Package built by Poetry is missing runtime dependencies - python-packaging

Question

I've been working on a project which so far has just involved building some cloud infrastructure, and now I'm trying to add a CLI to simplify running some AWS Lambdas. Unfortunately both the sdist and wheel packages built using poetry build don't seem to include the dependencies, so I have to manually pip install all of them to run the command. Basically I
run poetry build in the project,
cd "$(mktemp --directory)",
python -m venv .venv,
. .venv/bin/activate,
pip install /path/to/result/of/poetry/build/above, and then
run the new .venv/bin/ executable.
At this point the executable fails, because pip did not install any of the package dependencies. If I pip show PACKAGE the Requires line is empty.
The Poetry manual doesn't seem to specify how to link dependencies to the built package, so what do I have to do instead?
I am using some optional dependencies, could that be interfering with the build process? To be clear, even non-optional dependencies do not show up in the package dependencies.
pyproject.toml:
[build-system]
requires = ["poetry-core>=1.0.0"]
build-backend = "poetry.core.masonry.api"
[tool.black]
line-length = 100
[tool.coverage.report]
exclude_lines = [
'if TYPE_CHECKING:',
'if __name__ == "__main__":',
'pragma: no cover',
]
fail_under = 100
[tool.coverage.run]
branch = true
omit = [
".venv/*",
]
[tool.isort]
case_sensitive = true
line_length = 100
profile = "black"
[tool.mypy]
show_error_codes = true
strict = true
[[tool.mypy.overrides]]
module = [
"jsonschema",
"jsonschema._utils",
"jsonschema.validators",
"multihash",
"pystac",
"pystac.layout",
"pytest_subtests",
"smart_open",
"linz_logger"
]
ignore_missing_imports = true
[tool.poetry]
name = "geostore"
version = "0.1.0"
description = "Central storage, management and access for important geospatial datasets developed by LINZ"
authors = [
"Bill M. Nelson <bmnelson#linz.govt.nz>",
"Daniel Silk <dsilk#linz.govt.nz>",
"Ivan Mincik <ivan.mincik#gmail.com>",
"Mitchell Paff <mpaff#linz.govt.nz>",
"Sandro Santilli <strk#kbt.io>",
"Simon Planzer <splanzer#linz.govt.nz>",
"Victor Engmark <vengmark#linz.govt.nz>",
]
license = "MIT"
readme = "README.md"
homepage = "https://github.com/linz/geostore"
repository = "https://github.com/linz/geostore"
keywords = [
"SpatioTemporal Asset Catalog (STAC)",
"Toitū Te Whenua Land Information New Zealand",
]
classifiers = [
"Development Status :: 4 - Beta",
"Environment :: Console",
"Framework :: AWS CDK",
"Framework :: Pytest",
"Intended Audience :: End Users/Desktop",
"Intended Audience :: Information Technology",
"License :: OSI Approved :: MIT License",
"Natural Language :: English",
"Operating System :: POSIX",
"Programming Language :: Python :: 3.8",
"Topic :: Communications :: File Sharing",
"Topic :: Scientific/Engineering :: GIS",
"Topic :: Utilities",
"Typing :: Typed",
]
[tool.poetry.dependencies]
python = "^3.8"
"aws-cdk.aws-dynamodb" = {version = "*", optional = true}
"aws-cdk.aws-ec2" = {version = "*", optional = true}
"aws-cdk.aws-ecr" = {version = "*", optional = true}
"aws-cdk.aws-ecr_assets" = {version = "*", optional = true}
"aws-cdk.aws-ecs" = {version = "*", optional = true}
"aws-cdk.aws-events" = {version = "*", optional = true}
"aws-cdk.aws-events-targets" = {version = "*", optional = true}
"aws-cdk.aws-iam" = {version = "*", optional = true}
"aws-cdk.aws-lambda" = {version = "*", optional = true}
"aws-cdk.aws-lambda-event-sources" = {version = "*", optional = true}
"aws-cdk.aws-lambda-python" = {version = "*", optional = true}
"aws-cdk.aws-s3" = {version = "*", optional = true}
"aws-cdk.aws-sns" = {version = "*", optional = true}
"aws-cdk.aws-stepfunctions" = {version = "*", optional = true}
"aws-cdk.aws-stepfunctions_tasks" = {version = "*", optional = true}
awscli = {version = "*", optional = true}
boto3 = "*"
cattrs = {version = "*", optional = true}
jsonschema = {version = "*", extras = ["format"], optional = true}
multihash = {version = "*", optional = true}
pynamodb = {version = "*", optional = true}
pystac = {version = "*", optional = true}
slack-sdk = {version = "*", extras = ["models", "webhook"], optional = true}
smart-open = {version = "*", extras = ["s3"], optional = true}
strict-rfc3339 = {optional = true, version = "*"}
typer = "*"
ulid-py = {version = "*", optional = true}
linz-logger = {version = "*", optional = true}
[tool.poetry.dev-dependencies]
black = "*"
boto3-stubs = {version = "*", extras = ["batch", "dynamodb", "events", "lambda", "lambda-python", "s3", "s3control", "sns", "sqs", "ssm", "stepfunctions", "sts"]}
gitlint = "*"
ipdb = "*"
isort = "*"
language-formatters-pre-commit-hooks = "*"
mutmut = "*"
mypy = "*"
pre-commit = "*"
pylint = "*"
pytest = "*"
pytest-randomly = "*"
pytest-socket = "*"
pytest-subtests = "*"
pytest-timeout = "*"
types-pkg-resources = "*"
types-python-dateutil = "*"
types-requests = "*"
types-six = "*"
types-toml = "*"
[tool.poetry.dev-dependencies.coverage]
version = "*"
extras = ["toml"]
[tool.poetry.extras]
cdk = [
"aws-cdk.aws-dynamodb",
"aws-cdk.aws-ec2",
"aws-cdk.aws-ecr",
"aws-cdk.aws-ecr_assets",
"aws-cdk.aws-ecs",
"aws-cdk.aws-events",
"aws-cdk.aws-events-targets",
"aws-cdk.aws-iam",
"aws-cdk.aws-lambda",
"aws-cdk.aws-lambda-event-sources",
"aws-cdk.aws-lambda-python",
"aws-cdk.aws-s3",
"aws-cdk.aws-sns",
"aws-cdk.aws-stepfunctions",
"aws-cdk.aws-stepfunctions_tasks",
"awscli",
"cattrs",
]
check_files_checksums = [
"boto3",
"linz-logger",
"multihash",
"pynamodb",
]
check_stac_metadata = [
"boto3",
"jsonschema",
"linz-logger",
"pynamodb",
"strict-rfc3339",
]
cli = [
"boto3",
"typer",
]
content_iterator = [
"jsonschema",
"linz-logger",
"pynamodb",
]
datasets = [
"boto3",
"jsonschema",
"linz-logger",
"pynamodb",
"pystac",
"ulid-py",
]
dataset_versions = [
"jsonschema",
"linz-logger",
"pynamodb",
"ulid-py",
]
import_asset_file = [
"boto3",
"linz-logger",
"smart-open",
]
import_dataset = [
"boto3",
"jsonschema",
"linz-logger",
"pynamodb",
"smart-open",
"ulid-py",
]
import_metadata_file = [
"boto3",
"linz-logger",
]
import_status = [
"boto3",
"jsonschema",
"linz-logger",
"pynamodb",
]
notify_status_update = [
"boto3",
"jsonschema",
"linz-logger",
"pynamodb",
"slack-sdk"
]
populate_catalog = [
"boto3",
"jsonschema",
"linz-logger",
"pystac",
]
update_dataset_catalog = [
"boto3",
"jsonschema",
"linz-logger",
"pynamodb",
"ulid-py"
]
upload_status = [
"boto3",
"jsonschema",
"linz-logger",
"pynamodb",
]
validation_summary = [
"jsonschema",
"linz-logger",
"pynamodb",
]
[tool.poetry.scripts]
geostore = "geostore.cli:app"
[tool.pylint.MASTER]
disable = [
"duplicate-code",
"missing-class-docstring",
"missing-function-docstring",
"missing-module-docstring",
]
load-plugins = [
"pylint.extensions.mccabe",
]
max-complexity = 6
[tool.pytest.ini_options]
addopts = "--randomly-dont-reset-seed"
markers = [
"infrastructure: requires a deployed infrastructure",
]
python_functions = "should_*"
testpaths = [
"tests"
]
As you can see the boto3 and typer runtime dependencies are not optional, so I'd expect to see them in poetry show geostore.

Answer 1

This appears to be a bug in Poetry. Or at least it's not clear from the documentation what the expected behavior would be in a case such as yours.
In your pyproject.toml, you specify two dependencies as required in this section:
[tool.poetry.dependencies]
…
awscli = {version = "*", optional = true}
boto3 = "*"
…
typer = "*"
…
So, as opposed to awscli among many others, boto3 and typer should be required because the optional attribute is not set and defaults to false. But you also list the two required dependencies as "extras" in this section:
[tool.poetry.extras]
…
cli = [
"boto3",
"typer",
]
…
Poetry takes that to mean that they are in fact optional, not required. Which makes sense, in a way, because extras are effectively optional. If you inspect the .whl wheel file built by Poetry (it's just a zip archive), specifically the METADATA file in it (which is what Pip refers to when installing the package), then it contains this line:
Requires-Dist: typer; extra == "cli"
So that dependency is in fact optional: It will only get installed if users ask for it explicitly with pip install geostore[cli].
The solution then is simple: Remove all references to the required dependencies from the extras section. They are not needed there anyway.
The Poetry documentation is in fact not very clear on what optional really signifies. That attribute is (currently) only briefly mentioned in the section on the pyproject.toml file. One could also argue that if optional is false, then the extras section should not override that value.