#21161 Python PEX Binary can't resolve internal dependencies New discussion created by delucca Sure! Here’s a more streamlined and clear version of the question: * * * Hi everyone! I'm new to Pants and really enjoying it. I've set up my application, which has two main directories:

apps

and

libs

. Here’s the structure:

.
├── apps
│   └── api
└── libs
    ├── common
    ├── config
    ├── logging
    └── storage

My

pyproject.toml

file looks like this:

[project]
name = "my_project"
version = "0.1.0"
dependencies = [
    "fastapi>=0.11.0",
    "uvicorn>=0.30.1",
    "loguru>=0.7.2",
    "google-cloud-storage>=2.17.0",
    "google-auth>=2.31.0",
    "msgpack>=1.0.8",
    "dependency-injector>=4.41.0",
    "typing-extensions>=4.12.2"
]

[tool.pants]
pants_version = "2.21.0"

[tool.pants.backend.python]
interpreter_constraints = ["==3.11.*"]

[project.optional-dependencies]
dev = [
    "pytest>=8.2.2",
    "pytest-docker>=3.1.1",
    "httpx>=0.27.0",
]

My root

BUILD

file (located at the root of the repo) is:

python_requirements(
    name="reqs",
    source="pyproject.toml",
)

python_test_utils(
    name="test_utils",
    sources=["conftest.py", "tests/utils.py"],
    dependencies=[":test_files"],
)

resources(
    name="test_files",
    sources=[
        "docker-compose.yaml",
    ],
)

The

BUILD

file for

apps/api

is:

python_source(
    name="dev",
    source="src/serve.py",
    restartable=True,
)

python_sources(
    name="api",
    sources=["**/*.py"],
)

python_tests(
    name="tests",
    sources=["tests/**/test_*.py"],
)

python_test_utils(
    name="test_utils",
    sources=["tests/conftest.py"],
)

pex_binary(
    name="prod",
    entry_point="api:src/serve.py",
    dependencies=[":api"],
)

The

BUILD

file for

libs/logging

is:

python_sources(
    name="logging",
    sources=["**/*.py"],
)

python_tests(
    name="tests",
    sources=["tests/**/test_*.py"],
)

python_test_utils(
    name="test_utils",
    sources=["tests/conftest.py"],
)

The Issue: When I run

pants run apps/api:dev

, everything works fine, and my server starts without any issues. However, when I try to package it for distribution using

pants package apps/api:prod

, it builds a file under

dist

, but running

python dist/apps.api/prod.pex

results in the following error:

Traceback (most recent call last):
  File "/home/user/.pyenv/versions/3.10.13/lib/python3.10/runpy.py", line 196, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "/home/user/.pyenv/versions/3.10.13/lib/python3.10/runpy.py", line 86, in _run_code
    exec(code, run_globals)
  File "/home/user/.pex/unzipped_pexes/bcf78f6358b27c64889df89320647e5714c84b7c/__main__.py", line 105, in <module>
    from pex.pex_bootstrapper import bootstrap_pex
  File "/home/user/.pex/unzipped_pexes/bcf78f6358b27c64889df89320647e5714c84b7c/.bootstrap/pex/pex_bootstrapper.py", line 13, in <module>
    from pex.environment import ResolveError
  File "/home/user/.pex/unzipped_pexes/bcf78f6358b27c64889df89320647e5714c84b7c/.bootstrap/pex/environment.py", line 12, in <module>
    from pex import dist_metadata, pex_warnings, targets
  File "/home/user/.pex/unzipped_pexes/bcf78f6358b27c64889df89320647e5714c84b7c/.bootstrap/pex/dist_metadata.py", line 27, in <module>
    from pex.pep_440 import Version
  File "/home/user/.pex/unzipped_pexes/bcf78f6358b27c64889df89320647e5714c84b7c/.bootstrap/pex/pep_440.py", line 19, in <module>
    from pex.third_party.packaging import utils as packaging_utils
  File "/home/user/.pex/unzipped_pexes/bcf78f6358b27c64889df89320647e5714c84b7c/.bootstrap/pex/vendor/_vendored/packaging_23_1/packaging/utils.py", line 8, in <module>
    from .tags import Tag, parse_tag
  File "/home/user/.pex/unzipped_pexes/bcf78f6358b27c64889df89320647e5714c84b7c/.bootstrap/pex/vendor/_vendored/packaging_23_1/packaging/tags.py", line 5, in <module>
    import logging
  File "/home/user/src/project/libs/logging/__init__.py", line 1, in <module>
    from loguru._logger import Logger
ModuleNotFoundError: No module named 'loguru'

It seems like PEX can't resolve the

loguru

dependency, which is only used in

libs/logging

. What am I missing? How can I ensure all dependencies are correctly packaged? Thanks in advance for your help! pantsbuild/pants