Add Pythonx.install_env/0 and Pythonx.install_paths/0 to enable FLAME

lib/pythonx.ex

@@ -8,8 +8,23 @@ defmodule Pythonx do
 
   @moduledoc readme_docs
 
+  defstruct [
+    :python_dl_path,
+    :python_home_path,
+    :python_executable_path,
+    :sys_paths
+  ]
+
   alias Pythonx.Object
 
+  @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(),
+          sys_paths: [String.t()]
+        }
   @type encoder :: (term(), encoder() -> Object.t())
 
   @doc ~s'''
@@ -58,7 +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.
@@ -90,7 +145,7 @@ defmodule Pythonx do
   #     (`sys.path`). Defaults to `[]`.
   #
   @doc false
-  @spec init(String.t(), String.t(), keyword()) :: :ok
+  @spec init(String.t(), String.t(), String.t(), keyword()) :: :ok
   def init(python_dl_path, python_home_path, python_executable_path, opts \\ [])
       when is_binary(python_dl_path) and is_binary(python_home_path)
       when is_binary(python_executable_path) and is_list(opts) do
@@ -111,6 +166,16 @@ defmodule Pythonx do
     Pythonx.NIF.init(python_dl_path, python_home_path, python_executable_path, opts[:sys_paths])
   end
 
+  @spec init(init_state()) :: :ok
+  def init(%__MODULE__{
+        python_dl_path: python_dl_path,
+        python_home_path: python_home_path,
+        python_executable_path: python_executable_path,
+        sys_paths: sys_paths
+      }) do
+    init(python_dl_path, python_home_path, python_executable_path, sys_paths: sys_paths)
+  end
+
   @doc ~S'''
   Evaluates the Python `code`.
 

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()) :: :ok
+  @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])
@@ -95,59 +95,69 @@ defmodule Pythonx.Uv do
 
     root_dir = Path.join(python_install_dir(priv?, opts[:uv_version]), versioned_dir_name)
 
-    case :os.type() do
-      {:win32, _osname} ->
-        # Note that we want the version-specific DLL, rather than the
-        # "forwarder DLL" python3.dll, otherwise symbols cannot be
-        # found directly.
-        python_dl_path =
-          root_dir
-          |> Path.join("python3?*.dll")
-          |> wildcard_one!()
-          |> make_windows_slashes()
-
-        python_home_path = make_windows_slashes(root_dir)
-
-        python_executable_path =
-          project_dir
-          |> Path.join(".venv/Scripts/python.exe")
-          |> make_windows_slashes()
-
-        venv_packages_path =
-          project_dir
-          |> Path.join(".venv/Lib/site-packages")
-          |> make_windows_slashes()
-
-        Pythonx.init(python_dl_path, python_home_path, python_executable_path,
-          sys_paths: [venv_packages_path]
-        )
-
-      {:unix, osname} ->
-        dl_extension =
-          case osname do
-            :darwin -> ".dylib"
-            :linux -> ".so"
-          end
-
-        python_dl_path =
-          root_dir
-          |> Path.join("lib/libpython3.*" <> dl_extension)
-          |> wildcard_one!()
-          |> Path.expand()
-
-        python_home_path = root_dir
-
-        python_executable_path = Path.join(project_dir, ".venv/bin/python")
-
-        venv_packages_path =
-          project_dir
-          |> Path.join(".venv/lib/python3*/site-packages")
-          |> wildcard_one!()
-
-        Pythonx.init(python_dl_path, python_home_path, python_executable_path,
-          sys_paths: [venv_packages_path]
-        )
-    end
+    init_state =
+      case :os.type() do
+        {:win32, _osname} ->
+          # Note that we want the version-specific DLL, rather than the
+          # "forwarder DLL" python3.dll, otherwise symbols cannot be
+          # found directly.
+          python_dl_path =
+            root_dir
+            |> Path.join("python3?*.dll")
+            |> wildcard_one!()
+            |> make_windows_slashes()
+
+          python_home_path = make_windows_slashes(root_dir)
+
+          python_executable_path =
+            project_dir
+            |> Path.join(".venv/Scripts/python.exe")
+            |> make_windows_slashes()
+
+          venv_packages_path =
+            project_dir
+            |> Path.join(".venv/Lib/site-packages")
+            |> make_windows_slashes()
+
+          %Pythonx{
+            python_dl_path: python_dl_path,
+            python_home_path: python_home_path,
+            python_executable_path: python_executable_path,
+            sys_paths: [venv_packages_path]
+          }
+
+        {:unix, osname} ->
+          dl_extension =
+            case osname do
+              :darwin -> ".dylib"
+              :linux -> ".so"
+            end
+
+          python_dl_path =
+            root_dir
+            |> Path.join("lib/libpython3.*" <> dl_extension)
+            |> wildcard_one!()
+            |> Path.expand()
+
+          python_home_path = root_dir
+
+          python_executable_path = Path.join(project_dir, ".venv/bin/python")
+
+          venv_packages_path =
+            project_dir
+            |> Path.join(".venv/lib/python3*/site-packages")
+            |> wildcard_one!()
+
+          %Pythonx{
+            python_dl_path: python_dl_path,
+            python_home_path: python_home_path,
+            python_executable_path: python_executable_path,
+            sys_paths: [venv_packages_path]
+          }
+      end
+
+    Pythonx.init(init_state)
+    init_state
   end
 
   defp wildcard_one!(path) do