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Django-taggit tag value retrieval and formatting failing

I am trying to implement a tagging process for profiles so you can add your hobbies for example.
I have chosen django-taggit as it seemed quite simple and does what I need it to, plus don't really know how to do it myself from scratch.
I have managed to make it work to some extent but I am having issues with 3 things:
Not really sure what's the best way to control the form field for these tags as I generate the form automatically with widget adjustments in meta function of the form, but it might work fine after resolving the below two issues.
When there is no data for the field hobbies (tags) the field gets populated with a single tag of value "[]" as per below image.
When I add a tag of "music" and submit the form after I reload the page I get this "[]" as per image. I assumed this will be dealt with by the library, but I cannot see another similar scenario online.
When I try adding another tag of "games" and save and reload, the below happens. The initial value gets wrapped again.
My model is:
class UserProfile(models.Model):
user = models.OneToOneField(User, on_delete=models.CASCADE)
hobbies = TaggableManager()
My form is:
class UserProfileForm(forms.ModelForm):
class Meta:
model = UserProfile
fields = ['hobbies',]
def __init__(self, *args, **kwargs):
super(UserProfileForm, self).__init__(*args,**kwargs)
self.fields['hobbies'].widget = forms.TextInput()
self.fields['hobbies'].widget.attrs['data-role'] = "tagsinput"
self.fields['hobbies'].widget.attrs['class'] = "form-control"
self.fields['hobbies'].required = False
My view function is:
if request.method == 'POST':
user_profile = UserProfile.objects.get(user=request.user)
form = UserProfileForm(request.POST, instance=user_profile)
print(form)
if form.is_valid():
obj = form.save(commit=False)
obj.user = request.user
obj.save()
print("Form valid")
form.save_m2m()
Using:
<script src="/static/js/tagsinput.js"></script>
<link rel="stylesheet" href="{% static 'css/tagsinput.css' %}" />

I had this exact same problem.
One solution is to apply the data-role="tagsinput" AFTER you turn a list of tags into a comma-separated string for the form.
Here is that solution:
class MyModelForm(forms.ModelForm):
class Meta:
model = MyModel
def __init__(self, **kwargs):
self.fields['tags'].widget.attrs['value'] = ", ".join(list(self.instance.tags.names()))
self.fields['tags'].widget.attrs['data-role'] = "tagsinput"
Output:
As you can see, there's a problem with quotes appearing around tags that are multi-word. It also causes new tags with quotes to be saved to the database.
If double-quotes didn't appear around multi-word phrases, this would be the most elegant solution. If someone solves this in the future, drop a note!
My template is this:
<div class="m-3 p-3 border">
<form method="POST" enctype="multipart/form-data">
{% csrf_token %}
{{ form|crispy }}
<button class="btn btn-primary" type="submit">Save Form</button>
</form>
</div>
I know I can use a template tag to strip the extra quotes from the tag field itself, but then I'd have to go through and create all the form fields manually just to set the tags template tag.
For the time being, my solution is to simply use Javascript and just modify the Meta widgets section of the form.
FINAL ANSWER (for now):
forms.py
class MyModelForm(forms.ModelForm):
class Meta:
model = MyModel
widgets = {
'tags': forms.TextInput(attrs={
"data-role": "tagsinput",
})
}
custom.js - put this script on the page that loads the form.
document.addEventListener("DOMContentLoaded", function(event) {
let tags_input = document.querySelector('#id_tags');
let tags_input_value = tags_input.value;
let new_value = [...tags_input_value.matchAll(/<Tag:\s*([\w\s]+)>/g)].map(([, m]) => m).join(', ')
tags_input.setAttribute('value', new_value);
}
So all we're doing is modifying the front-end presentation, and leaving all the backend internal forms functionality untouched.

So after quite a few (hundreds) of tests, I finally narrowed down where the issue was and tried to go around it with successful result.
It seems the data got amended into tag objects through tagsinput library I was using. Only when the "data-role" was specified as "tagsinput" in the forms.py the data would already come to html side as those objects and be shown incorrectly. So instead I wanted to keep the data clean and only apply data-role='tagsinput' in the end for visual aspect, which I did using:
var hobbiesTags = document.getElementById("id_hobbies");
if(hobbiesTags){
var att = document.createAttribute("data-role");
att.value = "tagsinput";
hobbiesTags.setAttributeNode(att);
};
And that resulted in the below. Maybe there are better ways to do this, I'm not sure, but it's a pretty clean solution. Share your alternatives.

How to use html form 'placeholder' property with standard view?

I am new to Django and am using Django's user auth package (django.contrib.auth) for user login, password reset, etc.
Now, while everything works just fine, on the logon form, I'd like to use the html-placeholder property. How can I use / populate this? I did find some answers (e.g. this one) but I do not understand where to place this code, how to extend the view / form or even the model (e.g. adding new fields) as this gets delivered with the standard package.
Right now, I have added the following:
forms.py
from django import forms
from django.contrib.auth.forms import AuthenticationForm
class LoginForm(forms.Form):
username = forms.CharField(label='username')
password = forms.CharField(label='password')
def __init__(self, *args, **kwargs):
super(LoginForm, self).__init__(*args, **kwargs)
self.fields['username'].widget.attrs['placeholder'] = 'Username'
self.fields['password '].widget.attrs['placeholder'] = 'Password'
I am not sure what I need to do in urls.py or models.py or anywhere else for the code to be executed.

I found the following solution:
installed bootstrap4
using the following tag in my html:
{% bootstrap_field form.password field_class="field" placeholder="Password" show_label=False %}

I believe by adding the widgets to your forms init, when you instantiate the form in your template the placeholder should appear like intended. Did you just try rendering your form such as {{form}} in the template and see if it rendered it? I dont think bootstrap4 is necessary but it is a great tool.

Django pass render_to_response template in other template

this is probably a question for absolute beginners since i'm fairly new to progrmaming. I've searched for couple of hours for an adequate solution, i don't know what else to do.
Following problem. I want to have a view that displays. e.g. the 5 latest entries & 5 newest to my database (just an example)
#views.py
import core.models as coremodels
class LandingView(TemplateView):
template_name = "base/index.html"
def index_filtered(request):
last_ones = coremodels.Startup.objects.all().order_by('-id')[:5]
first_ones = coremodels.Startup.objects.all().order_by('id')[:5]
return render_to_response("base/index.html",
{'last_ones': last_ones, 'first_ones' : first_ones})
Index.html shows the HTML content but not the content of the loop
#index.html
<div class="col-md-6">
<p> Chosen Items negative:</p>
{% for startup in last_ones %}
<li><p>{{ startup.title }}</p></li>
{% endfor %}
</div>
<div class="col-md-6">
<p> Chosen Items positive:</p>
{% for startup in first_ones %}
<li><p>{{ startup.title }}</p></li>
{% endfor %}
Here my problem:
How can I get the for loop to render the specific content?
I think Django show render_to_response in template comes very close to my problem, but i don't see a valid solution there.
Thank you for your help.
Chris
--
I edited my code and problem description based on the solutions provided in this thread

the call render_to_response("base/showlatest.html"... renders base/showlatest.html, not index.html.
The view responsible for rendering index.html should pass all data (last_ones and first_ones) to it.
Once you have included the template into index.html
{% include /base/showlatest.html %}
Change the view above (or create a new one or modify the existing, changing urls.py accordingly) to pass the data to it
return render_to_response("index.html",
{'last_ones': last_ones, 'first_ones' : first_ones})
The concept is that the view renders a certain template (index.html), which becomes the html page returned to the client browser.
That one is the template that should receive a certain context (data), so that it can include other reusable pieces (e.g. showlatest.html) and render them correctly.
The include command just copies the content of the specified template (showlatest.html) within the present one (index.html), as if it were typed in and part of it.
So you need to call render_to_response and pass it your data (last_ones and first_ones) in every view that is responsible for rendering a template that includes showlatest.html
Sorry for the twisted wording, some things are easier done than explained.
:)
UPDATE
Your last edit clarified you are using CBV's (Class Based Views).
Then your view should be something along the line:
class LandingView(TemplateView):
template_name = "base/index.html"
def get_context_data(self, **kwargs):
context = super(LandingView, self).get_context_data(**kwargs)
context['last_ones'] = coremodels.Startup.objects.all().order_by('-id')[:5]
context['first_ones'] = coremodels.Startup.objects.all().order_by('id')[:5]
return context
Note: personally I would avoid relying on the id set by the DB to order the records.
Instead, if you can alter the model, add a field to mark when it was created. For example
class Startup(models.Model):
...
created_on = models.DateTimeField(auto_now_add=True, editable=False)
then in your view the query can become
def get_context_data(self, **kwargs):
context = super(LandingView, self).get_context_data(**kwargs)
qs = coremodels.Startup.objects.all().order_by('created_on')
context['first_ones'] = qs[:5]
context['last_ones'] = qs[-5:]
return context

POSTing forms in Django's admin interface

I'm writing a Django admin action to mass e-mail contacts. The action is defined as follows:
def email_selected(self,request,queryset):
rep_list = []
for each in queryset:
reps = CorporatePerson.objects.filter(company_id = Company.objects.get(name=each.name))
contact_reps = reps.filter(is_contact=True)
for rep in contact_reps:
rep_list.append(rep)
return email_form(request,queryset,rep_list)
email_form exists as a view and fills a template with this code:
def email_form(request,queryset,rep_list):
if request.method == 'POST':
form = EmailForm(request.POST)
if form.is_valid():
cd = form.cleaned_data
send_mail(
cd['subject'],
cd['message'],
cd.get('email','noreply#localboast'),['redacted#email.com'],
)
return HttpResponseRedirect('thanks')
else:
form = EmailForm()
return render_to_response('corpware/admin/email-form.html',{'form':form,})
and the template exists as follows:
<body>
<form action="/process_mail/" method="post">
<table>
{{ form.as_table }}
</table>
<input type = "submit" value = "Submit">
</form>
</body>
/process_mail/ is hardlinked to another view in urls.py - which is a problem. I'd really like it so that I don't have to use <form action="/process_mail/" method="post"> but unfortunately I can't seem to POST the user inputs to the view handler without the admin interface for the model being reloaded in it's place (When I hit the submit button with , the administration interface appears, which I don't want.)
Is there a way that I could make the form POST to itself (<form action="" method="post">) so that I can handle inputs received in email_form? Trying to handle inputs with extraneous URLs and unneeded functions bothers me, as I'm hardcoding URLs to work with the code.

You can use django's inbuilt url tag to avoid hardcoding links. see...
http://docs.djangoproject.com/en/dev/ref/templates/builtins/#url
Chances are you'd be better off setting up a mass mailer to be triggered off by a cron job rather than on the post.
Check out the answer I posted here
Django scheduled jobs
Also if you insist on triggering the email_send function on a view update perhaps look at
http://docs.djangoproject.com/en/dev/topics/signals/

How to implement a "back" link on Django Templates?

I'm tooling around with Django and I'm wondering if there is a simple way to create a "back" link to the previous page using the template system.
I figure that in the worst case I can get this information from the request object in the view function, and pass it along to the template rendering method, but I'm hoping I can avoid all this boilerplate code somehow.
I've checked the Django template docs and I haven't seen anything that mentions this explicitly.

Actually it's go(-1).
<input type=button value="Previous Page" onClick="javascript:history.go(-1);">

This solution worked out for me:
Go back
But that's previously adding 'django.core.context_processors.request', to TEMPLATE_CONTEXT_PROCESSORS in your project's settings.

Back
Here |escape is used to get out of the " "string.

Well you can enable:
'django.core.context_processors.request',
in your settings.TEMPLATE_CONTEXT_PROCESSORS block and hook out the referrer but that's a bit nauseating and could break all over the place.
Most places where you'd want this (eg the edit post page on SO) you have a real object to hook on to (in that example, the post) so you can easily work out what the proper previous page should be.

You can always use the client side option which is very simple:
Back

For RESTful links where "Back" usually means going one level higher:
<input type="button" value="Back" class="btn btn-primary" />

All Javascript solutions mentioned here as well as the request.META.HTTP_REFERER solution sometimes work, but both break in the same scenario (and maybe others, too).
I usually have a Cancel button under a form that creates or changes an object. If the user submits the form once and server side validation fails, the user is presented the form again, containing the wrong data. Guess what, request.META.HTTP_REFERER now points to the URL that displays the form. You can press Cancel a thousand times and will never get back to where the initial edit/create link was.
The only solid solution I can think of is a bit involved, but works for me. If someone knows of a simpler solution, I'd be happy to hear from it. :-)
The 'trick' is to pass the initial HTTP_REFERER into the form and use it from there. So when the form gets POSTed to, it passes the correct, initial referer along.
Here is how I do it:
I created a mixin class for forms that does most of the work:
from django import forms
from django.utils.http import url_has_allowed_host_and_scheme
class FormCancelLinkMixin(forms.Form):
""" Mixin class that provides a proper Cancel button link. """
cancel_link = forms.fields.CharField(widget=forms.HiddenInput())
def __init__(self, *args, **kwargs):
"""
Override to pop 'request' from kwargs.
"""
self.request = kwargs.pop("request")
initial = kwargs.pop("initial", {})
# set initial value of 'cancel_link' to the referer
initial["cancel_link"] = self.request.META.get("HTTP_REFERER", "")
kwargs["initial"] = initial
super().__init__(*args, **kwargs)
def get_cancel_link(self):
"""
Return correct URL for cancelling the form.
If the form has been submitted, the HTTP_REFERER in request.meta points to
the view that handles the form, not the view the user initially came from.
In this case, we use the value of the 'cancel_link' field.
Returns:
A safe URL to go back to, should the user cancel the form.
"""
if self.is_bound:
url = self.cleaned_data["cancel_link"]
# prevent open redirects
if url_has_allowed_host_and_scheme(url, self.request.get_host()):
return url
# fallback to current referer, then root URL
return self.request.META.get("HTTP_REFERER", "/")
The form that is used to edit/create the object (usually a ModelForm subclass) might look like this:
class SomeModelForm(FormCancelLinkMixin, forms.ModelForm):
""" Form for creating some model instance. """
class Meta:
model = ModelClass
# ...
The view must pass the current request to the form. For class based views, you can override get_form_kwargs():
class SomeModelCreateView(CreateView):
model = SomeModelClass
form_class = SomeModelForm
def get_form_kwargs(self):
kwargs = super().get_form_kwargs()
kwargs["request"] = self.request
return kwargs
In the template that displays the form:
<form method="post">
{% csrf token %}
{{ form }}
<input type="submit" value="Save">
Cancel
</form>

For a 'back' button in change forms for Django admin what I end up doing is a custom template filter to parse and decode the 'preserved_filters' variable in the template. I placed the following on a customized templates/admin/submit_line.html file:
<a href="../{% if original}../{% endif %}?{{ preserved_filters | decode_filter }}">
{% trans "Back" %}
</a>
And then created a custom template filter:
from urllib.parse import unquote
from django import template
def decode_filter(variable):
if variable.startswith('_changelist_filters='):
return unquote(variable[20:])
return variable
register = template.Library()
register.filter('decode_filter', decode_filter)

Using client side solution would be the proper solution.
Cancel