Day 3 のデータモデル実装が完了しました。

完了内容
models.py
fields/models.py:
- OfficialKyosaiField - 共済マスタ
- OfficialChusankanField - 中山間マスタ
- Field - 圃場（PointField で位置情報対応）
plans/models.py:
- Crop - 作物マスタ
- Variety - 品種マスタ（unique_together 制約）
- Plan - 作付け計画（unique_together 制約）
admin.py
- 全てのモデルを admin に登録
- list_display, search_fields, list_filter 設定
- FieldAdmin は GIS 用 GISModelAdmin を使用
マイグレーション
✅ makemigrations - 成功
✅ migrate - 成功
管理画面 (http://localhost:8000/admin) で全てのモデルが確認・編集できます。

backend/apps/plans/admin.py

@@ -1,3 +1,23 @@
 from django.contrib import admin
+from .models import Crop, Variety, Plan
 
-# Register your models here.
+
+@admin.register(Crop)
+class CropAdmin(admin.ModelAdmin):
+    list_display = ('name',)
+    search_fields = ('name',)
+
+
+@admin.register(Variety)
+class VarietyAdmin(admin.ModelAdmin):
+    list_display = ('crop', 'name')
+    search_fields = ('name', 'crop__name')
+    list_filter = ('crop',)
+
+
+@admin.register(Plan)
+class PlanAdmin(admin.ModelAdmin):
+    list_display = ('field', 'year', 'crop', 'variety', 'notes')
+    search_fields = ('field__name', 'crop__name', 'variety__name')
+    list_filter = ('year', 'crop')
+    ordering = ('-year', 'field')

backend/apps/plans/migrations/0001_initial.py

@@ -0,0 +1,57 @@
+# Generated by Django 5.0 on 2026-02-15 02:45
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    initial = True
+
+    dependencies = [
+        ('fields', '0001_initial'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='Crop',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('name', models.CharField(max_length=100, unique=True, verbose_name='作物名')),
+            ],
+            options={
+                'verbose_name': '作物マスタ',
+                'verbose_name_plural': '作物マスタ',
+            },
+        ),
+        migrations.CreateModel(
+            name='Variety',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('name', models.CharField(max_length=100, verbose_name='品種名')),
+                ('crop', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='varieties', to='plans.crop', verbose_name='作物')),
+            ],
+            options={
+                'verbose_name': '品種マスタ',
+                'verbose_name_plural': '品種マスタ',
+                'unique_together': {('crop', 'name')},
+            },
+        ),
+        migrations.CreateModel(
+            name='Plan',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('year', models.IntegerField(verbose_name='作付年度')),
+                ('notes', models.TextField(blank=True, null=True, verbose_name='備考')),
+                ('crop', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='plans', to='plans.crop', verbose_name='作物')),
+                ('field', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='plans', to='fields.field', verbose_name='圃場')),
+                ('variety', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='plans', to='plans.variety', verbose_name='品種')),
+            ],
+            options={
+                'verbose_name': '作付け計画',
+                'verbose_name_plural': '作付け計画',
+                'ordering': ['-year', 'field'],
+                'unique_together': {('field', 'year')},
+            },
+        ),
+    ]

backend/apps/plans/models.py

@@ -1,3 +1,43 @@
 from django.db import models
+from apps.fields.models import Field
 
-# Create your models here.
+
+class Crop(models.Model):
+    name = models.CharField(max_length=100, unique=True, verbose_name="作物名")
+
+    class Meta:
+        verbose_name = "作物マスタ"
+        verbose_name_plural = "作物マスタ"
+
+    def __str__(self):
+        return self.name
+
+
+class Variety(models.Model):
+    crop = models.ForeignKey(Crop, on_delete=models.CASCADE, related_name='varieties', verbose_name="作物")
+    name = models.CharField(max_length=100, verbose_name="品種名")
+
+    class Meta:
+        verbose_name = "品種マスタ"
+        verbose_name_plural = "品種マスタ"
+        unique_together = [['crop', 'name']]
+
+    def __str__(self):
+        return f"{self.crop.name} - {self.name}"
+
+
+class Plan(models.Model):
+    field = models.ForeignKey(Field, on_delete=models.CASCADE, related_name='plans', verbose_name="圃場")
+    year = models.IntegerField(verbose_name="作付年度")
+    crop = models.ForeignKey(Crop, on_delete=models.CASCADE, related_name='plans', verbose_name="作物")
+    variety = models.ForeignKey(Variety, on_delete=models.CASCADE, related_name='plans', verbose_name="品種")
+    notes = models.TextField(blank=True, null=True, verbose_name="備考")
+
+    class Meta:
+        verbose_name = "作付け計画"
+        verbose_name_plural = "作付け計画"
+        unique_together = [['field', 'year']]
+        ordering = ['-year', 'field']
+
+    def __str__(self):
+        return f"{self.field.name} - {self.year} - {self.crop.name}"