Django community: Django Q&A RSS
This page, updated regularly, aggregates Django Q&A from the Django community.
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What does the error RuntimeError: populate() isn't reentrant mean
To be specific, I have a standalone script in my django app folder, which is accessing the models,as per the django docs here you have to do the following configuration: import os import django os.environ['DJANGO_SETTINGS_MODULE'] = settings_file django.setup() But when i run the server i get the error RuntimeError: populate() isn't reentrant -
UnicodeEncodeError: 'charmap' codec can't encode character - Python Report CSS
I know this kind of question has been asked before but nothing worked for me. I'm trying to generate some PDF report using weasyprint. Here is my code; htmlContent = py_str["htmlContent"] HTML(string=htmlContent).write_pdf(target=response, stylesheets=[CSS(string=getCSS())]) but it doesn't generate any PDF. On debugging I found out that issue is in this getCSS() function that returns css string. By print this funtion on console, I'm getting this error UnicodeEncodeError: 'charmap' codec can't encode character '\x91' in position 5042: character maps to <undefined> this is CSS that I've from line number 5040 to 5042 .nav-pills > li { float: left; } All solutions that I found out are related to utf-8 but I could not understand where to use this utf-8 in my code. I'm totally stuck here. Any kind of help will be appreciated. I can add full css if needed. -
Docker-Compose + Django + PostgreSQL + uwsgi + Nginx getting 404 not found
I have recently make some service for practice. I used Docker-Compose, Django, PostgreSQL, uwsgi, Nginx. I try to run in my local machine. Here is what my site like when I access it on my server. Here is part of about static my settings.py file in the Django 'django_project' root directory. # STATIC FILE CONFIGURATION STATIC_DIR = SRC_DIR.path('static') STATIC_ROOT = str(SRC_DIR('staticfiles')) STATIC_URL = '/static/' STATICFILES_DIRS = [str(SRC_DIR('static'))] STATICFILES_FINDERS = ( 'django.contrib.staticfiles.finders.FileSystemFinder', 'django.contrib.staticfiles.finders.AppDirectoriesFinder', ) Here is my Docker-compose file version: '2' services: nginx: restart: always build: ./nginx ports: - "80:80" volumes_from: - refrigerator links: - refrigerator:refrigerator depends_on: - refrigerator refrigeratordb: image: "postgres:9.6.1" container_name: refrigeratordb expose: - "5432" environment: POSTGRES_PASSWORD: "something" POSTGRES_USER: "something" POSTGRES_DB: "something" refrigerator: build: . container_name: refrigeratormanager depends_on: - refrigeratordb links: - refrigeratordb volumes: - .:/var/www/refrigerator - /usr/src/app/static command: uwsgi --ini ./refrigerator_manager_uwsgi.ini stdin_open: true tty: true Here is my Dockerfile for Django FROM centos/python-36-centos7:latest USER root ADD . /var/www/refrigerator/ WORKDIR /var/www/refrigerator RUN pip install --upgrade pip RUN pip install -r requirements.txt EXPOSE 8000 Here is my Dockerfile for Nginx FROM nginx:alpine RUN rm /etc/nginx/conf.d/default.conf COPY ./sites-enabled/nginx.conf /etc/nginx/conf.d/default.conf Here is my nginx.conf server { listen 80; server_name sodwkdrhdjemals.com www.sodwkdrhdjemals.com; charset utf-8; location /static { alias /static; } location / { ... -
Calling image of nth model in template
I'm passing 5 headshots and 5 testimonials to a template in my context using the following: context = { 'headshots': headshots, 'testimonials', testimonials, } Each instance of the headshot model has a field of image. Within the template, I want to write each image using the forloop counter. {% for t in testimonials %} {{ t.body }} <img src="{{ headshots[forloop.counter].image }}" {% endfor %} My syntax appears to be wrong and the code in the tag is throwing an error. Any thoughts as to where I've gone wrong? Thanks! -
Django Rest Framework Nested Serializers
I am currently having trouble executing two layered nesting with django rest framework. I have read the DRF docs with nested relationships here http://www.django-rest-framework.org/api-guide/relations/ and have succesfully done the first layer which is to show styles with many colors in JSON. Not sure how to chain another layer though. Any help would be appreciated. Thanks in advance! The result I would like looks something like this: [ { style: ABC123, colors: [ {name: 'Red', sizes: [ {name: 'S'}, {name: 'M'} ], {name: 'Orange', sizes: [ {name: 'L'}, {name: 'XL'} ] ],... } ] Specifically, I would like to show that each style has a set of colors attributed to it, and each style-color combination has a set of sizes attributed to it. Below is my current models.py I've used intermediate table because I plan to add further complexities in the future (e.g. in style-color I would like to attach location of the colored picture and in style-color-size I will attach measurements) class Style(models.Model): name = models.CharField(max_length=36, unique=True) colors = models.ManyToManyField('Color', through='StyleColor') sizes = models.ManyToManyField('Size', through='StyleColorSize') class Color(models.Model): name = models.CharField(max_length=36, unique=True) class Size(models.Model): name = models.CharField(max_length=12, unique=True) class StyleColor(models.Model): style = models.ForeignKey('Style', on_delete=models.CASCADE) color = models.ForeignKey('Color', on_delete=models.CASCADE) class Meta: unique_together ... -
Django: How can I give certain objects unique urls without errors (e.g. mysite.com/object)
I'm wanting to make urls like this: path('<slug:slug>/', login_required(views.CompanyDetailView.as_view()), name='company_detail'), But it leads to errors, like 404s become "No company found for that slug," and other errors. So I am having to do this, like reddit: path('c/<slug:slug>/', login_required(views.CompanyDetailView.as_view()),name='company_detail'), How can I make my urls like my first snippet of code without errors? -
A Complete guide to publish a news website
Am a beginner in front end and back-end , so please don't downvote this question. I have thought of building a news website as a project to learn front-end and back-end as well. So I need a complete guide / walkthrough. Like storing news article in database , a common template for all the news articles.. and any extra things needed -
django ValueError: invalid literal for int() with base 10:
I'm trying to make a query to the Preferences table I have in django, but whenever I try to do a lookup to find a users entry, it just gives me this error. ValueError: invalid literal for int() with base 10: 'jason' The lookup I'm doing is this. Preferences.objects.filter(customer='jason') I can do this though which is odd. Preferences.objects.all() And I retrieve the query set of the one object I want. When I ask Preferences.objects.all()[0].customer And here I do retrieve the string 'Jason'. Can you explain what's going wrong either in my query or in the code? Any help would be appreciated and I can give other parts of code if needed! #models.py class Preferences(models.Model): customer = models.OneToOneField(User, on_delete=models.CASCADE) ebay_token = models.TextField(max_length=1024) app_id = models.CharField(max_length=128, default='asdf', editable=False) dev_id = models.CharField(max_length=128, default='1234', editable=False) cert_id = models.CharField(max_length=128, default='1234', editable=False) #this might need to be correct. I'm not sure if the user should have this much control over markup markup = models.FloatField(max_length=3, validators=[MaxValueValidator(50, message='Can\'t be this high!'), MinValueValidator(1, message='Can\'t be this low!')]) seller_location = models.CharField(max_length=256) #the ebay site number might need editing ebay_site_number = models.IntegerField() quantity = models.IntegerField(validators=[MinValueValidator(1, message='Must be atleast 1'), MaxValueValidator(10, message='Must be equal to or smaller than 10')]) #this will def ... -
DRF one to many serialization -- AttributeError from missing field
Error: AttributeError at /stats/matches Got AttributeError when attempting to get a value for field players on serializer MatchSerializer. The serializer field might be named incorrectly and not match any attribute or key on the Match instance. Original exception text was: 'Match' object has no attribute 'players'. Models: Every Match has 10 players. class Match(models.Model): tournament = models.ForeignKey(Tournament, blank=True) mid = models.CharField(primary_key=True, max_length=255) mlength = models.CharField(max_length=255) win_rad = models.BooleanField(default=True) class Player(models.Model): match = models.ForeignKey(Match, on_delete=models.CASCADE) playerid = models.CharField(max_length=255, default='novalue') # There is also a Meta class that defines unique_together but its omitted for clarity. Serializers: class PlayerSerializer(serializers.ModelSerializer): class Meta: model = Player fields = "__all__" class MatchSerializer(serializers.ModelSerializer): players = PlayerSerializer(many=True) class Meta: model = Match fields = ("mid","players") -
Deleting model instance on save if field in model is null
I've got a model called Service. Upon the user saving the model form, I'd like the model instance to be deleted if the body is null. Here is my code. class Service(models.Model): user = models.ForeignKey(User, on_delete=models.CASCADE, default=None) heading = models.CharField(max_length=60, null=True, blank=True) body = models.TextField(max_length=5000, null=True, blank=True) price = models.CharField(max_length=100, null=True, blank=True) def __str__(self): return self.user.username def save(self, *args, **kwargs): if self.body == None: #also tried if bool(self.body) == False: self.delete() else: pass This code is not successful at deleting the model instance when body is null (or blank). Do you know where I've gone wrong? Thanks! -
Oraginizing django urlpatterns for APIs
I would like to use an api version index for all my API endpoints (api/v1/). Currently I'm achieving it by structuring my urlpatterns like so: urlpatterns = [ path('api/v1/units/', include('units.api.urls')), path('api/v1/accounts/', include('accounts.api.urls')), ] Is there a way to organize this more elegantly? Ideally I would like it to look something like this: apipatterns = [ 'units/', include('units.api.urls'), 'accounts/', include('accounts.api.urls') ] urlpatterns = [ path('api/v1/', include(apipatterns)), ] -
Post_save in django is being called twice when using objects.create(...) method
In django post_save signal we can know if an object is new or modified using the created flag. But, the post_save signal is called twice when create an object using objects.create method, Where the create method does init then save(). The post save has created = False when it is called using init and it gets to be created=True after saving the object, How can I differentiate between an object is being modified and then saved or an object is being initialized? Here is a link to an old question, but it does not answer my question: Django post save signal getting called twice despite uid -
Adding Django CMS to an existing Django site. Can it damage the existing site and data?
A friend asked if they could/update their existing site to Django CMS It has a n e-commerce section added to it and apparently uses the Maris DB. He wants to use Django CMS mostly to easily add articles and other content. How intrusive or dangerous is it to install Django CMS to an already existing Django site especially it's customized existing e-commerce section? Thank you. -
Enable dirty reads for single transaction in Django
I'm building a REST API in Django where users can run tasks for objects. I've created a simple example below where I use transactions to easily rollback the state of the object in case the task fails. from django.db import IntegrityError, transaction def send_object(id): obj = MyModel.objects.get(pk=id) if obj.state != 'Created': raise ValueError('Object not in state "Created"') with transaction.atomic(): obj.state = 'Sending' obj.save() # send the object... obj.state = 'Sent' obj.save() Now I want the state of the object to be visible for users through the API while the task is running. Since the transaction isn't commited until the task is done, users only see the current state before and after the task. I need some sort of transaction in case of a system failure/shutdown occurs during the task and the object gets stuck at 'Sending'. The state must be reset so that the task easily can be retried. The isolation level is set to READ COMMITTED and cannot be changed without updating other parts of the code. Can I make the new state available before the transaction is commited (i.e. enable dirty reads) for just this transaction? Or is there something else I can do? -
The empty path didn't match any of these - Django 2 By Example
I am trying to complete the Django Girls blog in the Django 2 by example book. I ran into this error: error message This is the code in my urls.py: code in mysite/urls.py Here is the code in the blog/urls.py code in blog/urls.py I did add this 'blog.apps.BlogConfig' to settings.py I followed carefully the instructions but somehow couldn't fix the problem. Can you please help me? Thanks a ton -
How to give a parent name in serializers?
I have three serializers as below: class MalbSerializer(serializers.ModelSerializer): class Meta: model = malb fields = ('zoning', 'zoningdesc', ) class MasrSerializer(serializers.ModelSerializer): class Meta: model = masr fields = ('solddate', 'soldprice', ) class MataSerializer(serializers.ModelSerializer): class Meta: model = mata fields = ('assessyear', 'landvalue', ) The views is as below: malb_serializer = MalbSerializer(malb.objects.filter(maid=maid), many=True) masr_serializer = MasrSerializer(masr.objects.filter(maid=maid), many=True) mata_serializer = MataSerializer(mata.objects.filter(maid=maid), many=True) reponse = malb_serializer.data + masr_serializer.data + mata_serializer.data return Response(reponse) as a result, the response is as below: [ { "zoning": null, "zoningdesc": null, }, { "solddate": null, "soldprice": null, }, { "assessyear": null, "landvalue": null, } ] I want to give each element a tag like as below: [ {"Land Building": { "zoning": null, "zoningdesc": null, }}, { "Sales Record":{ "solddate": null, "soldprice": null, }}, {"Tax Assessment":{ "assessyear": null, "landvalue": null, }} ] I have tried to use a nested serializer, but I don't have a model which includes all these three messages, which can I use to give them a json parent name base on my current code? Any help will be many appreciated. Thanks! -
How to override DurationField widget with three NumberInput for years, months and days?
The default widget for DurationField is a single input box. But I need three input boxes, one for years, other for months and the last for days, the three inputs need to be converted to days to be stored in a single DurationField. Is there a way to archieve this? -
Getting an error whenever i click on add to cart button
i created a cart app inside an ecommerce site am building but when i click on the add cart form that is rendered on my page, it doesn't come through. any help will be appreciated inside the cart app, i have the normal django files in it.(__init__.py, admin.py, apps.py, cart.py (added by me), models.py, tests.py, urls.py and views.py) Here are the content of files in my cart app that i filled with content. for cart.py: from cart.models import CartItems from catalog.models import Product from django.shortcuts import get_object_or_404 from django.http import HttpResponseRedirect import decimal import random CART_ID_SESSION_KEY = 'cart_id' # get the current user's cart id, sets new one if blank def _cart_id(request): if request.session.get(CART_ID_SESSION_KEY,'') == '': request.session[CART_ID_SESSION_KEY] = _generate_cart_id() return request.session[CART_ID_SESSION_KEY] def _generate_cart_id(): cart_id = '' characters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz1234567890!@#$%^&*()' cart_id_length = 50 for y in range(cart_id_length): cart_id += characters[random.randint(0, len(characters)-1)] return cart_id # return all items from the current user's cart def get_cart_items(request): return CartItems.objects.filter(cart_id=_cart_id(request)) # add an item to the cart def add_to_cart(request): postdata = request.POST.copy() # get product slug from post data, return blank if empty product_slug = postdata.get('self.slug','') # get quantity added, return 1 if empty quantity = postdata.get('quantity',1) # fetch the product or return a missing ... -
my qustion is about django gives an error while running the server
raise ImproperlyConfigured("The %s setting must be a list or a tuple. " % setting) django.core.exceptions.ImproperlyConfigured: The INSTALLED_APPS setting must be a list or a tuple. -
Dynamic Links and Data Updation in Django 1.11
I have tried a lot but was unable to find the desired solution. My Problem I have a list generated using a for loop in the HTML template. The code for this purpose is in my "dashboardhometemplate.html" file and is as : {%for item in device_alias_list%} <li> <a href=href="#" aria-expanded="false"><i class="fa fa-bar-chart"></i><span class="hide-menu">{{item}}</span></a> {% endfor %} My Database consist of two tables as : from django.db import models class device_parameter_data(models.Model): # id = models.AutoField(primary_key = True) Device_Id = models.CharField(max_length=10) Age = models.IntegerField(null = True) updated_time = models.DateTimeField(auto_now=True, null = False) def __str__(self): return self.Device_Id class device_user_data(models.Model): User_Name = models.CharField(max_length=150) Device_Id_Data = models.CharField(max_length=10, primary_key = True) Device_Alias_Data = models.CharField(max_length=20) def __str__(self): return self.User_Name + '(' + self.Device_Id + ')' My views.py is: from django.shortcuts import render,redirect from django.views import View from django.contrib.auth.forms import AuthenticationForm from django.contrib.auth import login from dashboardhome.models import device_parameter_data from dashboardhome.models import device_user_data class DashboardHomeViewClass(View): def get(self, request, *args, **kwargs): device_user_objects = device_user_data.objects.filter(User_Name = request.user.username) device_alias_list = [] device_id_list = [] for device in device_user_objects: device_alias_list.append(device.Device_Alias_Data) device_id_list.append(device.Device_Id_Data) context_logged = {'device_alias_list': device_alias_list} return render(request, "dashboardhometemplate.html", context_logged) Now what I want to do is: As soon as the user clicks on the list item then I want to pass the ... -
Binary image storage in Django models
I want to load an image using ImageField, convert it to binary or base64 and save in the database just the code. I want to save the binary / base64 in the database, not the image. I want to use "bytea" (PostgreSQL) I do not want to save the image or the directory in the bank. My teacher wants to use Binary Data Typing in this project. I need help, please. class Trap_Image(models.Model): date = models.DateField('publication date') trap = models.ForeignKey(Trap, on_delete=models.CASCADE) image = models.ImageField() # missing binary or base64 part def __str__(self): return self.id class Meta: verbose_name = 'Image' verbose_name_plural = 'Images' -
How to create more than one formset in one CreateView?
I have two models: class Recipe(Model): title = CharField(blank=True, max_length=255) slug = SlugField() user = ForeignKey(get_user_model(), on_delete=CASCADE) categories = TaggableManager() class Meta: ordering = ['id'] def save(self, *args, **kwargs): self.slug = slugify(self.title, allow_unicode=True) return super(Recipe, self).save(*args, **kwargs) def get_absolute_url(self): return reverse("recipes:detail", kwargs={"pk": self.pk}) class RecipeStep(Model): recipe = ForeignKey(Recipe, on_delete=CASCADE, related_name="steps") ingredients = ManyToManyField(Ingredient) title = CharField(blank=True, max_length=255) slug = SlugField() def save(self, *args, **kwargs): self.slug = slugify(self.title, allow_unicode=True) return super(RecipeStep, self).save(*args, **kwargs) And I needed to make it so that when creating a Recipe model it was possible to create a RecipeStep model: For this I did 2 ModelForm and inlineformset: class RecipeForm(forms.ModelForm): class Meta: model = Recipe fields = ['title'] class RecipeStepForm(forms.ModelForm): class Meta: model = RecipeStep fields = ['title'] RecipeInlineForm = inlineformset_factory( Recipe, RecipeStep, form=RecipeStepForm, extra=1, can_delete=False, can_order=False ) I create a new Recipe with CreateView: class RecipeCreateView(LoginRequiredMixin, CreateView): model = Recipe form_class = RecipeForm def form_valid(self, form): form.instance.user = self.request.user context = self.get_context_data() inlines = context['inlines'] if inlines.is_valid() and form.is_valid(): self.object = form.save() for inline in inlines: inline.instance.recipe = self.object inline.save() return super(RecipeCreateView, self).form_valid(form) else: return self.render_to_response(self.get_context_data(form=form)) def form_invalid(self, form): return self.render_to_response(self.get_context_data(form=form)) def get_context_data(self, **kwargs): context = super(RecipeCreateView, self).get_context_data(**kwargs) if self.request.POST: context['form'] = RecipeForm(self.request.POST) context['inlines'] = RecipeInlineForm(self.request.POST) ... -
Trouble deploying Django app with gunicorn and nginx
I started this process trying to deploy with uwsgi, but ran into problems and so after reading from some sources that gunicorn would be the better way to go, I tried with that. Hopefully that didn't complicate things. I have all the preliminaries out of the way. I have Django app built, virtualenv installed, gunicorn installed, nginx installed. When I run command - gunicorn Hellfish.wsgi (Hellfish is project name) there is no response at first from the terminal (I guess that is normal processing speed?), but eventually I get this output: --- Logging error --- Traceback (most recent call last): File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/logging/__init__.py", line 996, in emit self.flush() File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/logging/__init__.py", line 976, in flush self.stream.flush() RuntimeError: reentrant call inside <_io.BufferedWriter name='/Users/whodini/desktop/who/web/Hellfish/logs/gunicorn-error.log'> Call stack: File "/Users/whodini/Desktop/who/Web/Hellfish/env/bin/gunicorn", line 11, in <module> sys.exit(run()) File "/Users/whodini/Desktop/who/Web/Hellfish/env/lib/python3.6/site-packages/gunicorn/app/wsgiapp.py", line 61, in run WSGIApplication("%(prog)s [OPTIONS] [APP_MODULE]").run() File "/Users/whodini/Desktop/who/Web/Hellfish/env/lib/python3.6/site-packages/gunicorn/app/base.py", line 223, in run super(Application, self).run() File "/Users/whodini/Desktop/who/Web/Hellfish/env/lib/python3.6/site-packages/gunicorn/app/base.py", line 72, in run Arbiter(self).run() File "/Users/whodini/Desktop/who/Web/Hellfish/env/lib/python3.6/site-packages/gunicorn/arbiter.py", line 203, in run self.manage_workers() File "/Users/whodini/Desktop/who/Web/Hellfish/env/lib/python3.6/site-packages/gunicorn/arbiter.py", line 545, in manage_workers self.spawn_workers() File "/Users/whodini/Desktop/who/Web/Hellfish/env/lib/python3.6/site-packages/gunicorn/arbiter.py", line 616, in spawn_workers self.spawn_worker() File "/Users/whodini/Desktop/who/Web/Hellfish/env/lib/python3.6/site-packages/gunicorn/arbiter.py", line 583, in spawn_worker worker.init_process() File "/Users/whodini/Desktop/who/Web/Hellfish/env/lib/python3.6/site-packages/gunicorn/workers/base.py", line 134, in init_process self.run() File "/Users/whodini/Desktop/who/Web/Hellfish/env/lib/python3.6/site-packages/gunicorn/workers/sync.py", line 124, in run self.run_for_one(timeout) File "/Users/whodini/Desktop/who/Web/Hellfish/env/lib/python3.6/site-packages/gunicorn/workers/sync.py", line 83, in ... -
How to remove image url in DJANGO admin ImageField
[https://i.stack.imgur.com/SVoxO.png][1] [https://i.stack.imgur.com/fRvaP.png][2] I am new to programming and Django i am using generic views and I want to remove this current path tag from Django admin how to do it? -
Django CreateView filter foreign key in select field
I need some help with Django 2 and Python 3. I'm using a CreateView to add new reccords in my database, but I need to make a filter in "Aviso" form page to make the select field (field "turma") to show only "turmas" that the "representante" is the current user. This is my model: class Turma(models.Model): nome = models.CharField(max_length=120, blank=False, null=False, help_text='Obrigatório.') alunos = models.ManyToManyField(User, help_text='Obrigatório', related_name='alunos_matriculados') data_cadastro = models.DateField(auto_now_add=True) representante = models.ForeignKey(User, on_delete=models.PROTECT, blank=False, null=False) colegio = models.ForeignKey(Colegio, on_delete=models.PROTECT, blank=False, null=False, help_text='Obrigatório.') class Aviso(models.Model): data_final = models.DateField(auto_now=False, auto_now_add=False, blank=False, null=False, verbose_name="Data Final") comentarios = models.TextField(null=True, blank=True) ultima_modificacao = models.DateField(auto_now=True) data_post = models.DateField(auto_now_add=True) turma = models.ForeignKey(Turma, on_delete=models.PROTECT, null=False, blank=False) materia = models.ForeignKey(Materia, on_delete=models.PROTECT, null=False, blank=False) This is my view: class AvisoCreateView(LoginRequiredMixin, CreateView): #Cadastro de Aviso template_name = 'form.html' model = models.Aviso login_url = '/login/' success_url = reverse_lazy('visualizar_aviso') fields = [ 'turma', 'materia', 'tipo_aviso', 'comentarios', 'data_final' ] def get_context_data(self, **kwargs): context = super().get_context_data(**kwargs) context['titulo'] = 'Cadastrar aviso' context['input'] = 'Adicionar' return context Thank you.
