Refreshes files on Alibaba Cloud CDN points of presence (POPs). After files are refreshed, the original file content immediately becomes invalid. If clients request the original file content, Alibaba Cloud CDN forwards the requests to the origin server. Then, Alibaba Cloud CDN caches the latest content to the POPs and returns the content to the clients. Alibaba Cloud CDN allows you to refresh content from multiple URLs at the same time.
Operation description
- Alibaba Cloud CDN supports POST requests in which parameters are sent as a form.
- You can call the RefreshObjectCaches operation to refresh content and call the PushObjectCache operation to prefetch content.
- You can call the RefreshObjectCaches operation up to 50 times per second per account.
- For more information about how to automatically refresh or prefetch tasks, see Run scripts to refresh and prefetch content.
Precautions
- After a refresh task is submitted and completed, specific resources are removed from POPs. When a POP receives a request for the removed resources, the POP forwards the request to the origin server to retrieve the resources. The retrieved resources are returned to the client and cached on the POP. Multiple refresh tasks may cause a large number of resources to be removed from the POPs. This increases the number of requests that are forwarded to the origin server. The back-to-origin routing process consumes more bandwidth resources and the origin server may be overwhelmed.
- A refresh task takes effect 5 to 6 minutes after being submitted. This means that if the resource you want to refresh has a TTL of less than five minutes, you wait for it to expire instead of manually running a refresh task.
- If you want to use RAM users to refresh or prefetch resources, you must obtain the required permissions. For more information, see Authorize a RAM user to prefetch and refresh resources.
Refresh quota
- By default, each Alibaba Cloud account can refresh content from up to 10,000 URLs and 100 directories per day. The directories include subdirectories. If the daily peak bandwidth value exceeds 200 Mbit/s, you can submit a ticket to request a quota increase. Alibaba Cloud CDN evaluates your application based on your workloads.
- By default, each Alibaba Cloud account can submit up to 20 refresh rules that contain regular expressions per day. If the daily peak bandwidth of your Alibaba Cloud account exceeds 10 Gbit/s, you can submit a ticket to request a quota increase.
- You can specify up to 1,000 URL refresh rules, 100 directory refresh rules, or 1 refresh rule that contains regular expressions in each call.
- You can refresh up to 1,000 URLs per minute for each domain name.
Debugging
Authorization information
The following table shows the authorization information corresponding to the API. The authorization information can be used in the Action policy element to grant a RAM user or RAM role the permissions to call this API operation. Description:
- Operation: the value that you can use in the Action element to specify the operation on a resource.
- Access level: the access level of each operation. The levels are read, write, and list.
- Resource type: the type of the resource on which you can authorize the RAM user or the RAM role to perform the operation. Take note of the following items:
- The required resource types are displayed in bold characters.
- If the permissions cannot be granted at the resource level,
All Resourcesis used in the Resource type column of the operation.
- Condition Key: the condition key that is defined by the cloud service.
- Associated operation: other operations that the RAM user or the RAM role must have permissions to perform to complete the operation. To complete the operation, the RAM user or the RAM role must have the permissions to perform the associated operations.
| Operation | Access level | Resource type | Condition key | Associated operation |
|---|---|---|---|---|
| cdn:RefreshObjectCaches | WRITE |
|
| none |
Request parameters
| Parameter | Type | Required | Description | Example |
|---|---|---|---|---|
| ObjectPath | string | Yes | The URLs from which you want to refresh content. Format: Accelerated domain name/Paths or directories of files that you want to refresh. Separate multiple URLs with line feed characters (\n) or a pair of carriage return and line feed characters (\r\n). | http://example.com/image/1.png\nhttp://aliyundoc.com/image/2.png |
| ObjectType | string | No | The type of the object that you want to refresh. Valid values:
If you set the ObjectType parameter to File or Directory, you can view Refresh and prefetch resources to obtain more information. If you set the ObjectType parameter to Regex, you can view Configure URL refresh rules that contain regular expressions to obtain more information. If you set the ObjectType parameter to Directory, the resources in the directory that you want to refresh are marked as expired. You cannot delete the directory. If clients request resources on POPs that are marked as expired, Alibaba Cloud CDN checks whether the resources on your origin server are updated. If resources are updated, Alibaba Cloud CDN retrieves the latest version of the resources and returns the resources to the clients. Otherwise, the origin server returns the 304 status code. | File |
| Force | boolean | No | Specifies whether to refresh resources in a directory if the resources are different from the resources in the same directory in the origin server. Default value: false.
| false |
Response parameters
Examples
Sample success responses
JSONformat
{
"RefreshTaskId": "704222904",
"RequestId": "D61E4801-EAFF-4A63-AAE1-FBF6CE1CFD1C"
}Error codes
| HTTP status code | Error code | Error message |
|---|---|---|
| 400 | SingleRequest.OverLimit | A maximum of 1000 URLs are supported for each request. |
| 400 | InvalidObjectType.Malformed | The specified ObjectType is invalid. |
| 400 | InvalidObjectPath.Malformed | The specified ObjectPath is invalid. |
| 400 | QuotaExceeded.Refresh | Your refresh attempts have exceeded the daily limit. |
| 400 | InvalidExtensiveDomain.ValueNotSupported | The specified ExtensiveDomain is not supported. |
| 400 | QuotaPerMinuteExceeded.Refresh | You tried to refresh too frequently, please try again later. |
| 400 | TooMany.Refresh | The refresh queue is full, please try again later. |
| 429 | TooManyRequests | Too many requests, please try again later |
For a list of error codes, visit the Service error codes.
Change history
| Change time | Summary of changes | Operation | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2023-10-17 | The Error code has changed. The request parameters of the API has changed | see changesets | ||||||||||
|