Django community: RSS
This page, updated regularly, aggregates Django Q&A from the Django community.
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Looping through two arrays and adding the collection of each into new array without dups
I have two arrays that I want to loop through. Array A and Array B. I want to add the elements of both array into a new Array that contains the collection of all elements in that array without any duplication. This will be written in python. For Example A = [1,2,3,4] B = [1,5,6,7] Collection = [1,2,3,4,5,6,7] I was wondering if there's a faster and more efficient to do it without looping through each indexes and comparing it and then storing it. Because that's what I'm planning to do but I think it will take really long time given that I have about a couple thousand elements in each array. -
Image won't load to template in Django, but is stored to Media file
I'm trying to get a posted image to display on a Listview Blog application. Models.py from django.db import models class Post(models.Model): image = models.ImageField(upload_to='Post_images',null=True) title = models.CharField(max_length=100) content = models.TextField() date_posted = models.DateTimeField(default=timezone.now) author = models.ForeignKey(User, on_delete=models.CASCADE) success_url = "post-detail" template_name = 'post_form.html' urls.py from django.conf.urls.static import static from django.conf import settings if settings.DEBUG: urlpatterns += static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT) urlpatterns += static(settings.STATIC_URL, document_root=settings.STATIC_ROOT) home.html {% extends "blog/blogbase.html" %} {% block content %} {% for post in posts %} {% if Post.image %} <img src="{{ post.image.url }}" class="img-responsive"> {% else %} <span class="text-muted">No cover</span> {% endif %} {% endfor %} I see "No cover printed" on all of the posts indicatign that Post.image is not registering. settings.py MEDIA_ROOT = os.path.join(BASE_DIR, '/media') MEDIA_URL = '/media/' STATIC_ROOT = os.path.join(BASE_DIR, '/static') STATIC_URL = '/static/' I think it has to do with the media root, because when I upload the image it saves to the media file. I think the html/urls/settings connection is messed up. -
Python / Django / channels.exception.ChannelFull() error
We constantly get a channels.exception.ChannelFull() error when we run our setup. Traceback Our setup consists of: Server Computer Client Computer The Client connects via websocket to the Server. It sends and receives to the Server over this link. The Server runs Django with Redis (channels-redis) and Channels2 in ASGI mode. When a client connects, the specific.channel_id is stored in our database. When a client disconnects, it is removed from our database. We run a BackgroundScheduler Job at 5 second intervals. This Job gets the clients in the DB and sends each one (via specific.channel_id) a message. The Client receives this message over websocket, processes it, and sends the requested data back to the Server where it is processed through a WebsocketConsumer. When developing, we ran short tests (<2 min). It wasn't until later when we were running longer tests (2+ mins) that we started to encounter this error. What might we have missed? -
Django Model matching query does not exist on newly created instances
So I been seeing the same question posted in different scenarios and I am unable to get mine to work. Basically trying to find a model instance if it already exists and create a new one if it doesn't - based on if the instance have the same field as the user's username I tried get_object_or_404 and even changing the primary key to a field in the model class. this is the models.py class Cart(models.Model): user = models.CharField(max_length=30) @classmethod def create(cls, user): user = cls(user=user) return user def __str__(self): """String for representing the Model object.""" return f'{self.id} {self.user}' this is the views.py def cart(request, pk): try: pizza = PizzaInstance.objects.get(id=pk) # get the topping(s) topping_1 = int(request.POST["topping1"]) topping = PizzaTopping.objects.get(pk=topping_1) # get the username user = request.user.username # check if the user already has an order try: order = Cart.objects.get(user=user) except KeyError: order = Cart.create([user]) order.save() I expected to see the order being saved and a new instance being created or even new instances added to the cart. error is get is - Cart matching query does not exist. Thank you! -
Django Rest Framework custom Permission Class with ManyToManyField
I am trying to write a permission class for django rest api view. this is my models from django.db import models from django.contrib.auth.models import User class Profile(models.Model): name = models.CharField(max_length=50) auth_user = models.OneToOneField(User, on_delete=models.CASCADE) class Group(models.Model): admin = models.ManyToManyField(Profile, related_name='g_admin') members = models.ManyToManyField(Profile, related_name='g_mess') I want only group admin can perform an action in particular pages, for this i am writing a permission class: class IsGroupAdmin(BasePermission): """ Allows access only to Group Admin. """ def has_permission(self, request, view): # return bool() do something here I am going through trouble to write the permission class to check if group admin or not. i am facing issue coz, this is many to many field. can anyone help me to write this? -
Datatables: How to show a message while data is exported (Excel, PDF, etc)?
I use DataTables buttons plugin to export my data to Excel, PDF, etc. But when many rows of data have to be exported the process sometimes takes a lot of time while the file is created, I like to show a message that indicates the download is in progress until the 'save as' window appears. I only have implemented the standard buttons configuration in the inicialization of datatable. Many thanks in advance for any idea or suggestion. -
Model field to hold any number of possible values from a finite list of choices
Say I have an abstract Product model with 'shipping' field on it, and I want that field to hold any number of possible values from a finite list of choices. So, if my choices list is: [ ('fedex', 'FedEx'), ('company2', 'Company 2'), ('company3', 'Company 3'), ... ] ...the model field should be able to hold one or more (or all) values from the list. What field should I use and how should I design my model? -
Django Student-Teacher ManyToMany relationship
I'm trying to model a Many to Many Teacher/Student relationship. Both the teachers and the students are objects of class Users (I edited out some unrelated fields). I'm having problems in understanding how the relationship should work. Basically, I want to be able to do something like u1 = User.objects.get(pk=<student pk>) u1.teachers.all() u2 = User.objects.get(pk=<teacher pk>) u2.students.all() After reading some docs and tutorials, this is how I defined the User class and the StudentTeacher relationship: class User(AbstractUser): is_student = models.BooleanField('student status', default=False) is_teacher = models.BooleanField('teacher status', default=False) teachers = models.ManyToManyField('self', through="StudentTeacher", through_fields=('student', 'teacher'), symmetrical=False) students = models.ManyToManyField('self', through="StudentTeacher", through_fields=('teacher', 'student'), symmetrical=False) class StudentTeacher(models.Model): teacher = models.ForeignKey(User, related_name='students', on_delete=models.CASCADE, limit_choices_to={'is_teacher': True}) student = models.ForeignKey(User, related_name='teachers', on_delete=models.CASCADE, limit_choices_to={'is_student': True}) This is what happens when I try to generate migrations (wiscom is the name of my application): wiscom.StudentTeacher.student: (fields.E302) Reverse accessor for 'StudentTeacher.student' clashes with field name 'User.teachers'. HINT: Rename field 'User.teachers', or add/change a related_name argument to the definition for field 'StudentTeacher.student'. wiscom.StudentTeacher.student: (fields.E303) Reverse query name for 'StudentTeacher.student' clashes with field name 'User.teachers'. HINT: Rename field 'User.teachers', or add/change a related_name argument to the definition for field 'StudentTeacher.student'. wiscom.StudentTeacher.teacher: (fields.E302) Reverse accessor for 'StudentTeacher.teacher' clashes with field name 'User.students'. HINT: Rename … -
User defined template Django
Is there a way to enable application users to create their own template within the django app? One example would be how MailChimp enables users to create their own custom email template. Currently i'm thinking of creating a model that captures information the user wants to display. that model can point to a template and populate it with the information the user wants to display. But is there a better way? -
Can't start gunicorn.service on VirtualBox with CentOS 8, Nginx and Django-Rest-Framework
Trying to deploy django application using gunicorn and nginx on CentOS. Following DigitalOcean tutorial: https://www.digitalocean.com/community/tutorials/how-to-set-up-django-with-postgres-nginx-and-gunicorn-on-centos-7 But I have CentOS 8. I can run my application localy from virtualenv using: python manage.py runserver gunicorn --bind 0.0.0.0:8000 app.wsgi:application but then I try to run gunicorn.service I have status - failed. inside of systemctl status gunicorn.service I have started gunicorn deamon gunicorn.service: main process exited, code=exited, status=203/EXEC gunicorn.service: failed with result 'exit-code' Without this file I can't bind app.sock file as it not being created. My gunicorn.service looks like this app - is fictional application name :) admin - is a real user of this system [Unit] Description=gunicorn daemon After=network.target [Service] User=admin Group=nginx WorkingDirectory=/home/admin/app/portal/app ExecStart=/home/admin/app/env/bin/gunicorn --workers 3 --bind unix:/home/admin/app/portal/app/app.sock app.wsgi:application [Install] WantedBy=multi-user.target There is a tree of my project: app - env - portal -- client -- app --- documents --- fixtures --- images --- app ---- __init__.py ---- settings.py ---- urls.py ---- wsgi.py --- app_project ---- ... --- manage.py --- requirements.txt What can be done to make it work and that chan I check to find more clues why it doesn't work? Any input is welcome. Thanks -
Django using custom HTML form without Form model
I'm trying to use a custom login page and HTML form with Django but I'm not sure how to configure the application's urls.py. Here is my HTML form: <form method="POST" action="{% url 'users:login' %}"> {% csrf_token %} <div class="field"> <div class="control"> <select class="bureau_select" name="bureau" autofocus=""> <option value="FNC">Finance</option> <option value="HR">HR</option> <option value="CRT">Creative</option> </div> </div> <div class="field"> <div class="control"> <input class="input" type="text" name="username" placeholder="Name" autofocus=""> </div> </div> <div class="field"> <div class="control"> <input class="input" type="password" name="userpassword" placeholder="Password"> </div> </div> <button class="button">Login</button> </form> users is the application I've made to handle things like auth, changing user profile, etc. My users app looks like this: urls.py from django.urls import path from . import views app_name='users' urlpatterns = [ path('login/', views.CustomLoginView.as_view(), name='login'), ] views.py from django.shortcuts import render from django.urls import reverse_lazy from django.contrib.auth.views import LoginView from django.contrib.auth.forms import ( AuthenticationForm, PasswordChangeForm, PasswordResetForm, SetPasswordForm, ) from django.contrib.auth import authenticate, login class CustomLoginView(LoginView): # form_class = AuthenticationForm template_name = 'users/login.html' def login_user(request, user_id): if request.POST: username = request.POST['username'] password = request.POST['password'] user = authenticate(username=username, password=password) if user is not None: login(request, user) # Redirect to a success page. ... else: # Return an 'invalid login' error message. ... (following Django docs) I'm aware I can create this … -
Fix bootstrap table in weasyprint generated PDF
I'm trying to create a PDF table with Weasyprint in my Django website. The same table is shown in a html page and with Weasyprint. When I use bootstrap colors in the html version it shows correctly, but the colors are lost on the Weasyprint version. That is the only feature missing on the Weasyprint version, which works otherwise. views.py @login_required def scale_answer_pdf(request, scale_id): scale = get_object_or_404(UserScale, pk=scale_id) if scale.user == request.user or request.user.is_superuser: if scale.scale_meta.title == "Now": choices = NowLegend class ScaleForm(forms.ModelForm): class Meta: model = NowModel fields = labellist(NowLabels) labels = NowLabels if scale.scale_meta.title == "Child": choices = NowLegend class ScaleForm(forms.ModelForm): class Meta: model = ChildModel fields = labellist(ChildLabels) labels = ChildLabels form = ScaleForm(instance=scale) **html = render_to_string('diagnosis/scale_answer_pdf.html', {'form': form, 'scale':scale, 'choices':choices}) response = HttpResponse(content_type='application/pdf') response['Content-Disposition'] = 'filename="{} - {} - {}.pdf"'.format(scale.scale_meta.title, scale.user.username, scale.created.strftime('%Y-%m-%d')) weasyprint.HTML(string=html, base_url=request.build_absolute_uri()).write_pdf(response, presentational_hints=True, stylesheets= [weasyprint.CSS(settings.STATIC_ROOT + '/css/sb-admin-2.min.css'), weasyprint.CSS(settings.STATIC_ROOT +'/css/all.min.css')]) return response** else: raise Http404 html for the PDF - the boostrap CSS works, and the table is also showing. But the colors from the table don't. I highlight the table parts that don't show colors {% extends "base_pdf.html" %} {% load i18n %} {% load staticfiles %} {% load get_item %} {% block content … -
During TestCase execution django.db.connection.cursor() SQL query returning data from main DB, not from the test one
Dears, I'm facing a problem which I have no more ideas how to resolve. I have need to test data which is returned by direct query from database. During execution of TestCase django.db.connection.cursor() is returning data from main database, not from test one, which contain fixtures prepared for this test purposes. I've tried to use both TestCase and TransactionalTestCase. I've tried debugging, checking variables values and found out that connection is pointed onto test database for sure. Do you know why it's returning data from main database? Is there any case when Django is copying data from main database to this created for tests purposes? I'm using: Python 3.6.5, Django 2.1, pytest 4.6.3, pytest-django 3.5 Thanks in advance for any support. -
How may seconds may an API call take until I need to worry?
I have to ask a more or less non-typical SO question and hope you don't mind. Right now I am developing my very first web application. I did set up an AJAX function that requests some data from a third party API and populates my html containers with the returned data. Right now I query one single object and populate 3 html containers with around 15 lines of Javascript code. When i activate the process/function by clicking a button on my frontend, it needs around 6-7 seconds until the html content is updated. Is this a reasonable time? The user experience honestly will be more than bad considering that I will have to query and manipulate far more data (I build a one-site dashboard related to soccer data). There might be very controversal answers to that question, but what would be a fair enough time for the process to run using standard infrastructure? 1-2 seconds? (I will deploy the app on heroku or digitalocean and will implement a proper caching environment to handle "regular visitors"). Right now I use a virtualenv and django server for the development and a demo server from the third party API which might be slowed … -
Problems with nginx+gunicorn resolving static content
I am setting up an environment with a django application (askbot opensource project), gunicorn and nginx. With nginx and gunicorn in different docker containers. This is my nginx configuration. server { listen 80; location /static { alias /askbot/static; } location /m { alias /askbot/static; } location / { proxy_set_header Host $host; proxy_set_header X-Real-IP $remote_addr; proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for; proxy_pass http://askbot:8080/; } } If I run the django app on debug mode, everything is ok, I can go through nginx and I see how nginx is only invoking gunicorn for the dynamic content, and the static content is resolved locally. But, when I run the django application with debug false, nginx does not revolve the static content, and if I see the source code for the web page, I can see all the paths for the static content have changed, using somethign like "/m/CACHE...". I guess this is the reason why nginx cannot resolve the static content anymore. For example, when using debug mode equals false, this is one fragment of the html source code. <link rel="stylesheet" href="/m/CACHE/css/9275d0e5b87f.css" type="text/css" /> <link href="//fonts.googleapis.com/css?family=Open+Sans+Condensed:700&amp;subset=latin-ext" rel="stylesheet" type="text/css" /> <link href="//fonts.googleapis.com/css?family=Open+Sans+Condensed:700&amp;subset=cyrillic-ext" rel="stylesheet" type="text/css" /> <script type="text/javascript" src="/m/default/media/jslib/modernizr.custom.js?v=1"></script> <script type="text/javascript"> And when running with debug equals false, … -
Backend in a hosting using Django and cpanel
I need help with my project, I am working on an application using Django as a backend and Angular as a fronted, I would like to know how to upload my Django backend to the hosting cpanel using MYSQL or PostgreSql. Or do I have to upload the full backend, or can I only upload the database? Thank you -
django rest framework offline documentation
I need to get the documentation for django rest framework for offline usage, Why? b/c I live in Ethiopia and the internet is too damn slow for me to go online just to the doc of APIView. So does anybody know of a link where I can find the offline version of the documentation? The pdf on readthedoc is outdated and empty and I can't seem to find any other alternative. Can anyone help? -
Django filter with manytomanyfield
This is my models class Person(models.Model): name = models.CharField(max_length=50) is_group_member = models.BooleanField(default=False) class Group(models.Model): members = models.ManyToManyField(Person) @receiver(post_save, sender=Group) def set_group_member_type(sender, instance, created, **kwargs): if created: # change the all group members' type I am trying to update is_group_member field with signal. When a group is created with members, then i will filter and retrieve all the person who are group member, then i will change the is_group_member value to True Can anyone help me to achieve this? -
Get response empty fields error after passing form to django rest api
I'm trying to build passing formdata to api page. But, the response is empty fields error. This is my vue template. <b-form @submit.prevent="postImitagram" id="post-form"> <b-form-input id="words" v-model="content" :state="state" trim /> <b-form-file accept="image/*" id="image" v-model="file" :state="Boolean(file)" /> <b-button block class="mt-5" type="submit" variant="primary">submit </b-button> </b-form> data() { return { content: "", file: null, error: '' } }, methods: { postImitagram(e) { let endpoint = "/api/posts/"; let method = "POST"; let formData = new FormData(); formData.append('title', this.content); formData.append('image', this.test, this.test.name); let context = {'title': this.content, 'image': this.file}; apiService(endpoint, method, formData).then(data => { }) } } function apiService(endpoint, method, data) { const config = { method: method || "GET" body: data, headers: { 'content-type': 'multipart/form-data', 'X-CSRFTOKEN': CSRF_TOKEN } }; return fetch(endpoint, config) .then(handleResponse) .catch(error => console.log(error)) } api model { "title": "", "image": null } and response status 400 bad request and 'title' and 'image' field are required. Creating a new one works fine when i post things in api page itself. What did I miss? Thank you in advance -
Django API Chart.js
Im would like to change the Chart Type from Bar Chart to Line Chart with an ajax call. For a start I saved the Chart Types (Bar, Line, Scatter) in a Model as follows: class Chart(models.Model): ctype = models.CharField(max_length=20, choices=choices, default='bar') choices = ( ('line', 'line'), ('bar', 'bar'), ('radar', 'radar'), ('bubble', 'bubble'), ('scatter', 'scatter'), ) and I pass them to view, serialising them and passing them on class ChartData(APIView): def get(self,request,format=None): dataset = Mobiles.objects.all() serializer = TypeSerializer(dataset,many=True) ctype = serializer.data data = { "ctype":[item["ctype"] for item in ctype], } return Response(data) to the api which returns: "ctype": [ "bar", "bar", "bar", ] And finally I retrieve them from the api, and set them equal to the chart type. var endpoint = '/api/chart/data/' var price = [] var labels = [] var ctype = [] $.ajax({ method: 'GET', url: endpoint, success: function(data){ labels = data.labels price = data.price ctype = data.ctype setChart() }, error:function(error_data){ console.log("error") console.log(error_data) } }) function setChart(){ var ctx = document.getElementById("myChart"); var myChart = new Chart(ctx, { type: ctype, data: { labels: labels, datasets: [{ label: '#', data: price, }] } }) } But the chart does not work Thank you for any help -
Implementing one to many between an article and page models in Wagtail
I'm trying to setup a wagtail site with an article to pages structure but I'm struggling. A review article for example may have an introduction page, a benchmark page and a conclusion page. I want to work out how to allow this relationship in wagtail and have it so that editors can add multiple pages to the same article on the same page. I can imagine the pages interface looking a bit like how you have content, promote and settings on pages but with the ability to add, rename and reorder pages. I've tried using a foreign key on a page model that links to an article but I can't get it to be shown in the admin the way I want. -
How do i count objects that has an id below the current id in django
class Shoe(models.Model): title = models.Charfield(max_length=120) the querry, i am using is old_shoes = Shoe.objects.all().count() i want to get shoes with id's below the current id, would something like this work old_shoes = Shoe.objects.all(id>shoe.id).count() -
Collectstatic is giving NoSuchKey while using s3boto3 and manifestfilemixin
class NSStaticStorage(ManifestFilesMixin, S3Boto3Storage): pass NoSuchKey: An error occurred (NoSuchKey) when calling the ListObjects operation: The specified key does not exist. I am getting this error while integrating s3boto and manifest for cache busting -
Django push notification, editing the content dynamically
I have a function which register a new user then i wanna send a email with a message, i know how to do that writing a message into code, but i want some way to make it more dynamic editing this message in admin or any page but not in code, just like "Notification – Custom Notifications and Alerts for WordPress" does. Basically when i edit this message in admin or other page the content which fuction send is changes as well. -
Django Pagination - re group and show group of times per page?
Im currently regrouping some data and then displaying that data in columns whilst also using pagination. However, due to the ordering of the origin data, there are instances where column 1 has 1 entry in but actually has 5 or 6 total entries, but they would be on different pages, is it possible to regroup the data so that the number of items per page is taken by the number of grouped items? I thought about sorting the data before posting it to the page but then that will only show the one column of types per page (there could be 1 or n types/columns that id like to have on one page) note: the sample data below is not actual data, The below example hopefully will make things clearer orgin data: ID Type Item ---------------------------- 9 Fruit Apple 15 Meat Beef 18 Fruit Lemon 99 Fruit Orange 9 Fruit Grape 77 Meat Chicken Paginated and grouped data current output Meat Fruit ------- ------- Beef Apple Lemon page 1 of 2 (3 items per page) Meat Fruit ------- ------- Chicken Orange Grape page 2 of 2 (3 items per page) Desired Output Meat Fruit ------- ------- Beef Apple Chicken Lemon …
