Hydrating Cache accepts CRON intervals

lib/archethic/oracle_chain/services/hydrating_cache.ex

@@ -7,6 +7,7 @@ defmodule Archethic.OracleChain.Services.HydratingCache do
   """
   use GenServer
 
+  alias Archethic.Utils
   require Logger
 
   defmodule State do
@@ -15,6 +16,7 @@ defmodule Archethic.OracleChain.Services.HydratingCache do
       :mfa,
       :ttl,
       :ttl_timer,
+      # refresh_interval :: Int | CronInterval
       :refresh_interval,
       :value,
       :hydrating_task,
@@ -108,7 +110,7 @@ defmodule Archethic.OracleChain.Services.HydratingCache do
       end
 
     # start a new hydrate timer
-    hydrating_timer = Process.send_after(self(), :hydrate, refresh_interval)
+    hydrating_timer = Process.send_after(self(), :hydrate, next_tick_in_seconds(refresh_interval))
 
     new_state = %{
       state
@@ -132,4 +134,12 @@ defmodule Archethic.OracleChain.Services.HydratingCache do
   def handle_info(:discard_value, state) do
     {:noreply, %State{state | value: nil, ttl_timer: nil}}
   end
+
+  defp next_tick_in_seconds(refresh_interval) do
+    if is_binary(refresh_interval) do
+      Utils.time_offset(refresh_interval) * 1000
+    else
+      refresh_interval
+    end
+  end
 end

test/archethic/oracle_chain/services/hydrating_cache_test.exs

@@ -36,6 +36,25 @@ defmodule ArchethicCache.OracleChain.Services.HydratingCacheTest do
     assert date != date2
   end
 
+  test "should work with cron interval" do
+    {:ok, pid} =
+      HydratingCache.start_link(
+        mfa: {DateTime, :utc_now, []},
+        refresh_interval: "* * * * *",
+        ttl: :infinity
+      )
+
+    :erlang.trace(pid, true, [:receive])
+    assert_receive {:trace, ^pid, :receive, :hydrate}
+    Process.sleep(1)
+    {:ok, date} = HydratingCache.get(pid)
+
+    # minimum interval is 1s
+    Process.sleep(1005)
+    {:ok, date2} = HydratingCache.get(pid)
+    assert date != date2
+  end
+
   test "should discard the value after the ttl is reached" do
     {:ok, pid} =
       HydratingCache.start_link(