Django project practice (mall): 14. Supplement: Django file storage class url()

(According to the content of teacher's live broadcast)

1. Introduction to Django file storage class url() method

• in conclusion:
  • The function of the file storage class url() method: returns the URL of the file content represented by name.
  • File storage class url() method trigger: content.image.url
    • Although the url method of ImageField is called on the surface. But internally it will call the url() method of the file storage class.
  • Use of file storage class url() method:
    • We can achieve the purpose of rewriting the url() method by customizing the Django file storage class.
    • The custom Django file storage class must provide the url() method.
    • Returns the absolute URL corresponding to the file pointed to by name.

Two, custom Django file storage class

• Official documentation of custom file storage class: https://docs.djangoproject.com/en/2.2/howto/custom-file-storage/

1. Rewrite the url() method of Django file storage class

class FastDFSStorage(Storage):
    """自定义文件存储系统，修改存储的方案"""
    def __init__(self, fdfs_base_url=None):
        """
        构造方法，可以不带参数，也可以携带参数
        :param base_url: Storage的IP
        """
        # if not fdfs_base_url:
        #     self.fdfs_base_url = settings.FDFS_BASE_URL
        # else:
        # 	  self.fdfs_base_url = fdfs_base_url
        self.fdfs_base_url = fdfs_base_url or settings.FDFS_BASE_URL
    def _open(self, name, mode='rb'):
        ......
    def _save(self, name, content):
        ......
    def url(self, name):
        """
        返回name所指文件的绝对URL
        :param name: 要读取文件的引用:group1/M00/00/00/wKhnnlxw_gmAcoWmAAEXU5wmjPs35.jpeg
        :return: http://192.168.103.158:8888/group1/M00/00/00/wKhnnlxw_gmAcoWmAAEXU5wmjPs35.jpeg
        """
        # return 'http://192.168.15.134.158:8888/' + name
        # return 'http://image.meiduo.site:8888/' + name
        return self.fdfs_base_url + name

2. Related configuration parameters

# 指定自定义的Django文件存储类
DEFAULT_FILE_STORAGE = 'lgshop.utils.fastdfs.fdfs_storage.FastDFSStorage'
# FastDFS相关参数
# FDFS_BASE_URL = 'http://192.168.15.134:8888/'
FDFS_BASE_URL = 'http://image.meiduo.site:8888/'

3. Add the domain name to access the picture

• Add the domain name to access Storage in /etc/hosts

#Storage的IP        域名
192.168.15.134    image.meiduo.site

4. Use of file storage class url() method

• Take the picture carousel as an example: content.image.url

<ul class="slide">
    {% for content in contents.index_lbt %}
    <li><a href="{
     
     { content.url }}"><img src="{
     
     { content.image.url }}" alt="{
     
     { content.title }}"></a></li>
    {% endfor %}
</ul>

5. Turn on the virtual machine: open the storage tracker page to display all the pictures

• Open fastdfs service
  
• Visit homepage