()`.
-        ``'item_id'`` etc.
         """
-        return self.get('rattail.product.key', default=default)
+        warnings.warn("config.product_key() is deprecated; please "
+                      "use app.get_product_key_field() instead",
+                      DeprecationWarning, stacklevel=2)
+        return self.get_app().get_product_key_field()
 
     def product_key_title(self, key=None):
         """
-        Returns the title string to be used when displaying product
+        Deprecated; instead please see
-        key field, e.g. "UPC" or "Part No." etc.
+        :meth:`rattail.app.AppHandler.get_product_key_label()`.
-
-        :param key: The product key for which to return a label.  This
-           is optional; if not specified then :meth:`product_key()`
-           will be called to determine the key.
         """
-        title = self.get('rattail.product.key_title')
+        warnings.warn("config.product_key_title() is deprecated; please "
-        if title:
+                      "use app.get_product_key_label() instead",
-            return title
+                      DeprecationWarning, stacklevel=2)
-        if not key:
+        return self.get_app().get_product_key_label(field=key)
-            key = self.product_key()
-        if key == 'upc':
-            return "UPC"
-        if key == 'item_id':
-            return "Item ID"
-        return prettify(key)
 
     def app_package(self, default=None):
         """
@@ -1474,32 +1465,25 @@ class RattailConfig(object):
         spec = self.require('rattail.trainwreck', 'model', usedb=False)
         return importlib.import_module(spec)
 
-    def product_key(self, default='upc'):
+    def product_key(self, **kwargs):
         """
-        Returns the name of the attribute which should be treated as the
+        Deprecated; instead please see
-        canonical product key field, e.g. 'upc' or 'item_id' etc.
+        :meth:`rattail.app.AppHandler.get_product_key_field()`.
         """
-        return self.get('rattail', 'product.key', default=default) or default
+        warnings.warn("config.product_key() is deprecated; please "
+                      "use app.get_product_key_field() instead",
+                      DeprecationWarning, stacklevel=2)
+        return self.get_app().get_product_key_field()
 
     def product_key_title(self, key=None):
         """
-        Returns the title string to be used when displaying product key field,
+        Deprecated; instead please see
-        e.g. "UPC" or "Part No." etc.
+        :meth:`rattail.app.AppHandler.get_product_key_label()`.
-
-        :param key: The product key for which to return a label.  This
-           is optional; if not specified then :meth:`product_key()`
-           will be called to determine the key.
         """
-        title = self.get('rattail', 'product.key_title')
+        warnings.warn("config.product_key_title() is deprecated; please "
-        if title:
+                      "use app.get_product_key_label() instead",
-            return title
+                      DeprecationWarning, stacklevel=2)
-        if not key:
+        return self.get_app().get_product_key_label(field=key)
-            key = self.product_key()
-        if key == 'upc':
-            return "UPC"
-        if key == 'item_id':
-            return "Item ID"
-        return prettify(key)
 
     def single_store(self):
         """