envvar not picked up in AWS Lambda context

[zopyx]

First Check

• I added a very descriptive title to this issue.
• I used the GitHub search to find a similar issue and didn't find it.
• I searched the Typer documentation, with the integrated search.
• I already searched in Google "How to X in Typer" and didn't find any information.
• I already read and followed all the tutorial in the docs and didn't find an answer.
• I already checked if it is not related to Typer but to Click.

Commit to Help

• I commit to help with one of those options 👆

Example Code

database: str = typer.Option(
        ...,
        help="URL for Postgres sync database (e.g. postgresqlext://user:pw@localhost/mydb)",
        envvar="SYNC_DATABASE",
    )

Description

I havr a main() method with a parameter database as documented above. It will pick up its configuration from the given environment variable SYNC_DATABASE. This works perfectly from the commandline.

Now, I want to use the same application code with main() as entry point from within an AWS Lambda function.
The related environment variable is correctly set through the AWS Lambda environment (checked by using logger messages).
So SYNC_DATABASE is correctly available for the Python process.

The Lambda handler invokes typer.run(main).

However, the database parameter is always set to OptionInfo rather than the value of the configured environment variable.

Expected behavior: database should have the value of the env var SYNC_DATABASE.

Operating System

Linux

Operating System Details

AWS Lambda

Typer Version

0.4.2

Python Version

3.9

Additional Context

No response

[zarch]

@zopyx did you export your variables?

I have a similar issue that I think is related to this.
I'm on debian testing, I'm in a dedicated and activated virtualenv.

The python code is:

# file: test_typer.py
import typer
from typing_extensions import Annotated

arg_database: str = typer.Option(
        ...,
        help="URL for Postgres sync database (e.g. postgresqlext://user:pw@localhost/mydb)",
        envvar="SYNC_DATABASE",
    )


def main(database: Annotated[str, arg_database]):
    print(f"DATABASE: {database}")


if __name__ == "__main__":
    typer.run(main)

I prepared the environment in with the following commands:

🐍 v3.12.1 (.venv)
❯ echo "SYNC_DATABASE='my_nice_db'\n" > myenv

🐍 v3.12.1 (.venv)
❯ cat myenv
SYNC_DATABASE='my_nice_db'

🐍 v3.12.1 (.venv)
❯ source myenv

syngw on  bus.nats [!+?⇡] is 📦 v0.0.1 via 🐍 v3.12.1 (.venv)
❯ echo $SYNC_DATABASE
my_nice_db

Now I tested the code with:

🐍 v3.12.1 (.venv)
❯ python test_typer.py --database="my_nice_db"
DATABASE: my_nice_db

🐍 v3.12.1 (.venv)
❯ echo $SYNC_DATABASE
my_nice_db

 🐍 v3.12.1 (.venv)
❯ python test_typer.py
Usage: test_typer.py [OPTIONS]
Try 'test_typer.py --help' for help.
╭─ Error ────────────────────────────────────────────────╮
│ Missing option '--database'.                           │
╰────────────────────────────────────────────────────────╯

🐍 v3.12.1 (.venv)
❯ SYNC_DATABASE=$SYNC_DATABASE python test_typer.py
DATABASE: my_nice_db

So from the above test the command seems to take the environment variable only when passed explicitly from the command line, probably this is due that the variables are available only at process level and are not pass through the processes. Exporting the variable fixed my issue!

🐍 v3.12.1 (.venv)
❯ export SYNC_DATABASE="my_nice_db"

 🐍 v3.12.1 (.venv)
❯ python test_typer.py
DATABASE: my_nice_db

I believe that this should fix also your issue.

[zopyx]

LOL...shall I remember what I did two years ago?