Enforce unique AuthServicesInfo (#618)

Alter user field to OneToOneField
Migration to enforce uniqueness pre-change
Migration to ensure all users have an AuthServicesInfo
Receiver to automatically create one upon user creation
Replace AuthServicesInfo.get_or_create with get
Prevent deletion of AuthServicesInfo from admin site
Remove add and delete permissions from model.

Get character names in chunks on corpstats update to prevent HTTP400 when requesting >350(ish) names

Include corpstats docs.
Update settings docs.

authentication/migrations/0008_set_state.py

@@ -24,7 +24,7 @@ def determine_membership_by_character(char, apps):
 
 def determine_membership_by_user(user, apps):
     AuthServicesInfo = apps.get_model('authentication', 'AuthServicesInfo')
-    auth, c = AuthServicesInfo.objects.get_or_create(user=user)
+    auth = AuthServicesInfo.objects.get(user=user)
     if auth.main_char_id:
         EveCharacter = apps.get_model('eveonline', 'EveCharacter')
         if EveCharacter.objects.filter(character_id=auth.main_char_id).exists():
@@ -41,7 +41,7 @@ def set_state(user, apps):
     else:
         state = NONE_STATE
     AuthServicesInfo = apps.get_model('authentication', 'AuthServicesInfo')
-    auth = AuthServicesInfo.objects.get_or_create(user=user)[0]
+    auth = AuthServicesInfo.objects.get(user=user)
     if auth.state != state:
        auth.state = state
        auth.save()

authentication/migrations/0010_only_one_authservicesinfo.py

@@ -0,0 +1,40 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.10.1 on 2017-01-07 06:47
+from __future__ import unicode_literals
+
+from django.db import migrations
+
+def count_completed_fields(model):
+    return len([True for key, value in model.__dict__.items() if bool(value)])
+
+def forward(apps, schema_editor):
+    # this ensures only one model exists per user
+    AuthServicesInfo = apps.get_model('authentication', 'AuthServicesInfo')
+    users = set([a.user for a in AuthServicesInfo.objects.all()])
+    for u in users:
+        auths = AuthServicesInfo.objects.filter(user=u)
+        if auths.count() > 1:
+            pk = auths[0].pk
+            largest = 0
+            for auth in auths:
+                completed = count_completed_fields(auth)
+                if completed > largest:
+                    largest = completed
+                    pk = auth.pk
+            auths.exclude(pk=pk).delete()
+
+    # ensure all users have a model
+    User = apps.get_model('auth', 'User')
+    for u in User.objects.exclude(pk__in=[user.pk for user in users]):
+        AuthServicesInfo.objects.create(user=u)
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('authentication', '0009_auto_20161021_0228'),
+    ]
+
+    operations = [
+        migrations.RunPython(forward, migrations.RunPython.noop)
+    ]

authentication/migrations/0011_authservicesinfo_user_onetoonefield.py

@@ -0,0 +1,22 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.10.1 on 2017-01-07 07:11
+from __future__ import unicode_literals
+
+from django.conf import settings
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('authentication', '0010_only_one_authservicesinfo'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='authservicesinfo',
+            name='user',
+            field=models.OneToOneField(on_delete=django.db.models.deletion.CASCADE, to=settings.AUTH_USER_MODEL),
+        ),
+    ]

authentication/migrations/0012_remove_add_delete_authservicesinfo_permissions.py

@@ -0,0 +1,39 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.10.5 on 2017-01-12 00:59
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+def remove_permissions(apps, schema_editor):
+    ContentType = apps.get_model('contenttypes', 'ContentType')
+    Permission = apps.get_model('auth', 'Permission')
+    AuthServicesInfo = apps.get_model('authentication', 'AuthServicesInfo')
+
+    # delete the add and remove permissions for AuthServicesInfo
+    ct = ContentType.objects.get_for_model(AuthServicesInfo)
+    Permission.objects.filter(content_type=ct).filter(codename__in=['add_authservicesinfo', 'delete_authservicesinfo']).delete()
+
+
+def add_permissions(apps, schema_editor):
+    ContentType = apps.get_model('contenttypes', 'ContentType')
+    Permission = apps.get_model('auth', 'Permission')
+    AuthServicesInfo = apps.get_model('authentication', 'AuthServicesInfo')
+
+    # recreate the add and remove permissions for AuthServicesInfo
+    ct = ContentType.objects.get_for_model(AuthServicesInfo)
+    Permission.objects.create(content_type=ct, codename='add_authservicesinfo', name='Can add auth services info')
+    Permission.objects.create(content_type=ct, codename='delete_authservicesinfo', name='Can delete auth services info')
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('authentication', '0011_authservicesinfo_user_onetoonefield'),
+    ]
+
+    operations = [
+        migrations.AlterModelOptions(
+            name='authservicesinfo',
+            options={'default_permissions': ('change',)},
+        ),
+        migrations.RunPython(remove_permissions, add_permissions),
+    ]