Output from pants peek, for a lambda built with python & poetry. No details of the python runtime anywhere in `pants peek` output 😔

01-pants.toml

[GLOBAL]
pants_version = "2.27.0"

backend_packages = [
  "pants.backend.build_files.fmt.black",
  "pants.backend.build_files.fmt.ruff",

  "pants.backend.python.lint.black",
  "pants.backend.python.lint.pyupgrade",
  "pants.backend.experimental.python.lint.ruff.check",
  "pants.backend.experimental.python.lint.ruff.format",
  # "pants.backend.python.lint.bandit", # TODO: figure out how to disable B101 for tests

  "pants.backend.awslambda.python",
  "pants.backend.python",
  
  "pants.backend.experimental.adhoc",
]

[python]
interpreter_constraints = ["==3.13.*"]
enable_resolves = true

resolves = { python-default = "python-default.lock" }

02-BUILD

python_sources(
    name="lambda",
)

python_aws_lambda_function(
    handler="lambda_function.py:handler",
)

poetry_requirements(
    name="poetry",
)

03-pyproject.toml

[tool.poetry]
name = "whatever"
version = "0.1.0"
package-mode = false

[tool.poetry.dependencies]
python = "^3.13"
boto3 = "^1.40"

[tool.poetry.group.dev.dependencies]
pytest = "^8.4"
black = "^25.1"
ruff = "^0.12"

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

[tool.ruff]
line-length = 88
target-version = "py313"

[tool.black]
line-length = 88
target-version = ["py313"]

04-pants-peek-output.json

[
  {
    "address": "src/lambdas/whatever:whatever",
    "target_type": "python_aws_lambda_function",
    "architecture": "x86_64",
    "complete_platforms": null,
    "dependencies": [
      "src/lambdas/whatever/lambda_function.py:lambda"
    ],
    "dependencies_raw": null,
    "description": null,
    "environment": "__local__",
    "goals": [
      "package"
    ],
    "handler": "lambda_function.py:handler",
    "include_requirements": true,
    "layout": "flat-zipped",
    "output_path": "${spec_path_normalized}/${target_name_normalized}${file_suffix}",
    "pex3_venv_create_extra_args": [],
    "pex_build_extra_args": [],
    "resolve": null,
    "runtime": null,
    "tags": null
  },
  {
    "address": "src/lambdas/whatever:poetry#black",
    "target_type": "python_requirement",
    "_find_links": [],
    "dependencies": [
      "//python-default.lock:_python-default_lockfile",
      "src/lambdas/whatever/pyproject.toml:poetry"
    ],
    "dependencies_raw": [
      "src/lambdas/whatever/pyproject.toml:poetry",
      "python-default.lock:_python-default_lockfile"
    ],
    "description": null,
    "entry_point": null,
    "goals": [
      "run"
    ],
    "modules": null,
    "requirements": [
      "black<26.0.0,>=25.1"
    ],
    "resolve": null,
    "tags": null,
    "type_stub_modules": null
  },
  {
    "address": "src/lambdas/whatever:poetry#boto3",
    "target_type": "python_requirement",
    "_find_links": [],
    "dependencies": [
      "//python-default.lock:_python-default_lockfile",
      "src/lambdas/whatever/pyproject.toml:poetry"
    ],
    "dependencies_raw": [
      "src/lambdas/whatever/pyproject.toml:poetry",
      "python-default.lock:_python-default_lockfile"
    ],
    "description": null,
    "entry_point": null,
    "goals": [
      "run"
    ],
    "modules": null,
    "requirements": [
      "boto3<2.0.0,>=1.40"
    ],
    "resolve": null,
    "tags": null,
    "type_stub_modules": null
  },
  {
    "address": "src/lambdas/whatever:poetry#pytest",
    "target_type": "python_requirement",
    "_find_links": [],
    "dependencies": [
      "//python-default.lock:_python-default_lockfile",
      "src/lambdas/whatever/pyproject.toml:poetry"
    ],
    "dependencies_raw": [
      "src/lambdas/whatever/pyproject.toml:poetry",
      "python-default.lock:_python-default_lockfile"
    ],
    "description": null,
    "entry_point": null,
    "goals": [
      "run"
    ],
    "modules": null,
    "requirements": [
      "pytest<9.0.0,>=8.4"
    ],
    "resolve": null,
    "tags": null,
    "type_stub_modules": null
  },
  {
    "address": "src/lambdas/whatever:poetry#ruff",
    "target_type": "python_requirement",
    "_find_links": [],
    "dependencies": [
      "//python-default.lock:_python-default_lockfile",
      "src/lambdas/whatever/pyproject.toml:poetry"
    ],
    "dependencies_raw": [
      "src/lambdas/whatever/pyproject.toml:poetry",
      "python-default.lock:_python-default_lockfile"
    ],
    "description": null,
    "entry_point": null,
    "goals": [
      "run"
    ],
    "modules": null,
    "requirements": [
      "ruff<0.13.0,>=0.12"
    ],
    "resolve": null,
    "tags": null,
    "type_stub_modules": null
  },
  {
    "address": "src/lambdas/whatever/lambda_function.py:lambda",
    "target_type": "python_source",
    "dependencies": [
      "src/lambdas/whatever:poetry#boto3",
    ],
    "dependencies_raw": null,
    "description": null,
    "goals": [
      "run"
    ],
    "interpreter_constraints": null,
    "resolve": null,
    "restartable": false,
    "run_goal_use_sandbox": null,
    "skip_black": false,
    "skip_pyupgrade": false,
    "skip_ruff": false,
    "skip_ruff_check": false,
    "skip_ruff_format": false,
    "source_raw": "lambda_function.py",
    "sources": [
      "src/lambdas/whatever/lambda_function.py"
    ],
    "sources_fingerprint": "f3148d1eeb8bb1bc585c405ea0e67a02ab5d08c787679b85dfa53502674b971b",
    "tags": null
  },
  {
    "address": "src/lambdas/whatever/pyproject.toml:poetry",
    "target_type": "_generator_sources_helper",
    "dependencies": [],
    "description": null,
    "source_raw": "pyproject.toml",
    "sources": [
      "src/lambdas/whatever/pyproject.toml"
    ],
    "sources_fingerprint": "3916c407d1e5550a83967d6ea2fc60e9b38e72c9fe5110b085d99916f3fc364c",
    "tags": null
  }
]

05-desired-terraform.tf

# This is what I'd like to be able to do, pull the handler, runtime and architecture directly from the output of pants.

locals {
  lambda_base = "../dist/src.lambdas.whatever/whatever"
  lambda_config = jsondecode(file("${lambda_base}.json"))
}

resource "aws_lambda_function" "whatever_lambda" {
  function_name = "whatever_lambda"

  handler = local.lambda_config.handler
  runtime = local.lambda_config.runtime
  architectures = [local.lambda_config.architecture]

  filename         = "${lambda_base}.zip"
  source_code_hash = filebase64sha256("${lambda_base}.zip")
}