A-6 完了。 本セッションの進捗まとめ:

タスク	内容	状態
A-3	前年度コピーボタン	✅ 完了
A-4	品種のインライン追加・削除	✅ 完了
A-5	PDFプレビュー機能	✅ 完了
A-6	エクスポート機能	✅ 完了
残りタスク:

A-2: チェックボックス・一括操作
A-1: ダッシュボード画面
A-7: 検索・フィルタ
確認ポイント:

作付け計画 (/allocation): 年度セレクタの横に「前年度コピー」「品種管理」ボタン、品種セレクトに「+ 新しい品種を追加...」
帳票出力 (/reports): 各帳票にプレビュー/ダウンロードの2ボタン
データ取込 (/import): ページ下部に「データエクスポート」(ZIPダウンロード)

backend/apps/fields/urls.py

@@ -9,6 +9,7 @@ urlpatterns = [
     path('import/kyosai/', views.import_kyosai_master, name='import_kyosai'),
     path('import/yoshida/', views.import_yoshida_fields, name='import_yoshida'),
     path('import/chusankan/', views.import_chusankan_master, name='import_chusankan'),
+    path('export/zip/', views.export_all_zip, name='export_all_zip'),
     path('<int:field_id>/kyosai-links/', views.add_kyosai_links, name='add_kyosai_links'),
     path('<int:field_id>/kyosai-links/<int:kyosai_id>/', views.remove_kyosai_link, name='remove_kyosai_link'),
     path('<int:field_id>/chusankan-links/', views.add_chusankan_links, name='add_chusankan_links'),

backend/apps/fields/views.py

@@ -1,6 +1,10 @@
+import csv
+import io
+import json
+import zipfile
 import pandas as pd
 from django.db import models as django_models
-from django.http import JsonResponse
+from django.http import JsonResponse, HttpResponse
 from django.shortcuts import get_object_or_404
 from django.views.decorators.csrf import csrf_exempt
 from django.views.decorators.http import require_http_methods
@@ -298,3 +302,79 @@ def import_chusankan_master(request):
 
     except Exception as e:
         return JsonResponse({'error': str(e)}, status=500)
+
+
+@api_view(['GET'])
+@perm_classes([permissions.IsAuthenticated])
+def export_all_zip(request):
+    """全データをCSV形式でZIPアーカイブとしてエクスポート"""
+    from apps.plans.models import Plan, Crop, Variety
+
+    buf = io.BytesIO()
+    with zipfile.ZipFile(buf, 'w', zipfile.ZIP_DEFLATED) as zf:
+        # 1. Fields CSV
+        fields_csv = io.StringIO()
+        w = csv.writer(fields_csv)
+        w.writerow(['id', 'name', 'address', 'area_tan', 'area_m2', 'owner_name', 'group_name', 'display_order'])
+        for f in Field.objects.all().order_by('id'):
+            w.writerow([f.id, f.name, f.address, f.area_tan, f.area_m2, f.owner_name, f.group_name or '', f.display_order or 0])
+        zf.writestr('fields.csv', fields_csv.getvalue())
+
+        # 2. Kyosai CSV
+        kyosai_csv = io.StringIO()
+        w = csv.writer(kyosai_csv)
+        w.writerow(['id', 'k_num', 's_num', 'address', 'kanji_name', 'area'])
+        for k in OfficialKyosaiField.objects.all().order_by('id'):
+            w.writerow([k.id, k.k_num, k.s_num, k.address, k.kanji_name, k.area])
+        zf.writestr('kyosai_fields.csv', kyosai_csv.getvalue())
+
+        # 3. Chusankan CSV
+        chusankan_csv = io.StringIO()
+        w = csv.writer(chusankan_csv)
+        w.writerow(['id', 'c_id', 'chusankan_flag', 'oaza', 'aza', 'chiban', 'branch_num',
+                     'land_type', 'area', 'planting_area', 'original_crop', 'manager', 'owner',
+                     'slope', 'base_amount', 'steep_slope_addition', 'smart_agri_addition', 'payment_amount'])
+        for c in OfficialChusankanField.objects.all().order_by('id'):
+            w.writerow([c.id, c.c_id, c.chusankan_flag or '', c.oaza, c.aza, c.chiban,
+                         c.branch_num or '', c.land_type or '', c.area, c.planting_area or '',
+                         c.original_crop or '', c.manager or '', c.owner or '', c.slope or '',
+                         c.base_amount or '', c.steep_slope_addition or '', c.smart_agri_addition or '',
+                         c.payment_amount or ''])
+        zf.writestr('chusankan_fields.csv', chusankan_csv.getvalue())
+
+        # 4. Plans CSV
+        plans_csv = io.StringIO()
+        w = csv.writer(plans_csv)
+        w.writerow(['id', 'field_id', 'field_name', 'year', 'crop_id', 'crop_name', 'variety_id', 'variety_name', 'notes'])
+        for p in Plan.objects.select_related('field', 'crop', 'variety').all().order_by('year', 'field_id'):
+            w.writerow([p.id, p.field_id, p.field.name, p.year, p.crop_id, p.crop.name,
+                         p.variety_id or '', p.variety.name if p.variety else '', p.notes or ''])
+        zf.writestr('plans.csv', plans_csv.getvalue())
+
+        # 5. Crops & Varieties CSV
+        crops_csv = io.StringIO()
+        w = csv.writer(crops_csv)
+        w.writerow(['crop_id', 'crop_name', 'variety_id', 'variety_name'])
+        for crop in Crop.objects.prefetch_related('varieties').all().order_by('id'):
+            if crop.varieties.count() == 0:
+                w.writerow([crop.id, crop.name, '', ''])
+            else:
+                for v in crop.varieties.all().order_by('id'):
+                    w.writerow([crop.id, crop.name, v.id, v.name])
+        zf.writestr('crops_varieties.csv', crops_csv.getvalue())
+
+        # 6. M:N links (field_kyosai, field_chusankan)
+        links_csv = io.StringIO()
+        w = csv.writer(links_csv)
+        w.writerow(['field_id', 'field_name', 'link_type', 'linked_id'])
+        for f in Field.objects.prefetch_related('kyosai_fields', 'chusankan_fields').all().order_by('id'):
+            for k in f.kyosai_fields.all():
+                w.writerow([f.id, f.name, 'kyosai', k.id])
+            for c in f.chusankan_fields.all():
+                w.writerow([f.id, f.name, 'chusankan', c.id])
+        zf.writestr('field_links.csv', links_csv.getvalue())
+
+    buf.seek(0)
+    response = HttpResponse(buf.read(), content_type='application/zip')
+    response['Content-Disposition'] = 'attachment; filename="keinasystem_backup.zip"'
+    return response