You can define the operation parameters of an HTTP transaction by configuring an HTTP header. This topic describes how to create an HTTP header.

Background information

HTTP headers are components of the header section of request and response messages that are transmitted over HTTP. HTTP headers define the resources that are being requested and the behavior of clients or servers.

  • The configurations of the HTTP header for a domain name for Content Delivery Network (CDN) affect how a client program responds to all the requests that are destined for the domain name. The client program can be a browser. The header configurations do not affect the cache server.
  • You are not allowed to configure HTTP headers for wildcard domain names.
  1. Log on to the ApsaraVideo VOD console.
  2. In the left-side navigation pane, click Configuration Management.
  3. Choose CDN Configuration > Domain Names.
  4. On the Domain Names page, select the domain name that you want to configure, and click Configure in the Actions column.
  5. Click Cache.
  6. Click the HTTP Header tab. Then, click Add.
  7. Set the Parameter and Value parameters and click OK.

    The following table describes the parameters.

    Parameter Description Example
    Content-Type Specifies the type of the content that is returned to the client program. image
    Cache-Control Specifies the cache policy that the client program follows for requests and responses. no-cache
    Content-Disposition Specifies the default file name that is provided by the client program when the requested content is saved as a file. 123.txt
    Content-Language Specifies the language of the intended audience for the content that is returned to the client program. zh-CN
    Expires Specifies the expiration time of the content that is returned to the client program. Wed, 21 Oct 2015 07:28:00 GMT
    Access-Control-Allow-Origin Specifies the origins from which cross-origin requests are allowed. *
    Note You can enter * to specify all the domain names. You can also enter a full domain name, such as
    Access-Control-Allow-Headers Specifies the fields that are allowed in cross-origin requests. X-Custom-Header
    Access-Control-Allow-Methods Specifies the request methods that are allowed for cross-origin requests. Multiple request methods can be set at the same time, separated by a half-width comma (,). POST,GET
    Note To add the POST and GET methods together, separate them with a comma (,).
    Access-Control-Max-Age Specifies the time to live (TTL) during which the response can be cached for a preflight request that is initiated by the client program for a particular resource. Unit: seconds. 600
    Access-Control-Expose-Headers Specifies the headers that can be exposed as part of the response. Content-Length