Serving static (non-image) content

Image Serving provides a mechanism to manage non-image contents in catalogs and serve it via a separate context /is/content. The mechanism allows for configuring the TTL for each item separately.

Basic syntax

request	http:// server /is/content[/ catalog / item ][? modifiers ]
server	server_address [: port ]
catalog	Catalog identifier.
item	Static content item ID.
modifiers	command *[& command ]
command	cmdName = value
cmdName	One of the supported command names.
value	Command value.

Command overview

Image Serving supports the following commands at /is/content:

type	Content type filter.
req	req=userdata , req=props , and req=exists only.
cache	Allows disabling client-side caching.

Static content catalogs

Static content catalogs are similar to image catalogs, but support fewer data fields:

Attribute/Data	Notes
catalog::Id	The catalog record identifier for this static content item
catalog::Path	The file path for this content item
catalog::Expiration	The TTL for this content item; attribute::Expiration is used if not specified or if empty
catalog::TimeStamp	File modification time stamp; required when catalog-based validation is enabled with attribute::CacheValidationPolicy
catalog::UserData	Optional metadata associated with this static content item; available to the client with req=userdata
catalog::UserType	Optional data type; can be used to filter requests for static content with the type= command

Filtering static content

This mechanism can help ensure that clients receive only contents appropriate for their needs. Assuming that the static content is tagged with appropriate catalog::UserTypevalues, the client can add the type= command to the request. Image Serving will compare the value provided with the type= command to the value of catalog::UserType and, in case of a mismatch, return an error instead of potentially inappropriate contents.