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Update FileField value in instance Django Model save method

What is the best way the update the total field with value total the rows the file?
Implement in model or views or other? How to make The file registration will always be through django-admin
models.py
class Registry(models.Model):
file_upload = models.FileField(blank=True, null=False) #csv or xlsx
total = models.CharField(max_length=100, null=True, blank=True, default=None)
def save(self):
with open(self.file_upload) as f:
self.total = sum(1 for line in f)
return self.total
Error:
TypeError: expected str, bytes or os.PathLike object, not FieldFile

You can simply read the file content of the uploaded file as using .read() method.
And then do whatever you want to do with that content.
def save(self):
self.total = sum(1 for line in self.file_upload.read())
super(Registry, self).save(*args, **kwargs)
No need to again open at OS level.

The output of self.file_upload is a FieldFile object. You should change it to self.file_upload.path where will give you the string path of file.
And to makesure your self.file_upload is not None/Null, you should validate it also.
def save(self):
if self.file_upload:
with open(self.file_upload.path) as f:
....
You can read this docs for more https://docs.djangoproject.com/en/dev/topics/files/#using-files-in-models

I generally choose model part if I need to use the method for most of the instances that will be created. But in this case, I probably choose Django Forms to handle this business logic. By the way, you can choose all the possibilities. At least you can achieve what you need in both cases. If the business logics changes very often, I can suggest to move these logics to views or forms.
The error you have encountered is about open statement, which requires one of the types that declared in error message. To achieve that, you can change self.file_upload to self.file_upload.path which is the path that file uploaded. I strongly recommend you to use csv module or an excel file library to handle file read operations.

Uploading a file in django database in a specific root with diferrent folders everytime

I´m trying to upload file into database, but when i want put the function uoload to and i want to that function store the file in a root with the data the user submit in the for, for example year, course, section, I get that information and the file they uploaded I want to store in that subfolders, the code that I´m using only store the data in the Media_root, but not in the carpets how can I do in order to store the files in the subfolder I want. I'n my model document I store the information of the document, like the autor, the title,etc.
class File(models.Model):
titulo_file=models.ForeignKey(Document,on_delete=models.CASCADE,null=True,verbose_ name='Título de la Tesis')
file = models.FileField(null=True,blank=True, upload_to=generate_path)
Here the function I use to upload the file, Int only works to store the file into a folder with it´s same name.
def generate_path(instance, filename):
path =os.path.join(instance.file.name,filename)
return path
In my view, after the user submit the information, I use a os.path.join, that do the path with the information submited like this:
year/course/section
I want to send that path to my generate_path and store in that location the file, I tried with session but it doesn't work, what can I do?
models.py
class Year(models.Model):
year_number=models.CharField(max_length=10,primary_key=True)
class Course(models.Model):
name=models.CharField(max_length=50,primary_key=True)
class Section(models.Model):
numberSection=models.IntegerField(null=True,blank=True)
year = models.ForeignKey(Year, on_delete=models.CASCADE, null=True)
course = models.ForeignKey(Course, on_delete=models.CASCADE)
thopic_documents=(
('CS','CS'),
('SE','SE'),
('IS','IS'),
('IT','IT'),
)
class Document(models.Model):
title=models.CharField(max_length=200,primary_key=True)
thopic=models.CharField(max_length=50,choices=thopic_documents, default=None,null=True)
class Historial(models.Model):
id_section=models.ForeignKey(Section,on_delete=models.CASCADE)
title_document=models.ForeignKey(Document,on_delete=models.CASCADE,)

To get the year/course/section you need to be able to navigate from a File to a Section. However, the many-many relationship that exists between Document and Section through Historical makes it unclear how you would do that. Which Historical would you choose?
It may be better if File was linked directly to Historical:
class File(models.Model):
titulo_file=models.ForeignKey(Historical, on_delete=models.CASCADE,null=True,verbose_name='Título de la Tesis')
file = models.FileField(null=True,blank=True, upload_to=generate_path)
If that was the case, you could then implement your generate_path() such as:
def generate_path(instance, filename):
section = instance.titulo_file.id_section
year = section.year.year_number
course = section.course.name
return os.path.join(str(year), course, str(section.numberSection), filename)
To do the same thing with the model as it currently stands, you would have to do something like this:
def generate_path(instance, filename):
section = instance.titulo_file.historical_set.first().id_section
year = section.year.year_number
course = section.course.name
return os.path.join(str(year), course, str(section.numberSection), filename)
That example uses historical_set.first() to get the first Historical linked the Document. Maybe that would be ok, but otherwise you'd need to know which Historical to use.
Where a file with the same name is uploaded and you don't want to overwrite it, you could implement your own storage:
from django.core.files.storage import FileSystemStorage
class UseExistingStorage(FileSystemStorage):
def save(self, name, content, max_length=None):
if not self.exists(name):
return super().save(name, content, max_length)
return name # Don't save when the file exists, just return the name
Then reference the UseExistingStorage from your File model.
file = models.FileField(null=True,blank=True, upload_to=generate_path, storage=UseExistingStorage())

How to save a file to a model using upload_to for dynamic paths

I am trying to create a folder for each users to put their project in. So their file will have the path ..\project\id\filename, id is the user id and filename is the name of the file. Now using the arguments allowed for upload_to (instance and filename) in the Filefield, I realize that instance.id will be None and the path to the file will be ..\project\None\filename instead of ..\project\id\filename.
Now reading the Django documentation upload_to I saw this:
In most cases, this object will not have been saved to the database
yet, so if it uses the default AutoField, it might not yet have a
value for its primary key field.
My interpretation is that creating a new record and user_directory_path are not instantiated at the same time, that is, when I call create on Project model, instance.id will be None. My question is now, is there a way to get around this? While I see upload_to convenient, it is not necessarily convenient for dynamic path such as the one I am doing. I was thinking of creating the record, then adding the file path in an update, but I am in search of a way that can save everything in one step.
models.py
def user_directory_path(instance, filename):
# file will be uploaded to MEDIA_ROOT/user_<id>/<filename>
return 'project/{0}/{1}'.format(instance.user.id, filename)
class Project(models.Model):
email = models.ForeignKey(User,
to_field="email",
max_length=50
)
title = models.CharField(max_length=100)
date_created = models.DateTimeField(auto_now_add=True)
updated = models.DateTimeField(auto_now=True)
file = models.FileField(upload_to=user_directory_path, validators=[validate_file_type], null=True)
This is views.py when the form passes validation. Notice user_directory_path is called just before the create.
email = request.user.email
title = request.POST.get('title', '')
file = request.FILES['file']
filename = file.name
instance = Usermie.objects.get(email=request.user.email)
# Save to model
user_directory_path(instance=instance, filename=filename)
Project.objects.create(
title=title, file=file,
)

If, as you say, the id that you want to use in the file path is the id of the User, not the id of the Project.. then there's no problem because the User already exists when you are saving the Project. Since email is a foreign key to User, you would just do:
def user_directory_path(instance, filename):
# file will be uploaded to MEDIA_ROOT/user_<id>/<filename>
return 'project/{0}/{1}'.format(instance.email.id, filename)
But I will point out that, in the Django way of doing things, making a field called email that is a foreign key to User is actually pretty confusing. The field in the database will be called email_id.. and the value of the model field will return an instance of User.. not the actual email address, even though the email address is what's stored in the column. To get the email address you'd need to do one of:
myproject.email.email
myproject.email_id
Neither one is very clear. So unless you have a really good reason for doing it like that, you should call the field user and eliminate the to_field='email'. Allow Django to join the tables via id, which is the default behavior.
Then if you need the user email address you can get it any time via
myproject.user.email
And the bonus is that if the user changes their email address it will change everywhere, you don't have to rely on cascaded updates to fix all the foreign keys.
Trust me, when using Django you want to do ForeignKey by id (the default) unless there's a reason...

One simple solution can be saving object without file and then saving file like this
email = request.user.email
title = request.POST.get('title', '')
file = request.FILES['file']
filename = file.name
instance = Usermie.objects.get(email=request.user.email)
# Save to model
user_directory_path(instance=instance, filename=filename)
project = Project.objects.create(title=title)
project.file = file
project.save()

Django FileField upload_to assistance

I'm new to python and trying to adapt to the OOP of Python. Could someone explain why the following is saving in a folder called 'None'? I want to upload an audio file in the admin page. This file gets stored in its own folder with the 'Vocab name'
class Vocab(models.Model):
module = models.ForeignKey(Modules, on_delete=models.CASCADE)
number = models.CharField(max_length = 250)
name = models.CharField(max_length = 250)
class VocabContent(models.Model):
vocab = models.ForeignKey(Vocab, on_delete=models.CASCADE)
audio = models.FileField(upload_to=vocab.name)
Running the following on shell.
>>> from module.models import Modules, Vocab, VocabContent
>>> vocab = VocabContent.objects.get(pk=1)
>>> vocab.vocab.name
'Numbers'
Numbers is the value i am looking for.

It's probably because the way you reference vocab.name is not defined when your model migration is run. I can't explain precisely why this happens but a solution would be to use a callable as your upload_to to evaluate it at runtime and get the value correctly, much like this other answer: Dynamic File Path in Django
So, for you, you could have something like:
import os
def get_upload_path(instance, filename):
return os.path.join("%s" % instance.vocab.name, filename)
class VocabContent(models.Model):
vocab = models.ForeignKey(Vocab, on_delete=models.CASCADE)
audio = models.FileField(upload_to=get_upload_path) # Important to NOT put the parenthesis after the function name
Which would result in a path that concatenates the vocab.name to your file name for every new file.

CharField filenames into ImageFields in Django

I have a model:
class Photo(models.Model):
filename = models.CharField(max_length=240)
And a corresponding MySQL table, filled with filenames (copied from an existing table).
In the future I may want to upload new photos to the model via admin. Is it possible to evolve the current model into something with ImageFields and integrate my legacy data?

It is possible, assuming the current filename field in your model contains the full path to the actual file, you can add a new field (ImageField) to your model and migrate it using South, then write a script to update your data.
A skeleton example,
from django.core.files import File
# assuming your updated model looks like:
# class Photo(models.Model):
# filename = models.CharField(max_length=240)
# image = models.ImageField(max_length=240)
photos = Photo.objects.all()
for p in photos:
f = open(p.filename)
myimage = File(f)
p.image.save(image_name, myimage) # name, content
And then remove the old filename field via South. Take a look at Django's FileField first for more information, since ImageField essentially inherits all of the former's attribute and methods. (see https://docs.djangoproject.com/en/1.3/ref/models/fields/#django.db.models.FileField)