HTTP In Memory Response Cache

[michal-ciechan]

We need an HTTP client that leverages ASP.NET Core Response and/or Output caching (which uses relatively standard HTTP caching headers).

Would this be something you would accept into Refit or should we build on top of/to the side of Refit?

We are initially looking to support the If-Modified-Since caching mechanism, in short:

• only affect certain requests (by default same ones as ASP.NE Core OutputCaching Default output caching policy)
• For requests in question use an in-memory cache (probably Microsoft.Extensions.Caching.Memory.MemoryCache)
• send a request with If-Modified-Since for requests in question where we have a cached entry
• If 304 is returned, return cached response, otherwise store the result adhering to cache headers, and return it.

[JeremyBP]

Hi,

Just to let you know that I just pushed Apizr v6.1.0 which includes your response caching feature on top of Refit.
You just have to pick the new SetByHeader cache mode to let the server control the client cache mode and lifetime, depending on response headers such as Cache-Control, Expires, ETag/If-None-Match and Last-Modified/If-Modified-Since.
More info on Apizr documentation.

Let me know if it suits your needs or if I forgot something :)

[glennawatson]

HTTP caching is out of scope for Refit's core - Refit is a thin typed wrapper over HttpClient and intentionally stays out of the response pipeline beyond serialization. The right place for conditional-request / 304 / If-Modified-Since handling is a DelegatingHandler, which composes cleanly with any Refit client.

As JeremyBP noted, this is already available built on top of Refit: Apizr v6.1.0+ ships exactly this via its SetByHeader cache mode, honoring Cache-Control, Expires, ETag/If-None-Match, and Last-Modified/If-Modified-Since. See https://www.apizr.net/articles/config_datacaching.html

Recommendation: use Apizr, or write a small caching DelegatingHandler (backed by IMemoryCache) and plug it into your Refit client's handler chain. Closing as addressed by existing tooling.