Python model get field

Python get a django model object by field

Solution 1: You can instead use method to get all the countries name and then send this data in json encoded form. Solution 2: If you want to try this without serializers means follow this, it is simple thing did in views.py itself..

Django model get field method

you can use the property method of the class. Which will access through the objects. You can just include that fields in the serializer.

class Lead(models.Model): price = models.IntegerField(_('price'), default=10) @property def total_price(self): ''' Looking for something like this ''' .. Logic . return self.price 

now you can include total_prcie field in serializer.

class LeadSerializer(serializers.ModelSerializer): class Meta: model = Lead fields = ('total_prize', ) 

I completed this task in a very different way, I had to create another table known as TrackLead Table to track when changes where made.

Later in __init__ function i updated the price field when required. I didnt find anyother way to complete it. However its working now .

Get Python type of Django’s model field?, I don’t think you can decide the actual python type programmatically there. Part of this is due to python’s dynamic type. If you look at the doc for converting values to python objects, there is no hard predefined type for a field: you can write a custom field that returns object in different types depending on the …

How to get the values in django model field?

You can instead use QuerySet.values_list() method to get all the countries name and then send this data in json encoded form.

def AllCountries(request): country_names = list(Countries.objects.values_list('country_name', flat=True)) data = return HttpResponse(json.dumps(data), content_type="application/json") 

You can use JsonResponse also instead of HttpResponse . There would be no need to do json.dumps() then as this will be performed by JsonResponse class itself.

def AllCountries(request): country_names = list(Countries.objects.values_list('country_name', flat=True)) data = return JsonResponse(data) 

If you want to try this without serializers means follow this, it is simple thing did in views.py itself..

data = map(lambda x:,Countries.objects.all()) return HttpResponse(content=json.dumps(),content_type="application/json") 

Simply Replace your 3 lines with above 2 lines and you may add field what ever you want from models inside dictionary.

Python — Django : Listing model field names and values, I’m trying to list fields and corresponding values of generic Django models in the templates. However I can’t find an inbuilt solution for a fairly common problem. I’m pretty close to the solution but can’t find a way out. view.py Code: def showdetails (request, template): objects = newivr1_model.objects.all () fields = …

How to get a field from a model in django api view

The problem is at this line:

py = Headline.objects.all().filter(title=title).order_by('-id') 

title is not a variable defined here.

If i understood you right you want to get just the field title, so you would get a response like:

To achieve this you could create another serializer for that view.

class HeadlineSerializer(serializers.ModelSerializer): class Meta: model = Headline fields = ['title', 'contentt'] class HeadlineTitleSerializer(serializers.ModelSerializer): class Meta: model = Headline #fields will filter you response for which fields you want to return in the response. fields = ['title'] 

@api_view(['GET',]) def api_detail(request, any): try: qs = Headline.objects.get(slug=any) except Headline.DoesNotExist: return Response(status = status.HTTP_404_NOT_FOUND) if request.method == "GET": serializer = HeadlineSerializer(qs) return Response(serializer.data) @api_view(['GET',]) def api_head(request): py = Headline.objects.all().order_by('-id') if request.method == "GET": serializer = HeadlineTitleSerializer(py, many=True) return Response(serializer.data) 

Python — django model get field method, I have a requirement, when a field say Price in a django model Lead is accessed I have to apply some business logic and update the price. I can accomplish in Serializers / Views. However this object is accessed by several views and hence its not a viable design to have a code in several place.

Django — getting objects by field value (model is unknown)

I don’t belive you can fetch an object from an SQL database, without searching each table it might be in.

However you can write a method in Django that does this for you:

def get_by_uuid(uuid): for Model in [Foo1, Foo2, Foo3]: try: return Model.objects.get(uuid=uuid) except Model.DoesNotExist: pass return None # Maybe you want to raise an exception here instead 

Note that the database will not ensure that uuids are unique across all tables, although if you use uuid.uuid4() to generate them, you shouldn’t get any collisions.

If you don’t want to hardcode the list of models, you could introspect your applications

Python — Django model field by variable, 1 Answer. Sorted by: 78. You can use pythons getattr function to do this. Pass the field name in as the attribute. getattr (model, fieldtoget) Since fieldtoget is a variable, this is dynamic. You can use setattr to set it the same way.

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How to get field data from model?

Another thing is that, after the user submit their query by choosing a value in the picklist, I will show them a table displaying the values of all the fields in the model. The doc of model fields specifies what Python type corresponds to each field type, so you can do this «statically».

How to get field data from model?

Say I have a Django application named app. Within it I have a model class defined in models.py named data. Also, I have a html file in the template directory that has several picklists, which should be populated with the fields of the model, such as type, date. What I need to do is to get the lists of the fields in the views.py and populate the picklists with them. Another thing is that, after the user submit their query by choosing a value in the picklist, I will show them a table displaying the values of all the fields in the model. So basically I have to retrieve what the user inputs, and query by the input, and get the data of all the fields in the model based on the query. We could name another two fields time, value. These things should be mostly done in views.py.

Here are the picklists in the hmtl file:

What I tried, for the two things, are:

1.To get the data to populate the picklist, I used:

objects= data.objects.all() type_data=getattr(objects, 'type') date_data=getattr(objects, 'date') 

2.To get the data after the query, I used:

if request.method == 'POST': … mytype = '% r' % request.POST.get['type'] mydate = ' %r ' % request.POST.get['date'] objects2= data.objects2.filter(type=mytype,date=mydate) time=getattr(objects2, 'time') value=getattr(objects2, 'value') 

It does not work. I am referencing this link django object get/set field so I’m basically using this to get field data from model: getattr(obj, ‘field_name’)

Any thoughts? I appreciate any help

Have a look at Django’s Form functionality – specifically ModelChoiceField – it solves this problem.

If you want to introspect a model to see what fields it has, have a look at model._meta.fields .

For example, the following code prints out the value for each field on a model instance instance :

for field in instance._meta.fields: print field.attname, '=', getattr(model, field.attname) 

your objects variable is a QuerySet, when materialized is a «list of objects», so to get list of object properties you should iterate over them:

objects = data.objects.all() type_data = [] date_date = [] for obj in objects: type_data.append(obj.type) date_date.append(obj.date) 

but i suppose what you will really need for the dropdown is to have an id for each value (but i may be wrong):

for obj in objects: type_data.append((obj.pk, obj.type)) date_date.append((obj.pk, obj.date)) 

this will create a list of tuples:

so in the template you can use:

but have in mind, that django can simplify this process — read about forms.

Python — How to get field data from model?, 2 Answers. Sorted by: 1. Have a look at Django’s Form functionality – specifically ModelChoiceField – it solves this problem. If you want to introspect a model to see what fields it has, have a look at model._meta.fields. For example, the following code prints out the value for each field on a model instance instance:

Get Python type of Django’s model field?

How can I get corresponding Python type of a Django model’s field class ?

from django.db import models class MyModel(models.Model): value = models.DecimalField() type(MyModel._meta.get_field('value')) #

I’m looking how can I get corresponding python type for field’s value — decimal.Decimal in this case.

p.s. I’ve attempted to work around this with field’s default attribute, but it probably won’t work in all cases where field has no default value defined.

I don’t think you can decide the actual python type programmatically there. Part of this is due to python’s dynamic type. If you look at the doc for converting values to python objects, there is no hard predefined type for a field: you can write a custom field that returns object in different types depending on the database value. The doc of model fields specifies what Python type corresponds to each field type, so you can do this «statically».

But why would you need to know the Python types in advance in order to serialize them? The serialize modules are supposed to do this for you, just throw them the objects you need to serialize. Python is a dynamically typed language.

An ugly alternative is to check the field’s repr():

if 'DecimalField' in repr(model._meta.get_field(fieldname)): return decimal.Decimal else: . 

However, you have to this for all types seperatly.

Python — How to get the value of a Django Model Field, Here is another solution to return the nth field of a model where all you know is the Model’s name. In the below solution the [1] field is the field after pk/id. model_obj = Model.objects.get (pk=pk) field_name = model_obj._meta.fields [1].name object_field_value = getattr (model_obj, field_name) Share.

Django. How to get fields from child model in views.py?

How to get fields from child model in views.py ? For example, I’ve parent model BasicOrder and child model (who extends BasicOrder ) TouristVisa .

I’m using Django 2.0.2 and Python 3.6.1. My models.py is:

class BasicOrder(models.Model): user = models.ForeignKey(User, verbose_name=_('User'), on_delete=models.CASCADE) status = models.PositiveIntegerField(_('Status'), choices=ORDER_STATUS, default=0) def __str__(self): return 'Order #<>'.format(self.id) class TouristVisa(BasicOrder, models.Model): citizenship = models.ForeignKey( Citizenship, verbose_name=_('Citizenship'), on_delete=models.PROTECT ) invitation_entry = models.PositiveSmallIntegerField( _('Invitation entry'), choices=INVITATION_ENTRY ) class Meta: ordering = ['id'] 

Would be great to have access to field invitation_entry from child model ( TouristVisa ). I try this way in views.py :

order = BasicOrder.objects.get(user=request.user.id) print(order.invitation_entry) 

AttributeError: ‘BasicOrder’ object has no attribute ‘invitation_entry’

It’s wrong, when TouristVisa inherits from BasicOrder it means it gets the fields user ans status as well, not the other way around. So, you can access the invitation_entry field but calling TouristVisa also because it’s the only model where it exists.

Now, access to it like this:

order = BasicOrder.objects.get(user=request.user.id) print(order.touristvisa.invitation_entry) 

Python — How to get data from django Model, 2 Answers. Django is «lazy» (see When is a Django QuerySet evaluated?) This can be bypassed by forcing a query to be executed e.g. by requesting the nbr of elements, in your example execute: class Training (models.Model): url = models.URLField (max_length=100) title = models.CharField (max_length=100) topic = …

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