Caching

API Umbrella provides a standard HTTP caching layer in front of your APIs (using Apache Traffic Server). In order to utilize the cache, your API backend must set HTTP headers on the response. In addition to the standard Cache-Control or Expires HTTP headers, we also support the Surrogate-Control header.

Surrogate-Control

The Surrogate-Control header will only have an effect on the API Umbrella cache. This header will be stripped before the response is delivered publicly.

Surrogate-Control: max-age=(time in seconds)

Cache-Control: s-maxage

The Cache-Control: s-maxage header will be respected by the API Umbrella cache, as well as any other intermediate caches between us and the user.

Cache-Control: s-maxage=(time in seconds)

Cache-Control: max-age

The Cache-Control: max-age header will be respected by the API Umbrella cache, intermediate caching servers, and the user's client.

Cache-Control: max-age=(time in seconds)

Expires

The Expires header will be respected by the API Umbrella cache, intermediate caching servers, and the user's client.

Expires: (HTTP date)