Preloading

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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