What is the problem?

We're starting to use PythonFunction from @aws-cdk/aws-lambda-python-alpha with poetry (a pyproject.toml and poetry.lock file in the directory specified by entry), and it works pretty well, thanks.

However, the exported requirements.txt is written to the asset input volume directory, meaning it ends up written to the entry directory next to pyproject.toml, which is a bit unexpected. This requires configuring .gitignore correctly, and also may impact the fingerprinting procedure.

(Looking at the code there, this likely applies to pipenv too)

Reproduction Steps

import * as cdk from 'aws-cdk-lib';
import * as lambdaPython from '@aws-cdk/aws-lambda-python-alpha';

export const app = new cdk.App();
const stack = new cdk.Stack(app, 'Stack', {});

new lambdaPython.PythonFunction(stack, 'Func', {
  entry: 'entry',
  index: 'entry/__init__.py',
  runtime: cdk.aws_lambda.Runtime.PYTHON_3_9,
});

Directory tree of entry (before running anything):

entry
├── entry
│   └── __init__.py
├── poetry.lock
└── pyproject.toml

poetry.lock:

package = []

[metadata]
lock-version = "1.1"
python-versions = "*"
content-hash = "115cf985d932e9bf5f540555bbdd75decbb62cac81e399375fc19f6277f8c1d8"

[metadata.files]

pyproject.toml:

[tool.poetry]
name = "entry"
version = "0.1.0"
description = ""
authors = []

[build-system]
requires = ["poetry-core>=1.0.0"]
build-backend = "poetry.core.masonry.api"

__init__.py: empty

What did you expect to happen?

Temporary files shouldn't be written to disk (or at least, not intermixed with real source). For instance, the generated requirements.txt could be placed into any other directory in the docker image and this probably won't occur.

What actually happened?

After running cdk synth, a (empty, in this case) requirements.txt file appears:

entry
├── entry
│   └── __init__.py
├── poetry.lock
├── pyproject.toml
└── requirements.txt

CDK CLI Version

2.14.0 (build 762d71b)

Framework Version

No response

Node.js Version

v14.17.5

OS

macOS

Language

Typescript

Language Version

TypeScript 4.1.6

Other information

No response