Ocelot supports some very rudimentary caching at the moment provider by the CacheManager project. This is an amazing project that is solving a lot of caching problems. We would recommend using this package to cache with Ocelot.
The following example shows how to add CacheManager to Ocelot so that you can do output caching.
First of all, add the following NuGet package:
Install-Package Ocelot.Cache.CacheManager
This will give you access to the Ocelot cache manager extension methods.
The second thing you need to do something like the following to your ConfigureServices
method:
using Ocelot.Cache.CacheManager;
ConfigureServices(services =>
{
services.AddOcelot()
.AddCacheManager(x => x.WithDictionaryHandle());
});
Finally, in order to use caching on a route in your Route configuration add this setting:
"FileCacheOptions": {
"TtlSeconds": 15,
"Region": "europe-central",
"Header": "Authorization"
}
In this example TtlSeconds is set to 15 which means the cache will expire after 15 seconds. The Region represents a region of caching.
Additionally, if a header name is defined in the Header property, that header value is looked up by the key (header name) in the HttpRequest
headers,
and if the header is found, its value will be included in caching key. This causes the cache to become invalid due to the header value changing.
If you look at the example here you can see how the cache manager is setup and then passed into the Ocelot AddCacheManager
configuration method.
You can use any settings supported by the CacheManager package and just pass them in.
Anyway, Ocelot currently supports caching on the URL of the downstream service and setting a TTL in seconds to expire the cache. You can also clear the cache for a region by calling Ocelot's administration API.
If you want to add your own caching method, implement the following interfaces and register them in DI e.g.
services.AddSingleton<IOcelotCache<CachedResponse>, MyCache>();
IOcelotCache<CachedResponse>
this is for output caching.IOcelotCache<FileConfiguration>
this is for caching the file configuration if you are calling something remote to get your config such as Consul.
Please dig into the Ocelot source code to find more. We would really appreciate it if anyone wants to implement Redis, Memcached etc. Please, open a new Show and tell thread in Discussions space of the repository.