Built-in esptool flash (via Pythonx)

Optional use built-in esptool install via Pythonx.

Signed-off-by: Peter M <[email protected]>

Author: petermm

lib/esptool_helper.ex

@@ -0,0 +1,24 @@
+defmodule ExAtomVM.EsptoolHelper do
+  @moduledoc """
+  Module for setting up using esptool through Pythonx.
+  """
+
+  @doc """
+  Initializes Python environment with project configuration.
+  We use locked main branch esptool version, pending a stable release 5.x release,
+  as we need the read to memory (instead of only to file) features.
+  """
+  def setup do
+    Application.ensure_all_started(:pythonx)
+
+    Pythonx.uv_init("""
+    [project]
+    name = "project"
+    version = "0.0.0"
+    requires-python = "==3.13.*"
+    dependencies = [
+      "esptool @ git+https://github.com/espressif/esptool.git@6f0d779"
+    ]
+    """)
+  end
+end

lib/mix/tasks/esp32_flash.ex

@@ -59,8 +59,58 @@ defmodule Mix.Tasks.Atomvm.Esp32.Flash do
 
     tool_args = if port == "auto", do: tool_args, else: ["--port", port] ++ tool_args
 
-    tool_full_path = get_esptool_path(idf_path)
-    System.cmd(tool_full_path, tool_args, stderr_to_stdout: true, into: IO.stream(:stdio, 1))
+    case Code.ensure_loaded(Pythonx) do
+      {:module, Pythonx} ->
+        IO.inspect("Flashing using Pythonx installed esptool..")
+        flash_pythonx(tool_args)
+
+      _ ->
+        IO.inspect("Flashing using esptool..")
+        tool_full_path = get_esptool_path(idf_path)
+        System.cmd(tool_full_path, tool_args, stderr_to_stdout: true, into: IO.stream(:stdio, 1))
+    end
+  end
+
+  defp flash_pythonx(tool_args) do
+    # https://github.com/espressif/esptool/blob/master/docs/en/esptool/scripting.rst
+    ExAtomVM.EsptoolHelper.setup()
+
+    {_result, globals} =
+      try do
+        Pythonx.eval(
+          """
+          import esptool
+          import sys
+
+          command = [arg.decode('utf-8') for arg in tool_args]
+
+          def flash_esp():
+              esptool.main(command)
+
+          if __name__ == "__main__":
+              try:
+                  result = flash_esp()
+                  result = True
+              except SystemExit as e:
+                  print(f"SystemExit: {e}")
+                  result = False
+              except Exception as e:
+                  print(f"Warning: {e}")
+                  result = False
+
+          """,
+          %{"tool_args" => tool_args}
+        )
+      rescue
+        e in Pythonx.Error ->
+          IO.inspect("Pythonx error occurred: #{inspect(e)}")
+          exit({:shutdown, 1})
+      end
+
+    case Pythonx.decode(globals["result"]) do
+      true -> exit({:shutdown, 0})
+      false -> exit({:shutdown, 1})
+    end
   end
 
   defp get_esptool_path(<<"">>) do

mix.exs

@@ -21,7 +21,9 @@ defmodule ExAtomVM.MixProject do
   # Run "mix help deps" to learn about dependencies.
   defp deps do
     [
-      {:uf2tool,  "1.1.0"}
+      {:uf2tool, "1.1.0"},
+      {:pythonx, "~> 0.4.0", runtime: false, optional: true}
+
       # {:dep_from_hexpm, "~> 0.3.0"},
       # {:dep_from_git, git: "https://github.com/elixir-lang/my_dep.git", tag: "0.1.0"}
     ]