feat: adding ttl and delete api

lib/groot.ex

@@ -52,9 +52,16 @@ defmodule Groot do
   @doc """
   Sets the value for a register.
   """
-  @spec set(term(), term()) :: :ok
-  def set(key, value) do
-    Storage.set(key, value)
+  @spec set(term(), term(), term() | nil) :: :ok
+  def set(key, value, expires_in \\ nil) do
+    Storage.set(key, value, expires_in)
   end
-end
 
+  @doc """
+  Deletes a register
+  """
+  @spec delete(term()) :: :ok
+  def delete(key) do
+    Storage.delete(key)
+  end
+end

lib/groot/storage.ex

@@ -25,8 +25,19 @@ defmodule Groot.Storage do
   end
 
   # The main api for setting a keys value
-  def set(key, value) do
-    GenServer.call(__MODULE__, {:set, key, value})
+  def set(key, value, expires_in \\ nil) do
+    GenServer.call(__MODULE__, {:set, key, value, expires_in})
+  end
+
+  # The main api for deleting a key
+  def delete(key) do
+    case :ets.lookup(__MODULE__, key) do
+      [] ->
+        :ok
+
+      [{^key, _value}] ->
+        GenServer.call(__MODULE__, {:delete, key})
+    end
   end
 
   # Deletes all keys in the currently connected cluster. This is only
@@ -44,13 +55,26 @@ defmodule Groot.Storage do
     {:ok, %{table: tab, registers: registers}}
   end
 
-  def handle_call({:set, key, value}, _from, data) do
+  def handle_call({:set, key, value, expires_in}, _from, data) do
     registers = Map.update(data.registers, key, Register.new(key, value), fn reg ->
       Register.update(reg, value)
     end)
     :ets.insert(data.table, {key, registers[key].value})
     GenServer.abcast(__MODULE__, {:update_register, registers[key]})
 
+    case expires_in do
+       nil -> :ok
+       _ -> Process.send_after(self(), {:delete, key}, expires_in)
+    end
+
+    {:reply, :ok, %{data | registers: registers}}
+  end
+
+  def handle_call({:delete, key}, _from, data) do
+    registers = Map.delete(data.registers, key)
+    :ets.delete(data.table, key)
+    GenServer.abcast(__MODULE__, {:propagate_delete, key})
+
     {:reply, :ok, %{data | registers: registers}}
   end
 
@@ -79,6 +103,12 @@ defmodule Groot.Storage do
     {:noreply, %{data | registers: new_registers}}
   end
 
+  def handle_cast({:propagate_delete, key}, data) do
+    registers = Map.delete(data.registers, key)
+    :ets.delete(data.table, key)
+    {:noreply, %{data | registers: registers}}
+  end
+
   def handle_info(msg, data) do
     case msg do
       {:nodeup, node} ->
@@ -90,6 +120,10 @@ defmodule Groot.Storage do
         schedule_sync_timeout()
         {:noreply, data}
 
+      {:delete, key} ->
+        registers = delete_record(key, data)
+        {:noreply, %{data | registers: registers}}
+
       _msg ->
         {:noreply, data}
     end
@@ -111,4 +145,11 @@ defmodule Groot.Storage do
     |> Enum.map(fn key -> {key, Register.latest(r1[key], r2[key])} end)
     |> Enum.into(%{})
   end
+
+  defp delete_record(key, data) do
+    registers = Map.delete(data.registers, key)
+    :ets.delete(data.table, key)
+    GenServer.abcast(__MODULE__, {:propagate_delete, key})
+    registers
+  end
 end