I have a problem in obtaining a single id from a queryset. I post my models and views in order to be more clear:
models.py
class MissionEntry(models.Model):
student = models.ForeignKey(
Student, on_delete=models.DO_NOTHING, blank=True, null=True)
mission = models.ForeignKey(
Mission, on_delete=models.DO_NOTHING, null=True, blank=True)
log_entry = models.ForeignKey(
LogEntry, on_delete=models.DO_NOTHING, blank=True, null=True)
learning_objective = models.ForeignKey(
LearningObjective, on_delete=models.DO_NOTHING, blank=True, null=True)
grade = models.CharField(
max_length=10, choices=GRADING_VALUE, blank=True, null=True)
note = models.TextField(blank=True, null=True)
debriefing = models.TextField(blank=True, null=True)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
def __str__(self):
return str(self.mission) + ' ' + str(self.log_entry)
class Meta:
verbose_name_plural = 'Mission Entries'
class MissionEntryStatus(models.Model):
mission = models.ForeignKey(
Mission, on_delete=models.PROTECT, null=True, blank=True)
student = models.ForeignKey(Student, on_delete=models.PROTECT)
is_completed = models.BooleanField(default=False)
is_failed = models.BooleanField(default=False)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
class StudentMission(models.Model):
mission = models.ForeignKey(Mission, on_delete=models.PROTECT)
student_training_course = models.ForeignKey(
StudentTrainingCourse, on_delete=models.PROTECT)
mission_status = models.ForeignKey(
MissionEntryStatus, on_delete=models.PROTECT, blank=True, null=True)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
class Meta:
ordering = ['mission__name']
def __str__(self):
return self.mission.name
class LogEntry(models.Model):
aircraft = models.ForeignKey(Aircraft, on_delete=models.DO_NOTHING)
adep = models.ForeignKey(
Aerodrome, on_delete=models.PROTECT, related_name='adep')
ades = models.ForeignKey(
Aerodrome, on_delete=models.PROTECT, related_name='ades')
date = models.DateField()
etd = models.TimeField()
ata = models.TimeField()
eet = models.TimeField()
function_type = models.ForeignKey(FunctionType, on_delete=models.PROTECT)
student = models.ForeignKey(
Student, on_delete=models.PROTECT, blank=True, null=True)
instructor = models.ForeignKey(
Instructor, on_delete=models.PROTECT, blank=True, null=True)
student_mission = models.ForeignKey(
'mission.StudentMission', on_delete=models.PROTECT, null=True, blank=True)
note = models.TextField(null=True, blank=True)
cross_country = models.BooleanField(default=False)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
views.py
def student_mission_list(request, pk):
student = Student.objects.get(id=pk)
student_training_course = StudentTrainingCourse.objects.filter(
student_id=student.id)
missions = StudentMission.objects.filter(
student_training_course_id__in=student_training_course)
mission_entry = MissionEntry.objects.filter(student_id=student)
log_entry = LogEntry.objects.filter(student_mission_id__in=missions)
print(log_entry)
context = {
'student': student,
'missions': missions,
'mission_entry': mission_entry,
}
return render(request, 'mission/student_mission_list.html', context)
In fact, what I need to do, is to obtain a single value for the log_entry. The problem is that, obviously, I am retrieving multiple values of log_entry. But I would like to get the single pk of the log_entry.
Any suggestion? Should I remodel the models.py file?
try this:
log_entry = LogEntry.objects.get(student_mission_id__in=missions)
print(log_entry.id)
Related
I have to serialize spare instance from spare variety many to many field.
Models.py
class SpareVariety(models.Model):
quality = models.ForeignKey(Quality, max_length=255, on_delete=models.CASCADE, null=True, blank=True)
variety_name = models.CharField(max_length=255, null=True, blank=True)
property = models.ForeignKey(SpareProperty, null=True, blank=True, on_delete=models.CASCADE)
purchase_price = models.PositiveIntegerField(help_text="in INR", blank=True, null=True)
retail_price = models.FloatField(help_text="All values in INR", blank=True, null=True)
dealer_price = models.FloatField(help_text="All values in INR", blank=True, null=True)
stock_available = models.PositiveIntegerField(blank=True, null=True,default=True)
spare_costing = models.ForeignKey(SpareCosting, on_delete=models.CASCADE, blank=True, null=True)
spare_discount = models.ForeignKey(Discount, on_delete=models.CASCADE, blank=True, null=True)
is_available = models.BooleanField(default=False)
date_added = models.DateTimeField(auto_now=True)
date_updated = models.DateTimeField(auto_now_add=True)
class Spare(models.Model):
product = models.ForeignKey(Product, on_delete=models.CASCADE)
spare_variety = models.ManyToManyField(SpareVariety, related_name='spare_varieties', null=True, blank=True)
name = models.CharField(max_length=255, help_text="Enter the name of spare (Ex:Display, Speakers)")
type = models.ForeignKey(Type, blank=True, null=True, on_delete=models.CASCADE)
date_added = models.DateTimeField(auto_now=True)
date_updated = models.DateTimeField(auto_now_add=True)
def __str__(self):
return '%s - %s' % (self.product.name, self.name)
Serialize the spare model from spare variety serializer
serializers.py
class SpareVarietySerializer(serializers.HyperlinkedModelSerializer):
spare_costing= SpareCostingSerializer(many=False, read_only=False)
spare_discount = DiscountSerializer(many=False, read_only=False)
quality = QualitySerializer(many=False, read_only=False)
property = SparePropertySerializer(many=False, read_only=False)
spare_name = serializers.CharField(read_only=True, source="spare.name")
class Meta:
model = SpareVariety
fields = ['id','quality','variety_name','purchase_price','spare_name','retail_price','property', 'dealer_price', 'stock_available','spare_costing','spare_discount','is_available', 'date_added', 'date_updated',]
I have a quiz application made with Django. I am basically loading a pretty complex query. What I am basically doing is creating a new exam with this logic:
Fetch the question from the question bank (the Question model)
I get a certain questions number from each subject and I use them to create a QuestionDraft so I can store and save each student result.
Each QuestionDraft has the AnswerDraft which I use for storing the user answered questions (each AnswerDraft is basically a carbon copy of the question bank Answer).
While I wanna load a 50-question-test everything works pretty fine but when I want to load more than that amount of question, the page is loading extremely slow.
I would like to know if, based on the models and the code I post down below, there is any way to improve the efficiency of the queries and/or the loading time.
models.py
class QuestionSubject(models.Model):
quiz_course = models.ForeignKey(QuizTheoryCourse, on_delete=models.CASCADE)
name = models.CharField(max_length=200)
exam_questions_num = models.IntegerField(null=True, blank=True)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
class Question(models.Model):
id = models.CharField(max_length=7,
default=generate_question_id,
unique=True,
primary_key=True,
editable=False)
question_subject = models.ForeignKey(
QuestionSubject, on_delete=models.CASCADE)
text = models.TextField()
mark = models.IntegerField(default=1)
is_published = models.BooleanField(default=True)
question_bank_id = models.CharField(max_length=255, blank=True, null=True)
question_topic = models.ForeignKey(
QuestionTopic, on_delete=models.CASCADE, null=True, blank=True)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
class Answer(models.Model):
question = models.ForeignKey(Question, on_delete=models.CASCADE)
text = models.TextField()
is_correct = models.BooleanField(default=False)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
class QuizProfile(models.Model):
id = models.CharField(max_length=7,
default=generate_question_id,
unique=True,
primary_key=True,
editable=False)
user = models.ForeignKey(CustomUser, on_delete=models.CASCADE)
subject = models.ForeignKey(
QuestionSubject, on_delete=models.CASCADE, blank=True, null=True)
total_score = models.DecimalField(default=0,
decimal_places=2,
max_digits=5)
quiz_type = models.CharField(
max_length=255, choices=quiz_type, blank=True, null=True)
right_answer = models.IntegerField(default=0)
is_completed = models.BooleanField(default=False)
is_assigned = models.BooleanField(blank=True, null=True, default=False)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
def __str__(self):
return self.user.username + ' ' + self.id
class Meta:
ordering = ('-created_at',)
class QuestionDraft(models.Model):
quiz_profile = models.ForeignKey(QuizProfile,
on_delete=models.CASCADE,
blank=True,
null=True)
question = models.ForeignKey(Question,
on_delete=models.CASCADE,
blank=True,
null=True)
text = models.TextField()
is_answered = models.BooleanField(blank=True, null=True)
is_correct = models.BooleanField(blank=True, null=True)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
def __str__(self):
return str(self.quiz_profile) + ' ' + str(self.question)
class AnswerDraft(models.Model):
quiz_profile = models.ForeignKey(QuizProfile,
on_delete=models.CASCADE,
blank=True,
null=True)
question_draft = models.ForeignKey(QuestionDraft, on_delete=models.CASCADE)
answer = models.ForeignKey(Answer,
on_delete=models.CASCADE,
null=True,
blank=True)
text = models.TextField()
is_answered = models.BooleanField(blank=True, null=True)
is_correct = models.BooleanField(default=False)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
def __str__(self):
return str(self.quiz_profile) + ' ' + str(self.answer)
class QuizDraft(models.Model):
id = models.CharField(max_length=7,
default=generate_question_id,
unique=True,
primary_key=True,
editable=False)
quiz_profile = models.ForeignKey(QuizProfile, on_delete=models.CASCADE)
question_draft = models.ForeignKey(QuestionDraft,
on_delete=models.CASCADE,
blank=True,
null=True)
def __str__(self):
return str(self.quiz_profile)
views.py
def ppl_exam_generator_util(request, subjects):
question_list = [Question.objects.filter(question_subject=subject).order_by(
'?')[:int(subject.exam_questions_num)]for subject in subjects]
quiz_profile = QuizProfile(
user=request.user, quiz_type='ppl_exam')
quiz_profile.save()
for ques in question_list:
for q in ques:
question = Question.objects.get(id=q.id)
quiz_attempt = QuizAttempt(quiz_profile=quiz_profile,
question=question)
quiz_attempt.save()
question_draft = QuestionDraft(
question=question, text=question.text, quiz_profile=quiz_profile)
question_draft.save()
quiz_draft = QuizDraft(
quiz_profile=quiz_profile, question_draft=question_draft)
quiz_draft.save()
answers = Answer.objects.filter(question__id=question.id)
shuffle(list(answers))
for ans in answers:
draft_answer = AnswerDraft(
question_draft=question_draft, answer=ans, text=ans.text, quiz_profile=quiz_profile)
draft_answer.save()
return HttpResponseRedirect(reverse('quiz:new_ppl_exam', kwargs={'pk': quiz_profile.id}))
I tried also with the connection.queries tool Django provides, but each query is pretty fast. I don't know if it's a problem with the nested forloop or something else.
I am trying to filter my many to many variation fields with respect to the product. means, I only want the variations related to the current product to show in the admin page. now its showing all the variations available for every product.
I added formfield_for_manytomany() function to my admin.py but how can I get the current product(id) in the cart or order to filter the variations?
most of the questions in stack overflow Is based on the current user, which is easy to get? but how should I get the specific product(id) that is opened in the admin panel.
admin.py
from django.contrib import admin
from .models import *
from products.models import Variation
class CartAdmin(admin.ModelAdmin):
list_display = ('cart_id', 'date_created')
class CartItemAdmin(admin.ModelAdmin):
list_display = ('user','cart', 'product', 'quantity','is_active')
def formfield_for_manytomany(self, db_field, request, **kwargs):
if db_field.name == "variation":
product = Products.objects.get(id='??') # how I get the current product in the cart or order
kwargs["queryset"] = Variation.objects.filter(product=product.id)
return super().formfield_for_manytomany(db_field, request, **kwargs)
admin.site.register(Cart, CartAdmin)
admin.site.register(CartItem, CartItemAdmin)
CartItem Model
class CartItem(models.Model):
user = models.ForeignKey(CustomUser, on_delete=models.CASCADE, null=True)
cart = models.ForeignKey(Cart, on_delete=models.CASCADE, null=True)
product = models.ForeignKey(Products, on_delete=models.CASCADE)
variation = models.ManyToManyField(Variation, blank=True)
quantity = models.IntegerField()
is_active = models.BooleanField(default=True)
created_date = models.DateTimeField(auto_now_add=True)
def item_total(self):
return self.product.price * self.quantity
def __str__(self):
return self.product.name
Product and Variation Model
class Products(models.Model):
name = models.CharField(max_length=50, unique=True)
slug = AutoSlugField(populate_from='name', max_length=100, unique=True)
isbn = models.CharField(max_length=20, unique=True, blank=True, null=True)
sub_category = models.ForeignKey(SubCategory, on_delete=models.CASCADE)
language = models.ForeignKey(Language, on_delete=models.SET_NULL, null=True)
author = models.CharField(max_length=100)
Publisher = models.CharField(max_length=100, blank=True, default=None)
release_date = models.DateField(blank=True, null=True, default=None)
price = models.IntegerField(default=None)
stock = models.IntegerField(default=None)
is_available = models.BooleanField(default=True)
cover_image = models.ImageField(upload_to='images/products')
image1 = models.ImageField(upload_to='images/products', blank=True, default=None, null=True)
image2 = models.ImageField(upload_to='images/products', blank=True, default=None, null=True)
image3 = models.ImageField(upload_to='images/products', blank=True, default=None, null=True)
description = models.TextField(max_length=2000, blank=True, default=None)
create_date = models.DateTimeField(auto_now_add=True)
modified_date = models.DateTimeField(auto_now=True)
number_of_pages = models.IntegerField(blank=True, null=True)
weight = models.IntegerField(blank=True, null=True)
width = models.IntegerField(blank=True, null=True)
height = models.IntegerField(blank=True, null=True)
spine_width = models.IntegerField(blank=True, null=True)
class Meta:
verbose_name = 'Product'
verbose_name_plural = 'Products'
def get_url(self):
return reverse('product-view', args=[self.slug])
def __str__(self):
return self.name
class Variation(models.Model):
product = models.ForeignKey(Products, on_delete=models.CASCADE)
variation_category = models.CharField(max_length=100, choices=variation_category_choice)
variation_value = models.CharField(max_length=100, choices=variation_value_choice)
is_available = models.BooleanField(default=True)
date_added = models.DateTimeField(auto_now_add=True)
objects = VariationManager()
def __str__(self):
return self.variation_value
THe error upon clicking the POST button on Djangorest Form
The serializer:
class CreatePolicyBenefitsSerializer(serializers.ModelSerializer):
class Meta:
model = Policy
fields = ('company','name','benefits','price')
The views:
class CreatePolicyBenefits(CreateAPIView):
queryset = Policy.objects.all()
serializer_class = CreatePolicyBenefitsSerializer
The Policy Model
``
class Policy(TimeStampedModel):
POLICY_CHOICES = (
('life', 'Life'),
('health', 'Health'),
('home', 'Home'),
('car', 'Car'),
('vul', 'VUL'),
)
PREMIUM_INTERVALS = (
('one_time', 'One Time'),
('annual', 'Annual'),
('semi_annual', 'Semi Annual'),
('quarterly', 'Quarterly'),
('monthly', 'Monthly')
)
company = models.ForeignKey(
'Company', related_name='Policies', on_delete=models.CASCADE,
null=True, blank=True)
name = models.CharField(max_length=255, blank=True, null=True, default="")
description = models.TextField(blank=True, null=True, default="")
benefits = models.JSONField(null=True, blank=True)
price = models.DecimalField(max_digits=10, decimal_places=2, default=0)
category = models.CharField(
max_length=64, blank=True, null=True, choices=POLICY_CHOICES, default="")
premium_details = models.CharField(max_length=255, blank=True, null=True)
policy_details = models.CharField(max_length=255, blank=True, null=True)
available_premium_interval = models.CharField(
max_length=64, blank=True, null=True, choices=PREMIUM_INTERVALS)
icon_name = models.CharField(max_length=32, blank=True, null=True)
icon_file = models.FileField(
upload_to=upload_policy_icon, blank=True, null=True)
primary_color = models.CharField(max_length=32, blank=True, null=True)
# file=models.FilePathField(path=os.path.join(settings.MEDIA_ROOT, 'media'))
adminupload=models.FileField(upload_to=pdf_path,max_length=None)
pdfname=models.CharField(max_length=255, blank=True, null=True)
class Meta:
app_label = samplename
def __str__(self):
return '[%s] %s-%s' % (self.id, self.company, self.name)
Here the form
Is it possible when I hit POST button, the data can be displayed on the form? Thanks
I'm using django-filter and I would like to ask you if it could filter one to many reliontionship because I did not found any doc or example even on StackOverflow., here are the model, the filter and the view
class Aliens(models.Model):
class Meta:
db_table = 'aliens'
verbose_name = ('Introduction Event')
verbose_name_plural = ('Introuction Events')
ordering = ['alien']
alien = models.OneToOneField(Taxonomy, verbose_name=u"Non-indigenous Species",
on_delete=models.CASCADE, null=True, blank=True)
#SpeciesName = models.CharField(max_length=100, verbose_name=u"Species Name", blank=True, null=True)
group = models.OneToOneField(Ecofunctional, verbose_name=u"Ecofunctional Group", on_delete=models.CASCADE,
blank=True, null=True, default='')
firstsight = models.IntegerField(('First Mediterranean Sighting'), choices=YEAR_CHOICES, blank=True, null=True)
med_citation = models.ForeignKey(biblio, verbose_name=u"Mediterranean first citation", on_delete=models.CASCADE,
null=True, blank=True)
origin = models.OneToOneField(Origin, on_delete=models.CASCADE, blank=True, null=True, default='',
verbose_name=u"Origin")
status = models.OneToOneField(SuccessType, on_delete=models.CASCADE, blank=True, null=True, default='',
verbose_name=u"Establishement")
created_by = CurrentUserField()
created_at = models.DateField('date of inclusion', blank=True, null=True, default=datetime.datetime.now())
photo = models.ImageField(upload_to='photos', blank=True, null=True)
vector = models.ManyToManyField(vectors, verbose_name=u"Vectors/Pathways")
updated_at = models.DateField('date of updating', blank=True, null=True, default=datetime.datetime.now())
updated_by = models.ForeignKey(User, on_delete=models.CASCADE, related_name='%(class)s_requests_updated',
default=CurrentUserField(), null=True)
notes = models.TextField(verbose_name='Notes', blank=True, null=True)
db_status = StateField(verbose_name='Species Status in the Db', blank=True, null=True)
def __str__(self): # __unicode__ on Python 2
return self.alien.SpeciesName
class Distributions(models.Model):
class Meta:
db_table = 'distributions'
verbose_name = ('verified occurence')
verbose_name_plural = ('verified occurences')
alien = models.ForeignKey(Aliens, verbose_name=u"Non-Indeginous Species", related_name='distributions',
on_delete=models.CASCADE, null=True, blank=True)
country = models.OneToOneField(Country, on_delete=models.CASCADE, verbose_name='Country', blank=True, null=True)
seas = models.OneToOneField(regionalseas, on_delete=models.CASCADE, verbose_name='Regional Sea', blank=True,
null=True)
MSFD = models.OneToOneField(MSFD, on_delete=models.CASCADE, verbose_name='MSFD/EcAp Sub-region', blank=True,
null=True)
area1stSighting = models.DateField('First Areas Sighting', blank=True, null=True, default=datetime.datetime.now())
AreaSuccessType = models.OneToOneField(SuccessType, on_delete=models.CASCADE,
verbose_name='Area Establishement/Success', blank=True, null=True)
Area_citation = models.ForeignKey(biblio, verbose_name=u"Area first citation", on_delete=models.CASCADE, null=True,
blank=True)
created_by = models.ForeignKey(User, on_delete=models.CASCADE, related_name='%(class)s_requests_created',
default='')
created_at = models.DateField('date of Edition', blank=True, null=True, default=datetime.datetime.now())
updated_by = models.ForeignKey(User, on_delete=models.CASCADE, related_name='%(class)s_requests_updated',
default='')
updated_at = models.DateField('date of updating', blank=True, null=True, default=datetime.datetime.now())
notes = models.TextField(verbose_name='Notes', blank=True, null=True)
dverification = StateField(verbose_name='Validated ')
def __str__(self): # __unicode__ on Python 2
return self.alien.SpeciesName
class AliensFilter(django_filters.FilterSet):
country = filters.ModelChoiceFilter(label='Country', queryset=Country.objects.all())
msfd = filters.ModelChoiceFilter(label='MSF/EcAp Subregions', queryset=MSFD.objects.all())
regseas = filters.ModelChoiceFilter(label='Regional Seas', queryset=regionalseas.objects.all())
vector = filters.ModelChoiceFilter(label='Vectors/Pathway', queryset=vectors.objects.all())
Species = filters.ModelChoiceFilter(label='Species Name', queryset=Taxonomy.objects.all())
class Meta:
model = Aliens
fields = (
'Species', 'group', 'origin', 'firstsight', 'status', 'vector', 'country', 'msfd', 'regseas')
def search(request):
Aliens_list = Aliens.objects.all().select_related('origin', 'status', 'group', 'Taxonomy')
aliens_filter = AliensFilter(request.GET, queryset=Aliens_list)
# return render(request, 'mamias/list.html', {'filter': aliens_filter})
return render(request, 'mamias/list2.html', {'filter': aliens_filter})
How could I filter based on country for example?
There is no direct relationship between the Aliean and Country models. You would need to instead filter by country through the distributions relationship.
from django_filters import FilterSet, filters
class AlienFilter(FilterSet):
country = filters.ModelChoiceFilter(
field_name='distributions__country',
queryset=Country.objects.all(),
)