ShieldedCache

ShieldedCache is a caching module for Elixir.

What makes it special?

It enables a type of CDN Shielding on your cache that allows you to return stale results while simultaneously refreshing your data. This allows you to always return data to your client incredibly fast after the first request is made, while still refreshing data in an async way to keep subsequent requests fresh.

Callbacks

• fetch/1: Executes the cache request and fetches the data
• key/1: Generates a key out of the cache request

Overrideable Functions

• key/1: Generates a key from a cache request
• pre_get_side_effect/1: Creates a side effect before the get happens in the cache
• post_get_side_effect/1: Creates a side effect after the get happens in the cache
• pre_fetch_side_effect/1: Creates a side effect before the fetch happens in the cache
• post_fetch_side_effect/1: Creates a side effect after the fetch happens in the cache
• expired_side_effect/1: Creates a side effect when an expired value is returned from the cache
• first_fetch_side_effect/1: Creates a side effect on the first fetch of the request (when there is no previous value for this request in the cache)
• get_or_fetch_response_time_side_effect/2: Creates a side effect with the response time of the get_or_fetch function for the request
• get_response_time_side_effect/2: Creates a side effect with the response time of the get function for the request
• fetch_response_time_side_effect/2: Creates a side effect with the response time of the fetch function for the request
• hit_side_effect/1: Creates a side effect when a hit happens in the cache
• miss_side_effect/1: Creates a side effect when a miss happens in the cache
• post_fetch_transformation/1: Transforms the result from the fetch in some way when returned to the client
• post_get_transformation/1: Transforms the result from the get in some way when returned to the client
• retry_side_effect/1: Creates a side effect when a retry occurs in the task manager

Defaults

• key/1: Uses the serialize!/1 function to serialize whatever the cache request is into a key for the cache.
• pre_get_side_effect/1: Does nil
• post_get_side_effect/1: Does nil
• pre_fetch_side_effect/1: Does nil
• post_fetch_side_effect/1: Does nil
• expired_side_effect/1: Does nil
• first_fetch_side_effect/1: Does nil
• get_or_fetch_response_time_side_effect/2: Does nil
• get_response_time_side_effect/2: Does nil
• fetch_response_time_side_effect/2: Does nil
• hit_side_effect/1: Does nil
• miss_side_effect/1: Does nil
• post_fetch_transformation/1: Returns the fetch value with no changes
• post_get_transformation/1: Returns the get value with no changes
• retry_side_effect/1: Does nil