remi
Cache invalidation policy
How easy is it to define a custom cache invalidation policy for the caching middleware that comes with faraday ? ( FaradayMiddleware::Caching ) .
What could be some good cache invalidation strategies that can be used with 'Her' ?
@teamon did you ever implement something based on "Faraday Http Cache"? If so, could you please provide a simple example so we can add it to the documentation?
Actually I did :) On Her side this is as simple as adding c.user :http_cache to faraday connection middleware. In fact Her does not care (nor it should) about cache at all, it is all done at the faraday's level by using standard HTTP headers based cache. So on client side this is really just a oneliner. On server side take a look at stuff like expires_in
Meh, I read my post again - please forget it. I'll prepare something serious for docs :)
api = Her::API.new
api.setup :url => "http://some.api.com" do |c|
...
c.use :http_cache, Rails.cache, :logger => Rails.logger # from faraday-http-cache gem
c.adapter Faraday.default_adapter
end
class Post
include Her::Model
uses_api api
end
Something like this should be fine
Thank you, @teamon! Think we should change the documentation as this middleware seems to be superior to the one suggested by the README. @remiprev, what do you think?
Any way to force a request when using an API that doesn't specify caching? Basically I want the resource to expire when doing an update or be able to invalidate it manually. I am using faraday middleware for caching. I tried using faraday-http-cache but could not get it to cache anything at all but I assume it would have the same issue if it worked.
@pencil I assume faraday-http-cache is superior if your api provides all required http cache headers, otherwise maybe like @espen replied nothing will be cached, and personally I don't see/recall in a real world api return those http cache headers quite often in my experience.
my suggestion is keep the README as is, but could mention the options of faraday-http-cache if your api also "respects" http caching.
and back to the original issue, i still can't find a good solution to expire a cache manually. maybe could borrow the idea of https://github.com/plataformatec/faraday-http-cache/issues/36#issuecomment-38464461, a hack to faraday-http-cache so can't apply directly here but the idea should be similar, supply a specific parameter(invalidate_cache in the example) that will intercept the response and clear the cache in the middleware layer.
