I have these Models all of which have PointField:
class Place(models.Model):
title = models.CharField(max_length=75, verbose_name='Заголовок')
category = models.ForeignKey(PlaceCategory, verbose_name='Категория')
...
point = geomodels.PointField(geography=True, blank=True, null=True)
...
class Event(models.Model):
title = models.CharField(max_length=75, verbose_name='Заголовок')
address = models.CharField(max_length=255, blank=True, null=True, verbose_name='Адрес')
city = models.ForeignKey(City, verbose_name='Город')
...
point = geomodels.PointField(blank=True, null=True)
...
class Meeting(models.Model):
title = models.CharField(max_length=75)
participants = models.ManyToManyField(User, related_name='participating_meetings')
...
point = geomodels.PointField(blank=True, null=True)
...
In project I have /points API url. By this url I want to return filtered set or all the points to show them on map.
I checked DRF documentation, there is example how to build Serializer for one Model, but how do I build the API view for these multiple models?
This kind of use case is typical of where you'd need to drop the default auto generated things (serializer / view) and roll your own. I would gather the data by myself, run them through a PointSerializer - might be optional - which would inherit from Serializer and return the result.
Related
I am trying to adapt the Viewflow Dynamicsplit example
The objective is to split approvals of an Order based on OrderLines and to assign them to the appropriate approver. It seems that this should be possible as there seems to be a possibility described in this answer - Assign user to tasks automatically (Viewflow, Django)
The issue is that whenever I try to grab the current order pk in the DynamicSplitActivation - the queryset comes back empty. Not sure where I am going wrong. The queryset works fine if I set the pk manually, but as soon as I try to use a dynamic variable it stops working.
I have listed the flow and models etc. at the end of the post, however, I am guessing the issue is quite basic. Any help would be appreciated!
nodes.py
...
class DynamicSplitActivation(AbstractGateActivation):
def calculate_next(self):
self._order = self.flow_task._order_callback(self.process)
order_id = self._order.pk
# order_id = 28
order_lines = models.OrderLine.objects.filter(order_id=order_id)
project_lines = project_models.ProjectLine.objects.filter(orderline__in=order_lines)
users = User.objects.filter(projectline__in=project_lines).distinct()
self._approvers = users
...
class DynamicSplit(...):
...
def __init__(self, callback):
super(DynamicSplit, self).__init__()
self._order_callback = callback
self._ifnone_next_node = None
...
flows.py
...
approval_split = (
nodes.DynamicSplit(lambda act: act.order)
.IfNone(this.end)
.Next(this.split_approval_budget)
)
models.py
...
class ProjectLine(models.Model):
project = models.ForeignKey(Project, on_delete=models.CASCADE)
description = models.CharField(max_length=50)
budget_holder = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.SET_NULL, null=True, blank=True)
class Order(models.Model):
description = models.CharField(max_length=30)
class OrderLine(models.Model):
order = models.ForeignKey(Order, on_delete=models.CASCADE)
project_line = models.ForeignKey(project_models.ProjectLine, on_delete=models.SET_NULL, null=True, blank=False)
product = models.ForeignKey(catalogue_models.Product, on_delete=models.CASCADE)
quantity = models.PositiveIntegerField()
budgetholder_approved = models.BooleanField(null=True)
class OrderProccess(Process):
order = models.ForeignKey(Order, blank=True, null=True, on_delete=models.CASCADE)
...
I need to implement a "end-to-end" connection between products.
like this:
I automatically put down two-way links between two products. But when I link product A to product B and product B to product C, there is no connection between A and C. It is necessary that they communicate themselves when putting down the two previous links.
Models.py
from django.db import models
class Part(models.Model):
brand = models.CharField('Производитель', max_length=100, blank=True)
number = models.CharField('Артикул', max_length=100, unique=True)
name = models.CharField('Название', max_length=100, blank=True)
description = models.TextField('Комментарий', blank=True, max_length=5000)
analog = models.ManyToManyField('self',blank=True, related_name='AnalogParts')
images = models.FileField('Главное изображение', upload_to = 'parts/', blank=True)
images0 = models.FileField('Дополнительное фото', upload_to = 'parts/', blank=True)
images1 = models.FileField('Дополнительное фото', upload_to = 'parts/', blank=True)
images2 = models.FileField('Дополнительное фото', upload_to = 'parts/', blank=True)
def __str__(self):
return str(self.number)
return self.name
class Meta:
verbose_name = 'Запчасть'
verbose_name_plural = 'Запчасти'
Your diagram looks like Parts are connected linear. The easiest way to accomplish that is to add OneToOneFields to the model it self like so:
next = models.OneToOneField('self', related_name='previous', null=True)
Then you can do something like
part = Part.object.get(name='wheel')
while part.next:
part = part.next
# At this point Part is the last part in the row
print(part)
This is the most easy way. Depending whether you have linear connections between parts only you have to adjust your fields. There is no solution to all of the graph problems unless you realize some graph structure/database which will solve common problems (I think GraphQL can do such stuff, but iam not sure). Also keep in mind that this will most probably execute one SQL query per loop iteration.
I'm trying to figure it out on how I can show only a specific set of dynamic fields in eav to a unique registered model in my apps.models. But I don't know how to this, I've also read the documents but I can't seem to find anything about it, or maybe I've come across it and didn't understand.
Now, what is happening is that, when I add an attribute in the django admin. It also adds the dynamic field in all the models registered in the eav.
What I want to do is that;
model 1 - dynamic_field1, dynamic_field2, dynamic_field3
model 2 - dynamic_field4, dynamic_field5, dynamic_field6
Btw, I'm currently using the django-eav2 the documentation is in the link. I've found my solution for my initial use case here link
Below codes are basically on how to register my models to the eav. Here is my sample models
class ClientName(models.Model):
name = models.CharField(max_length=250, null=True, blank=True)
description = models.TextField(null=True, blank=True)
is_active = models.BooleanField(default=True)
def __str__(self):
return str(self.name)
class CallDetails(models.Model):
client_name = models.ForeignKey(ClientName, on_delete=models.PROTECT, null=True, blank=True, db_index=True)
letter_info = models.TextField(null=True, blank=True)
def __str__(self):
return str(self.client_name)
class Meta:
verbose_name = 'Call Detail'
ordering = ['client_name']
eav.register(ClientName)
eav.register(CallDetails)
below is my admin.py
class CallDetailsAdminForm(BaseDynamicEntityForm):
model = CallDetails
class CallDetailsAdmin(BaseEntityAdmin):
form = CallDetailsAdminForm
admin.site.register(CallDetails, CallDetailsAdmin)
Can someone tell me how to combine two or more attribute values of in another field by using instance?
Models.py:
fn_id = models.ForeignKey(FilemNumber, null=True, blank=True)
ln_id = models.ForeignKey(LineNumber, null=True, blank=True)
pn_id = models.ForeignKey(PhotoNumber, null=True, blank=True)
title = models.CharField(max_length=255,blank=True, null=True)
I want to combine fn_id, ln_id and pn_id and save the combination of the three values into field title.
You can do this:
from django import models
class BaseModel(models.Model):
fn_id = models.ForeignKey(FilemNumber, null=True, blank=True)
ln_id = models.ForeignKey(LineNumber, null=True, blank=True)
pn_id = models.ForeignKey(PhotoNumber, null=True, blank=True)
class YourModel(models.Model):
common = models.OneToOneField(BaseModel)
# I suppose that you want to get title, so let define title method
# if obj is an instance of YourModel, you can access title like this:
# obj.title
#property
def title(self):
return '{}{}{}{}'.format(self.id, self.common.fn_id,
self.common.ln_id, self.common.pn_id)
Lets read this article: https://docs.djangoproject.com/en/1.8/ref/models/fields/#onetoonefield
I have an Event model. Events can have many 'presenters'. But each presenter can either 1 of 2 different types of profiles. Profile1 and Profile2. How do I allow both profiles to go into presenters?
This will be 100% backend produced. As to say, admin will be selecting "presenters".
(Don't know if that matters or not).
class Profile1(models.Model):
user = models.ForeignKey(User, null=True, unique=True)
first_name = models.CharField(max_length=20, null=True, blank=True)
last_name = models.CharField(max_length=20, null=True, blank=True)
created = models.DateTimeField(auto_now_add=True)
modified = models.DateTimeField(auto_now=True)
about = models.TextField(null=True, blank=True)
tags = models.ManyToManyField(Tag, null=True, blank=True)
country = CountryField()
avatar = models.ImageField(upload_to='avatars/users/', null=True, blank=True)
score = models.FloatField(default=0.0, null=False, blank=True)
organization = models.CharField(max_length=2, choices=organizations)
class Profile2(models.Model):
user = models.ForeignKey(User, null=True, unique=True)
first_name = models.CharField(max_length=20, null=True, blank=True)
last_name = models.CharField(max_length=20, null=True, blank=True)
created = models.DateTimeField(auto_now_add=True)
modified = models.DateTimeField(auto_now=True)
about = models.TextField(null=True, blank=True)
tags = models.ManyToManyField(Tag, null=True, blank=True)
country = CountryField()
avatar = models.ImageField(upload_to='avatars/users/', null=True, blank=True)
score = models.FloatField(default=0.0, null=False, blank=True)
...
class Event(models.Model):
title = models.CharField(max_length=200)
sub_heading = models.CharField(max_length=200)
presenters = ManyToManyField(Profile1, Profile2, blank=True, null=True) ?
...
# I've also tried:
profile1_presenters = models.ManyToManyField(Profile1, null=True, blank=True)
profile2_presenters = models.ManyToManyField(Profile2, null=True, blank=True)
# is there a better way to accomplish this?...
I think you have a desing problem here. In my opinion, you must think what is a Presenter and what's the different between a Presenter with "profile 1" and with "profile 2". What are you going to do with this models? Are you sure there are just two profiles? Is there any chance that, in some time from now, a different profile ("profile 3") appears? And profile 4? and profile N?
I recommend you to think again about your models and their relations. Do NOT make this decision thinking of how difficul/easy will be to handle these models from django admin. That's another problem and i'll bet that if you think your models a little bit, this won't be an issue later.
Nevertheless, i can give you some advice of how to acomplish what you want (or i hope so). Once you have think abount how to model these relations, start thinking on how are you going to write your models in django. Here are some questions you will have to answer to yourself:
Do you need one different table (if you are going to use SQL) per profile?
If you cannot answer that, try to answer these:
1) What's the difference between two different profiles?
2) Are there more than one profile?
3) Each presenter have just one profile? What are the chances that this property changes in near future?
I don't know a lot about what you need but i think the best option is to have a model "Profile" apart of your "Presenter" model. May be something like:
class Profile(models.Model):
first_profile_field = ...
second_profile_field = ...
# Each presenter have one profile. One profile can "represent"
# to none or more presenters
class Presenter(models.Model):
first_presenter_field = ....
second_presenter_field = ....
profile = models.ForeignKey(Profile)
class Event(models.Model):
presenters = models.ManyToManyField(Presenter)
....
This is just an idea of how i imagine you could design your model. Here are some links that may help you once you have design your models correctly and have answered the questions i made to you:
https://docs.djangoproject.com/en/dev/topics/db/models/#model-inheritance
https://docs.djangoproject.com/en/dev/misc/design-philosophies/#models
http://www.martinfowler.com/eaaCatalog/activeRecord.html
And to work with the admin once you decide how your design will be:
https://docs.djangoproject.com/en/dev/ref/contrib/admin/
EDIT:
If i'm not wrong, the only difference between profile 1 and 2 fields is the "organization" field. Am i right? So i recommend you to merge both models since they are almost the same. If they have different methods, or you want to add different managers or whatever, you can use the proxy option of django models. For example, you can do this:
class Profile(models.Model):
#All the fields you listed above, including the "organization" field
class GoldenProfile(models.Model):
#you can define its own managers
objects = GoldenProfileManager()
....
class Meta:
proxy = True
class SilverProfile(models.Model):
....
class Meta:
proxy = True
This way, you can define different methods or the same method with a different behaviour in each model. You can give them their own managers, etcetera.
And the event class should stay like this:
class Event(models.Model):
title = models.CharField(max_length=200)
sub_heading = models.CharField(max_length=200)
presenters = ManyToManyField(Profile, blank=True, null=True)
Hope it helps!