Django: how do i edit/update a model? - django

Argh. Hey all, i have a muy simple django question:
And argh, i'm sorry, i've read and read, and I am sure this is covered somewhere super-obviously, but i haven't found it!
How do i edit/update a model using django? Like, the data values? Not the model fields?
Here is my code! (I'm using a home-brew version of stuff!)
Here is the urls:
url(r'^editStory/(?P<id>\d+)$',
StoryModelView.as_view(
context_object_name='form',
template_name ='stories/editStory.html',
success_template= 'stories/editStorySuccess.html'
),
{},
'editStory'
),
Here is the view:
def get(self,request,id=None):
form = self.getForm(request,id)
return self.renderValidations(form)
def getForm(self, request,id):
if id:
return self.getModelById(request,id)
return StoryForm()
def getModelById(self,request,id):
theStory = get_object_or_404(Story, pk=id)
if theStory.user != request.user:
raise HttpResponseForbidden()
return StoryForm(theStory)
def renderValidations(self,form):
if self.context_object_name:
contextName = self.context_object_name
else:
contextName = 'form'
if self.template_name:
return render_to_response(self.template_name,{contextName:form})
else :
return render_to_response('stories/addStory.html',{contextName:form})
def getPostForm(self,request,id):
if id:
theStory = self.idHelper(request,id)
return StoryForm(request.POST,theStory)
return StoryForm(request.POST)
def processForm(self,form,request):
theStory = form.save(commit=False)
theStory.user = request.user
return theStory
Here is the template code:
{% block content %}
<h3>Edit story</h3>
<form action="" method="post">
{% csrf_token %}
{% for field in form %}
<div class="fieldWrapper">
{{ field.errors }}
{{ field.label_tag }} {{ field }}
</div>
{% endfor %}
<input type="submit" value="Submit"/>
</form>
{% endblock %}
try as i might, i either:
get an error
get nothing
i get an error with the code as-displayed, caused by this line
{% for field in form %}
and with the error of:
Caught AttributeError while rendering: 'Story' object has no attribute 'get'
or i get nothing - no data at all - if i change my "getModelById" method to read:
def getModelById(self,request,id):
theStory = get_object_or_404(StoryForm, pk=id)
if theStory.user != request.user:
raise HttpResponseForbidden()
return theStory
StoryForm is one of those "ModelForm" things, and its model is "Story".
SO! The question:
how do i fix this code to make it work? What have i done wrong?

You don't show what your class is inheriting from, but it seems like you're just using a standard single object display view. Instead, you should use one of the editing mixins that are provided for this purpose.

Without knowing what your model looks like, are you looking for something along the lines of
s = Story.objects.get(some criteria)
s.user = <some user>
s.save()
?
Sorry, I find your question a little vague.
Upon rereading, one thing jumped out at me:
You can't do a query (get, filter, or any variation on these) on a model-- you have to do it on an object manager, like objects.
So, as above, in your case, Story.objects.get_object_or_404 should solve your error.

Related

WTForms - Pass argument to form then create fields if variable exists

Depending on the arguments I pass to the form I want to return different form fields.
class TestForm(FlaskForm):
"""Test Form."""
if one:
field1 = StringField('Field 1')
if two:
field2 = StringField("Field 2")
if three:
field3 = StringField("Field 3")
submit = SubmitField("Add Service")
def __init__(self, one=None, two=None, three=None, *args, **kwargs):
super().__init__(*args, **kwargs)
self.one = one
self.two = two
self.three = three
I am not able to see the arguments when doing the if statements.
I am aware of the option to have logic in html when rendering the form, however due the nature of the project have opted to use quick_form on the html side.
Here is the html code I am using.
{% import 'bootstrap/wtf.html' as wtf %}
<h3 >Add Service</h3>
<div class="row">
<div class="col-md-4">
{{ wtf.quick_form(form) }}
</div>
</div>
Instead of creating this logic in your form class. I would recommend to create all the fields you need and then dynamically choose which to show the user using jinja2 in your html file.
Here's an example.
{% for fields in fields_list %}
{% if field == '1' %}
{{ form.field1.label(class="form-control-label") }}
{{ form.field1(class="form-control form-control-lg") }}
{% endif %}
{% if field == '2' %}
{{ form.field2.label(class="form-control-label") }}
{{ form.field2(class="form-control form-control-lg") }}
{% endif %}
{% if field == '3' %}
{{ form.field3.label(class="form-control-label") }}
{{ form.field3(class="form-control form-control-lg") }}
{% endif %}
{% endfor %}
And then when you render or redirect to your .html from your routes code, don't forget to send
the proper arguments, such as
# create your fields list, which do I want to show?
# Make it a list of integers
fields_list = [1, 2, 3]
return render_template('insert-name.html', fields_list , form=form)
If my answer helped you, please consider accepting my answer.
I am new to this site and trying to build up some reputation :)
Thank you! Happy Coding!
If someone ever comes accross the same question, here is a quick solution I came upon some times ago.
It is in part inspired from the accepted answer here.
In your forms.py or wherever you declare your TestForm class, put the class declaration inside a function that takes your parameter as an argument and returns the class object as output.
The argument will now be accessible within the class itself, allowing for any test you may want to perform.
Here's a working example based on your original question (I just added a default value to get at least one StringField in case the parameter is ommited):
def create_test_form(var='one'):
class TestForm(FlaskForm):
"""Test Form."""
if var == 'one':
field1 = StringField('Field 1')
if var == 'two':
field2 = StringField("Field 2")
if var == 'three':
field3 = StringField("Field 3")
submit = SubmitField("Add Service")
return TestForm()
Then simply create the form in your routes like so:
form = create_test_form('two')
Finally pass it to your HTML to render the form with quick_form like you did.
This example will render a form with a single StringField named "Field 2" and a "Add Service" submit button.

Error : MultiValueKeyError at /quiz/2/11 'choice'

I am creating a multi-choice quiz app, I have created a view which shows the question and 4 option. I have given radio button to each option but is giving me this error:
MultiValueDictKeyError at /quiz/2/11/ 'choice'
views.py
def question_detail(request,question_id,quiz_id):
q = Quiz.objects.get(pk=quiz_id)
que = Question.objects.get(pk=question_id)
ans = que.answer_set.all()
selected_choice = que.answer_set.get(pk=request.POST['choice'])
if selected_choice is True:
come = que.rank
came = come + 1
later_question = q.question_set.get(rank=came)
return render(request,'app/question_detail.html',{'que':que , 'later_question':later_question, 'ans':ans})
else:
come = que.rank
later_question = q.question_set.get(rank=come)
return render(request, 'app/question_detail.html', {'que': que, 'later_question': later_question, 'ans': ans})
question_detail.html
<form action="{% 'app:detail' quiz_id=quiz.id question_id=que.id %}" method="post">
{% csrf_token %}
{% for choice in que.answer_set.all %}
<input type="radio" name="choice" id="choice{{forloop.counter}}" value="{{choice.id}}">
<label for="choice{{forloop.counter}}">{{choice.answer}}</label>
{% endfor %}
</form>
Okay like I said in my comment, you're most likely getting that error because the POST object will be empty during a normal GET request. So you should wrap everything that's meant to happen after a request in an IF block:
if request.method === 'POST':
selected_choice = que.answer_set.get(pk=request.POST['choice'])
# Every other post-submit task
You should always check for the POST method in your views if you're expecting form data. Others have answered this more in-depth before so I would just direct you there:
What does request.method == "POST" mean in Django?

Sphinx search on Django raise exception TypeError at /search/

I am trying out to build full-text searching by using sphinx search, postgresql & django based on this tutorial: http://pkarl.com/articles/guide-django-full-text-search-sphinx-and-django-sp/.
All setup done for sphinx & postgresql and it works but I got trouble when reach on Sample Django code part.
In django views & urlconf, I only changed the function of *search_results* into search and Story model with my own model. For URLConf, I only changed *search_results* into search just same like on views and nothing changed made on search template.
So when I try to search from my form in Django, I get exception:
TypeError at /search/
list() takes exactly 1 argument (0 given)
I also try to changed based on steyblind's comment by change the urlpattern & view definition like this:
(r'^search/(.*)?', search),
def search(request, query=''):
but still keep get TypeError exception.
Is there any mistake I am doing here? Thanks in advance.
Here's my snippets:
Urls.py
(r'^search/(.*)', search),
Views.py
def search(request, query):
try:
if(query == ''):
query = request.GET['query']
results = Flow.search.query(query)
context = { 'flows': list(results),'query': query, 'search_meta':results._sphinx }
except:
context = { 'flows': list() }
return render_to_response('search.html', context, context_instance=RequestContext(request))
search.html
{% extends "base.html" %}
{% block main %}
<div>
<form action="/search/" method="GET">
<input type="text" name="query"/>
<input type="submit">
</form>
{% if flows %}
<p>Your search for “<strong>{{ query }}</strong>” had <strong>{{ search_meta.total_found }}</strong> results.</p>
<p>search_meta object dump: {{ search_meta }}</p>
{% endif %}
<hr/>
{% for s in flows %}
<h3>{{ s.title }}</h3>
<p>(weight: {{ s.sphinx.weight }})</p>
<p>story.sphinx object dump: {{ s.sphinx }}</p>
{% empty %}
<p>YOU HAVEN'T SEARCHED YET.</p>
{% endfor %}
</div>
{% endblock %}
Correct me if I'm wrong, but Django-Sphinx seems to be an abandoned project. The last update to it was a year ago, with most updates being 3-5 years ago. Also, I cannot speak for Django then, but it can do now, out of the box, what you are trying to do with Sphinx.
What version of Django and Python are you using? The error you are getting is strange as list() can take no arguments. Try this in a python shell:
>> list()
[]
Regardless, I've made a few modifications to the code that could possibly help fix the issue. However, if there are no results, you are passing 'flows' as empty in this line:
context = { 'flows': list() }
If you look at the template, this really accomplishes nothing.
urls.py:
(r'^search/', search),
views.py:
def search(request):
query = request.GET.get('query')
if query:
results = Flow.search.query(query)
if results:
context = { 'flows': list(results),'query': query, 'search_meta':results._sphinx }
else:
context = { 'flows': list() }
return render_to_response('search.html', context, context_instance=RequestContext(request))
All that said, I'd highly suggest that since this project is so outdated that you use your own search. Or if you need more functionality, you could use a search app like Haystack which is updated frequently. Using the same urls.py as above, you could implement the below as an easy search that will return all results for a blank search, the actual filtered results for a query.
views.py:
def search(request):
query = request.GET.get('q')
results = Flow.objects.all()
if query:
results = results.query(query)
return render_to_response('search.html', {"flows": results,}, context_instance=RequestContext(request))

Django: Multiple date fields in forms that allow blank entry issue

I have a model in Django that allows blanks for two date fields:
class ReleaseStream(models.Model):
name = models.CharField(max_length=200,db_column='name')
version = models.CharField(max_length=20,blank=True,db_column='version')
target_date = models.DateTimeField(null=True,blank=True,db_column='target_date')
actual_date = models.DateTimeField(null=True,blank=True,db_column='actual_date')
description = models.TextField(db_column='description')
...and a form definition:
class ReleaseStreamForm(ModelForm):
class Meta:
model = ReleaseStream
When the form comes up, I can fill in a value for the "target_date", and not for the "actual_date" fields, and when the form.save() fires it appears to write the value supplied for "target_date" into both fields. I have looked at the post data going into the code that does the form.save() and it definitely has a value for "target_date" and a '' for "actual_date", so I don't think that there is something weird with the form itself, variable names in the POST, etc.
Now, if I supply a non-blank value for "actual_date", the form.save() does the right thing - both the "target_date" and "actual_date" have the correct values written in. Am I doing something wrong, or is this potentially a bug in django?
Here is the template (sorry for the blank comment below:)
{% extends "base.html" %}
{% block title %}{{ form_title }}{% endblock %}
{% block subtitle %}{% endblock %}
{% block content %}
<form action={{ action_url }} method="post">
<table>
{{ form.as_table }}
</table>
<input type="submit" value="Submit" />
</form>
{% endblock %}
And the code that handles the form:
def edit_release_stream(request,req_release_stream_id=None):
form_title = 'Edit release stream'
if request.method == 'POST':
if req_release_stream_id!=None:
release_stream_entry=ReleaseStream.objects.get(pk=req_release_stream_id)
form = ReleaseStreamForm(request.POST,instance=release_stream_entry)
else:
form = ReleaseStreamForm(request.POST)
if form.is_valid():
form.save()
return HttpResponseRedirect('/releases/')
elif req_release_stream_id!=None:
release_stream_entry=ReleaseStream.objects.get(pk=req_release_stream_id)
form = ReleaseStreamForm(instance=release_stream_entry)
else:
form_title = 'Add new release stream'
form = ReleaseStreamForm()
return render_to_response('dashboard/tableform.html', {
'action_url': request.get_full_path(),
'form_title': form_title,
'form': form,
})
... And the post data coming in:
<QueryDict: {u'name': [u'NewRelease'], u'target_date': [u'2011-06-15 00:00'], u'version': [u'4.5.1'], u'actual_date': [u''], u'description': [u'']}>
You can see that it has a valid POST var of "actual_date", with an empty string. This post yields a form.save() that stores the string provided above for "target_date" for both "target_date" and "actual_date".
If I then run a post with differing values for the two dates - here is the post:
<QueryDict: {u'name': [u'NewRelease'], u'target_date': [u'2011-06-15 00:00'], u'version': [u'4.5.1'], u'actual_date': [u'2011-07-15 00:00'], u'description': [u'']}>
In this case, with two distinct, non-empty strings, it writes the correct value shown in the POST above into each of the fields in the db.
I don't believe it to be a bug in Django, or somebody would have seen this problem a long time ago. Can you show us the template that renders the form? Also, if you can show the contents of the request.POST, that'd also be useful.
I'm guessing that your template code is incorrect somehow. The only other problem I can think of would be custom validation in your form (if there is any). Is that the whole ModelForm definition that you've supplied?

Django templates: verbose version of a choice

I have a model:
from django.db import models
CHOICES = (
('s', 'Glorious spam'),
('e', 'Fabulous eggs'),
)
class MealOrder(models.Model):
meal = models.CharField(max_length=8, choices=CHOICES)
I have a form:
from django.forms import ModelForm
class MealOrderForm(ModelForm):
class Meta:
model = MealOrder
And I want to use formtools.preview. The default template prints the short version of the choice ('e' instead of 'Fabulous eggs'), becuase it uses
{% for field in form %}
<tr>
<th>{{ field.label }}:</th>
<td>{{ field.data }}</td>
</tr>
{% endfor %}.
I'd like a template as general as the mentioned, but printing 'Fabulous eggs' instead.
[as I had doubts where's the real question, I bolded it for all of us :)]
I know how to get the verbose version of a choice in a way that is itself ugly:
{{ form.meal.field.choices.1.1 }}
The real pain is I need to get the selected choice, and the only way coming to my mind is iterating through choices and checking {% ifequals currentChoice.0 choiceField.data %}, which is even uglier.
Can it be done easily? Or it needs some template-tag programming? Shouldn't that be available in django already?
In Django templates you can use the "get_FOO_display()" method, that will return the readable alias for the field, where 'FOO' is the name of the field.
Note: in case the standard FormPreview templates are not using it, then you can always provide your own templates for that form, which will contain something like {{ form.get_meal_display }}.
The best solution for your problem is to use helper functions.
If the choices are stored in the variable CHOICES and the model field storing the selected choice is 'choices' then you can directly use
{{ x.get_choices_display }}
in your template. Here, x is the model instance.
Hope it helps.
My apologies if this answer is redundant with any listed above, but it appears this one hasn't been offered yet, and it seems fairly clean. Here's how I've solved this:
from django.db import models
class Scoop(models.Model):
FLAVOR_CHOICES = [
('c', 'Chocolate'),
('v', 'Vanilla'),
]
flavor = models.CharField(choices=FLAVOR_CHOICES)
def flavor_verbose(self):
return dict(Scoop.FLAVOR_CHOCIES)[self.flavor]
My view passes a Scoop to the template (note: not Scoop.values()), and the template contains:
{{ scoop.flavor_verbose }}
Basing on Noah's reply, here's a version immune to fields without choices:
#annoyances/templatetags/data_verbose.py
from django import template
register = template.Library()
#register.filter
def data_verbose(boundField):
"""
Returns field's data or it's verbose version
for a field with choices defined.
Usage::
{% load data_verbose %}
{{form.some_field|data_verbose}}
"""
data = boundField.data
field = boundField.field
return hasattr(field, 'choices') and dict(field.choices).get(data,'') or data
I'm not sure wether it's ok to use a filter for such purpose. If anybody has a better solution, I'll be glad to see it :) Thank you Noah!
We can extend the filter solution by Noah to be more universal in dealing with data and field types:
<table>
{% for item in query %}
<tr>
{% for field in fields %}
<td>{{item|human_readable:field}}</td>
{% endfor %}
</tr>
{% endfor %}
</table>
Here's the code:
#app_name/templatetags/custom_tags.py
def human_readable(value, arg):
if hasattr(value, 'get_' + str(arg) + '_display'):
return getattr(value, 'get_%s_display' % arg)()
elif hasattr(value, str(arg)):
if callable(getattr(value, str(arg))):
return getattr(value, arg)()
else:
return getattr(value, arg)
else:
try:
return value[arg]
except KeyError:
return settings.TEMPLATE_STRING_IF_INVALID
register.filter('human_readable', human_readable)
I don't think there's any built-in way to do that. A filter might do the trick, though:
#register.filter(name='display')
def display_value(bf):
"""Returns the display value of a BoundField"""
return dict(bf.field.choices).get(bf.data, '')
Then you can do:
{% for field in form %}
<tr>
<th>{{ field.label }}:</th>
<td>{{ field.data|display }}</td>
</tr>
{% endfor %}
You have Model.get_FOO_display() where FOO is the name of the field that has choices.
In your template do this :
{{ scoop.get_flavor_display }}
Add to your models.py one simple function:
def get_display(key, list):
d = dict(list)
if key in d:
return d[key]
return None
Now, you can get verbose value of choice fields like that:
class MealOrder(models.Model):
meal = models.CharField(max_length=8, choices=CHOICES)
def meal_verbose(self):
return get_display(self.meal, CHOICES)
Upd.: I'm not sure, is that solution “pythonic” and “django-way” enough or not, but it works. :)
The extended-extended version of Noah's and Ivan's solution. Also fixed Noah's solution for Django 3.1, as ModelChoiceIteratorValue is now unhashable.
#register.filter
def display_value(value: Any, arg: str = None) -> str:
"""Returns the display value of a BoundField or other form fields"""
if not arg: # attempt to auto-parse
# Returning regular field's value
if not hasattr(value.field, 'choices'): return value.value()
# Display select value for BoundField / Multiselect field
# This is used to get_..._display() for a read-only form-field
# which is not rendered as Input, but instead as text
return list(value.field.choices)[value.value()][1]
# usage: {{ field|display_value:<arg> }}
if hasattr(value, 'get_' + str(arg) + '_display'):
return getattr(value, 'get_%s_display' % arg)()
elif hasattr(value, str(arg)):
if callable(getattr(value, str(arg))):
return getattr(value, arg)()
return getattr(value, arg)
return value.get(arg) or ''
<select class="form-select">
{% for key, value in form.meal.field.choices %}
{% if form.meal.value == key %}
<option value="{{ form.key }}" selected>{{ value }}</option>
{% else %}
<option value="{{ key }}">{{ value }}</option>
{% endif %}
{% endfor %}
</select>
Hey what about that way?
in models.py
class MealOrder(models.Model):
CHOICES = (
('s', 'Glorious spam'),
('e', 'Fabulous eggs'),
)
meal = models.CharField(max_length=8, choices=CHOICES)
meal_value = models.CharField(max_length=1, blank=True, null=True,
editable=False)
def save(self, *args, **kwargs):
if self.meal == "s":
self.meal_value = "Glorious spam"
elif self.meal == "e":
self.meal_value = "Fabulous eggs"
super(MealOrder, self).save(*args, **kwargs)
in views.py
from .models import MealOrder
def meal_order(request):
meals = MealOrder.objects.all()
return render(request, "meals.html", {
"meals": meals,
})
in meals.html
{% for meal in meals %}
{{meal.meal_value }}
{%endfor%}