OTA password in separate file

1

I would like to put the ota password in a separate file that is not uploaded to GitHub. So far I’ve managed to put the password in the code using a “pre” python script:

Import ("env")
import os

password = ""

with open("ota_password.txt") as f:
  password = f.readline()

env.Append(CPPDEFINES=[("OTA_PASSWORD", "\\\"" + password + "\\\"")])

But now the password should also be replaced in the platformio.ini upload_flags. I’ve read all the documentation I found but so far I found nothing that worked. Is there a way to access the CPPDEFINES variables in platformio.ini or is there another way to pass variables from the python script to the ini file?

Here is my platformio.ini file:

[platformio]
default_envs = release

[env]
platform = espressif32
board = featheresp32
framework = arduino
board_build.partitions = min_spiffs.csv
extra_scripts = pre:ota_password.py
monitor_speed=115200

[env:release]
upload_protocol = espota
upload_port = 172.17.128.30
upload_flags =
  --port=8266
  --auth=${sysenv.OTA_PASSWORD}
build_flags = -DDOUBLERESETDETECTOR_DEBUG=false -DRC_SWITCH_DEBUG=false

[env:debug]
build_flags = -DDOUBLERESETDETECTOR_DEBUG=true -DRC_SWITCH_DEBUG=true
2

You are already telling PlatformIO to read the OTA_PASSWORD variable from the system environment variables here – have you tried doing a import os and os.environ["OTA_PASSWORD"] = password in your script?

You can also always fallback to a custom upload method as outlined in the docs. In the upload logic, you can basically duplicate the pre-existing logic and just add your --auth param.

1 Like
3

Yes I’ve already tried setting the environment variable with os.environ["OTA_PASSWORD"] = password, but for some reason this doesn’t work.

I also found the custom upload method, but I want to be able to easily switch from debug with usb upload to release with ota upload. Is this also somehow possible with this method?

4

I’ll try myself with the environment variable way… maybe it creates the variale in a different shell session than the one the uplaod takes place.

1 Like
5

I work with Visual Studio Code on a Mac. Maybe there is something different?

Is it maybe possible to read the parameters from the platformio.ini file in the python script? This way I would be able to get the default_envs config and only add the upload method if the release build is configured.

6

Just throwing this out there… extra_configs. Never used it myself, but it lets you define extra configurations in a seperate file. In a pinch, defining an env with your password as a build flag, and then importing that env via extendsand maybe some other glue might do the trick? Another possibility anyway.

7

I found a different solution in the meantime. I now simply check the PIOENV variable in the Python script to determine if debug or release is selected. Here is my Python script:

Import ("env")
import os.path

#print(env.Dump())

if os.path.isfile("ota.txt"):
  lines = open("ota.txt","r").read().splitlines()

  port = lines[0]
  password = lines[1]

  env.Append(CPPDEFINES=[("OTA_PASSWORD", "\\\"" + password + "\\\"")])

  if env["PIOENV"] == "release":
    env.Replace(
        UPLOAD_PROTOCOL="espota",
        UPLOAD_PORT=port,
        UPLOAD_FLAGS=["--port=8266", "--auth=" + password],
    )
else:
  env.Append(CPPDEFINES=[("OTA_PASSWORD", "\\\"defaultPassword\\\"")])
1 Like
8

In case this is helpful to anyone in the future, my approach has been to read the environment variable directly from the platform.ini file.

The following assumes that you have a .env file at the project root with a variable named PW in the form of PW=yourPassword:

upload_flags =
	--auth=`awk '/^PW=/ {sub(/PW=/, ""); print;}' .env`

The /^PW=/ tells awk to only match lines that begin with PW=.

The sub(/PW=/, ""); tells awk to remove the text PW=, as it isn’t part of the password.

And finally, the print simply prints what remains (ie the actual password), so it gets set as the value for --auth.

I’m sure there are hundreds of ways to approach this, but I like that this is a simple one liner.