68 lines
1.2 KiB
Elixir
68 lines
1.2 KiB
Elixir
defmodule Todo.Database do
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alias Todo.DatabaseWorker
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use GenServer
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@db_folder "./persist"
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@num_of_workers 3
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def start do
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GenServer.start(__MODULE__, nil, name: __MODULE__)
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end
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def store(key, data) do
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GenServer.cast(__MODULE__, {:store, key, data})
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end
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def get(key) do
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GenServer.call(__MODULE__, {:get, key})
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end
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@impl GenServer
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def init(_) do
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File.mkdir_p!(@db_folder)
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{:ok, nil, {:continue, :init}}
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end
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@impl GenServer
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def handle_continue(:init, nil) do
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File.mkdir_p!(@db_folder)
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workers =
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0..(@num_of_workers - 1)
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|> Enum.map(fn i ->
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{:ok, pid} = Todo.DatabaseWorker.start(@db_folder)
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{i, pid}
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end)
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|> Map.new()
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IO.inspect(workers)
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{:noreply, workers}
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end
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@impl GenServer
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def handle_cast({:store, key, data}, workers) do
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workers
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|> get_worker(key)
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|> DatabaseWorker.store(key, data)
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{:noreply, workers}
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end
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@impl GenServer
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def handle_call({:get, key}, _, workers) do
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data =
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workers
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|> get_worker(key)
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|> DatabaseWorker.get(key)
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{:reply, data, workers}
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end
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defp choose_worker(workers, key) do
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id = :erlang.phash2(key, @num_of_workers)
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Map.fetch!(workers, id)
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end
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end
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