From afb2ea67fe27c169ec21f8f16039084803e12b2a Mon Sep 17 00:00:00 2001
From: ducoterra <git@ducoterra.net>
Date: Mon, 10 Feb 2025 17:29:02 -0500
Subject: [PATCH] initial python serial repl

---
 .python-version |  1 +
 pyproject.toml  |  9 ++++++
 serial_repl.py  | 82 +++++++++++++++++++++++++++++++++++++++++++++++++
 uv.lock         | 22 +++++++++++++
 4 files changed, 114 insertions(+)
 create mode 100644 .python-version
 create mode 100644 pyproject.toml
 create mode 100644 serial_repl.py
 create mode 100644 uv.lock

diff --git a/.python-version b/.python-version
new file mode 100644
index 0000000..e4fba21
--- /dev/null
+++ b/.python-version
@@ -0,0 +1 @@
+3.12
diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 0000000..b651cd7
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,9 @@
+[project]
+name = "off-grid-lora"
+version = "0.1.0"
+description = "Add your description here"
+readme = "README.md"
+requires-python = ">=3.12"
+dependencies = [
+    "pyserial>=3.5",
+]
diff --git a/serial_repl.py b/serial_repl.py
new file mode 100644
index 0000000..c7a22fa
--- /dev/null
+++ b/serial_repl.py
@@ -0,0 +1,82 @@
+import serial
+import threading
+from time import sleep
+
+class SelfHealingSerial():
+    """A wrapper class for pyserial's Serial class
+
+    This reimplements the basic Serial functions but wraps them in _reestablish_and_retry.
+    This attempts a reconnect if the arduino is unplugged or otherwise unavailable.
+
+    Also this has defaults that work with the Adafruit M0 LoRa feather.
+    """
+    def __init__(self, path: str = '/dev/ttyACM0', baudrate: int = 115200, timeout: int = 2):
+        self._path = path
+        self._baudrate = baudrate
+        self._timeout = timeout
+        self._connection = None
+        self._waiting_response = False
+
+    def _establish_connection(self):
+        """Connects to the feather
+        """
+        self._connection = serial.Serial(self._path, self._baudrate, timeout=self._timeout)
+
+    def _reestablish_and_retry(func):
+        """If disconnect, keep trying every second
+
+        We know if there's a disconnect when the attempted function fails.
+        """
+        def wrapper(self: "SelfHealingSerial", *args, **kwargs):
+            while True:
+                try:
+                    if not self._connection:
+                        self._establish_connection()
+                    return func(self, *args, **kwargs)
+                except (IOError, serial.serialutil.SerialException):
+                    print("Connection failed.")
+                    sleep(1)
+                    print("Reestablishing connection.")
+                    self._connection = False
+        return wrapper
+
+    @_reestablish_and_retry
+    def read_all(self):
+        """Read all data from the serial port
+        """
+        return self._connection.read_all()
+
+    @_reestablish_and_retry
+    def write(self, bytestring: bytes):
+        """Write to the serial port
+        """
+        self._waiting_response = True
+        return self._connection.write(bytestring)
+
+def print_serial(serial_obj: SelfHealingSerial):
+    """Check for new serial output and print it to the terminal
+    """
+    while True:
+        line = serial_obj.read_all()
+        if line:
+            serial_obj._waiting_response = False
+            print("\n" + line.decode() + "\n>>>", end="")
+
+def write_serial(serial_obj: SelfHealingSerial):
+    """If we're not waiting for a response, write data to the serial port, then wait for a response.
+    """
+    while True:
+        if not serial_obj._waiting_response:
+            send_string = input("")
+            if send_string and send_string != '\n' and send_string != '\r\n':
+                serial_obj.write(send_string.encode('utf-8'))
+        else:
+            sleep(1)
+
+if __name__ == "__main__":
+    connection: SelfHealingSerial = SelfHealingSerial('/dev/ttyACM0', 115200, timeout=1)
+    listen_thread = threading.Thread(target=print_serial, args=(connection,))
+    listen_thread.start()
+    print(">>> ", end="")
+
+    write_serial(connection)
\ No newline at end of file
diff --git a/uv.lock b/uv.lock
new file mode 100644
index 0000000..25ca698
--- /dev/null
+++ b/uv.lock
@@ -0,0 +1,22 @@
+version = 1
+requires-python = ">=3.12"
+
+[[package]]
+name = "off-grid-lora"
+version = "0.1.0"
+source = { virtual = "." }
+dependencies = [
+    { name = "pyserial" },
+]
+
+[package.metadata]
+requires-dist = [{ name = "pyserial", specifier = ">=3.5" }]
+
+[[package]]
+name = "pyserial"
+version = "3.5"
+source = { registry = "https://pypi.org/simple" }
+sdist = { url = "https://files.pythonhosted.org/packages/1e/7d/ae3f0a63f41e4d2f6cb66a5b57197850f919f59e558159a4dd3a818f5082/pyserial-3.5.tar.gz", hash = "sha256:3c77e014170dfffbd816e6ffc205e9842efb10be9f58ec16d3e8675b4925cddb", size = 159125 }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/07/bc/587a445451b253b285629263eb51c2d8e9bcea4fc97826266d186f96f558/pyserial-3.5-py2.py3-none-any.whl", hash = "sha256:c4451db6ba391ca6ca299fb3ec7bae67a5c55dde170964c7a14ceefec02f2cf0", size = 90585 },
+]