Add basic ability to download Ordering Batch as Excel spreadsheet

setup.py

@@ -83,6 +83,7 @@ requires = [
 
     'humanize',                         # 0.5.1
     'Mako',                             # 0.6.2
+    'openpyxl',                         # 2.4.7
     'pyramid_beaker>=0.6',              #                       0.6.1
     'pyramid_debugtoolbar',             # 1.0
     'pyramid_exclog',                   # 0.6

tailbone/templates/ordering/view.mako

@@ -27,6 +27,13 @@
   ${h.stylesheet_link(request.static_url('tailbone:static/css/purchases.css'))}
 </%def>
 
+<%def name="context_menu_items()">
+  ${parent.context_menu_items()}
+  % if request.has_perm('{}.download_excel'.format(permission_prefix)):
+      <li>${h.link_to("Download {} as Excel".format(model_title), url('{}.download_excel'.format(route_prefix), uuid=batch.uuid))}</li>
+  % endif
+</%def>
+
 <%def name="leading_buttons()">
   % if not batch.complete and not batch.executed and request.has_perm('ordering.order_form'):
       <button type="button" id="order-form">Ordering Form</button>

tailbone/views/purchasing/ordering.py

@@ -26,12 +26,18 @@ Views for 'ordering' (purchasing) batches
 
 from __future__ import unicode_literals, absolute_import
 
+import os
+
+import six
+import openpyxl
 from sqlalchemy import orm
 
 from rattail.db import model, api
 from rattail.core import Object
 from rattail.time import localtime
 
+from pyramid.response import FileResponse
+
 from tailbone import forms
 from tailbone.views.purchasing import PurchasingBatchView
 
@@ -218,6 +224,37 @@ class OrderingBatchView(PurchasingBatchView):
             'batch_po_total': '${:0,.2f}'.format(batch.po_total or 0),
         }
 
+    def download_excel(self):
+        """
+        Download ordering batch as Excel spreadsheet.
+        """
+        batch = self.get_instance()
+
+        # populate Excel worksheet
+        workbook = openpyxl.Workbook()
+        worksheet = workbook.active
+        worksheet.title = "Purchase Order"
+        worksheet.append(["Store", "Vendor", "Date ordered"])
+        worksheet.append([batch.store.name, batch.vendor.name, batch.date_ordered.strftime('%m/%d/%Y')])
+        worksheet.append([])
+        worksheet.append(['vendor_code', 'upc', 'brand_name', 'description', 'case_quantity', 'cases_ordered', 'units_ordered'])
+        for row in batch.active_rows():
+            worksheet.append([row.vendor_code, six.text_type(row.upc), row.brand_name,
+                              '{} {}'.format(row.description, row.size),
+                              row.case_quantity, row.cases_ordered, row.units_ordered])
+
+        # write Excel file to batch data dir
+        filedir = batch.filedir(self.rattail_config)
+        if not os.path.exists(filedir):
+            os.makedirs(filedir)
+        filename = 'PO.{}.xlsx'.format(batch.id_str)
+        path = batch.filepath(self.rattail_config, filename)
+        workbook.save(path)
+
+        response = FileResponse(path, request=self.request)
+        response.content_length = os.path.getsize(path)
+        response.content_disposition = b'attachment; filename="{}"'.format(filename)
+        return response
 
     @classmethod
     def defaults(cls, config):
@@ -242,6 +279,13 @@ class OrderingBatchView(PurchasingBatchView):
         config.add_view(cls, attr='order_form_update', route_name='{}.order_form_update'.format(route_prefix),
                         renderer='json', permission='{}.order_form'.format(permission_prefix))
 
+        # download as Excel
+        config.add_route('{}.download_excel'.format(route_prefix), '{}/{{uuid}}/excel'.format(url_prefix))
+        config.add_view(cls, attr='download_excel', route_name='{}.download_excel'.format(route_prefix),
+                        permission='{}.download_excel'.format(permission_prefix))
+        config.add_tailbone_permission(permission_prefix, '{}.download_excel'.format(permission_prefix),
+                                       "Download {} as Excel".format(model_title))
+
 
 def includeme(config):
     OrderingBatchView.defaults(config)