This is my Django app name SFC
This is its models.py:
from django.db import models
import time
color = (
('1','果盤'),
('3','港灣'),
('5','輕快感'),
('6','鵝卵石'),
('7','調味料'),
('8','農收'),
('9','開瓶'),
('10','潛水'),
)
# The Chinese in the tuple name color is a noun describe the color.
# Create your models here.
class class_site(models.Model):
school_name = models.CharField("學校英文縮寫",max_length=10,default='CKJH')
Class = models.CharField("班級",max_length=5,default='802')
page_name = models.CharField("網頁名稱",max_length=10,default='八我啊二班')
color = models.CharField('配色',max_length=8,choices=color,default="6")
logo = models.ImageField('網站logo',null=True)
def __str__(self):
return self.school_name+self.Class+self.page_name
and it's another app name WT
This is its models.py:
from django.db import models
from SFC.models import class_site
# Create your models here.
for i in class_site.objects.all():
code=f'''class {i.school_name + i.Class}subject(models.Model):
subject = models.CharField('科目名',max_length=10)
class {i.school_name + i.Class}WorkType(models.Model):
subject = models.ForeignKey({i.school_name + i.Class}subject , on_delete=models.CASCADE)
work_name = models.CharField('功課名稱',max_length=10,default='習作')
common_name = models.CharField('功課俗名',max_length=10,default='國習')
class {i.school_name + i.Class}ExamType(models.Model):
subject = models.ForeignKey({i.school_name + i.Class}subject , on_delete=models.CASCADE)
work_name = models.CharField('考試名稱',max_length=10,default='大卷')
common_name = models.CharField('功課俗名',max_length=10,default='國卷')
'''
exec(code)
It send me:
class CKJH802WorkType(models.Model):
^
IndentationError: unindent does not match any outer indentation level
I tried not to use f string but i tkink it may be work by using f string.
What's wrong with models.py of WT?
The reason I don't use the foreignkey is because the site is for other people to use, It may cause some mistake.
This is website for education and everyone can ask for create his own class website, it will creates a new class website for him. It can lets the person in charge of the class enter the homework daily.If someone makes the mistake , it would influences the website for other class.
Use textwrap.dedent(text) to handle the indentation from the left side.
Your code:
code=f'''class {i.school_name + i.Class}subject(models.Model):
subject = models.CharField('科目名',max_length=10)
class {i.school_name + i.Class}WorkType(models.Model):
subject = models.ForeignKey({i.school_name + i.Class}subj
is basically this:
class ...:
subject = ...
class ...:
subject = ...
which is causing the indentation error and should look like this:
code=f'''
class {i.school_name + i.Class}subject(models.Model):
subject = models.CharField('科目名',max_length=10)
class {i.school_name + i.Class}WorkType(models.Model):
subject = models.ForeignKey({i.school_name + i.Class}subj
or:
code=f'''\ # to skip the initial empty first line
class {i.school_name + i.Class}subject(models.Model):
subject = models.CharField('科目名',max_length=10)
class {i.school_name + i.Class}WorkType(models.Model):
subject = models.ForeignKey({i.school_name + i.Class}subj
Also, if you really need to solve it this way, try to use metaclasses instead of the combination of exec() + F-strings as it just asks for an exploitation or a nasty bug. Otherwise, just try to use foreign keys or other, saner approach to DB structure + ORM.
Related
I have models:
class Publisher(Model):
name = TextField()
class Author(Model):
name = TextField()
class Book(Model):
publisher = ForeignKey("Publisher")
author = ForeignKey("Author")
class Magazine(Model):
publisher = ForeignKey("Publisher")
writer = ForeignKey("Author")
I want to know which authors wrote for publishers. My version is this:
from django.db.models import TextField, F, Subquery, OuterRef
from django.contrib.postgres.aggregates import StringAgg # I use postgres
# to lead to the same name
books = Book.objects.annotate(author_name=F("author__name"))
magazines = Magazine.objects.annotate(author_name=F("writer__name"))
books = books.values("publisher_id", "author_name")
magazines = magazines.values("publisher_id", "author_name")
product = books.union(magazines)
# !! here I have a problem with grouping
product = product.group_by(
"publisher_id"
).annonate(
author_names=StringAgg("author_name", ";")
)
publishers = Publisher.objects.all().annotate(
author_names=Subquery(
product.filter(publisher_id=OuterRef("id")).values("author_names")[:1],
output_field=TextField()
)
)
# I was expecting something like
# name | author_names
# ------------------------------------------
# Publisher1 | Author1;Author2;Author3
# Publisher2 | Author2
# Publisher3 | Author2;Author3
The problem is that QuerySet has no .group_by() method, instead the .values() method is suggested (product.values("publisher_id").annonate(...)).
But this is complicated by the fact that I had previously called .values("publisher_id", "author_name") to bring two different models into the same view.
I also tried using .only("publisher_id", "author_name"), but (maybe it's a Django bug) this method can't work together with annotated and normal fields.
Is there any way to fix this problem or some other way to get a list of authors for a publisher?
I'm building a simple recipe storage application that uses the Graphene package for GraphQL. I've been able to use Django Forms so far very easily in my mutations, however one of my models fields is really an Enum and I'd like to expose it in Graphene/GraphQL as such.
My enum:
class Unit(Enum):
# Volume
TEASPOON = "teaspoon"
TABLESPOON = "tablespoon"
FLUID_OUNCE = "fl oz"
CUP = "cup"
US_PINT = "us pint"
IMPERIAL_PINT = "imperial pint"
US_QUART = "us quart"
IMPERIAL_QUART = "imperial quart"
US_GALLON = "us gallon"
IMPERIAL_GALLON = "imperial gallon"
MILLILITER = "milliliter"
LITER = "liter"
# Mass and Weight
POUND = "pound"
OUNCE = "ounce"
MILLIGRAM = "milligram"
GRAM = "gram"
KILOGRAM = "kilogram"
My Model:
class RecipeIngredient(TimeStampedModel):
recipe = models.ForeignKey(Recipe, on_delete=models.CASCADE, related_name='ingredients')
direction = models.ForeignKey(RecipeDirection, on_delete=models.CASCADE, null=True, related_name='ingredients')
quantity = models.DecimalField(decimal_places=2, max_digits=10)
unit = models.TextField(choices=Unit.as_tuple_list())
My form:
class RecipeIngredientForm(forms.ModelForm):
class Meta:
model = RecipeIngredient
fields = (
'recipe',
'direction',
'quantity',
'unit',
)
My Mutation:
class CreateRecipeIngredientMutation(DjangoModelFormMutation):
class Meta:
form_class = RecipeIngredientForm
exclude_fields = ('id',)
I've created this graphene enum UnitEnum = Enum.from_enum(Unit) however I haven't been able to get graphene to pick it up. I've tried adding it to the CreateRecipeIngredientMutation as a regular field like unit = UnitEnum() as well as an Input class on that mutation. So far, the closest I've gotten is this Github issue from awhile ago. After playing around with the class in an iPython shell, I think I could just do CreateRecipeIngredientMutation.Input.unit.type.of_type = UnitEnum() but this feels awful.
I came up with a solution that works but is not pretty. I used the https://github.com/hzdg/django-enumfields package to help with this.
I created my own form field:
class EnumChoiceField(enumfields.forms.EnumChoiceField):
def __init__(self, enum, *, coerce=lambda val: val, empty_value='', **kwargs):
if isinstance(enum, six.string_types):
self.enum = import_string(enum)
else:
self.enum = enum
super().__init__(coerce=coerce, empty_value=empty_value, **kwargs)
And used it in my Django form. Then in my custom AppConfig I did this:
class CoreAppConfig(AppConfig):
name = 'myapp.core'
def ready(self):
registry = get_global_registry()
#convert_form_field.register(EnumChoiceField)
def convert_form_field_to_enum(field: EnumChoiceField):
converted = registry.get_converted_field(field.enum)
if converted is None:
raise ImproperlyConfigured("Enum %r is not registered." % field.enum)
return converted(description=field.help_text, required=field.required)
And finally in my schema:
UnitEnum = Enum.from_enum(Unit)
get_global_registry().register_converted_field(Unit, UnitEnum)
I really don't like this, but couldn't think of a better way to handle this. I came across this idea when searching down another graphene django issue here https://github.com/graphql-python/graphene-django/issues/481#issuecomment-412227036.
I feel like there has to be a better way to do this.
I am trying to display data from several models that are related together through a QuerySet. My ultimate goal is to display some information from the Site model, and some information from the Ppack model, based on a date range filter of the sw_delivery_date in the Site model.
Here are my models:
class Site(models.Model):
mnemonic = models.CharField(max_length = 5)
site_name = models.CharField(max_length = 100)
assigned_tech = models.ForeignKey('Person', on_delete=models.CASCADE, null = True, blank = True)
hw_handoff_date = models.DateField(null = True, blank = True)
sw_delivery_date = models.DateField(null = True, blank = True)
go_live_date = models.DateField(null = True, blank = True)
web_url = models.CharField(max_length = 100, null = True, blank = True)
idp_url = models.CharField(max_length = 100, null = True, blank = True)
def __str__(self):
return '(' + self.mnemonic + ') ' + self.site_name
class Ring(models.Model):
ring = models.IntegerField()
def __str__(self):
return "6." + str(self.ring)
class Ppack(models.Model):
ppack = models.IntegerField()
ring = models.ForeignKey('Ring', on_delete=models.CASCADE)
def __str__(self):
return str(self.ring) + " pp" + str(self.ppack)
class Code_Release(models.Model):
Inhouse = 'I'
Test = 'T'
Live = 'L'
Ring_Location_Choices = (
(Inhouse, 'Inhouse'),
(Test, 'Test'),
(Live, 'Live'),
)
site_id = models.ForeignKey('Site', on_delete=models.CASCADE)
type = models.CharField(max_length = 1, choices = Ring_Location_Choices, blank = True, null = True)
release = models.ForeignKey('Ppack', on_delete=models.CASCADE)
def __str__(self):
return "site:" + str(self.site_id) + ", " + self.type + " = " + str(self.release)
If I use the following,
today = datetime.date.today()
future = datetime.timedelta(days=60)
new_deliveries = Site.objects.select_related().filter(sw_delivery_date__range=[today, (today + future)])
I can get all of the objects in the Site model that meet my criteria, however, because there is no relation from Site to Code_Release (there's a one-to-many coming the other way), I can't get at the Code_Release data.
If I run a for loop, I can iterate through every Site returned from the above query, and select the data from the Code_Release model, which allows me to get the related data from the Ppack and Ring models.
site_itl = {}
itl = {}
for delivery in new_deliveries:
releases = Code_Release.objects.select_related().filter(site_id = delivery.id)
for rel in releases:
itl[rel.id] = rel.release
site_itl[delivery.id] = itl
But, that seems overly complex to me, with multiple database hits and possibly a difficult time parsing through that in the template.
Based on that, I was thinking that I needed to select from the Code_Release model. That relates back to both the Site model and the Ppack model (which relates to the Ring model). I've struggled to make the right query / access the data in this way that accomplishes what I want, but I feel this is the right way to go.
How would I best accomplish this?
You can use RelatedManager here. When you declare ForeignKey, Django allows you to access reverse relationship. To be specific, let's say that you have multiple code releases that are pointing to one specific site. You can access them all via site object by using <your_model_name_lowercase>_set attribute. So in your case:
site.code_release_set.all()
will return QuerySet of all code release objects that have ForeignKey to object site
You can access the Releases from a Site object. First, you can put a related_name to have a friendly name of the reverse relation between the models:
site_id = models.ForeignKey('Site', on_delete=models.CASCADE, related_name="releases")
and then, from a Site object you can make normal queries to Release model:
site.releases.all()
site.releases.filter(...)
...
I'm in the process of creating an assessment system using Django; however, I have an integrated test that passes and I'm not sure as to why (it should be failing). In the test, I set the grade field of the bobenrollment object to "Excellent". As you can see from the models below, the Enrollment model doesn't have a grade field (none of the models do). I was under the impression that dot notation of model objects would access the model fields (I'm probably incorrect about this). I don't want to write ineffective tests, so I would like to know what makes this test pass and what I should do to make it break. Thanks!
class ClassAndSemesterModelTest(TestCase):
def add_two_classes_to_semester_add_two_students_to_class(self):
first_semester = Semester.objects.create(text='201530')
edClass = EdClasses.objects.create(name='EG 5000')
edClass2 = EdClasses.objects.create(name='EG 6000')
first_semester.classes.add(edClass)
first_semester.classes.add(edClass2)
bob = Student.objects.create(name="Bob DaBuilder")
jane = Student.objects.create(name="Jane Doe")
bobenrollment = Enrollment.objects.create(student=bob, edclass=edClass)
janeenrollment = Enrollment.objects.create(student=jane,edclass=edClass)
bobenrollment2 = Enrollment.objects.create(student=bob,edclass=edClass2)
janeenrollment2 = Enrollment.objects.create(student=jane,edclass=edClass2)
def test_students_link_to_enrollments(self):
self.add_two_classes_to_semester_add_two_students_to_class()
edclass1 = EdClasses.objects.get(name="EG 5000")
bob = Student.objects.get(name="Bob DaBuilder")
#The three lines below are the subject of my question
bobenrollment = Enrollment.objects.get(edclass=edclass1, student=bob)
bobenrollment.grade = "Excellent"
self.assertEqual(bobenrollment.grade, "Excellent")
And the models below:
from django.db import models
class Student(models.Model):
name = models.TextField(default="")
def __str__(self):
return self.name
#TODO add models
class EdClasses(models.Model):
name = models.TextField(default='')
students = models.ManyToManyField(Student, through="Enrollment")
def __str__(self):
return self.name
class Semester(models.Model):
text = models.TextField(default='201530')
classes = models.ManyToManyField(EdClasses)
def __str__(self):
return self.text
class Enrollment(models.Model):
student = models.ForeignKey(Student)
edclass = models.ForeignKey(EdClasses)
Requirements.txt
beautifulsoup4==4.4.1
Django==1.5.4
ipython==3.1.0
LiveWires==2.0
nose==1.3.3
Pillow==2.7.0
projectname==0.1
pyperclip==1.5.11
pytz==2015.2
requests==2.10.0
selenium==2.53.6
six==1.9.0
South==1.0.2
swampy==2.1.7
virtualenv==1.11.5
I was under the impression that dot notation of model objects would access the model fields (I'm probably incorrect about this)
You're correct about this. What you're not taking into account is the fact that you can dynamically add properties to python objects. For instance:
In [1]: class MyClass():
...: pass
...:
In [2]: a = MyClass()
In [3]: a.im_a_property = 'hello'
In [4]: print a.im_a_property
hello
As you can see, the a instance will have the im_a_propery property even though it's not defined by the class. The same applies for the following line in your code:
bobenrollment.grade = "Excellent"
Django models override this behavior so you can seamlessly get DB values as properties of your model instance, but the instance is just a regular python object.
If you want to test the grade property gets saved correctly, you should modify your test to add the value of grade when creating the record and making sure the instance you assert against is the one you read from your DB (i.e. not modifying it beforehand).
I'm trying to use factory_boy to help generate some MongoEngine documents for my tests. I'm having trouble defining EmbeddedDocumentField objects.
Here's my MongoEngine Document:
class Comment(EmbeddedDocument):
content = StringField()
name = StringField(max_length=120)
class Post(Document):
title = StringField(required=True)
tags = ListField(StringField(), required=True)
comments = ListField(EmbeddedDocumentField(Comment))
Here's my partially completed factory_boy Factory:
class CommentFactory(factory.Factory):
FACTORY_FOR = Comment
content = "Platinum coins worth a trillion dollars are great"
name = "John Doe"
class BlogFactory(factory.Factory):
FACTORY_FOR = Blog
title = "On Using MongoEngine with factory_boy"
tags = ['python', 'mongoengine', 'factory-boy', 'django']
comments = [factory.SubFactory(CommentFactory)] # this doesn't work
Any ideas how to specify the comments field? The problem is that factory-boy attempts to create the Comment EmbeddedDocument.
I'm not sure if this is what you want but I just started looking at this problem and this seems to work:
from mongoengine import EmbeddedDocument, Document, StringField, ListField, EmbeddedDocumentField
import factory
class Comment(EmbeddedDocument):
content = StringField()
name = StringField(max_length=120)
class Post(Document):
title = StringField(required=True)
tags = ListField(StringField(), required=True)
comments = ListField(EmbeddedDocumentField(Comment))
class CommentFactory(factory.Factory):
FACTORY_FOR = Comment
content = "Platinum coins worth a trillion dollars are great"
name = "John Doe"
class PostFactory(factory.Factory):
FACTORY_FOR = Post
title = "On Using MongoEngine with factory_boy"
tags = ['python', 'mongoengine', 'factory-boy', 'django']
comments = factory.LazyAttribute(lambda a: [CommentFactory()])
>>> b = PostFactory()
>>> b.comments[0].content
'Platinum coins worth a trillion dollars are great'
I wouldn't be surprised if I'm missing something though.
The way that I'm doing it right now is to prevent the Factories based on EmbeddedDocuments from building. So, I've setup up an EmbeddedDocumentFactory, like so:
class EmbeddedDocumentFactory(factory.Factory):
ABSTRACT_FACTORY = True
#classmethod
def _prepare(cls, create, **kwargs):
return super(EmbeddedDocumentFactory, cls)._prepare(False, **kwargs)
Then I inherit from that to create factories for EmbeddedDocuments:
class CommentFactory(EmbeddedDocumentFactory):
FACTORY_FOR = Comment
content = "Platinum coins worth a trillion dollars are great"
name = "John Doe"
This may not be the best solution, so I'll wait on someone else to respond before accepting this as the answer.