Django community: RSS
This page, updated regularly, aggregates Django Q&A from the Django community.
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How to make a large variable global in Django?
I am working on a simple web application that utilizes a moderately large NLP model, which is the same for all users and ideally I hope to re-load the model from a new model file generated daily. Is there a way to make the variable storing this model to be global? Loading it from a file every time a user uses it would be quite slow and it seems to be too large (~1GB) to be put into sessions. Thank you! -
What gets deleted when I delete a model in django (postgress)?
Lets say I have a model Books: class Books(models.Model): name = models.Charfield() author = models.Charfield() and later I set up another model called BookReviews which links to Books: class BookReviews(models.Model): book = models.ForeignKey(Books) content = models.TextField() But I messed up and I want to delete model BookReviews completely. When I run python manage.py migrate I get a warning message: Any objects related to these content types by a foreign key will also be deleted. Are you sure you want to delete these content types? Does that mean any entries linked to in Books will also be deleted even if those entries existed before BookReviews? -
Django Model ManyToMany Reverse Filter
Here's excerpts from (something analogous to) my models: class Person(models.Model): name = models.CharField(max_length=20) relationships = models.ManyToManyField('self', through='Relationship', symmetrical=False, related_name='related_to', ) def __str__(self): return self.name class Relationship(models.Model): from_person = models.ForeignKey(Person, related_name='from_people', on_delete=models.CASCADE, ) to_person = models.ForeignKey(Person, related_name='to_people', on_delete=models.CASCADE, ) status = models.CharField(max_length=20) def __str__(self): return "{} is {} {}".format( self.from_person.name, self.status, self.to_person.name) Here's the contents of my database: >>> Person.objects.all() <QuerySet [<Person: A>, <Person: B>, <Person: C>]> >>> Relationship.objects.all() <QuerySet [<Relationship: B is Following C>]> If I want to see who a given person is following, I can build a new method into the Person class: def get_following(self): return self.relationships.filter( to_people__status='Following', to_people__from_person=self) This works: >>> p2.get_following() <QuerySet [<Person: C>]> I want to do the REVERSE of this. Instead of asking "Who does this person follow?", I want to ask "Who follows this person?". I can do that like this (although it returns Relationship objects, not Person objects): >>> Relationship.objects.filter(to_person=p3, status='Following') <QuerySet [<Relationship: B is Following to C>]> My attempt is this (which returns an empty QuerySet): def get_following(self): return self.relationships.filter( from_people__status='Following', from_people__to_person=self) Your help is appreciated! -
what version to learn for django
I am beginning Django, I am stuck in what version to learn, version 2.0 does not use regular expressions but a lot of the books out there teach version 1.8 which was the old LTS. Any advice would be appreciated. Thanks -
Excel files not showing on Heroku web app
I have a django backed website on Heroku and every time I try to view/download the upload excel files after uploading them on the Heroku website I get this error: Not Found: The requested URL /excel_files/<file> was not found on this server. Here is my views.py: from django.shortcuts import render from django.http import HttpResponseRedirect from django.core.urlresolvers import reverse from .forms import UploadForm from django.conf import settings import os import openpyxl, re def index(request): """The home page which generates the donor list html page""" if request.method != 'POST': form = UploadForm() else: form = UploadForm(request.POST or None, request.FILES or None) if form.is_valid(): form.save() file = request.FILES['fileobj'].name file_corrected = file.replace(" ", "_") path = os.path.join(settings.MEDIA_ROOT, file_corrected) wb = openpyxl.load_workbook(path) sheet = wb.get_sheet_by_name('Sheet1') text_file = open('upload/templates/upload/donor_list.html', 'w') html1 = "{% extends 'upload/base.html' %}" + "\n" + "{% block header %}" + "\n" + " <h1>Donor List</h1>" + "\n" + "{% endblock header %}" + "\n" + "{% block content %}" + "\n" html2 = "{% endblock content %}" text_file.write(html1) for rowNum in range(1, sheet.max_row + 1): firstName = str(sheet.cell(row=rowNum, column=1).value) if firstName == "None": firstName = "\n" lastName = str(sheet.cell(row=rowNum, column=2).value) addNum = re.compile(r'\d(\d)*') addressNumber1 = addNum.search(str(sheet.cell(row=rowNum, column=3).value)) if addressNumber1 is None: addressNumber … -
why the data injected in template is only available if user is login? want all public
I am working on a portfolio web, with an about page, the models are created on the DB, and the template tagging is working, but just if user is authenticated in the admin page, I´ve extended the user model to a userprofile one, to show the portfolio data stored on the DB, obviously I want this to be public for everyone but I cant get it; also I want to manage all the models related to the app just with the superuser, as I have no need to create more users because is a simple portfolio for one single user. CODE: from django.db import models from django.contrib.auth.models import User from django.db.models.signals import post_save class UserProfile(models.Model): user = models.OneToOneField(User) bio = models.TextField(max_length=1000, blank=True) location = models.CharField(max_length=30, blank=True) avatar = models.ImageField(upload_to='profile/', null=True, blank=True) uploaded_at = models.DateTimeField(auto_now_add=True) def __str__(self): return "{} Portfolio ".format(self.user) def create_user_profile(sender, instance, created, **kwargs): """Create the UserProfile when a new User is saved""" if created: profile = UserProfile() profile.user = instance profile.save() post_save.connect(create_user_profile, sender=User) # ######################################################################################## from coltapp.models import Post, Comment, UserProfile from django.views.generic import (TemplateView, ListView, DetailView, CreateView, UpdateView, DeleteView) class AboutView(ListView): model = UserProfile template_name = 'coltapp/about.html' select_related = ('userprofile') # ######################################################################################## from coltapp import views from … -
display data from a text file using django
I have a text file with lot of columns, these columns are separated by /t (tab). I want to write a view that display the first ,the second and the third column into a table. This is my view def displayfile(request): file = open("mytestapp/LinkBooster_20171002.txt","r") #alorithme of dispaly i don't know how context = { 'first_column' : src, 'first_column' : dst, 'first_column' : title, } return render(request,'myapp/display.html',context ) so in this view i want to get the colomnus -
How to modify field/TextField size in Django admin panel?
I am trying to update my inline class to modify the size of the character and text fields. This code formfield_overrides works fine in non inline classes, but it does not seem to do anything within the inline class. Am I approaching this the wrong way? See below for the code: class MyModelInLine(admin.TabularInline): formfield_overrides = { models.CharField: {'widget': TextInput(attrs={'size': '20'})}, models.TextField: {'widget': Textarea(attrs={'rows': 4, 'cols': 80})}, } model = custom_models.MyModel extra = 0 -
Django ORM: get queryset of one field type
I have a model ProblemVote which contains user (ForeignKey), problem (ForeignKey) and status field. I need all the problems (which has been voted) with status 'AC' and 'R'. I am able to fetch all the required problems in a Python list. However, i want to know if there is a better way using queryset methods. Part of my code: all_votes = ProblemVote.objects.filter( user=user).select_related("problem").filter(problem__stage='PV') all_votes_problems = [vote.problem for vote in all_votes] accepted_problems = [vote.problem for vote in all_votes if vote.status == 'AC'] rejected_problems = [vote.problem for vote in all_votes if vote.status == 'R'] Getting the problem as a queryset will help me in finding the count as queryset.count() and in finding queryset differences like queryset.difference(another_queryset). -
Returning child properties in JSON from Django Models
I have a database model setup in Django to track portfolios and am trying to develop a API to return a portfolio along with each coin in it, and each transaction associated with the coin. However using the api i only see the name field of my model being returned. Some code for clarification: model.py: class Portfolio(models.Model): name = models.CharField(max_length=250) @property def coins(self): return Coin.objects.filter(portfolio=self) def transactions(self): return Transaction.objects.filter(portfolio=self) def __str__(self): return self.name class Coin(models.Model): portfolio = models.ForeignKey(Portfolio, on_delete=models.PROTECT) name = models.CharField(max_length=100) symbol = models.CharField(max_length=5) price = models.DecimalField(max_digits=20, decimal_places=9) info = models.TextField() website = models.TextField() rank = models.IntegerField() def __str__(self): return self.name + " - " + self.symbol class Transaction(models.Model): portfolio = models.ForeignKey(Portfolio, on_delete=models.CASCADE) coin = models.ForeignKey(Coin, on_delete=models.PROTECT) purchaseDate = models.DateTimeField() soldDate = models.DateTimeField(default=None, null=True, blank=True) amount = models.DecimalField(max_digits=20, decimal_places=3) price = models.DecimalField(max_digits=20, decimal_places=9) def __str__(self): return self.coin.name + " - " + str(self.amount) + " At $" + str(self.price) My json serializer: class PortfolioSerializer(serializers.ModelSerializer): class Meta: model = Portfolio fields = '__all__' How data comes back: HTTP 200 OK Allow: GET, POST, HEAD, OPTIONS Content-Type: application/json Vary: Accept [ { "id": 3, "name": "Binance" } ] What I want is in the data set, under binance it should show … -
What is the preferred way to avoid duplication in validation in Django forms / serializers?
Where should the validation logic live so that it can be shared? What provides validation logic the easiest, least friction handling of relations in django models (model relationships, many-to-many and querysets) This is a related SO question, but the answer doesn't go into any detail and is only for the most basic use cases: How to avoid code duplication in Django Forms and Django Rest Framework Serializers? -
No MyUser matches the given query
I am having an error No MyUser matches the given query, and I am not sure why there is no a match since the URL is properly set. In my app I have two kind of users: Employees and candidates that are both part of the model MyUser and are differentiated by a boolean is_candidate or is_employee. My issue is when creating the user detail view. I started with the EmployeeDetailView : class EmployeeDetailView(LoginRequiredMixin, generic.DetailView): #import pdb; pdb.set_trace() model = MyUser template_name = 'employee_details.html' def get_object(self, queryset=None): return get_object_or_404(MyUser, pk=self.kwargs['pk2'], members__project=self.kwargs['pk1']) def get_context_data(self, **kwargs): context = super(EmployeeDetailView, self).get_context_data(**kwargs) employee_name = MyUser.objects.get(id=self.kwargs['pk2']) team_list = Project.objects.get(id=self.kwargs['pk1']).team_id.members.all() team_list_pop = Project.objects.get(id=self.kwargs['pk1']).team_id.members.all().exclude(id=self.kwargs['pk2']) context={ 'employee_name' : employee_name, 'team_list' : team_list, 'team_list_pop' : team_list_pop, } return context on URL : url(r'^project/(?P<pk1>[0-9]+)/(?P<pk2>[0-9]+)/$',views.EmployeeDetailView.as_view(), name='EmployeDetails'), That work properly and I am able to access my user detail So I wanted to do the same for CandidateDetailView with the code : class CandidateDetailView(LoginRequiredMixin, generic.DetailView): #import pdb; pdb.set_trace() model = MyUser template_name = 'employee_details.html' def get_object(self, queryset=None): print(self.kwargs['pk2']) return get_object_or_404(MyUser, pk=self.kwargs['pk2'], applicant__project=self.kwargs['pk1']) def get_context_data(self, **kwargs): context = super(CandidateDetailView, self).get_context_data(**kwargs) context={ } return context On URL : url(r'^project/(?P<pk1>[0-9]+)/(?P<pk2>[0-9]+)/$',views.CandidateDetailView.as_view(), name='CandidateDetails'), But this time I get the error that there is no matching Raised by: … -
Easy Django REST Framework Websocket Usage
I have a an application that uses Angular for the frontend and communicates with an API running Django RF. Now, let me try and outline what I'm trying to achieve in hopes of finding an easy solution. When a user runs a report, a worker version of the API generates the report to prevent the main API from bogging down. The report runs for a couple seconds/minutes. The user refreshes the page and voila, their report is there. What I'm trying to achieve is the elimination of the whole "user refreshes the page" portion of this process. My goal is to do this via websockets. I literally want something as simple as: WEB: "Hey API, I want this report. I'll wait." API: "Yo dog, you're reports done." WEB: "Cool, let me refresh my report list. Thanks bud." Now, we start to venture into an area I'm unfamiliar with. Websockets can do this, right? I just need to create a connection and wait for the all-clear to be sent by the worker. Now, here's where it gets hairy. I've spent the better part of the day going through libraries and just can't find what I need. The closest I've come is … -
django form ManyToMany Initial queryset value
This has oficially driven me crazy. I have a very basic form with 1 many to many field: models.py class ProtectionProfile(models.Model): Optional_SFR = models.ManyToManyField(SFR, related_name='Optional') Then my forms.py class OptForm(forms.Form): selecopt_sfr = forms.ModelMultipleChoiceField(queryset=MYProtectionProfile.Optional_SFR.all()) During my page render I get a number of protectionprofiles for a given user. for each protectionprofile I need to generate a form with those various Optional_SFR field. So how can I pass the relevant ProtectionProfile to the form for the correct query set? I feel like this should be really easy but I can't find it any where! Any help is greatly appreciated. -
adding a custom method to Meta class in django
I have an AbstractBase model class that gets inherited by several models in their respective apps. I want the user to be able to set a name that will be used in the verbose_name field in the Meta class. If a user provides a name in one of the fields in the AbstractBase model, then that field will be used as the verbose name this is what I have tried so far class AbstractBase(models.Model): ...... custom_name = models.CharField(blank=True) class Meta(object): abstract = True def update_verbose_name(self, custom_name): if self.project_setting is not None: return verbose_name == self.custom_name when I run this it gives me TypeError: 'class Meta' got invalid attribute(s): update_verbose_name is there another way that I solve this? -
Struggling with trans in a input placeholder
Here is the HTML part <div class="col-md-4 col-sm-4"> <input type="text" class="form-control" placeholder={% trans "First Name" %} id="cf-fn" name="cf-fn" required=""> </div> Instead of getting 'First Name', I got just 'First'. Here is a photo How could I fix it? -
Django ORM - a model object from using .get or indexing a QuerySet
my_model = MyModel.objects.get(pk=5) So 'my_model' is not a queryset object, neither would it be if I indexed it from a queryset. Is there something special about a QuerySet other than it is a list of objects from the table(s)? Also I was wondering, I know that simply creating a QuerySet does not involve a database lookup, but what about getting just one object like in 'my_model'? -
Django docker error table not exist
I had a existing Django Rest project with an existing MySQL database (named libraries) which I wanted to Dockerize. My dockerfile: FROM python:2.7 ENV PYTHONUNBUFFERED 1 RUN mkdir /code WORKDIR /code COPY . /code/ RUN pip install -r requirements.txt My docker-compose: version: '3' services: db: image: mysql environment: MYSQL_ROOT_PASSWORD: root MYSQL_DATABASE: libraries MYSQL_USER: root MYSQL_PASSWORD: root web: build: . command: python manage.py runserver 0.0.0.0:8000 volumes: - .:/code ports: - "8000:8000" Steps: I ran: docker-compose build - build was successful I ran: docker-compose up - had to run this command twice and then I could access my API by hitting localhost:8000 However, whenever I hit any API endpoint I get an error Table "XYZ" does not exist. All the tables are already present. Why this happens? -
How to pull other serialized data from different Serializer classes?
I'm trying to pull the permissions data into my UserSerializer. I have a Many To Many relationship with User to Group with a through table called GroupUser. I'm able to pull the group_id and the group_name, but I can't seem to populate the data for permissions into my User Serializer. So far I've tried using permission = serializers.ReadOnlyField(source='group.permissions') but that doesn't work. Any suggestions? Here's my code: class GroupSerializer(serializers.ModelSerializer): users = GroupUserSerializer(source='groupuser_set', many=True) permissions = PermissionSerializer(source='permission_set', many=True) class Meta: model = Group fields = ('id', 'name', 'users', 'permissions', 'role', ) class GroupUserSerializer(serializers.ModelSerializer): id = serializers.ReadOnlyField(source='group.id') name = serializers.ReadOnlyField(source='group.name') class Meta: model = GroupUser fields = ( 'id', 'name', ) class UserSerializer(serializers.ModelSerializer): tests = TestSerializer(source='test_set', many=True) groups = GroupUserSerializer(source='groupuser_set', many=True) class Meta: model = User fields = ( 'id', 'username', 'groups', 'tests', ) I want my data to look like this: { "id": 1, "username": "user", "groups": [ { "id": 2, "name": "employee" "permission": "Access-Denied" } ], "tests": [] }, but I have it without "permissions" -
Dynamically updating db_table to use one model for several database tables
I thought I ran into a roadblock with Django that would require writing raw SQL to resolve instead of using Django's ORM. I asked about it on SO and was informed it is possible to create dynamic classes or to assign db_table dynamically to the model. The issue is that I have several dozen tables that are similar. They do all have about five fields that are in them all. The remaining hundred, or so columns, are unique. (Basically each table represents industry data and a year; even within the same industry the data can vary from year to year). I was informed that Django models are pretty "loose" in that you could only identify these common columns and the model doesn't care about the rest of the columns, so you could do a Table.objects.all() and get everything in the table. My concern was I was going to need to build several dozen mostly redundant models, and have to add new ones annually which is really inefficient. I was leaning towards writing the query in raw SQL so I could dynamically specify the table name until I was informed of these things. Came across these SO questions, but I am … -
Running two databases on heroku with django
I have two databases that my Django application needs access. One is a shared database owned by a separate app with the Django app only having read access. The second is entirely owned by the Django app. For local development I am ok but I'm not sure how to configure things so that Heroku uses the second database. Currently I have the shared database promoted to DATABASE_URL and the secondary database is at HEROKU_POSTGRESQL_BLUE_URL. In my settings I have: DATABASES = { 'default': { 'ENGINE': 'django.db.backends.postgresql', 'NAME': 'main_database_name', 'USER': 'username', 'PASSWORD': '', 'HOST': 'localhost', 'PORT': '5432', }, 'secondary': { 'ENGINE': 'django.db.backends.postgresql', 'NAME': 'secondary_database_name', 'USER': 'username', 'PASSWORD': '', 'HOST': 'localhost', 'PORT': '5432', } } Please ask any more questions if you need me to clarify. Thanks! -
How to get objct information from Ajax response in JSON
I'm working on a site that needs to parse an Ajax response which looks something like this: {"comments": "[{\"model\": \"modelhandler.comment\", \"pk\": 4, \"fields\": {\"user\": 2, \"description\": \"hello this is a comment but I don't know if it's working yet.......\", \"replyto\": null, \"uploaded\": \"2018-01-10T20:35:40.856Z\", \"updated\": \"2018-01-10T20:35:40.856Z\"}}]"} I tried getting data from this response like this: success: function (data) { var json = JSON.parse(JSON.stringify(data)); $.each(json, function(key,value) { alert(value.comments); }); } This however alerts me undefined Here the comments field has 1 comment in it but I might have more than 1. How would I go about retrieving data from a Json response like this? EDIT: I logged data object and I got this: Object comments : "[{"model": "modelhandler.comment", "pk": 4, "fields": {"user": 2, "description": "hello this is a comment but I din't know if it's working yet.......", "replyto": null, "uploaded": "2018-01-10T20:35:40.856Z", "updated": "2018-01-10T20:35:40.856Z"}}]" __proto__ : Object in Google Chrome using console.log() also the json is generated by a django view like this: def obtain_comments(request, *args, **kwargs): begin = int(request.GET['begin']) end = int(request.GET['end']) n_comments = end - begin all_split = Comment.objects.order_by('-uploaded')[:end] data = { 'comments': serializers.serialize('json',all_split), } return JsonResponse(data) -
Django - Filter GTE LTE for alphanumeric IDs
I am trying to serve up our APIs to allow filtering capabilities using LTE and GTE on our ID look ups. However, the IDs we have are alphanumeric like AB:12345, AB:98765 and so on. I am trying to do the following on the viewset using the Django-Filter: class MyFilter(django_filters.FilterSet): item_id = AllLookupsFilter() class Meta: model = MyModel fields = { 'item_id': ['lte', 'gte'] } But the issue is, if I query as: http://123.1.1.1:7000/my-entities/?item_id__gte=AB:1999 or even http://123.1.1.1:7000/my-entities/?item_id__lte=AB:100 it won't exactly return items with ID's greater than 1999 or less than 100 since the filter will take ID as a string and tries to filter by every character. Any idea how to achieve so I can filter on IDs so I get items exactly greater / less than the numeric ID (ignoring the initial characters) ? -
Backend not Found for Facebook
I cant seem to get it to work guys, after reading similar questions my issue is not due to not specifying key and secret nor is it because i forgot to add '-oauth2' after facebook. please help?? All i see on the browser is Backend not Found. Maybe it is just because my django or python versions are too new?? I use python 3.6 and django 2.0... here is my project's settings.py SECRET_KEY = '<my_secret_key>' # SECURITY WARNING: don't run with debug turned on in production! DEBUG = True # Application definition INSTALLED_APPS = [ 'django.contrib.admin', 'django.contrib.auth', 'django.contrib.contenttypes', 'django.contrib.sessions', 'django.contrib.messages', 'django.contrib.staticfiles', 'main_app', 'django_filters', 'cuentas', 'social_django', ] MIDDLEWARE = [ 'django.middleware.security.SecurityMiddleware', 'django.contrib.sessions.middleware.SessionMiddleware', 'django.middleware.common.CommonMiddleware', 'django.middleware.csrf.CsrfViewMiddleware', 'django.contrib.auth.middleware.AuthenticationMiddleware', 'django.contrib.messages.middleware.MessageMiddleware', 'django.middleware.clickjacking.XFrameOptionsMiddleware', 'social_django.middleware.SocialAuthExceptionMiddleware', ] 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', 'social_django.context_processors.backends', 'social_django.context_processors.login_redirect', ], }, }, ] # python social auth settings SOCIAL_AUTH_FACEBOOK_KEY = '<facebook_app_id>' SOCIAL_AUTH_FACEBOOK_SECRET = '<facebook_app_secret>' SOCIAL_AUTH_FACEBOOK_SCOPE = ['email'] SOCIAL_AUTH_FACEBOOK_API_VERSION = '2.11' AUTHENTICATION_BACKENDS = [ 'social_core.backends.facebook.FacebookAppOAuth2', 'social_core.backends.facebook.FacebookOAuth2', 'django.contrib.auth.backends.ModelBackend', ] SOCIAL_AUTH_URL_NAMESPACE = 'social' SOCIAL_AUTH_PIPELINE = ( 'social_core.pipeline.social_auth.social_details', 'social_core.pipeline.social_auth.social_uid', 'social_core.pipeline.social_auth.social_user', 'social_core.pipeline.user.get_username', 'social_core.pipeline.user.create_user', 'social_core.pipeline.social_auth.associate_user', 'social_core.pipeline.social_auth.load_extra_data', 'social_core.pipeline.user.user_details', 'social_core.pipeline.social_auth.associate_by_email', ) -
PK2 as a context for a User Detail View
In my app I have two kind of users, Employees and candidates that are both part of MyUser model, with different attribute is_candidate, is_employee (True, False) My view EmployeeDetailView ( I need to change the name) is supposed to serve both, and while for employee users I am ok, for candidate user I am having an issue acceding to the User detail view because of pk2 that is not found, the PK1 is found. I In general I am having trouble to understand how to deal with multiple key arguments like Pk1 and pk2 I do not know how to define PK2 in my context my model is : class Project(models.Model): name = models.CharField(max_length=250) team_id = models.ForeignKey(Team, blank=True, null=True) project_hr_admin = models.ForeignKey('registration.MyUser', blank=True, null=True) candidat_answers = models.ManyToManyField('survey.response') applicant = models.ManyToManyField(MyUser, related_name="applicant") def get_absolute_url(self): return reverse('website:ProjectDetails', kwargs = {'pk1' : self.pk}) the view of my page with the link: class RecruitmentPage(generic.ListView): #import pdb; pdb.set_trace() model = Project template_name = "recruitment_index.html" def get_object(self, queryset=None): return get_object_or_404(Project, id=self.kwargs['pk1']) def get_context_data(self, **kwargs): context = super(RecruitmentPage, self).get_context_data(**kwargs) current_project_id = self.kwargs['pk1'] applicant_list = Project.objects.get(id = current_project_id).applicant.all() app_with_resp = [] app_without_resp = [] for i in applicant_list: if len(i.response_set.all())>0: app_with_resp.append(i) else: app_without_resp.append(i) context['current_project_id'] = current_project_id context['applicant_list'] = …
