Create new file bom.py for BOM helper functions

- New class for managing BOM upload

InvenTree/InvenTree/helpers.py

@@ -92,33 +92,6 @@ def MakeBarcode(object_type, object_id, object_url, data={}):
     return json.dumps(data, sort_keys=True)
 
 
-def IsValidSpreadsheetFormat(fmt):
-    """ Test if a file format specifier is in the valid list of spreadsheet file formats """
-
-    return fmt.lower() in ['csv', 'xls', 'xlsx', 'tsv']
-
-
-def MakeBomTemplate(fmt):
-    """ Generate a Bill of Materials upload template file (for user download) """
-
-    if not IsValidSpreadsheetFormat(fmt):
-        fmt = 'csv'
-
-    fields = [
-        'Part',
-        'Quantity',
-        'Overage',
-        'Reference',
-        'Notes'
-    ]
-
-    data = tablib.Dataset(headers=fields).export(fmt)
-
-    filename = 'InvenTree_BOM_Template.' + fmt
-
-    return DownloadFile(data, filename)
-
-
 def DownloadFile(data, filename, content_type='application/text'):
     """ Create a dynamic file for the user to download.
     

InvenTree/part/bom.py

@@ -0,0 +1,92 @@
+"""
+Functionality for Bill of Material (BOM) management.
+Primarily BOM upload tools.
+"""
+
+from fuzzywuzzy import fuzz
+import tablib
+import os
+
+from django.utils.translation import gettext_lazy as _
+from django.core.exceptions import ValidationError
+from .models import Part, BomItem
+
+from InvenTree.helpers import DownloadFile
+
+
+def IsValidBOMFormat(fmt):
+    """ Test if a file format specifier is in the valid list of BOM file formats """
+
+    return fmt.strip().lower() in ['csv', 'xls', 'xlsx', 'tsv']
+
+
+def MakeBomTemplate(fmt):
+    """ Generate a Bill of Materials upload template file (for user download) """
+
+    fmt = fmt.strip().lower()
+
+    if not IsValidBOMFormat(fmt):
+        fmt = 'csv'
+
+    fields = [
+        'Part',
+        'Quantity',
+        'Overage',
+        'Reference',
+        'Notes'
+    ]
+
+    data = tablib.Dataset(headers=fields).export(fmt)
+
+    filename = 'InvenTree_BOM_Template.' + fmt
+
+    return DownloadFile(data, filename)
+
+
+class BomUploadManager:
+    """ Class for managing an uploaded BOM file """
+
+    # Fields which are absolutely necessary for valid upload
+    REQUIRED_HEADERS = [
+        'Part',
+        'Quantity',
+    ]
+
+    # Fields which are not necessary but can be populated
+    USEFUL_HEADERS = [
+        'REFERENCE',
+        'OVERAGE',
+        'NOTES'
+    ]
+
+    def __init__(self, bom_file, starting_row=2):
+        """ Initialize the BomUpload class with a user-uploaded file object """
+        self.starting_row = starting_row
+        print("Starting on row", starting_row)
+        self.process(bom_file)
+
+    def process(self, bom_file):
+        """ Process a BOM file """
+
+        ext = os.path.splitext(bom_file.name)[-1].lower()
+
+        if ext in ['.csv', '.tsv', ]:
+            # These file formats need string decoding
+            raw_data = bom_file.read().decode('utf-8')
+        elif ext in ['.xls', '.xlsx']:
+            raw_data = bom_file.read()
+        else:
+            raise ValidationError({'bom_file': _('Unsupported file format: {f}'.format(f=ext))})
+
+        try:
+            bom_data = tablib.Dataset().load(raw_data)
+        except tablib.UnsupportedFormat:
+            raise ValidationError({'bom_file': _('Error reading BOM file (invalid data)')})
+
+        # Now we have BOM data in memory!
+
+        headers = [h.lower() for h in bom_data.headers]
+
+        for header in self.REQUIRED_HEADERS:
+            if not header.lower() in headers:
+                raise ValidationError({'bom_file': _("Missing required field '{f}'".format(f=header))})

InvenTree/part/views.py

@@ -8,6 +8,7 @@ from __future__ import unicode_literals
 import tablib
 import os
 
+from django.core.exceptions import ValidationError
 from django.shortcuts import get_object_or_404
 from django.utils.translation import gettext_lazy as _
 from django.urls import reverse_lazy
@@ -23,11 +24,12 @@ from .models import match_part_names
 from company.models import SupplierPart
 
 from . import forms as part_forms
+from .bom import  MakeBomTemplate, BomUploadManager
 
 from InvenTree.views import AjaxView, AjaxCreateView, AjaxUpdateView, AjaxDeleteView
 from InvenTree.views import QRCodeView
 
-from InvenTree.helpers import DownloadFile, str2bool, MakeBomTemplate
+from InvenTree.helpers import DownloadFile, str2bool
 from InvenTree.status_codes import OrderStatus
 
 
@@ -679,35 +681,15 @@ class BomUpload(AjaxView, FormMixin):
             'form_valid': False
         }
 
-        # Extract the file format data
-        ext = os.path.splitext(bom_file.name)[-1].lower()
-
-        if ext in ['.csv', '.tsv', ]:
-            # These file formats need string decoding
-            raw_data = bom_file.read().decode('utf-8')
-        elif ext in ['.xls', '.xlsx']:
-            raw_data = bom_file.read()
-        else:
-            self.form.errors['bom_file'] = ['Unsupported file format: ' + ext]
-            return self.renderJsonResponse(self.request, self.form, data)
-
-        # Now try to read the data
+        # Create a BomUploadManager object - will perform initial data validation
+        # (and raise a ValidationError if there is something wrong with the file)
         try:
-            bom_data = tablib.Dataset().load(raw_data)
+            manager = BomUploadManager(bom_file, self.form['starting_row'].value())
+        except ValidationError as e:
+            errors = e.error_dict
 
-            headers = [h.lower() for h in bom_data.headers]
-
-            # Minimal set of required fields
-            for header in ['part', 'quantity', 'reference']:
-                if not header in headers:
-                    self.form.errors['bom_file'] = [_("Missing required field '{f}'".format(f=header))]
-                    break
-
-        except tablib.UnsupportedFormat:
-            valid = False
-            self.form.errors['bom_file'] = [
-                "Error reading '{f}' (Unsupported file format)".format(f=str(bom_file)),
-            ]
+            for k,v in errors.items():
+                self.form.errors[k] = v
 
         return self.renderJsonResponse(self.request, self.form, data=data)