Post purge hooks? about cachex

[whitfin]

@lostboy you should realistically be able to receive a { :purge, _opts } message... but I just checked and it appears it's not working. Let me take a quick look at it!

Edit: ha, I knew that this was broken previously but for different reasons... I fixed it but only ever tested it with the internal Stats hook so I totally missed that it wouldn't fire the rest of the hooks. Fix incoming!

[whitfin]

Ok, this is now resolved in the main branch so you can pick it up from here.

The next version will be released on Hex pretty soon, just gotta review a few things. For what it's worth, I always intend master to be stable enough to use (otherwise I keep changes in PR until it is stable), so it should be ok to just point your projects to the GitHub.

For reference, here's the test case I used to make sure the hooks were receiving:

Erlang/OTP 18 [erts-7.3] [source] [64-bit] [smp:8:8] [async-threads:10] [hipe] [kernel-poll:false] [dtrace]

Interactive Elixir (1.2.4) - press Ctrl+C to exit (type h() ENTER for help)
iex(1)> defmodule MyModule.PostPurgeHook do
...(1)>   use Cachex.Hook
...(1)> 
...(1)>   def handle_notify({ :purge, _opts }, state) do
...(1)>     IO.puts("Purge received!")
...(1)>     { :ok, state }
...(1)>   end
...(1)> 
...(1)>   def handle_notify(_action, state) do
...(1)>     { :ok, state }
...(1)>   end
...(1)> end
{:module, MyModule.PostPurgeHook,
 <<70, 79, 82, 49, 0, 0, 13, 96, 66, 69, 65, 77, 69, 120, 68, 99, 0, 0, 2, 221, 131, 104, 2, 100, 0, 14, 101, 108, 105, 120, 105, 114, 95, 100, 111, 99, 115, 95, 118, 49, 108, 0, 0, 0, 4, 104, 2, ...>>,
 {:handle_notify, 2}}
iex(2)> Cachex.start_link([ name: :my_cache, hooks: %Cachex.Hook { module: MyModule.PostPurgeHook, type: :post }, default_ttl: :timer.seconds(3), ttl_interval: :timer.seconds(5) ])
{:ok, #PID<0.149.0>}
iex(3)> Cachex.set(:my_cache, "key", "value")
{:ok, true}
Purge received!
iex(4)> 

If you want to know how many were purged, you need to add results: true to the hook declaration, and change your handler to def handle_notify({ :purge, _opts }, { :ok, count }, state).

I hope this solves your issue, and thank you very much for the kind words 😃 Please let me know if you come across anything else, or have further questions about this!