Django community: RSS
This page, updated regularly, aggregates Django Q&A from the Django community.
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Django REST Framework Error 500 when receive '&' (And Symbol)
I have been confusing with this bug, I give & symbol in json raw body and return Server Error 500. And then I removed it so it works very well. Is this code bug or Django bug ? The REST Server is not my own so I cannot show you the code. -
How to run a function in the background after my django website starts?
I have written an algorithm. And when I use python manage.py runserver, my website will run on the local server. Now I want to run my algorithm after python manage.py runserver. In other words, when I start the django website, I hope the algorithm will run in the background until it is completed. And I want to know if the algorithm is still running or the algorithm is complete. What should I do? Thanks. -
I'm writing a stock exchange for an online game. How do I ensure orders are executed in isolation, using Django and Postgres?
I'm writing an online game using Django, and I'm planning to use Postgres as the database engine. One of the features of the game is going to be a simulated stock exchange and commodity market. If User A says "I want to buy an apple for $50" and User B says "I want to sell an apple for $50", then those two orders should be matched with each other, causing User B to sell an apple to User A. However, I'm not sure how to ensure that order executions are isolated from each other and don't introduce inconsistencies. I haven't written any real code for this feature yet, but let's assume that the model classes look like this: class Account(models.Model): number_of_dollars = models.BigIntegerField(validators=[MinValueValidator(0)], default=0) number_of_apples = models.BigIntegerField(validators=[MinValueValidator(0)], default=0) class AppleOrder(models.Model): account = models.ForeignKey(Account, on_delete=models.CASCADE) price = models.IntegerField(validators=[MinValueValidator(0)], default=0) direction = models.IntegerField(choices=[(1, 'buy'), (2, 'sell')]) status = models.IntegerField(choices=[(1, 'open'), (2, 'canceled'), (3, 'filled')]) Certain web requests may result in the game searching for orders that match each other, and executing them. But how can I make sure that orders are executed correctly? Naively, I would want to do it like this: def execute_orders(buy_order, sell_order, price) # We assume that "buy_order" and … -
How do I update the django models on runtime?
I have a normal Django model. I want to give a certain user the ability to add custom fields. I want the model to update during runtime and the database migrations to apply and then the user can do regular CRUD operations. Example of a simple Model is class location(models.Model): AuotLocationID = models.CharField(max_length=200) LocationID = models.CharField(max_length=200) Name = models.CharField(max_length=200) The user should be able to add other model fields such as Postal Code, Population, etc. Also each instance of the model should be linked to each user. For example Bob may want to track certain fields for his location and John may want some other fields. Thank you for your help -
500 Error running Django, Apache2, PostGreSQL Ubuntu 18.04.3 LTS
Sorry if I seem lost, but I have very little experience deploying web applications and searching online isn't helping. As the title states, I am running Ubuntu, Apache2, PostgreSQL, and Django , -- and I repeatedly get error messages, most of which are either vague and/or have no clear solutions. Plus my ignorance on the specific interactions quicksands any attempt at finding a solution, so i will be very specific. Installations: - apache2 libapache2-mod-wsgi-py3 -- for python 3 - I can't remember if I installed django or if it automatically packaged with my PyCharm package. - PostgreSQL - works fine. The Application: - It is a cloud computing platform, so it needs to receive files, store files, and render files. - Works fine with Django's web server attached. - has static files and needs to write to a media folder settings.py: - DEBUG = True - WSGI_APPLICATION = 'example.wsgi.application' -DATABASES = 'default': 'ENGINE': 'django.db.backends.postgresql_psycopg2', 'NAME': 'example', 'USER': 'example', 'PASSWORD': 'example', 'HOST': 'localhost', 'PORT': '', 000-default.conf ServerName FireAnts.localhost ServerAlias www.FireAnts.localhost DocumentRoot /var/www/FireAnts Require all granted WSGIDaemonProcess FireAnts python-path=/var/www/FireAnts python-home=/var/www/FireAnts/venv WSGIProcessGroup FireAnts WSGIScriptAlias / /var/www/FireAnts/FireAnts/wsgi.py ERRORS, per the log - Currently, i'm getting "No module named 'django'". - Frequently i get "populate" … -
Is it possible to create a new row in models.py for a list of items in django?
I'm trying to create a todo app, and I want to have a CharField in my models.py for each todo item. Here's my code right now: class Profile(models.Model): user = models.OneToOneField(User, on_delete=models.CASCADE) todo = models.CharField(max_length=1000, default='') def __str__(self): return f'{self.user.username} Profile' I want to make it so a new row in the database is created for each new todo. For example, there would be a row for one task, and another row for another task. How would I go about this? Thanks in advance! -
Django comment reply system not clearing textarea and loading scripts
I'm creating a Django comment and reply system but I am facing an issue when I comment I need to refresh the page for the jquery functions in 'post_comment' to work it seems the functions to not work without refreshing the page, also after using the modal to submit a comment I need to refresh the page for the text area to clear else it remains the same. This is my post_detail view: @login_required def post_detail(request, guid_url): data = dict() post = get_object_or_404(Post, guid_url=guid_url) comments = Comment.objects.filter(post=post,reply=None) if request.method == 'POST': form = CommentForm(request.POST) if form.is_valid(): comment = form.save(False) reply_id = request.POST.get('comment_id') comment_qs = None if reply_id: comment_qs = Comment.objects.get(id=reply_id) comment.name = request.user comment.post = post comment.reply=comment_qs comment.save() else: data['is_valid'] = False else: form = CommentForm comment_count = post.comments.count() context = {'post':post, 'form':form, 'comments':comments, 'comment_count':comment_count, } if request.is_ajax(): data['comments'] = render_to_string('home/posts/post_comment.html',{'comments':comments,'comment_count':comment_count},request=request) return JsonResponse(data) return render(request,'home/posts/post_detail.html',context) my post_detail.html {% extends "home/homepage/base.html" %} {% load crispy_forms_tags %} {% load static %} {% block content %} <style> .modal-body { min-height: calc(100vh - 510px); overflow-y: auto; } .post-border-div { border: 1px solid; opacity: 0.5; } button, textarea { outline:none !important; box-shadow: none !important; -moz-box-shadow:none !important; -webkit-box-shadow:none !important; } button:hover { opacity: 0.6; } </style> … -
Include choices with no records in grouped queryset
I'm trying to make a query in django grouping by a field with choices. I wanna get all choices values, algo choices with no records in the database. My model: CHOICES = ( ('new', 'New'), ('in_process', 'In process'), ('finished', 'Finished') ) class Task(models.Model): ... status = models.CharField(max_length=10, choices=CHOICES) My current query is: qs = Task.objects\ .values('status')\ .annotate(total=models.Count('status')) At this moment, I only have finished task in db, but I wanna get all choices values, with zero if it doesn't have records. Any idea? -
Django model shows up twice in all queries
I have three models like so: class Profile(models.Model): id = ShortUUIDField(primary_key=True, unique=True) class Bounty(models.Model): id = ShortUUIDField(primary_key=True, unique=True) creator = models.ForeignKey('Profile', related_name="bounties", on_delete=models.PROTECT) class BountyCompletion(models.Model): id = ShortUUIDField(primary_key=True, unique=True) profile = models.ForeignKey(Profile, related_name="bounty_completions", on_delete=models.CASCADE) bounty = models.ForeignKey(Bounty, related_name="bounty_completions", on_delete=models.CASCADE) url = models.URLField() So the idea is to have Profiles and Bounties, and the Profiles can create a bounty, then Complete as many bounties as they want, however many times as they want, each time they provide a different url. The problem is when I have two or more BountyCompletions with the same profile and bounty, and then I call either Bounty.objects.all() or profile_instance.bounties.all(), that bounty shows up twice (same id, same everything but it appears twice). I've tried setting it up like this as well as making the BountyCompletion table a through table for a manytomany from Profile to Bounty, but both have the same result. -
how can i call OneToOneField values in admin using list_display=[]
my model class user_profile(models.Model): user = models.OneToOneField(User, on_delete=models.CASCADE) age = models.IntegerField() profile_created = models.DateTimeField(auto_now_add=True, auto_now=False) timestamp = models.DateTimeField(auto_now=True, auto_now_add=False) admin.py class UserProfileAdmin(admin.ModelAdmin): list_display = ['user','user.username','profile_created', 'timestamp'] admin.site.register(user_profile, UserProfileAdmin) it show the error: ERRORS: : (admin.E108) The value of 'list_display[1]' refers to 'user.username', which is not a call able, an attribute of 'UserProfileAdmin', or an attribute or method on 'testapp.user_profile'. how can i fetch another table values in Admin.py. -
how to server dynamic files in django?
I know there are many answer already, but unfortunately I failed to find a solution on them. Basically I am trying to serve image files stored at server|/srv/post/users/folder/PIMAGES/ACTIVE/image.jpg to client, but with the configuration I have in my settings.py file, I am getting an http 404 file not found error. my settings.py file: STATIC_URL = '/static/' MEDIA_ROOT = '/srv/post/' MEDIA_URL = '/post/' and then if I refer to http://127.0.0.1:8000/post/users/folder/PIMAGES/ACTIVE/image.jpg I just get 404 page not found. -
How to create chained select related in django admin list_filters
I use the great django suit as django admin dashboard. Otherwise, list filters will not be as select lists. Those select lists are strengthened with django's built-in RelatedOnlyFieldListFilter class which limits the select list elements. However, I couldn't achieve to make them chained selects, by which I mean that if one select has child selects, those children would show their list depending to parent. Continents (select list) --> Europe is selected Countries (select list) --> would show the countries within Europe and Italy is selected. Cities (select list) --> only Italian cities would show up, Rome is selected And as being the above selects are admin panel list filters, only the records related with Rome should be listed in admin edit list page. Possible? Did I tried any thing? Yes many things and I couldn't achieve so I am led to create an alternative edit page with vue. However, it has many other problems. -
When to use PyMongo vs MongoEngine in Django?
I'm working on a web app Project using Django with Mongo. But I'm Confused which one to approach. Should I use Pymongo or MongoEngine in Django. What is the purpose of both and when to use Pymongo & MongoEngine? -
Dealing GenericRelation and GenricForeignKey inside migrations
I have models with GenricForeigKey and GenericRelation fields. class Datasheet(models.Model): package1 = GenericRelation('PackageInstance') ... class PackageInstance(models.Model): content_object = GenericForeignKey() object_id = models.PositiveIntegerField(null=True) content_type = models.ForeignKey(ContentType, null=True, on_delete=models.CASCADE) .... I am migrating from another models, inside my migration I want to create new instance. for ds in Datasheet.objects.all(): pi = PackageInstance.objects.create(content_object=ds) However this fails TypeError: DesignInstance() got an unexpected keyword argument 'content_object' Additionally, ds.package1.all() will also fail. AttributeError: 'Datasheet' object has no attribute 'package1' How do I solve this? -
Django redirecting to detail page after creating post (FBV)
I am making simple blog right now. I am trying to redirect page after creating post. models.py from django.db import models from django.db.models.signals import post_delete from django.conf import settings from django.dispatch import receiver class FreeBoardPost(models.Model): title = models.CharField(max_length=100, null=False, blank=False) content = models.TextField(max_length=5000, null=False, blank=False) date = models.DateTimeField(auto_now_add=True) author = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE) def __str__(self): return self.title @receiver(post_delete, sender=FreeBoardPost) def freeboard_image_delete(sender, instance, *args, **kwargs): instance.image.delete(False) urls.py from django.urls import path from .views import FreeBoardListView, FreeBoardDetailView, create_freeboard_view urlpatterns = [ path("", FreeBoardListView.as_view(), name="freeboard"), path("<int:pk>/", FreeBoardDetailView.as_view(), name="freeboard_detail"), path("create/", create_freeboard_view, name="freeboard_create"), ] views.py from django.shortcuts import render, redirect, get_object_or_404 from django.views.generic import ListView, DetailView from .models import FreeBoardPost from .forms import CreateFreeBoardPost from users.models import CustomUser class FreeBoardListView(ListView): model = FreeBoardPost template_name = "bbs/freeboard/free_board.html" context_object_name = "free_board_list" def get_queryset(self): return FreeBoardPost.objects.order_by("-id") class FreeBoardDetailView(DetailView): model = FreeBoardPost template_name = "bbs/freeboard/free_board_detail.html" def create_freeboard_view(request, pk): post = get_object_or_404(FreeBoardPost, pk=pk) context = {} user = request.user if not user.is_authenticated: return redirect("login") form = CreateFreeBoardPost(request.POST or None) if form.is_valid(): obj = form.save(commit=False) author = CustomUser.object.filter(email=user.email).first() obj.author = author obj.save() return redirect("freeboard_detail", pk=post.pk) context["form"] = form return render(request, "bbs/freeboard/free_board_create.html", context) The views.py code gave me an error create_freeboard_view() missing 1 required positional argument: 'pk'. Is there way I can redirect … -
How can I see data from an already made mysql database on Django?
I'm new to Django and I am trying to use a mysql database created and filled with data by someone else I created a model with the same name as the table I want to get data from, my models is as follows class Study(models.Model): study_name = models.TextField(default='Unknown') description = models.TextField(default='Unknown') language = models.TextField(default='Unknown') number_of_years = models.IntegerField(default='0') database connected but when I go to admin I don't see the data there Please help me with this -
function detail view in django
For almost 5h I can't make detail view. My app name -movies My views: " def actor_view(request): actor_list = Actor.objects.all() context = {'actor_list': actor_list} return render(request,'movies/actor.html',context) def actor_detail_view(request,id): actorrr=get_object_or_404(Actor,id=id) context={ 'actorrr':actorrr, } return render(request,"movies/actor_detail_view.html",context) My model class Actor(models.Model): name = models.CharField(max_length=50) date_of_birth = models.DateField() age=models.IntegerField( null=True) net_worth = models.TextField(max_length=140, null=True) picture=models.URLField(default = '') children =models.TextField(max_length=140, null=True) marital_status=models.TextField(max_length=140, null=True) My actor html: {% load static %} {% block mainbody %} {% for actor in actor_list %} <!DOCTYPE html> <html> <head> <title>List of actors we have</title> <link rel="stylesheet" href="{% static 'css/style_actor.css' %}"> </head> <body> <div class="card" > <div class="card-image"> <img src="{{ actor.picture }}" alt="No poster in datebase" width="289" height="345"> </div> <div class="card-text"> <h2> <a href="/movies/actor_detail/{{actor.id }}">{{ actor.name }}</a> </h2> <p>{{movie.pilot}}</p> </div> <div class="card-imdb-score"> <p >Age: {{ actor.age }} </p> </div> </div> </body> </html> {% endfor %} {% endblock %} My actor_detail html <h6>TEST</h6> So I have no idea how to make urls and what to place in actor.html in href url.I've made many tutorials and still couldn't do it. -
I am developing a geolocation django application but getting error in postgis. please tell me what i am doing wrong
Currently, I am trying to build an application with Django geolocation using PostGIS and PostgreSQL but getting following error. I have inserted all libraries required but whenever I try to migrate the models i get error No such file or directory django.db.utils.OperationalError: could not open extension control file "C:/Program Files/PostgreSQL/12/share/extension/postgis.control": No such file or directory My settings.py file looks something like this """ Django settings for geodjango project. Generated by 'django-admin startproject' using Django 2.2.4. For more information on this file, see https://docs.djangoproject.com/en/2.2/topics/settings/ For the full list of settings and their values, see https://docs.djangoproject.com/en/2.2/ref/settings/ """ import os if os.name == 'nt': import platform OSGEO4W = r"C:\OSGeo4W" if '64' in platform.architecture()[0]: OSGEO4W += "64" assert os.path.isdir(OSGEO4W), "Directory does not exist: " + OSGEO4W os.environ['OSGEO4W_ROOT'] = OSGEO4W os.environ['GDAL_DATA'] = OSGEO4W + r"\share\gdal" os.environ['PROJ_LIB'] = OSGEO4W + r"\share\proj" os.environ['PATH'] = OSGEO4W + r"\bin;" + os.environ['PATH'] # Build paths inside the project like this: os.path.join(BASE_DIR, ...) 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/2.2/howto/deployment/checklist/ # SECURITY WARNING: keep the secret key used in production secret! SECRET_KEY = ')l@*3+2b@s()dvuyhjzgb*5p(x^(qp(!-ci(doykaso*=7_z-%' # SECURITY WARNING: don't run with debug turned on in production! DEBUG = True ALLOWED_HOSTS = [] # Application definition … -
How to import a django rest framework api in a pyspark udf executor?
I have a project where i'm integrating django rest framework (drf) and apache spark, so I have some endpoints and I need to execute some jobs with spark by using udf. I have the below structure of the project: core/ udf/ ├── pyspark_udf.py ├── (and the rest of the files of a django app) api/ ├── api.py ├── urls.py ├── (and the rest of the files of a django app) udf.zip So according with that structure: First, in api.py file i have the endpoint where I need to execute the job. Second, inside the pyspark_udf.py, I call to an endpoint that is in the api.py file, I do some logic there and return the response. Then, again in the api.py file, I use the value returned to create a new column in a pyspark dataframe. Finally, I return the json data response in the drf endpoint. I achieved that behavior but using requests in the pyspark_udf.py function, which I considerer that is not elegant or best practice, working with an api that is in my own project, instead of do a simple call to the class of the drf endpoint. I created the minimum code below to reproduce the error … -
How to create a django formset or form add/edit page in order to edit several records
For one of my open source projects, I need to create ONE add/edit page in order to make possible to edit several records with one save. The repo is an IMDB clone formed for learning purpose. A user can add her/his favorite genres in her/his profile. Then an edit page is formed to show the list of those favored genres and the movies within that genre. (A for loop here) User can add notes, watch list options and so on to those movies. (NOT a FORMSET) However, the code doesn't work as expected. The page cannot be saved and only the first checkbox of the list can be changed. There is no error. NOTE: You can install repo with dummy data. (https://github.com/pydatageek/imdb-clone) Then after logging in, select your favorite genres. (http://localhost:8000/users/profile/) Then (I wish it can be solved here) you can see the movies with your selected genres. Add notes, to watch list... (http://localhost:8080/users/profile/movies2/) # users/templates/user-movies-with_loop.html {% extends 'base.html' %}{% load crispy_forms_tags %} <!-- Title --> {% block htitle %}Your movies from favorite genres{% endblock %} {% block title %}Your movies from favorite genres{% endblock %} {% block content %} <div class="card card-signin"> {% include 'users/profile-menu.html' %} <h3 class="card-title text-center … -
Django One-to-one structure
I am trying to create a One-to-one relationship between Table1 and Table2, I have migrated these successfully and it looks alright. I have populated Table1 with data, but when I try to populate Table2 with some data I receive an error message: Field 'table1_id' doesn't have a default value. My understanding was that the table_id that is being created for Table2 by using OneToOne should be self-populated. For every row in Table1 there will be a row in Table2 with some additional data, I would like to print these out in my template. I assume something is wrong in my structure. Any feedback would be highly appreciated! My models.py from django.db import models class Table1(models.Model): created = models.DateTimeField(default=None) published = models.CharField(max_length=50, default=None) code = models.CharField(max_length=25, null=True, unique=True) class Meta: db_table = 'Table1' unique_together = (("created", "published"),) def __str__(self): return self.created class Table2(models.Model): table1 = models.OneToOneField(Table1, on_delete=models.CASCADE, primary_key=True, default=None) code = models.CharField(max_length=50, default=None, null=True) url = models.CharField(max_length=100, default=None, null=True) more = models.CharField(max_length=100, default=None, null=True) class Meta: managed = True def __str__(self): return self.code -
Storing factory-boy RelatedFactory Object on Parent Factory
I have two Django models (Customer and CustomerAddress) that both contain ForeignKeys to each other. I am using factory-boy to manage creation of these models, and cannot save a child factory instance onto the parent factory (using relationships defined using the RelatedFactory class). My two models: class ExampleCustomerAddress(models.Model): # Every customer mailing address is assigned to a single Customer, # though Customers may have multiple addresses. customer = models.ForeignKey('ExampleCustomer', on_delete=models.CASCADE) class ExampleCustomer(models.Model): # Each customer has a single (optional) default billing address: default_billto = models.ForeignKey( 'ExampleCustomerAddress', on_delete=models.SET_NULL, blank=True, null=True, related_name='+') I have two factories, one for each model: class ExampleCustomerAddressFactory(factory.django.DjangoModelFactory): class Meta: model = ExampleCustomerAddress customer = factory.SubFactory( 'ExampleCustomerFactory', default_billto=None) # Set to None to prevent recursive address creation. class ExampleCustomerFactory(factory.django.DjangoModelFactory): class Meta: model = ExampleCustomer default_billto = factory.RelatedFactory(ExampleCustomerAddressFactory, 'customer') When creating a ExampleCustomerFactory, default_billto is None, even though a ExampleCustomerAddress has been created: In [14]: ec = ExampleCustomerFactory.build() In [15]: ec.default_billto is None Out[15]: True (When using create(), a new ExampleCustomerAddress exists in the database. I am using build() here to simplify the example). Creating an ExampleCustomerAddress works as expected, with the Customer being automatically created: In [22]: eca = ExampleCustomerAddressFactory.build() In [23]: eca.customer Out[23]: <ExampleCustomer: ExampleCustomer object> In … -
Run RQ jobs from other machine
I have a django app which pushes jobs on a Redis Queue by means of django-rq. I want to deploy the app on some host like Heroku. Can I pull and process those jobs from another machine, say a raspberry pi from home? -
''Error in formatting: AttributeError: 'UUID' object has no attribute 'int'
PLEASE SUGGEST HOW TO SOLVE THIS !!! Details : python website from github , using in local host (ubuntu) , database sqlite3 Getting error AttributeError: 'UUID' object has no attribute 'int' in line: raise ValueError('badly formed hexadecimal UUID string') Variable Value connection expression Col(accounts_customuser, accounts.CustomUser.id) self value '1' -
Submit button does not work after bootstrap styling in DJANGO
After I apply mdbootstrap, submit button function is broken. Nothing happens when i clicked. my view.py code: def scanDetail(request,scan_pk): context = { bla bla bla } if request.method == 'GET': return render(request, 'test/scanDetail.html',context) else: selected_values = request.POST.getlist('falsePositive') **if request.POST.get("save"):** for scan in scanResults: if request.POST.get("a"+str(scan.id)) == "clicked": scan.falsePositive = True else: scan.falsePositive = False scan.save() return redirect('scAppv2:currentSc') here is my template: {% for scan in xxxx %} <form method="POST"> {% csrf_token %} <tr> <td> {% if scan.falsePositive == True %} <input type="checkbox" name="c{{ scan.id }}" value="clicked" checked /> {% else %} <input type="checkbox" name="c{{ scan.id }}" value="clicked" /> {% endif %} </td> <td>{{ scan.a }}</td> <td>{{ scan.b }}</td> <td>{{ scan.c }}</td> <td>{{ scan.d }}</td> </tr> {% endfor %} </tbody> </table> <br> **<button type="submit" class="btn btn-default" name= "save" value="save" />SAVE</button>** </form> If i delete below code, everything goes to nice, and submit works. But i did not understand rootcause. <script type="text/javascript"> $(document).ready(function () { $('#scanDetailMainTable').DataTable({ "paging": false // false to disable pagination (or any other option) }); $('.dataTables_length').addClass('bs-select'); }); </script> Please help me anyone? Thanks.
