Last updated: 2020-01-16 16:20:10

COS uses XML APIs, which are lightweight, connectionless, and stateless. By calling XML APIs, you can send requests and accept responses directly through HTTP/HTTPS to interact with the COS backend.

Since COS APIs and TencentCloud APIs use different data transfer frameworks, APIs and SDKs provided by COS are independent of TencentCloud APIs and SDKs. You can find more information in API Operation List or download SDKs in SDK Overview. The guides for TencentCloud APIs and corresponding SDKs do not cover the operational features of COS.


Below are some main concepts and terms that may come up in the documentation:

Name Description
APPID A unique resource ID at the user level owned by a developer accessing COS services, which is used to identify resources
SecretId Developer-owned project ID for identity verification
SecretKey Developer-owned project key
Bucket A container used to store data in COS
Object A specific file stored in COS, which is the basic storage entity
Region Region in domain names such as ap-beijing, ap-hongkong, and eu-frankfurt. For enumerated values, see Regions and Access Domain Names
ACL Access Control List, a list of access control information for a specified bucket or object
CORS Cross-origin resource sharing (CORS).
This refers to HTTP requests where the origin of the resource that initiates the request is different from the origin of the destination resource
Multipart Uploads Multipart upload mode provided by Tencent Cloud COS service for uploading files in parts

Getting Started

Take the following steps to start using COS APIs:

  1. Activate the COS service in the COS Console.
  2. Create a bucket in the COS Console.
  3. Obtain the APPID, SecretId, and SecretKey on the Cloud API Key page in the CAM Console.
  4. Write a request signature algorithm program or use a server-side SDK. For more information, see Request Signature.
  5. Calculate the signature and call an API to perform an operation.