Change to poetry command to export requirements.txt resolving #445

[JoeyC1990]

Hi, Here is the first attempt at fixing the change in the poetry export command.

The change needed was detailed here: https://python-poetry.org/docs/cli/#export

[JoeyC1990]

I have now made this change so hopefully this is ready to be merged

[jimpudar]

I would also love for this to be merged. Currently relying on a workaround for this issue.

[jimpudar]

There's also a corresponding change in the README which needs to be made that references this change.

https://github.com/UnitedIncome/serverless-python-requirements/blob/master/README.md#poetry-support-sparklespencilsparkles

Also, bump - this is a pretty huge issue that prevents anyone using Poetry with this plugin!

[JoeyC1990]

I have updated the readme so this is now ready to push @dschep please can this be merged?

[wozniakty]

Yeah, this is completely blocking my current project from using poetry :(

[miketheman]

This change to require the use of -o flag has broken CI, as the -o flag was not present in poetry version 1.0.0a0 - and a specific test was added in #395 to enable testing against the older version, which has since been overridden here.

There's a few paths forward that I can think of:

1. Reverse the approach taken here and revert to using stdout and redirection.
2. Add poetry version detection logic and try to use redirection if detected.
3. Remove the test for pre-release poetry version, and commit to the stability of version 1.0.0 which supports the -o flag.

I'm leaning towards the final one - this is likely the last bit before we can have a full CI pass again - I've been working through that on #462

[bsamuel-ui]

I agree with dropping support for prerelease poetry.