Django REST framework API occurs ConnectionDoesNotExist - django

Question

I am learning the decoupled Django with Django-rest-framework and React for web development. The database is PostgreSQL.
I have configured API, and when I run http://127.0.0.1:8000/api, it looks fine:
enter image description here
But if I click the link in this API(http://127.0.0.1:8000/api/todos/), it fails:
enter image description here
I can't figure out what is going on.
my backend/urls.py is:
from django.conf.urls import include, url
from django.contrib import admin
from rest_framework import routers
from todos import views
router = routers.DefaultRouter()
router.register(r'todos', views.TodoView,'todo')
urlpatterns = [
# url(r'^', include('todos.urls')),
url(r'^api/', include(router.urls)),
url(r'^admin/', include(admin.site.urls)),
]
my backend/settings.py is:
# Build paths inside the project like this: os.path.join(BASE_DIR, ...)
import os
BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
# Quick-start development settings - unsuitable for production
# See https://docs.djangoproject.com/en/1.8/howto/deployment/checklist/
# SECURITY WARNING: keep the secret key used in production secret!
SECRET_KEY = 'igphn#&4b(67(*=!u)lr1wr=jtfhvgwc03nl&5+t7m18%-#ttm'
# SECURITY WARNING: don't run with debug turned on in production!
DEBUG = True
ALLOWED_HOSTS = []
# Application definition
INSTALLED_APPS = (
'django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'rest_framework',
'todos',
'corsheaders',
)
MIDDLEWARE_CLASSES = (
'django.contrib.sessions.middleware.SessionMiddleware',
'django.middleware.common.CommonMiddleware',
'django.middleware.csrf.CsrfViewMiddleware',
'django.contrib.auth.middleware.AuthenticationMiddleware',
'django.contrib.auth.middleware.SessionAuthenticationMiddleware',
'django.contrib.messages.middleware.MessageMiddleware',
'django.middleware.clickjacking.XFrameOptionsMiddleware',
'django.middleware.security.SecurityMiddleware',
'corsheaders.middleware.CorsMiddleware',
)
ROOT_URLCONF = 'backend.urls'
TEMPLATES = [
{
'BACKEND': 'django.template.backends.django.DjangoTemplates',
'DIRS': [],
'APP_DIRS': True,
'OPTIONS': {
'context_processors': [
'django.template.context_processors.debug',
'django.template.context_processors.request',
'django.contrib.auth.context_processors.auth',
'django.contrib.messages.context_processors.messages',
],
},
},
]
WSGI_APPLICATION = 'backend.wsgi.application'
# Database
# https://docs.djangoproject.com/en/1.8/ref/settings/#databases
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.postgresql_psycopg2',
'NAME': 'todos',
'USER': 'luyaoye',
'PASSWORD': '1234567',
'HOST': 'localhost',
'PORT':'5432'
}
}
# Internationalization
# https://docs.djangoproject.com/en/1.8/topics/i18n/
LANGUAGE_CODE = 'en-us'
TIME_ZONE = 'UTC'
USE_I18N = True
USE_L10N = True
USE_TZ = True
# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/1.8/howto/static-files/
STATIC_URL = '/static/'
# whitelist localhost:3000 where frontend will be served
CORS_ORIGIN_WHITELIST = ('localhost:3000/')
REST_FRAMEWORK = {
'DEFAULT_PAGINATION_CLASS': 'rest_framework.pagination.PageNumberPagination',
'PAGE_SIZE': 20
}
my todos/serializers.py is:
from rest_framework import serializers
from .models import Todos
class TodoSerializer(serializers.HyperlinkedModelSerializer):
class Meta:
model=Todos
fields=['id','title','notes','created_at','completed',]
my todos/views.py is:
from django.shortcuts import render
from rest_framework import viewsets
from .serializers import TodoSerializer
from .models import Todos
class TodoView(viewsets.ModelViewSet):
serializer_class = TodoSerializer
queryset = Todos.objects.using('todos').all()
my todos/models.py is:
from django.db import models
class Todos(models.Model):
title = models.CharField(max_length=100,blank=False)
notes = models.CharField(max_length=1000, blank=True)
created_at = models.DateTimeField(auto_now_add=True)
completed = models.BooleanField(default=False)
def __str__(self):
# display todos brief
return self.title
My PostgreSQL database is running locally as well, and having data:
enter image description here
Anyone can help??

Answer 1

In queryset property of your TodoView, you don't have to write using('todos') part.
using() is meant for applications with multiple databases and tells django to use different DB connection (it uses DATABASES['default'] by default).
https://docs.djangoproject.com/en/2.2/topics/db/multi-db/#manually-selecting-a-database-for-a-queryset
So if you remove using part - everything should be working.