# Copyright(c) 2015-2023 ACCESS CO., LTD. All rights reserved.
use Croma
defmodule Antikythera.Tmpdir do
alias Antikythera.Context
alias Antikythera.ExecutorPool.Id, as: EPoolId
alias AntikytheraCore.TmpdirTracker
@doc """
Creates a temporary directory which can be used as a working space for the passed function `f`.
This function is basically intended for async jobs which processes large amount of data.
For example, an async job that accumulates data into files and upload them to somewhere
can utilize this function to obtain a temporary working space.
The temporary directory is created before `f` is invoked.
When execution of `f` is finished (either successfully or by exception) the directory is automatically removed.
The function returns the return value of `f`.
Nested calls to this function is not allowed.
Instead you can freely make subdirectories of the temporary directory.
## Example
Antikythera.Tmpdir.make(context, fn tmpdir ->
path = Path.join(tmpdir, "foo")
File.open(path, [:write], fn file ->
IO.write(file, "some data 1")
IO.write(file, "some data 2")
end)
upload_to_object_storage_service("object_key", path)
end)
"""
defun make(context_or_epool_id :: v[EPoolId.t() | Context.t()], f :: (Path.t() -> a)) :: a
when a: any do
epool_id = extract_epool_id(context_or_epool_id)
{:ok, tmpdir} = TmpdirTracker.request(epool_id)
try do
f.(tmpdir)
after
TmpdirTracker.finished()
end
end
defp extract_epool_id(%Context{executor_pool_id: epool_id}), do: epool_id
defp extract_epool_id(epool_id), do: epool_id
end