Django admin Customize Field Upload files to the cloud Store links

brief introduction

At work, I met the need to quickly build a prototype ,Django There are perfect solutions for background data management .

admin Backstage right models.FileField The solution of uploading files is to store the original data directly in the database , It is inconvenient for database size and migration , More solutions are through oss Solve storage problems ,cdn Speed up access . So you need to models.FileField To transform , Make it automatically uploaded to oss And store url Address . After searching the network, there is only one solution to this , But incomplete. （ If there are other plans, please let us know in the comment area ）

Usage environment ：python 3.8.8 django 3.2.5

Implementation steps

notes ： I use Tencent cloud oss, So the following examples take Tencent cloud as an example , Other cloud oss Just replace the position marked by me

0、 Upload part of the file code （ Use of private information 000000 Express , Replace... By yourself ）

from qcloud_cos import CosConfig
from qcloud_cos import CosS3Client
from urllib.parse import quote

from config.config import TENCENTCloud_secret_id, TENCENTCloud_secret_key


class UploadToTencent(object):
    def __init__(self):
        self.region = 'ap-beijing'  #  Replace with the user's  Region
        self.scheme = 'https'  #  Specify the use of  http/https  Protocol to access  COS, The default is  https, Not required 
        self.config = CosConfig(Region=self.region,
                                SecretId=TENCENTCloud_secret_id,
                                SecretKey=TENCENTCloud_secret_key,
                                Scheme=self.scheme)

    def upload_to_tencentcloud(self, body='', key='', bucket='000000', default_dir=True):
        tencent_client = CosS3Client(self.config)
        if "000000" not in key and default_dir:
            key = "000000" + key
        if '/' in key:
            filename = key.split('/')[-1]
            file_dir = '/'.join(key.split('/')[:-1])+'/'
        else:
            filename = key
            file_dir = ''
        response = tencent_client.put_object(
            Bucket=bucket,
            Body=body,
            Key=key,
            EnableMD5=False
        )
        save_filename = quote(filename, 'utf-8')
        print(file_dir, save_filename)
        end_url = "https://download.000000.com/%s%s" % (file_dir, save_filename)
        return end_url

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1、 Customize Widget

Inherited forms.FileInput, Receive the page input file

# -*-*-*-*-*- encoding: utf-8 -*-*-*-*-
# @File : TencentWidget.py
# @Author : stonepy
# -*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-
from django import forms
from django.core.files.uploadedfile import InMemoryUploadedFile
from django.template import loader
from django.utils.safestring import mark_safe
from utils.tencentUploadFile import UploadToTencent


class TencentWidgets(forms.FileInput):
    template_name = 'tencent_input.html'   #

    def __init__(self, attrs=None, unique_list=None):
        """ :param attrs: :param unique_list:  Unique identification list , except id """
        super(TencentWidgets, self).__init__(attrs)
        self.unique = unique_list

    def format_value(self, value):
        return value

    def value_from_datadict(self, data, files, name):
        file = files.get(name)  # type:InMemoryUploadedFile
        if not file:
            return
        file_data = b''.join(chunk for chunk in file.chunks())  #  Take out the binary data 
        upload_cloud = UploadToTencent()
        url = upload_cloud.upload_to_tencentcloud(file_data, file.name)  #  How to replace this location when replacing other clouds , Method returns to url character string 
        return url

    def render(self, name, value, attrs=None, renderer=None):  #  Template rendering part 
        context = self.get_context(name, value, attrs)
        template = loader.get_template(self.template_name).render(context)
        return mark_safe(template)

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2、 Customize Field

Inherited models.URLField, Used to implement URL To deal with

from django import forms
from django.db import models

from customField.TencentWidget import TencentWidgets


class TencentField(models.URLField):
    def __init__(self, *args, **kwargs):
        self.app = kwargs.pop('app', '')
        self.table = kwargs.pop('table', '')
        self.unique_list = kwargs.pop('unique_list', '')
        super(TencentField, self).__init__(*args, **kwargs)

    def formfield(self, **kwargs):
        defaults = {
            'form_class': TencentFormField,
            'unique_list': self.unique_list
        }
        defaults.update(kwargs)
        return super(TencentField, self).formfield(**defaults)


class TencentFormField(forms.fields.URLField):
    def __init__(self, unique_list=None, **kwargs):
        kwargs.update({'widget': TencentWidgets(unique_list=unique_list)})
        super(TencentFormField, self).__init__(**kwargs)

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3、 Customize template

Here is the self exploration part , If you have any questions, please point out When not using custom templates , An error will be reported when entering, and the template cannot be found After browsing the source file, I found that /lib/python3.8/site-packages/django/forms/templates/django/forms/widgets/file.html, It is speculated that the corresponding position cannot be read file.html So customize a template html, The code is as follows ：（ Direct copy file.html Part of , Get rid of some unrecognized problems ）

<input type="{{ widget.type }}" name="{{ widget.name }}"{% if widget.value != None %} value="{{ widget.value }}"{% endif %}{% for name, value in widget.attrs.items %}{% if value is not False %} {{ name }}{% if value is not True %}="{{ value|stringformat:'s' }}"{% endif %}{% endif %}{% endfor %}>`
` Uploaded file ：{% if widget.value != None %}<a href="{{ widget.value }}">{{ widget.value }}</a>{% endif %}
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The last one is to add support for the display of uploaded files , I don't know what the previous problem is. It can't be displayed , If you don't need it, you can delete it directly

4、 Use customization field

from customField.TencentField import TencentField
file_url = TencentField(max_length=255, default='', verbose_name=' File address ', blank=True)

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5、 other

5.1 The code structure

5.2 Use effect

Page shows The database stores information

Refer to the article address ：www.jianshu.com/p/0522aaae3…