Add Source model

Starts the process of adding support for single-item submissions by introducing
a model that can connect a `FacilityListItem` to a `Contributor` without needing
a `FacilityList`

`FacilityListItem.source` is nullable for now to make the migration backward
compatible.

src/django/api/migrations/0035_add_source_20190926_2048.py

@@ -0,0 +1,33 @@
+# Generated by Django 2.2.3 on 2019-10-01 15:31
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('api', '0034_facilitylocation'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='Source',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('source_type', models.CharField(choices=[('LIST', 'LIST'), ('SINGLE', 'SINGLE')], help_text='Did the the facility data arrive in a list or a single item', max_length=6)),
+                ('is_active', models.BooleanField(default=True, help_text='True if items from the source should be shown as being associated with the contributor')),
+                ('is_public', models.BooleanField(default=True, help_text='True if the public can see factories from this list are associated with the contributor.')),
+                ('create', models.BooleanField(default=True, help_text='Should a facility or facility match be created from the facility data')),
+                ('created_at', models.DateTimeField(auto_now_add=True)),
+                ('updated_at', models.DateTimeField(auto_now=True)),
+                ('contributor', models.ForeignKey(help_text='The contributor who submitted the facility data', null=True, on_delete=django.db.models.deletion.SET_NULL, to='api.Contributor')),
+                ('facility_list', models.OneToOneField(help_text='The related list if the type of the source is LIST.', null=True, on_delete=django.db.models.deletion.PROTECT, to='api.FacilityList')),
+            ],
+        ),
+        migrations.AddField(
+            model_name='facilitylistitem',
+            name='source',
+            field=models.ForeignKey(blank=True, help_text='The source from which this item was created.', null=True, on_delete=django.db.models.deletion.PROTECT, to='api.Source'),
+        ),
+    ]

src/django/api/models.py

@@ -209,6 +209,59 @@ def did_register_and_confirm_email(self):
             return True
 
 
+class Source(models.Model):
+    LIST = 'LIST'
+    SINGLE = 'SINGLE'
+
+    SOURCE_TYPE_CHOICES = (
+        (LIST, LIST),
+        (SINGLE, SINGLE),
+    )
+
+    contributor = models.ForeignKey(
+        'Contributor',
+        null=True,
+        on_delete=models.SET_NULL,
+        help_text='The contributor who submitted the facility data'
+    )
+    source_type = models.CharField(
+        null=False,
+        max_length=6,
+        choices=SOURCE_TYPE_CHOICES,
+        help_text='Did the the facility data arrive in a list or a single item'
+    )
+    facility_list = models.OneToOneField(
+        'FacilityList',
+        null=True,
+        on_delete=models.PROTECT,
+        help_text='The related list if the type of the source is LIST.'
+    )
+    is_active = models.BooleanField(
+        null=False,
+        default=True,
+        help_text=('True if items from the source should be shown as being '
+                   'associated with the contributor')
+    )
+    is_public = models.BooleanField(
+        null=False,
+        default=True,
+        help_text=('True if the public can see factories from this list '
+                   'are associated with the contributor.')
+    )
+    create = models.BooleanField(
+        null=False,
+        default=True,
+        help_text=('Should a facility or facility match be created from the '
+                   'facility data')
+    )
+    created_at = models.DateTimeField(auto_now_add=True)
+    updated_at = models.DateTimeField(auto_now=True)
+
+    def __str__(self):
+        return '{0} ({1})'.format(
+            self.contributor.name, self.id)
+
+
 class FacilityList(models.Model):
     """
     Metadata for an uploaded list of facilities.
@@ -320,6 +373,13 @@ class Meta:
         'FacilityList',
         on_delete=models.CASCADE,
         help_text='The list that this line item is a part of.')
+    source = models.ForeignKey(
+        'Source',
+        null=True,
+        blank=True,
+        on_delete=models.PROTECT,
+        help_text='The source from which this item was created.'
+    )
     row_index = models.IntegerField(
         null=False,
         editable=False,