how to change image format when uploading image in django? - python

When a user uploads an image from the Django admin panel, I want to change the image format to '.webp'. I have overridden the save method of the model. Webp file is generated in the media/banner folder but the generated file is not saved in the database. How can I achieve that?
def save(self, *args, **kwargs):
super(Banner, self).save(*args, **kwargs)
im = Image.open(self.image.path).convert('RGB')
name = 'Some File Name with .webp extention'
im.save(name, 'webp')
self.image = im
But After saving the model, instance of the Image class not saved in the database?
My Model Class is :
class Banner(models.Model):
image = models.ImageField(upload_to='banner')
device_size = models.CharField(max_length=20, choices=Banner_Device_Choice)

from django.core.files import ContentFile
If you already have the webp file, read the webp file, put it into the ContentFile() with a buffer (something like io.BytesIO). Then you can proceed to save the ContentFile() object to a model. Do not forget to update the model field, and save the model!
https://docs.djangoproject.com/en/4.1/ref/files/file/
Alternatively
"django-webp-converter is a Django app which straightforwardly converts static images to WebP images, falling back to the original static image for unsupported browsers."
It might have some save capabilities too.
https://django-webp-converter.readthedocs.io/en/latest/
The cause
You are also saving in the wrong order, the correct order to call the super().save() is at the end.
Edited, and tested solution:
from django.core.files import ContentFile
from io import BytesIO
def save(self, *args, **kwargs):
#if not self.pk: #Assuming you don't want to do this literally every time an object is saved.
img_io = BytesIO()
im = Image.open(self.image).convert('RGB')
im.save(img_io, format='WEBP')
name="this_is_my_webp_file.webp"
self.image = ContentFile(img_io.getvalue(), name)
super(Banner, self).save(*args, **kwargs) #Not at start anymore

hello do it like this:
...
from django.db.models.signals import post_save
from django.dispatch import receiver
class Banner(models.Model):
image = models.ImageField(upload_to='banner')
device_size = models.CharField(max_length=20,choices=Banner_Device_Choice)
#receiver(post_save, sender=Banner)
def create_webp(sender, instance, created, **kwargs):
path = instance.image.path
if instance.image.path[-4:] !=webp:
im = Image.open(path).convert('RGB')
extention = instance.image.path.rsplit(".",2)[1]
file_name = path.replace(extention,"webp")
im.save(file_name, 'webp')
instance.image.path = file_name
instance.save()

Related

Overwriting Image with same name - Django

Through my project, I have users upload a profile picture. I save the profile picture as userID.jpg. If they upload a new profile picture, I want to overwrite the old profile picture, so I don't waste storage space. By browsing previously asked questions on stackoverflow, I redefined the OverwriteStorage:
class OverwriteStorage(FileSystemStorage):
def get_available_name(self, name, max_length=None):
if self.exists(name):
os.remove(os.path.join(settings.MEDIA_ROOT, name))
return name
When I upload the profile picture, I can see in the directory on my computer that the picture has been overwritten successfully.The image is saved with the path "media/profile/userID.jpg". However, when I display the image on my site, it is still the old picture.
Through the Django site, when I open the path, I see the old picture, and when I try to change it through the admin, I get the following error:
[WinError 32] The process cannot access the file because it is being used by another process: '\media\\profile\\userID.jpg'
I guess I am incorrectly overwriting the file and another instance is still open, and to solve it, I need to properly close the image before overwriting. I tried doing that, but to to no success.
I did something similar but I used signals to update and delete images.
Firstable, I defined the name of the image in the helpers.py
from django.conf import settings
from datetime import datetime
def upload_to_image_post(self, filename):
"""
Stores the image in a specific path regards to date
and changes the name of the image with for the name of the post
"""
ext = filename.split('.')[-1]
current_date = datetime.now()
return '%s/posts/main/{year}/{month}/{day}/%s'.format(
year=current_date.strftime('%Y'), month=current_date.strftime('%m'),
day=current_date.strftime('%d')) % (settings.MEDIA_ROOT, filename)
SO, I called the def in my model, specifically in the image's field
from django.db import models
from django.utils.text import slugify
from .helpers import upload_to_image_post
class Post(models.Model):
"""
Store a simple Post entry.
"""
title = models.CharField('Title', max_length=200, help_text='Title of the post')
body = models.TextField('Body', help_text='Enter the description of the post')
slug = models.SlugField('Slug', max_length=200, db_index=True, unique=True, help_text='Title in format of URL')
image_post = models.ImageField('Image', max_length=80, blank=True, upload_to=upload_to_image_post, help_text='Main image of the post')
class Meta:
verbose_name = 'Post'
verbose_name_plural = 'Posts'
Finally, I defined signals to update or delete the image before the actions (update or delete) happen in the model.
import os
from django.db import models
from django.dispatch import receiver
from django.db.models.signals import pre_delete, pre_save
from .models import Post
#receiver(pre_delete, sender=Post)
def post_delete(sender, instance, **kwargs):
"""
Deleting the specific image of a Post after delete it
"""
if instance.image_post:
if os.path.isfile(instance.image_post.path):
os.remove(instance.image_post.path)
#receiver(pre_save, sender=Post)
def post_update(sender, instance, **kwargs):
"""
Replacing the specific image of a Post after update
"""
if not instance.pk:
return False
if sender.objects.get(pk=instance.pk).image_post:
old_image = sender.objects.get(pk=instance.pk).image_post
new_image = instance.image_post
if not old_image == new_image:
if os.path.isfile(old_image.path):
os.remove(old_image.path)
else:
return False
I hope, this helped you.
It is interesting to receive and process via signals. In some cases, it may be more convenient than OverwriteStorage(FileSystemStorage).
But, os.remove(filename) is not safe/working without local filesystem. I recommend using Django File Storage API.
from django.core.files.storage import default_storage
os.path.isfile(path) # worse
default_storage.exists(path) # better
os.remove(path) # worse
default_storage.delete(path) # better
Have it rename the old one to userID-old.jpg and then save userID.jpg. It will be quick that no one would likely notice it happening.

sorl-thumbnail giving incorrect url on refresh

I am trying to resize images before uploading them and then sending back url as json value.
This is how my model looks like:
class Picture(models.Model):
picid = models.AutoField(null=False, unique=True, primary_key=True)
user = models.ForeignKey(User, on_delete=models.CASCADE)
large = ImageField(upload_to=Helper.createPhotoName)
med = ImageField(upload_to=Helper.createPhotoName)
small = ImageField(upload_to=Helper.createPhotoName)
def save(Self, *args, **kwargs):
super(Picture, self).save(*args, **kwargs)
self.med = get_thumbnail(self.large, '150x150', crop='center', quality=99)
self.small = get_thumbnail(self.large, '80x80', crop='center', quality=99)
After the user uploads the image, it saves it into the model, gets the url and sends it back to the client.
self.f = request.Files['file']
usr = User.objects.get(pk=self.uid)
pic = usr.picture_set.create(large=self.f, med=self.f, small=self.f)
self.data['med'] = pic.med.url
self.data['small'] = pic.small.url
Afterwards, in another view, saved image is always looked for in database whenever the page is reloaded or revisited to show the older image and an option to change it.
pic = Picture.objects.get(user=uid)
self.data['photo'] = {
'small': pic.small.url,
'med': pic.med.url,
'silh': False
}
While first time I get the right url but second time I am getting a wrong one. I get 3 images for each upload in my upload_to path and 3 resized images in a cache directory at MEDIA_ROOT. In picture table upload_to path is being saved not the cache one, while the resized images lie in cache directory.
In thumbnail_kvstore table, I can see the path of resized image as name dict key. Just after uploading I get an url of the cache, but on refresh I get url of the upload_to path and I am not able to get resized image. What could be the problem?
You should call the save() after the setting of the thumnbail fields:
def save(Self, *args, **kwargs):
self.med = get_thumbnail(self.large, '150x150', crop='center',
quality=99).name
self.small = get_thumbnail(self.large, '80x80', crop='center',
quality=99).name
super(Picture, self).save(*args, **kwargs)

django submit image fom url file name stored wrong

I'm trying to submit image from url based on the answers of this question but as a result I have image file stored successfully , but with filename .jpg instead of image-name.jpg
code
import urllib2
from django.core.files import File
from django.core.files.temp import NamedTemporaryFile
from myapp.models import Mymodel
# Mymodel contain ImageField named image
extract_url = 'http://example.com/image-name.jpg'
my_temp = Mymodel()
image_name = extract_url.split('/')[-1]
image_temp = NamedTemporaryFile(delete=True)
image_temp.write(urllib2.urlopen(extract_url).read())
image_temp.flush()
my_temp.image.save(image_name, File(image_temp), save=True)
I did not overwrite Mymodel save method and image_name value is image-name.jpg
>> print image_name
u'image-name.jpg'
EDIT : Include Mymodel code
def _image_container(instance, filename):
return os.path.join(settings.IMAGE_FILES_ROOT, instance.slug + '.' + filename.split('.')[-1].lower())
class Mymodel(models.Model):
...
slug = AutoSlugField(_('Slug'), unique=True, populate_from='title', editable=True)
image = thumbnail.ImageField(_('Image'), upload_to=_image_container)
I want to keep _image_container functionality because it works nice on manual upload
Your upload_to _image_container function renames the image based on the Mymodel instance's slug, but the model instance you use for saving your image has no slug, so obviously you have exactly what you asked for... To make a long story short you have to explicitely set the slug attribute of your temporary Mymodel instance to whatever name you want for the image.
import os
extract_url = 'http://example.com/image-name.jpg'
image_name = extract_url.split('/')[-1]
slug = os.path.splitext(image_name)[0]
my_temp = Mymodel(slug=slug)
# etc

Remove previous image from media folder when ImageFiled entry modified in Django

I have a Model with a ImageField.
class Photo(models.Model):
----
image = models.ImageField(verbose_name=_('Image'),upload_to='images/category/%Y/%m/%d/',
max_length=200,null=True,blank=True)
---
I edited this model and changed the image field by uploading a new image.
My question, Is there a way to delete the previous image from its directory(from media folder) when I updates this entry with new image. I am using django 1.4.3 .
You can either use django's signals or simply overwrite the save method on your model. I would write a signal. Something like the following (note that this is untested):
from django.db.models.signals import pre_save
from django.dispatch import receiver
class Photo(models.Model):
image = ...
#receiver(pre_save, sender=Photo)
def delete_old_image(sender, instance, *args, **kwargs):
if instance.pk:
existing_image = Photo.objects.get(pk=instance.pk)
if instance.image and existing_image.image != instance.image:
existing_image.image.delete(False)

Programmatically saving image to Django ImageField

Ok, I've tried about near everything and I cannot get this to work.
I have a Django model with an ImageField on it
I have code that downloads an image via HTTP (tested and works)
The image is saved directly into the 'upload_to' folder (the upload_to being the one that is set on the ImageField)
All I need to do is associate the already existing image file path with the ImageField
I've written this code about 6 different ways.
The problem I'm running into is all of the code that I'm writing results in the following behavior:
(1) Django will make a 2nd file, (2) rename the new file, adding an _ to the end of the file name, then (3) not transfer any of the data over leaving it basically an empty re-named file. What's left in the 'upload_to' path is 2 files, one that is the actual image, and one that is the name of the image,but is empty, and of course the ImageField path is set to the empty file that Django try to create.
In case that was unclear, I'll try to illustrate:
## Image generation code runs....
/Upload
generated_image.jpg 4kb
## Attempt to set the ImageField path...
/Upload
generated_image.jpg 4kb
generated_image_.jpg 0kb
ImageField.Path = /Upload/generated_image_.jpg
How can I do this without having Django try to re-store the file? What I'd really like is something to this effect...
model.ImageField.path = generated_image_path
...but of course that doesn't work.
And yes I've gone through the other questions here like this one as well as the django doc on File
UPDATE
After further testing, it only does this behavior when running under Apache on Windows Server. While running under the 'runserver' on XP it does not execute this behavior.
I am stumped.
Here is the code which runs successfully on XP...
f = open(thumb_path, 'r')
model.thumbnail = File(f)
model.save()
I have some code that fetches an image off the web and stores it in a model. The important bits are:
from django.core.files import File # you need this somewhere
import urllib
# The following actually resides in a method of my model
result = urllib.urlretrieve(image_url) # image_url is a URL to an image
# self.photo is the ImageField
self.photo.save(
os.path.basename(self.url),
File(open(result[0], 'rb'))
)
self.save()
That's a bit confusing because it's pulled out of my model and a bit out of context, but the important parts are:
The image pulled from the web is not stored in the upload_to folder, it is instead stored as a tempfile by urllib.urlretrieve() and later discarded.
The ImageField.save() method takes a filename (the os.path.basename bit) and a django.core.files.File object.
Let me know if you have questions or need clarification.
Edit: for the sake of clarity, here is the model (minus any required import statements):
class CachedImage(models.Model):
url = models.CharField(max_length=255, unique=True)
photo = models.ImageField(upload_to=photo_path, blank=True)
def cache(self):
"""Store image locally if we have a URL"""
if self.url and not self.photo:
result = urllib.urlretrieve(self.url)
self.photo.save(
os.path.basename(self.url),
File(open(result[0], 'rb'))
)
self.save()
Super easy if model hasn't been created yet:
First, copy your image file to the upload path (assumed = 'path/' in following snippet).
Second, use something like:
class Layout(models.Model):
image = models.ImageField('img', upload_to='path/')
layout = Layout()
layout.image = "path/image.png"
layout.save()
tested and working in django 1.4, it might work also for an existing model.
Just a little remark. tvon answer works but, if you're working on windows, you probably want to open() the file with 'rb'. Like this:
class CachedImage(models.Model):
url = models.CharField(max_length=255, unique=True)
photo = models.ImageField(upload_to=photo_path, blank=True)
def cache(self):
"""Store image locally if we have a URL"""
if self.url and not self.photo:
result = urllib.urlretrieve(self.url)
self.photo.save(
os.path.basename(self.url),
File(open(result[0], 'rb'))
)
self.save()
or you'll get your file truncated at the first 0x1A byte.
Ok, If all you need to do is associate the already existing image file path with the ImageField, then this solution may be helpfull:
from django.core.files.base import ContentFile
with open('/path/to/already/existing/file') as f:
data = f.read()
# obj.image is the ImageField
obj.image.save('imgfilename.jpg', ContentFile(data))
Well, if be earnest, the already existing image file will not be associated with the ImageField, but the copy of this file will be created in upload_to dir as 'imgfilename.jpg' and will be associated with the ImageField.
Here is a method that works well and allows you to convert the file to a certain format as well (to avoid "cannot write mode P as JPEG" error):
import urllib2
from django.core.files.base import ContentFile
from PIL import Image
from StringIO import StringIO
def download_image(name, image, url):
input_file = StringIO(urllib2.urlopen(url).read())
output_file = StringIO()
img = Image.open(input_file)
if img.mode != "RGB":
img = img.convert("RGB")
img.save(output_file, "JPEG")
image.save(name+".jpg", ContentFile(output_file.getvalue()), save=False)
where image is the django ImageField or your_model_instance.image
here is a usage example:
p = ProfilePhoto(user=user)
download_image(str(user.id), p.image, image_url)
p.save()
Hope this helps
What I did was to create my own storage that will just not save the file to the disk:
from django.core.files.storage import FileSystemStorage
class CustomStorage(FileSystemStorage):
def _open(self, name, mode='rb'):
return File(open(self.path(name), mode))
def _save(self, name, content):
# here, you should implement how the file is to be saved
# like on other machines or something, and return the name of the file.
# In our case, we just return the name, and disable any kind of save
return name
def get_available_name(self, name):
return name
Then, in my models, for my ImageField, I've used the new custom storage:
from custom_storage import CustomStorage
custom_store = CustomStorage()
class Image(models.Model):
thumb = models.ImageField(storage=custom_store, upload_to='/some/path')
A lot of these answers were outdated, and I spent many hours in frustration (I'm fairly new to Django & web dev in general). However, I found this excellent gist by #iambibhas: https://gist.github.com/iambibhas/5051911
import requests
from django.core.files import File
from django.core.files.temp import NamedTemporaryFile
def save_image_from_url(model, url):
r = requests.get(url)
img_temp = NamedTemporaryFile(delete=True)
img_temp.write(r.content)
img_temp.flush()
model.image.save("image.jpg", File(img_temp), save=True)
Another possible way to do that:
from django.core.files import File
with open('path_to_file', 'r') as f: # use 'rb' mode for python3
data = File(f)
model.image.save('filename', data, True)
If you want to just "set" the actual filename, without incurring the overhead of loading and re-saving the file (!!), or resorting to using a charfield (!!!), you might want to try something like this --
model_instance.myfile = model_instance.myfile.field.attr_class(model_instance, model_instance.myfile.field, 'my-filename.jpg')
This will light up your model_instance.myfile.url and all the rest of them just as if you'd actually uploaded the file.
Like #t-stone says, what we really want, is to be able to set instance.myfile.path = 'my-filename.jpg', but Django doesn't currently support that.
This is might not be the answer you are looking for. but you can use charfield to store the path of the file instead of ImageFile. In that way you can programmatically associate uploaded image to field without recreating the file.
With Django 3,
with a model such as this one:
class Item(models.Model):
name = models.CharField(max_length=255, unique=True)
photo= models.ImageField(upload_to='image_folder/', blank=True)
if the image has already been uploaded, we can directly do :
Item.objects.filter(...).update(photo='image_folder/sample_photo.png')
or
my_item = Item.objects.get(id=5)
my_item.photo='image_folder/sample_photo.png'
my_item.save()
You can try:
model.ImageField.path = os.path.join('/Upload', generated_image_path)
class tweet_photos(models.Model):
upload_path='absolute path'
image=models.ImageField(upload_to=upload_path)
image_url = models.URLField(null=True, blank=True)
def save(self, *args, **kwargs):
if self.image_url:
import urllib, os
from urlparse import urlparse
file_save_dir = self.upload_path
filename = urlparse(self.image_url).path.split('/')[-1]
urllib.urlretrieve(self.image_url, os.path.join(file_save_dir, filename))
self.image = os.path.join(file_save_dir, filename)
self.image_url = ''
super(tweet_photos, self).save()
class Pin(models.Model):
"""Pin Class"""
image_link = models.CharField(max_length=255, null=True, blank=True)
image = models.ImageField(upload_to='images/', blank=True)
title = models.CharField(max_length=255, null=True, blank=True)
source_name = models.CharField(max_length=255, null=True, blank=True)
source_link = models.CharField(max_length=255, null=True, blank=True)
description = models.TextField(null=True, blank=True)
tags = models.ForeignKey(Tag, blank=True, null=True)
def __unicode__(self):
"""Unicode class."""
return unicode(self.image_link)
def save(self, *args, **kwargs):
"""Store image locally if we have a URL"""
if self.image_link and not self.image:
result = urllib.urlretrieve(self.image_link)
self.image.save(os.path.basename(self.image_link), File(open(result[0], 'r')))
self.save()
super(Pin, self).save()
Working!
You can save image by using FileSystemStorage.
check the example below
def upload_pic(request):
if request.method == 'POST' and request.FILES['photo']:
photo = request.FILES['photo']
name = request.FILES['photo'].name
fs = FileSystemStorage()
##### you can update file saving location too by adding line below #####
fs.base_location = fs.base_location+'/company_coverphotos'
##################
filename = fs.save(name, photo)
uploaded_file_url = fs.url(filename)+'/company_coverphotos'
Profile.objects.filter(user=request.user).update(photo=photo)
class DemoImage(models.Model):
title = models.TextField(max_length=255, blank=False)
image = models.ImageField(blank=False, upload_to="images/DemoImages/")
import requests
import urllib.request
from django.core.files import File
url = "https://path/to/logo.jpg"
# Below 3 lines is to fake as browser agent
# as many sites block urllib class suspecting to be bots
opener = urllib.request.build_opener()
opener.addheaders = [("User-agent", "Mozilla/5.0")]
urllib.request.install_opener(opener)
# Issue command to actually download and create temp img file in memory
result = urllib.request.urlretrieve(url)
# DemoImage.objects.create(title="title", image=File(open(result[0], "rb")))
# ^^ This erroneously results in creating the file like
# images/DemoImages/path/to/temp/dir/logo_image_file
# as opposed to
# images/DemoImages/logo_image_file
# Solution to get the file in images/DemoImages/
reopen = open(result[0], "rb") # Returns a BufferedReader object of the temp image
django_file = File(reopen) # Create the file from the BufferedReader object
demoimg = DemoImage()
demoimg.title = "title"
demoimg.image.save("logo.png", django_file, save=True)
This approach also triggers file upload to cloudinary/S3 if so configured
So, if you have a model with an imagefield with an upload_to attribute set, such as:
class Avatar(models.Model):
image_file = models.ImageField(upload_to=user_directory_path_avatar)
then it is reasonably easy to change the image, at least in django 3.15.
In the view, when you process the image, you can obtain the image from:
self.request.FILES['avatar']
which is an instance of type InMemoryUploadedFile, as long as your html form has the enctype set and a field for avatar...
<form method="post" class="avatarform" id="avatarform" action="{% url avatar_update_view' %}" enctype="multipart/form-data">
{% csrf_token %}
<input id="avatarUpload" class="d-none" type="file" name="avatar">
</form>
Then, setting the new image in the view is as easy as the following (where profile is the profile model for the self.request.user)
profile.avatar.image_file.save(self.request.FILES['avatar'].name, self.request.FILES['avatar'])
There is no need to save the profile.avatar, the image_field already saves, and into the correct location because of the 'upload_to' callback function.
Your can use Django REST framework and python Requests library to Programmatically saving image to Django ImageField
Here is a Example:
import requests
def upload_image():
# PATH TO DJANGO REST API
url = "http://127.0.0.1:8080/api/gallery/"
# MODEL FIELDS DATA
data = {'first_name': "Rajiv", 'last_name': "Sharma"}
# UPLOAD FILES THROUGH REST API
photo = open('/path/to/photo', 'rb')
resume = open('/path/to/resume', 'rb')
files = {'photo': photo, 'resume': resume}
request = requests.post(url, data=data, files=files)
print(request.status_code, request.reason)
I save the image with uuid in django 2 python 3 because thats how django do it:
import uuid
from django.core.files import File
import urllib
httpUrl = "https://miimgeurl/image.jpg"
result = urllib.request.urlretrieve(httpUrl)
mymodel.imagefield.save(os.path.basename(str(uuid.uuid4())+".jpg"),File(open(result[0], 'rb')))
mymodel.save()
if you use admin.py you can solve the problem override (doc on django):
def save_model(self, request, obj, form, change):
obj.image_data = bytes(obj.image_name.read())
super().save_model(request, obj, form, change)
with models.py:
image_name = models.ImageField()
image_data = models.BinaryField()

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