独立ucloud方法，添加ucloud配置类

ucloud/ucloud.py

@@ -0,0 +1,23 @@
+# https://github.com/ucloud/ufile-sdk-python
+import logging
+
+from ufile import filemanager
+
+from config.ucloud import PUBLIC_KEY, PRIVATE_KEY, UPLOAD_SUFFIX, DOWNLOAD_SUFFIX, BUCKET
+
+
+def get_private_url(key):
+    get_ufile_handler = filemanager.FileManager(PUBLIC_KEY, PRIVATE_KEY, UPLOAD_SUFFIX, DOWNLOAD_SUFFIX)
+
+    # 判断文件是否存在
+    _, resp = get_ufile_handler.head_file(BUCKET, key)
+    if resp.status_code != 200:
+        logging.warning("uCloud中未找到(%s)! status: %d error: %s", key, resp.status_code, resp.error)
+        return None
+
+    # 获取公有空间下载url
+    # url = get_ufile_handler.public_download_url(bucket, key)
+
+    # 获取私有空间下载url, expires为下载链接有效期，单位为秒
+    url = get_ufile_handler.private_download_url(BUCKET, key, expires=3600)
+    return url