elixir-in-action/chapter5/stateful_database_server.ex
2020-06-20 13:57:33 -05:00

34 lines
694 B
Elixir

defmodule DatabaseServer do
def start do
spawn(fn ->
connection = :rand.uniform(1000)
loop(connection)
end)
end
defp loop(connection) do
receive do
{:run_query, caller, query_def} ->
send(caller, {:query_result, run_query(connection, query_def)})
end
loop(connection)
end
defp run_query(connection, query_def) do
Process.sleep(2000)
"Connection #{connection}: #{query_def} result"
end
def run_async(server_pid, query_def) do
send(server_pid, {:run_query, self(), query_def})
end
def get_result do
receive do
{:query_result, result} -> result
after
5000 -> {:error, :timeout}
end
end
end