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.
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. |
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 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 |
This mechanism can help ensure that clients receive only contents appropriate for their needs. Assuming that the static content is tagged with appropriate catalog::UserType
values, 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.
type= , req=, Image Catalog Reference