"以编程方式将图像保存到 Django ImageField"

Question

Ok, I've tried about near everything and I cannot get this to work.

Answer 1

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()

Answer 2

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.

Answer 3

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.

Answer 4

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

Answer 5

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.

Answer 6

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')

Answer 7

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)

Answer 8

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.

Answer 9

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)

Answer 10

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.

Answer 11

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()

Answer 12

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()

Answer 13

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()

Answer 14

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)

Answer 15

你可以试试：

model.ImageField.path = os.path.join('/Upload', generated_image_path)

Answer 16

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) 

Answer 17

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

Answer 18

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.

Answer 19

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()

Answer 20

if use admin.py you can solve by override ( doc on django<\/a> ):

def save_model(self, request, obj, form, change):
    obj.image_data = bytes(obj.image_name.read())
    super().save_model(request, obj, form, change)