I have this model:
class Task(db.Model):
...
created = db.Column(db.DateTime, index=False, unique=False, nullable=False)
active = db.Column(db.Boolean, index=False, unique=False, default=False)
...
In my Flask endpoint I would like to use order_by first on the created date. And then afterwards based on the active state of the Task. So if active = True it should be sorted on that as well. Is this possible?
I tried this:
#app.route('/tasks', methods=['GET'])
def get_tasks():
all_tasks = Task.query.order_by(Task.created.desc(), Task.active).all()
return jsonify(tasks_schema.dump(all_tasks))
However that is not working. Any ideas?
Maybe not answer to your question, as you want to use order_by, but I'm using this code to order by boolean:
self.items.sort(key=lambda x: (-x.active, x.name))
Related
I am building an admin dashboard for my web app using Flask-Admin. For the user/address relationship, I am using a one to one relationship. On the user edit form, I'd like to be able to edit the individual components of the address (i.e. street address, city or zip) similar to what inline_models provides. Instead, flask-admin generates a select field and only allows me to select a different addresses.
I tried using inline_models = ['address'] in the UserModelView definition. However, I got the address object not iterable error due to the user/address relationship being configured to uselist=False. Switching uselist to True would affect other parts of my code, so I'd prefer to leave it as False.
From looking in flask-admin/contrib/sqla/forms, within the function get_forms, its being assigned a one to many tag which is what drives the use of a select field.
Before diving in further, I figured it best to see if anyone else has come across this or has a recommended fix/workaround.
models.py
class User(db.Model):
id = db.Column(db.Integer, primary_key=True)
username = db.Column(db.String(64))
address = db.relationship("Address", backref="user",
cascade="all, delete-orphan", lazy=False,
uselist=False, passive_deletes=True)
class Address(db.Model):
id = db.Column(db.Integer, primary_key=True)
line1 = db.Column(db.String(128))
zip = db.Column(db.String(20), index=True)
city = db.Column(db.String(64), index=True, nullable=False)
user_id = db.Column(db.Integer, db.ForeignKey("user.id",
ondelete="CASCADE"))
admin.py
class UserModelView(ModelView):
column_list = [User.username, 'address']
form_columns = (User.username, 'address')
admin = Admin(name='Ask', template_mode='bootstrap3')
admin.add_view(UserModelView(User, db.session))
You can create 2 relations
# Relation for flask admin inline model
address_cms_relationsip = db.relationship(
"Address", backref="user", cascade="all, delete-orphan", lazy=False,
uselist=True, passive_deletes=True)
address_relationship = db.relationship(
"Address", cascade="all, delete-orphan", lazy=False,
uselist=False, passive_deletes=True)
#property
def address(self):
return self.address_relationship
In your code you can use property address
user: User # some User object
user.address.city
class Docs(models.Model):
doc_id = models.BigIntegerField(primary_key=True)
journal = models.CharField(max_length=50, blank=True, null=True)
year = models.IntegerField(blank=True, null=True)
class Meta:
managed = False
db_table = 'docs'
class Assays(models.Model):
assay_id = models.BigIntegerField(primary_key=True)
doc = models.ForeignKey('Docs', models.DO_NOTHING)
description = models.CharField(max_length=4000, blank=True, null=True)
class Meta:
managed = False
db_table = 'assays'
class Activities(models.Model):
activity_id = models.BigIntegerField(primary_key=True)
assay = models.ForeignKey(Assays, models.DO_NOTHING)
doc = models.ForeignKey(Docs, models.DO_NOTHING, blank=True, null=True)
record = models.ForeignKey('CompoundRecords', models.DO_NOTHING)
class Meta:
managed = False
db_table = 'activities'
I apologize in advance if this answer is easily found elsewhere. I have searched all over and do not see a simple way to query my data as intuitively as I feel like should be possibe.
These are classes for 3 tables. The actual dataset is closer to 100 tables. Each doc_id can have one or many associated activity_ids. Each activity_id is associated with one assay_id.
My goal is to obtain all of the related data for each of the activities in a single doc. For instance:
query_activities_values = Docs.objects.get(doc_id=5535).activities_set.values()
for y in query_activities_values:
print(y)
break
>>> {'activity_id': 753688, 'assay_id': 158542, 'doc_id': 5535, .....
This returns 32 dictionaries (only part of the first is shown) for columns in the Activities table that have doc_id=5535. I would like to go one step further and also automatically pull in all of the data from the Assays table that is associated with the corresponding assay_id for each dictionary.
I can access that Assay data through a similar query, but only by stating each field explicitly:
query_activities_values = Docs.objects.get(doc_id=5535).activities_set.values('assay', 'assay__assay_type', 'assay__description')
for y in query_activities_values:
print(y)
break
I would like a single query that finds not only the assay and associated assay data for one activity_id, but finds all data and associated data for the 90+ other tables associated in the model
Thank you
Update 1
I did find this code that works surprisingly well for my needs, however, I was curious if this is the best method:
from django.forms.models import model_to_dict
def serial_model(modelobj):
opts = modelobj._meta.fields
modeldict = model_to_dict(modelobj)
for m in opts:
if m.is_relation:
foreignkey = getattr(modelobj, m.name)
if foreignkey:
try:
modeldict[m.name] = serial_model(foreignkey)
except:
pass
return modeldict
That's not too much code, but I thought there may be a more built-in way to do this.
What you need is prefetch_related:
Django 2.2 Prefetch Related Docs
query_activities_values = Docs.objects.get(doc_id=5535).activities_set.values()
Would become:
query_activities_values = Docs.objects.prefetch_related(models.Prefetch("activities_set", to_attr="activities"), models.Prefetch("assays_set", to_attr="assays")).get(doc_id=5535)
A new attributes will be created called "activities" and "assays" which you can use to retrieve data.
One more thing. This isn't actually 1 query. It's 3. However, if you're getting more than just one object from Docs, it's still going to be 3.
Also, is there a reason why you're using BigIntegerField?
I'm trying to create a manager that has a method 'active_or_users' to retrieve all accounts that are active, or that an user has created. An active account has a start date that is either today, or somewhere in the past, and a end date that is somewhere in the future. Right now the active_or_users method works, however it returns duplicates of the same object. It's returning three copies of a user created active job. This is less than ideal.
from django.db.models import Q
from django.db import models
from django.contrib.auth.models import User
class ActiveJobs(models.Manager):
def active(self):
return super(ActiveJobs, self).get_query_set().\
filter(publications__publish_on__lte=date.today(),
publications__end_on__gt=date.today())
def active_or_users(self, user):
return super(ActiveJobs, self).get_query_set().\
filter((Q(publications__publish_on__lte=date.today()) &
Q(publications__end_on__gt=date.today())) | Q(creator=user))
class Job(models.Model):
title = models.CharField(max_length=100)
slug = models.SlugField(blank=True, null=True)
creator = models.ForeignKey(User)
objects = ActiveJobs()
class JobPublicationRecord(models.Model):
job = models.ForeignKey('Job', related_name='publications')
publish_on = models.DateField(auto_now=False)
end_on = models.DateField(auto_now=False, auto_now_add=False,
blank=True, null=True)
To put the comments into an answer
With the OR query, an instance will be returned for every hit of the query. I.e: an instance if a Job is created by user and another instance of the same job if also in the date range specified, etc.
So to fix this, change the method active_or_users to:
def active_or_users(self, user):
return super(ActiveJobs, self).get_query_set().filter(
(Q(publications__publish_on__lte=date.today()) &
Q(publications__end_on__gt=date.today())) | Q(creator=user)).distinct()
I have this model:
class LogBook_audit(models.Model):
id = models.AutoField(primary_key=True)
logbook = models.ForeignKey(LogBook, verbose_name='Logbook Control No.')
username = models.ForeignKey(User, null=True, blank=True, verbose_name='Username')
status = models.CharField(null=False, blank=False, max_length=40, choices=STATUS_TYPE, default=u'CHECKING REQUIREMENTS', verbose_name='Status')
log_in = models.DateTimeField(default=lambda:datetime.now(), verbose_name='Work start')
I'm trying to create a queryset to find latest user who log_in for such specific logbook and status.
view.py
undolink(request, pk):
undo_rec = LogBook.objects.get(pk=pk)
latest_user = LogBook_audit.objects.filter(logbook_id=pk, status=undo_rec.status).aggregate(Max('log_in'))
...
But latest_user is giving me a latest log_in format. I was thinking I can used latest_user.username but failed. Is there a way to find that username? Any guide is really appreciated.
You can use latest() instead:
latest_log = LogBook_audit.objects.filter(logbook_id=pk, status=undo_rec.status).latest('log_in')
then you can access user through latest_log.user.
You want to get a queryset result, so you should use annotate():
latest_user = (LogBook_audit.objects
.filter(logbook_id=pk, status=undo_rec.status)
.annotate(max_log_in=Max('log_in')))
Hope it helps.
I know that filtering by property is not possible with Django, as filtering is done at database level and properties live in Python code. However, I have the following scenario:
In one hand, I have the model RegisteredUser on the other hand Subscription. A user can have multiple subscriptions, a subscription is from one user and a user has one or none active subscriptions.
To implement this, I have a foreign key from Subscription to RegisteredUser and a property subscription at RegisteredUser that points to the active one (latest created subscription for that user) or none if he hasn't any subscriptions.
Which would be the most efficent way to filter users that have subscription "platinum", "gold", "silver"...? I could do a "fetch all subscriptions" and then iterate over them to check each one for a match. But it would be really expensive and if I have to do the same process for each kind of subscription type, then cost would be s * u (where s is the number of different subscriptions and u is the number of users).
Any help will be appreciated. Thanks in advance!
UPDATE:
When I first explained the problem, I didn't include all the models related to
simplify a litte. But as you are asking me for the models and some of you haven't understood me
(perhaps I wasn't clear enough) here you have the code.
I've simplified the models and stripped out code that is not important now.
What do I have here? A RegisteredUser can have many subscriptions (because he may change it
as many times as he wants), and a subscription is from just one user. The user has only
one current subscription, which is the latest one and is returned by the property
subscription. Subscription is attached with Membership and this is the model whose
slug can be: platinum, gold, silver, etc.
What do I need? I need to lookup Content whose author has a specific kind of membership.
If the property approach worked, I'd have done it like this:
Content.objects.filter(author__id__in=RegisteredUser.objects.filter(
subscription__membership__slug="gold"))
But I can't do this because properties can't be used when filtering!
I thought that I could solve the problem converting the "virtual" relation created by
the property into a real ForeignKey, but this may cause side effects, as I should update it manually each time a user changes its subscription and now it's automatic! Any better ideas?
Thanks so much!
class RegisteredUser(AbstractUser):
birthdate = models.DateField(_("Birthdate"), blank=True, null=True)
phone_number = models.CharField(_("Phone number"), max_length=9, blank=True, default="")
#property
def subscription(self):
try:
return self.subscriptions_set.filter(active=True).order_by("-date_joined",
"-created")[0]
except IndexError:
return None
class Subscription(models.Model):
date_joined = models.DateField(_("Date joined"), default=timezone.now)
date_canceled = models.DateField(_("Date canceled"), blank=True, null=True)
subscriber = models.ForeignKey(AUTH_USER_MODEL, verbose_name=_("Subscriber"),
related_name="subscriptions_set")
membership = models.ForeignKey(Membership, verbose_name=_("Membership"),
related_name="subscriptions_set")
created = models.DateTimeField(_("Created"), auto_now_add=True)
last_updated = models.DateTimeField(_("Last updated"), auto_now=True)
active = models.BooleanField(_("Active"), default=True)
class Membership(models.Model):
name = models.CharField(_("Name"), max_length=15)
slug = models.SlugField(_("Slug"), max_length=15, unique=True)
price = models.DecimalField(_("Price"), max_digits=6, decimal_places=2)
recurring = models.BooleanField(_("Recurring"))
duration = models.PositiveSmallIntegerField(_("Duration months"))
class Content(models.Model):
author = models.ForeignKey(AUTH_USER_MODEL, verbose_name=_("Author"),
related_name="contents_set")
title = models.CharField(_("Title"), max_length=50)
slug = models.SlugField(_("Slug"), max_length=70, unique=True)
content = RichTextField(_("Content"))
date = models.DateField(_("Date"), default=timezone.now)
published = models.BooleanField(_("Published"))
Finally, to solve the problem I replaced the subscription property by a real foreign key and added a signal to attach the RegisteredUser with the created subscription.
Foreign key:
subscription = models.ForeignKey(Subscription, verbose_name=_("Subscription"),
related_name='subscriber_set', blank=True, null=True)
Signal:
#receiver(post_save, sender=Subscription)
def signal_subscription_post_save(sender, instance, created, **kwargs):
if created:
instance.subscriber.subscription = instance
instance.subscriber.save()
I think you model are something like:
KIND = (("p", "platinum"), ("g","gold"), ("s","silver"),)
class RegisteredUser(models.Model):
# Fields....
class Subscription(models.Model):
kind = models.CharField(choices=KIND, max_len=2)
user = models.ForeignKey(RegisteredUser, related_name="subscriptions")
Now, you can do something like that:
gold_users = RegisteredUser.objects.filter(subscriptions_kind="g")
silver_users = RegisteredUser.objects.filter(subscriptions_kind="s")
platinum_users = RegisteredUser.objects.filter(subscriptions_kind="p")
Adapt it to your models
Hope helps
EDIT
Now, With your models, I think you want something like:
content_of_golden_users = Content.objects.filter(author__subscriptions_set__membership__slug="golden")
content_of_silver_users = Content.objects.filter(author__subscriptions_set__membership__slug="silver")
content_of_platinum_users = Content.objects.filter(author__subscriptions_set__membership__slug="platinum")