store init_state as persistent_term and add flame_env() to retrieve it

Author: mruoss

lib/pythonx.ex

@@ -17,7 +17,9 @@ defmodule Pythonx do
 
   alias Pythonx.Object
 
-  @type python_config :: %__MODULE__{
+  @install_env_name "PYTHONX_FLAME_INIT_STATE"
+
+  @type init_state :: %__MODULE__{
           python_dl_path: String.t(),
           python_home_path: String.t(),
           python_executable_path: String.t(),
@@ -71,7 +73,47 @@ defmodule Pythonx do
     opts = Keyword.validate!(opts, force: false, uv_version: Pythonx.Uv.default_uv_version())
 
     Pythonx.Uv.fetch(pyproject_toml, false, opts)
-    Pythonx.Uv.init(pyproject_toml, false, Keyword.take(opts, [:uv_version]))
+    init_state = Pythonx.Uv.init(pyproject_toml, false, Keyword.take(opts, [:uv_version]))
+    :persistent_term.put(:pythonx_init_state, init_state)
+  end
+
+  @spec init_state() :: init_state()
+  defp init_state() do
+    :persistent_term.get(:pythonx_init_state)
+  end
+
+  @doc ~s'''
+  Fetches the pythonx init state from the system environment variable.
+  '''
+  @spec init_state_from_env() :: String.t() | nil
+  def init_state_from_env(), do: System.get_env(@install_env_name)
+
+  @doc ~s'''
+  Returns a map containing the environment variables required to initialize Pythonx.
+  '''
+  @spec install_env() :: map()
+  def install_env() do
+    init_state =
+      init_state()
+      |> :erlang.term_to_binary()
+      |> Base.encode64()
+
+    %{name: @install_env_name, value: init_state}
+  end
+
+  @doc ~s'''
+  Returns a list of paths to copy to the flame runner.
+  '''
+  @spec install_paths() :: list(String.t())
+  def install_paths() do
+    init_state = init_state()
+
+    [
+      init_state.python_dl_path,
+      init_state.python_executable_path
+    ] ++
+      init_state.sys_paths ++
+      Path.wildcard(Path.join(init_state.python_home_path, "**"), match_dot: true)
   end
 
   # Initializes the Python interpreter.
@@ -124,7 +166,7 @@ defmodule Pythonx do
     Pythonx.NIF.init(python_dl_path, python_home_path, python_executable_path, opts[:sys_paths])
   end
 
-  @spec init(python_config()) :: :ok
+  @spec init(init_state()) :: :ok
   def init(%__MODULE__{
         python_dl_path: python_dl_path,
         python_home_path: python_home_path,

lib/pythonx/application.ex

@@ -31,7 +31,18 @@ defmodule Pythonx.Application do
     Pythonx.Uv.fetch(pyproject_toml, true, opts)
     defp maybe_uv_init(), do: Pythonx.Uv.init(unquote(pyproject_toml), true, unquote(opts))
   else
-    defp maybe_uv_init(), do: :noop
+    defp maybe_uv_init() do
+      case Pythonx.init_state_from_env() do
+        nil ->
+          :noop
+
+        init_state_env_value ->
+          init_state_env_value
+          |> Base.decode64!()
+          |> :erlang.binary_to_term()
+          |> Pythonx.init()
+      end
+    end
   end
 
   defp enable_sigchld() do

lib/pythonx/uv.ex

@@ -66,7 +66,7 @@ defmodule Pythonx.Uv do
   Initializes the interpreter using Python and dependencies previously
   fetched by `fetch/3`.
   """
-  @spec init(String.t(), boolean()) :: Pythonx.python_config()
+  @spec init(String.t(), boolean()) :: Pythonx.init_state()
   def init(pyproject_toml, priv?, opts \\ []) do
     opts = Keyword.validate!(opts, uv_version: default_uv_version())
     project_dir = project_dir(pyproject_toml, priv?, opts[:uv_version])
@@ -95,7 +95,7 @@ defmodule Pythonx.Uv do
 
     root_dir = Path.join(python_install_dir(priv?, opts[:uv_version]), versioned_dir_name)
 
-    python_config =
+    init_state =
       case :os.type() do
         {:win32, _osname} ->
           # Note that we want the version-specific DLL, rather than the
@@ -156,8 +156,8 @@ defmodule Pythonx.Uv do
           }
       end
 
-    Pythonx.init(python_config)
-    python_config
+    Pythonx.init(init_state)
+    init_state
   end
 
   defp wildcard_one!(path) do