Handle both in-memory and local file objects

todo/management/commands/import_csv.py

@@ -1,5 +1,6 @@
 import sys
 from typing import Any
+from pathlib import Path
 
 from django.core.management.base import BaseCommand, CommandParser
 
@@ -24,11 +25,15 @@ class Command(BaseCommand):
             print("Sorry, we need a file name to work from.")
             sys.exit(1)
         else:
-            # Don't check validity of filepath here; upserter will do that.
             filepath = str(options.get("file"))
+            if not Path(filepath).exists():
+                print(f"Sorry, couldn't find file: {filepath}")
+                sys.exit(1)
 
+        with open(filepath, mode="r", encoding="utf-8-sig") as fileobj:
+            # Pass in a file *object*, not a path
             importer = CSVImporter()
-        results = importer.upsert(filepath)
+            results = importer.upsert(fileobj, as_string_obj=True)
 
         # Report successes, failures and summaries
         print()

todo/operations/csv_importer.py

@@ -1,8 +1,7 @@
+import codecs
 import csv
 import datetime
 import logging
-import sys
-from pathlib import Path
 
 from django.contrib.auth import get_user_model
 from django.contrib.auth.models import Group
@@ -24,18 +23,22 @@ class CSVImporter:
         self.line_count = 0
         self.upsert_count = 0
 
-    def upsert(self, filepath):
+    def upsert(self, fileobj, as_string_obj=False):
+        """Expects a file *object*, not a file path. This is important because this has to work for both
+        the management command and the web uploader; the web uploader will pass in in-memory file
+        with no path!
 
-        if not Path(filepath).exists():
-            print(f"Sorry, couldn't find file: {filepath}")
-            sys.exit(1)
+        Header row is:
+        Title, Group, Task List, Created Date, Due Date, Completed, Created By, Assigned To, Note, Priority
+        """
 
-        with open(filepath, mode="r", encoding="utf-8-sig") as csv_file:
-            # Have arg and good file path -- read in rows as dicts.
-            # Header row is:
-            # Title, Group, Task List, Created Date, Due Date, Completed, Created By, Assigned To, Note, Priority
+        if as_string_obj:
+            # fileobj comes from mgmt command
+            csv_reader = csv.DictReader(fileobj)
+        else:
+            # fileobj comes from browser upload (in-memory)
+            csv_reader = csv.DictReader(codecs.iterdecode(fileobj, "utf-8"))
 
-            csv_reader = csv.DictReader(csv_file)
         for row in csv_reader:
             self.line_count += 1