Preloading

Preloading means caching the content of a designated URL from the source station to the network nodes. This process eliminates the waiting time when you access the resource for the first time. Preloading is generally used in scenarios that involve the delivery of large files, where it can effectively improve your access experience.

You can configure content prefetching (preloading) for individual files or multiple files. The daily file prefetch count for each subscription is set to 2,000. To adjust this, please contact the development team.

Request

Method	Request URI
POST	https://restapi.cdn.azure.cn/subscriptions/{subscriptionId}/endpoints/{endpointId}/preloads?apiVersion=1.0

URI parameter

Parameter name	Description
subscriptionId	Subscription unique identifier
endpointId	Target node unique identifier

Request header

Request header	Description
x-azurecdn-request-date	Required. Enter the current UTC request time in yyyy-MM-dd hh:mm:ss format.
Authorization	Required. Refer to CDN API signing mechanism for authorization headers.
content-type	Required. application/json

Request body

To add content prefetching, you must specify the parameters. An example JSON file is provided here:

{
  "Files": [
    "http://example.com/pictures/city.png"
  ]
}

Parameter name	Description
Files	When refreshing the file list, the path must be an absolute path. For example:http://example.com/pictures/city.png

Response

A response comprises a status code, response headers, and a response body.

Status code

Status code	Description
202	Indicates that the server has successfully accepted the request.
Other	General response indicating that an error has occurred.

Response header

Response header	Description
X-Correlation-Id	The request's unique identifier, which is used to track request information.

Response body

JSON example for request succeeded:

{
  "Succeeded": true,
  "IsAsync": true,
  "AsyncInfo": {
    "TaskTrackId": "b520c544-ec34-4ac4-86f5-5394363919c3",
    "TaskStatus": "Processing"
  }
}

Parameter name	Description
TaskTrackId	Prefetch operation unique identifier, which can be used to query prefetch progress
TaskStatus	Task status NotSet: State not set Processing: Currently processing Succeeded: Succeeded Failed: Failed

JSON example for request failed:

{
  "Succeeded": false,
  "ErrorInfo": {
    "Type": "MissingAuthorizationHeader",
    "Message": "Missing authorization header."
  }
}

Parameter name	Description
Type	Error type CredentialInvalid: Invalid credentials ParameterMissing: Parameter missing ParameterInvalid: Invalid parameter MissingAuthorizationHeader: Authorization header missing InvalidRequestDateHeader: Invalid request date header MissingRequestDateHeader: Missing request date header AuthorizationHeaderExpired: Authorization header expired InvalidAuthorizationHeader: Invalid authorization header ApiKeyNotFound: API key not found InvalidApiKey: Invalid API key WrongSignature: Wrong signature SubscriptionNotFound: Subscription does not exist EndpointDoesNotBelongToSubscription: Endpoint does not belong to subscription EndpointNotInActiveState: Endpoint not in active state EndpointNotFound: Endpoint does not exist MaliciousItemPathDetected: Malicious item path detected PermissionDenied: Insufficient permissions RequestThrottled: Request throttled
Message	Error information