From f0749a6b2590e932b725115009e3b06210e0a699 Mon Sep 17 00:00:00 2001
From: Ivlev Denis <di-erz@yandex.ru>
Date: Fri, 2 Mar 2018 10:18:05 +0300
Subject: [PATCH 1/3] Filter AuthorBalance by author id

---
 api/v1/views.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/api/v1/views.py b/api/v1/views.py
index 6958934c..bca328a2 100644
--- a/api/v1/views.py
+++ b/api/v1/views.py
@@ -45,7 +45,7 @@ class AuthorBalanceViewSet(ExtendedModelViewSet):
     queryset = AuthorBalance.objects.all()
     serializer_class = AuthorBalanceSerializer
     permission_classes = (IsAdmin,)
-    filter_fields = ('status', 'type')
+    filter_fields = ('author', 'status', 'type')
     search_fields = (
         'author__email',
         'author__first_name',

From 79bc43f8cd3db5315dbac9608f5247d7e8d03305 Mon Sep 17 00:00:00 2001
From: Ivlev Denis <di-erz@yandex.ru>
Date: Fri, 2 Mar 2018 10:19:32 +0300
Subject: [PATCH 2/3] Set nullable cause field of AuthorBalance

---
 apps/payment/models.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/apps/payment/models.py b/apps/payment/models.py
index e25fb6ab..dc8426dd 100644
--- a/apps/payment/models.py
+++ b/apps/payment/models.py
@@ -34,7 +34,7 @@ class AuthorBalance(models.Model):
     commission = models.DecimalField('Комиссия', max_digits=8, decimal_places=2, default=0)
     status = models.PositiveSmallIntegerField('Статус', choices=STATUS_CHOICES, default=0)
     payment = models.OneToOneField('Payment', on_delete=models.CASCADE, null=True, blank=True, verbose_name='Платёж')
-    cause = models.TextField('Причина отказа', default='')
+    cause = models.TextField('Причина отказа', null=True, blank=True)
 
     class Meta:
         verbose_name = 'Баланс'

From 8603a92e101b3042e0a4535319b44dc2b06856f1 Mon Sep 17 00:00:00 2001
From: Ivlev Denis <di-erz@yandex.ru>
Date: Fri, 2 Mar 2018 10:24:08 +0300
Subject: [PATCH 3/3] Fix AuthorBalanceSerializer

---
 api/v1/serializers/payment.py | 28 ++++++++++++++++++++++++++++
 api/v1/views.py               |  7 +++++--
 2 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/api/v1/serializers/payment.py b/api/v1/serializers/payment.py
index 93400cbf..9174177d 100644
--- a/api/v1/serializers/payment.py
+++ b/api/v1/serializers/payment.py
@@ -1,9 +1,37 @@
 from rest_framework import serializers
 
 from apps.payment.models import AuthorBalance
+from .user import UserSerializer
+
+
+class AuthorBalanceCreateSerializer(serializers.ModelSerializer):
+
+    class Meta:
+        model = AuthorBalance
+        fields = (
+            'id',
+            'author',
+            'type',
+            'amount',
+            'commission',
+            'status',
+            'payment',
+            'cause',
+        )
+
+        read_only_fields = (
+            'id',
+            'author',
+            'type',
+            'payment',
+        )
+
+    def to_representation(self, instance):
+        return AuthorBalanceSerializer(instance, context=self.context).to_representation(instance)
 
 
 class AuthorBalanceSerializer(serializers.ModelSerializer):
+    author = UserSerializer()
 
     class Meta:
         model = AuthorBalance
diff --git a/api/v1/views.py b/api/v1/views.py
index bca328a2..ad4b1402 100644
--- a/api/v1/views.py
+++ b/api/v1/views.py
@@ -24,7 +24,7 @@ from .serializers.content import (
     ImageObjectSerializer,
 )
 from .serializers.school import SchoolScheduleSerializer
-from .serializers.payment import AuthorBalanceSerializer
+from .serializers.payment import AuthorBalanceSerializer, AuthorBalanceCreateSerializer
 from .serializers.user import (
     UserSerializer, UserPhotoSerializer,
 )
@@ -43,7 +43,10 @@ User = get_user_model()
 
 class AuthorBalanceViewSet(ExtendedModelViewSet):
     queryset = AuthorBalance.objects.all()
-    serializer_class = AuthorBalanceSerializer
+    serializer_class = AuthorBalanceCreateSerializer
+    serializer_class_map = {
+        'list': AuthorBalanceSerializer,
+    }
     permission_classes = (IsAdmin,)
     filter_fields = ('author', 'status', 'type')
     search_fields = (