I want send POST request with axios(VueJS) and when Django server got a POST request then I want to get back that request message.
I tried make functions when got an POST request in Django server and then return JsonResponse({"response": "got post request"), safe=False)
JS function
sendMessage() {
axios({
method: "POST",
url: url,
data: this.message
})
.then(response => {
this.receive = response;
})
.catch(response => {
alert('Failed to POST.' + response);
})
}
}
views.py
from chat.serializer import chatSerializer
from chat.models import *
from rest_framework.routers import DefaultRouter
from rest_framework import viewsets
from django.http import JsonResponse
from django.views.generic import View
# Create your views here.
class get_post(View):
def post(self, request):
if request.method == 'POST':
JsonResponse({"response": 'got post request'}, safe=False)
but error says like that in django
Internal Server Error: /api/chat/
Traceback (most recent call last):
File "/usr/lib/python3/dist-packages/django/core/handlers/exception.py", line
47, in inner
response = get_response(request)
File "/usr/lib/python3/dist-packages/django/core/handlers/base.py", line 188,
in _get_response
self.check_response(response, callback)
File "/usr/lib/python3/dist-packages/django/core/handlers/base.py", line 309,
in check_response
raise ValueError(
ValueError: The view chat.views.views.get_post didn't return an HttpResponse object. It returned None instead.
[26/Oct/2022 17:06:51] "POST /api/chat/ HTTP/1.1" 500 60946
I think POST request is working properly, but Django code is something wrong.
Therefore, my question is..
How to fix and solve this error?
When I call axios in JS, inside '.then' we got a response so which data is come to this variable? Should I return this data like Response() or JsonResponse() method?
just add a return in the view ... like this:
class get_post(View):
def post(self, request):
if request.method == 'POST':
return JsonResponse({"response": 'got post request'}, safe=False)
because the error complains that the post function must return anything.
for the second question ya you need to return JsonResponse because you are dealing with APIs.
I followed this https://stackoverflow.com/a/31381075/10087274 because I want when url does not exist a json shows error but the problem is here that I get server error 500 when I add handler404 in my url dispatcher
here is my project url :
from django.urls import path, include
from django.conf.urls import handler404
from api.exception import custom404
handler404 = custom404
urlpatterns = [
path('api/v1/', include('acl.urls')),
]
and I have exception.py inside my project folder (near settings.py) contains this:
from django.http import JsonResponse
def custom404(request):
return JsonResponse({
'status_code': 404,
'error': 'The resource was not found'
})
I dont know how can I solve my problem
Unfortunately, you haven't provided much information regarding the error traceback. Anyway, The very first thing I noticed in your code, you've missed one optional parameter to the custom404 function. That function should take two parameters, request and exception
def custom404(request, exception=None):
response = {
'status_code': 404,
'error': 'The resource was not found'
}
return JsonResponse(response, status=404)
Reference
1. Custom Error Views
Well django rest framework is open source, so if you want to replicate certain behaviour you can read the code and pick and chose what you like. For instance, you can see that the Generic Error view (custom server and bad request error views) provided in drf docs are located inside exceptions.py inside rest_framework you can look it up here and see how it can be done.
Create a custom 404 view, like this:
def not_found(request, exception, *args, **kwargs):
""" Generic 404 error handler """
data = {
'error': 'Not Found (404)'
}
return JsonResponse(data, status=status.HTTP_404_NOT_FOUND)
I am making an api which return the JsonResponse as my text from the scrapy. When i run the scripts individually it runs perfectly. But when i try to integrate the scrapy script with python django i am not getting the output.
What i want is only return the response to the request(which in my case is POSTMAN POST request.
Here is the code which i am trying
from django.http import HttpResponse, JsonResponse
from django.views.decorators.csrf import csrf_exempt
import scrapy
from scrapy.crawler import CrawlerProcess
#csrf_exempt
def some_view(request, username):
process = CrawlerProcess({
'USER_AGENT': 'Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1)',
'LOG_ENABLED': 'false'
})
process_test = process.crawl(QuotesSpider)
process.start()
return JsonResponse({'return': process_test})
class QuotesSpider(scrapy.Spider):
name = "quotes"
def start_requests(self):
urls = [
'http://quotes.toscrape.com/random',
]
for url in urls:
yield scrapy.Request(url=url, callback=self.parse)
def parse(self, response):
return response.css('.text::text').extract_first()
I am very new to python and django stuff.Any kind of help would be much appreciated.
In your code, process_test is a CrawlerProcess, not the output from the crawling.
You need additional configuration to make your spider store its output "somewhere". See this SO Q&A about writing a custom pipeline.
If you just want to synchronously retrieve and parse a single page, you may be better off using requests to retrieve the page, and parsel to parse it.
Hi I'm trying to upload a file to server and I'm having difficulty sending the file. I'm using Django at the backend and I've already set up a put endpoint allowing users to send files and I confirmed it works as intended using postman. However, I'm having trouble uploading on the frontend. So this is how my code looks on the frontend end.
selectFileManually.addEventListener('change', function(event){
event.stopPropagation();
event.preventDefault();
axios.put('http://127.0.0.1:8000/api/v1/fileupload/', {
file: this.files[0]
}).then(resp => console.log(resp.data)).catch(err => console.log(err.response.data))
}
}
})
Here selectFileManually is an input[type='file']. However, when I send this request the server comes back with the following error: "Missing filename. Request should include a Content-Disposition header with a filename parameter and when I look at the payload it's complete empty: `{file: {}}' even though you can clearly see I provided a file to send. This is how my code looks at the backend
# views.py
from django.shortcuts import render
from rest_framework.views import APIView
from rest_framework.response import Response
from rest_framework.parsers import FileUploadParser, MultiPartParser
import os
# Create your views here.
BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
class FileUploadView(APIView):
parser_classes = (MultiPartParser, FileUploadParser, )
def put(self, request, format=None):
print(request.data)
with open(os.path.join(BASE_DIR, 'api/media', request.data['file'].name), 'wb') as f:
for chunk in request.data['file'].chunks():
f.write(chunk)
return Response(status=204)
#urls.py
from django.urls import path
from . import views
urlpatterns = [
path('fileupload/', views.FileUploadView.as_view()),
]
Could somebody please help me. I know that this.files[0] is not empty since the console logged the files and it showed me that it was indeed the right content
According to the docs, you need to specify a filename parameter for the view to handle the request. This can be done in two ways:
1. The view can be called using the filename URL keyword argument, then that argument is set as the filename.To achieve this you need to change your url pattern to
urlpatterns = [
path('fileupload/(?P<filename>[^/]+)$', views.FileUploadView.as_view()),
]
2. If the view is called without the filename URL keyword argument, then the client must set it in the Content-Disposition HTTP header. It is then handled by FileUploadParser in the views.
For eg Content-Disposition: attachment; filename=image.jpg.
Either way, you need to access filename while making a request.
In your case, since your url pattern does not contain a filename argument you need to set headers to include Content-Disposition.
Assuming this.files[0] is a fileObject, you can get filename by simply doing this.files[0].name. Now setting headers on the axios request, so your front end code should look like this.
selectFileManually.addEventListener('change', function(event){
event.stopPropagation();
event.preventDefault();
axios.put('http://127.0.0.1:8000/api/v1/fileupload/', {
file: this.files[0]
},{headers:{
'Content-Disposition': 'attachment; filename=this.files[0].name'
}
},
).then(resp => console.log(resp.data)).catch(err => console.log(err.response.data))
}
}
})
Hope this helps !
I am using Django for a project and is already in production.
In the production environment 500.html is rendered whenever a server error occurs.
How do I test the rendering of 500.html in dev environment? Or how do I render 500.html in dev, if I turn-off debug I still get the errors and not 500.html
background: I include some page elements based on a page and some are missing when 500.html is called and want to debug it in dev environment.
I prefer not to turn DEBUG off. Instead I put the following snippet in the urls.py:
if settings.DEBUG:
urlpatterns += patterns('',
(r'^500/$', 'your_custom_view_if_you_wrote_one'),
(r'^404/$', 'django.views.generic.simple.direct_to_template', {'template': '404.html'}),
)
In the snippet above, the error page uses a custom view, you can easily replace it with Django's direct_to_template view though.
Now you can test 500 and 404 pages by calling their urls: http://example.com/500 and http://example.com/404
In Django 1.6 django.views.generic.simple.direct_to_template does not exists anymore, these are my settings for special views:
# urls.py
from django.views.generic import TemplateView
from django.views.defaults import page_not_found, server_error
urlpatterns += [
url(r'^400/$', TemplateView.as_view(template_name='400.html')),
url(r'^403/$', TemplateView.as_view(template_name='403.html')),
url(r'^404/$', page_not_found),
url(r'^500/$', server_error),
]
And if you want to use the default Django 500 view instead of your custom view:
if settings.DEBUG:
urlpatterns += patterns('',
(r'^500/$', 'django.views.defaults.server_error'),
(r'^404/$', 'django.views.generic.simple.direct_to_template', {'template': '404.html'}),
)
Continuing shanyu's answer, in Django 1.3+ use:
if settings.DEBUG:
urlpatterns += patterns('',
(r'^500/$', 'django.views.defaults.server_error'),
(r'^404/$', 'django.views.defaults.page_not_found'),
)
For Django > 3.0, just set the raise_request_exception value to False.
from django.test import TestCase
class ViewTestClass(TestCase):
def test_error_page(self):
self.client.raise_request_exception = False
response = self.client.get(reverse('error-page'))
self.assertEqual(response.status_code, 500)
self.assertTrue(
'some text from the custom 500 page'
in response.content.decode('utf8'))
Documentation: https://docs.djangoproject.com/en/3.2/topics/testing/tools/
NOTE: if the error page raises an exception, that will show up as an ERROR in the test log. You can turn the test logging up to CRITICAL by default to suppress that error.
Are both debug settings false?
settings.DEBUG = False
settings.TEMPLATE_DEBUG = False
How i do and test custom error handlers
Define custom View based on TemplateView
# views.py
from django.views.generic import TemplateView
class ErrorHandler(TemplateView):
""" Render error template """
error_code = 404
template_name = 'index/error.html'
def dispatch(self, request, *args, **kwargs):
""" For error on any methods return just GET """
return self.get(request, *args, **kwargs)
def get_context_data(self, **kwargs):
context = super().get_context_data(**kwargs)
context['error_code'] = self.error_code
return context
def render_to_response(self, context, **response_kwargs):
""" Return correct status code """
response_kwargs = response_kwargs or {}
response_kwargs.update(status=self.error_code)
return super().render_to_response(context, **response_kwargs)
Tell django to use custom error handlers
# urls.py
from index.views import ErrorHandler
# error handing handlers - fly binding
for code in (400, 403, 404, 500):
vars()['handler{}'.format(code)] = ErrorHandler.as_view(error_code=code)
Testcase for custom error handlers
# tests.py
from unittest import mock
from django.test import TestCase
from django.core.exceptions import SuspiciousOperation, PermissionDenied
from django.http import Http404
from index import views
class ErrorHandlersTestCase(TestCase):
""" Check is correct error handlers work """
def raise_(exception):
def wrapped(*args, **kwargs):
raise exception('Test exception')
return wrapped
def test_index_page(self):
""" Should check is 200 on index page """
response = self.client.get('/')
self.assertEqual(response.status_code, 200)
self.assertTemplateUsed(response, 'index/index.html')
#mock.patch('index.views.IndexView.get', raise_(Http404))
def test_404_page(self):
""" Should check is 404 page correct """
response = self.client.get('/')
self.assertEqual(response.status_code, 404)
self.assertTemplateUsed(response, 'index/error.html')
self.assertIn('404 Page not found', response.content.decode('utf-8'))
#mock.patch('index.views.IndexView.get', views.ErrorHandler.as_view(error_code=500))
def test_500_page(self):
""" Should check is 500 page correct """
response = self.client.get('/')
self.assertEqual(response.status_code, 500)
self.assertTemplateUsed(response, 'index/error.html')
self.assertIn('500 Server Error', response.content.decode('utf-8'))
#mock.patch('index.views.IndexView.get', raise_(SuspiciousOperation))
def test_400_page(self):
""" Should check is 400 page correct """
response = self.client.get('/')
self.assertEqual(response.status_code, 400)
self.assertTemplateUsed(response, 'index/error.html')
self.assertIn('400 Bad request', response.content.decode('utf-8'))
#mock.patch('index.views.IndexView.get', raise_(PermissionDenied))
def test_403_page(self):
""" Should check is 403 page correct """
response = self.client.get('/')
self.assertEqual(response.status_code, 403)
self.assertTemplateUsed(response, 'index/error.html')
self.assertIn('403 Permission Denied', response.content.decode('utf-8'))
urls.py
handler500 = 'project.apps.core.views.handler500'
handler404 = 'project.apps.core.views.handler404'
views.py
from django.template.loader import get_template
from django.template import Context
from django.http import HttpResponseServerError, HttpResponseNotFound
def handler500(request, template_name='500.html'):
t = get_template(template_name)
ctx = Context({})
return HttpResponseServerError(t.render(ctx))
def handler404(request, template_name='404.html'):
t = get_template(template_name)
ctx = Context({})
return HttpResponseNotFound(t.render(ctx))
tests.py
from django.test import TestCase
from django.test.client import RequestFactory
from project import urls
from ..views import handler404, handler500
class TestErrorPages(TestCase):
def test_error_handlers(self):
self.assertTrue(urls.handler404.endswith('.handler404'))
self.assertTrue(urls.handler500.endswith('.handler500'))
factory = RequestFactory()
request = factory.get('/')
response = handler404(request)
self.assertEqual(response.status_code, 404)
self.assertIn('404 Not Found!!', unicode(response))
response = handler500(request)
self.assertEqual(response.status_code, 500)
self.assertIn('500 Internal Server Error', unicode(response))
Update for Django > 1.6 and without getting
page_not_found() missing 1 required positional argument: 'exception'
Inspired by this answer:
# urls.py
from django.views.defaults import page_not_found, server_error, permission_denied, bad_request
[...]
if settings.DEBUG:
# This allows the error pages to be debugged during development, just visit
# these url in browser to see how these error pages look like.
urlpatterns += [
path('400/', bad_request, kwargs={'exception': Exception('Bad Request!')}),
path('403/', permission_denied, kwargs={'exception': Exception('Permission Denied')}),
path('404/', page_not_found, kwargs={'exception': Exception('Page not Found')}),
path('500/', server_error),
You can simply define the handler404 and handler500 for errors in your main views.py file as detailed in this answer:
https://stackoverflow.com/a/18009660/1913888
This will return the error that you desire when Django routes to that handler. No custom URL configuration is needed to route to a different URL name.
In Django versions < 3.0, you should do as follows:
client.py
from django.core.signals import got_request_exception
from django.template import TemplateDoesNotExist
from django.test import signals
from django.test.client import Client as DjangoClient, store_rendered_templates
from django.urls import resolve
from django.utils import six
from django.utils.functional import SimpleLazyObject, curry
class Client(DjangoClient):
"""Test client that does not raise Exceptions if requested."""
def __init__(self,
enforce_csrf_checks=False,
raise_request_exception=True, **defaults):
super(Client, self).__init__(enforce_csrf_checks=enforce_csrf_checks,
**defaults)
self.raise_request_exception = raise_request_exception
def request(self, **request):
"""
The master request method. Composes the environment dictionary
and passes to the handler, returning the result of the handler.
Assumes defaults for the query environment, which can be overridden
using the arguments to the request.
"""
environ = self._base_environ(**request)
# Curry a data dictionary into an instance of the template renderer
# callback function.
data = {}
on_template_render = curry(store_rendered_templates, data)
signal_uid = "template-render-%s" % id(request)
signals.template_rendered.connect(on_template_render,
dispatch_uid=signal_uid)
# Capture exceptions created by the handler.
exception_uid = "request-exception-%s" % id(request)
got_request_exception.connect(self.store_exc_info,
dispatch_uid=exception_uid)
try:
try:
response = self.handler(environ)
except TemplateDoesNotExist as e:
# If the view raises an exception, Django will attempt to show
# the 500.html template. If that template is not available,
# we should ignore the error in favor of re-raising the
# underlying exception that caused the 500 error. Any other
# template found to be missing during view error handling
# should be reported as-is.
if e.args != ('500.html',):
raise
# Look for a signalled exception, clear the current context
# exception data, then re-raise the signalled exception.
# Also make sure that the signalled exception is cleared from
# the local cache!
response.exc_info = self.exc_info # Patch exception handling
if self.exc_info:
exc_info = self.exc_info
self.exc_info = None
if self.raise_request_exception: # Patch exception handling
six.reraise(*exc_info)
# Save the client and request that stimulated the response.
response.client = self
response.request = request
# Add any rendered template detail to the response.
response.templates = data.get("templates", [])
response.context = data.get("context")
response.json = curry(self._parse_json, response)
# Attach the ResolverMatch instance to the response
response.resolver_match = SimpleLazyObject(
lambda: resolve(request['PATH_INFO'])
)
# Flatten a single context. Not really necessary anymore thanks to
# the __getattr__ flattening in ContextList, but has some edge-case
# backwards-compatibility implications.
if response.context and len(response.context) == 1:
response.context = response.context[0]
# Update persistent cookie data.
if response.cookies:
self.cookies.update(response.cookies)
return response
finally:
signals.template_rendered.disconnect(dispatch_uid=signal_uid)
got_request_exception.disconnect(dispatch_uid=exception_uid)
tests.py
from unittest import mock
from django.contrib.auth import get_user_model
from django.core.urlresolvers import reverse
from django.test import TestCase, override_settings
from .client import Client # Important, we use our own Client here!
class TestErrors(TestCase):
"""Test errors."""
#classmethod
def setUpClass(cls):
super(TestErrors, cls).setUpClass()
cls.username = 'admin'
cls.email = 'admin#localhost'
cls.password = 'test1234test1234'
cls.not_found_url = '/i-do-not-exist/'
cls.internal_server_error_url = reverse('password_reset')
def setUp(self):
super(TestErrors, self).setUp()
User = get_user_model()
User.objects.create_user(
self.username,
self.email,
self.password,
is_staff=True,
is_active=True
)
self.client = Client(raise_request_exception=False)
# Mock in order to trigger Exception and resulting Internal server error
#mock.patch('django.contrib.auth.views.PasswordResetView.form_class', None)
#override_settings(DEBUG=False)
def test_errors(self):
self.client.login(username=self.username, password=self.password)
with self.subTest("Not found (404)"):
response = self.client.get(self.not_found_url, follow=True)
self.assertNotIn('^admin/', str(response.content))
with self.subTest("Internal server error (500)"):
response = self.client.get(self.internal_server_error_url,
follow=True)
self.assertNotIn('TypeError', str(response.content))
Starting from Django 3.0 you could skip the custom Client definition and just use the code from tests.py.