Add poetry_requirements macro for Poetry support

src/python/pants/backend/python/macros/poetry_requirements.py

@@ -0,0 +1,283 @@
+# Copyright 2021 Pants project contributors (see CONTRIBUTORS.md).
+# Licensed under the Apache License, Version 2.0 (see LICENSE).
+
+from __future__ import annotations
+
+import itertools
+import logging
+import os
+from pathlib import Path
+from typing import Any, Iterable, Mapping, Optional
+
+import toml
+from packaging.version import InvalidVersion, Version
+from pkg_resources import Requirement
+
+from pants.base.build_environment import get_buildroot
+
+logger = logging.getLogger(__name__)
+
+
+def get_max_caret(proj_name: str, version: str, req: str, fp: str) -> str:
+    major = 0
+    minor = 0
+    micro = 0
+
+    try:
+        parsed_version = Version(version)
+    except InvalidVersion:
+        raise InvalidVersion(
+            f"Failed to parse requirement {req} in {fp} loaded by the poetry_requirements macro.\n\nIf you believe this requirement is valid, consider opening an issue at https://github.com/pantsbuild/pants/issues so that we can update Pants's Poetry macro to support this."
+        )
+
+    if parsed_version.major != 0:
+        major = parsed_version.major + 1
+    elif parsed_version.minor != 0:
+        minor = parsed_version.minor + 1
+    elif parsed_version.micro != 0:
+        micro = parsed_version.micro + 1
+    else:
+        base_len = len(parsed_version.base_version.split("."))
+        if base_len >= 3:
+            micro = 1
+        elif base_len == 2:
+            minor = 1
+        elif base_len == 1:
+            major = 1
+
+    return f"{major}.{minor}.{micro}"
+
+
+def get_max_tilde(proj_name: str, version: str, req: str, fp: str) -> str:
+    major = 0
+    minor = 0
+    try:
+        parsed_version = Version(version)
+    except InvalidVersion:
+        raise InvalidVersion(
+            f'Failed to parse requirement {proj_name} = "{req}" in {fp} loaded by the poetry_requirements macro.\n\nIf you believe this requirement is valid, consider opening an issue at https://github.com/pantsbuild/pants/issues so that we can update Pants\'s Poetry macro to support this.'
+        )
+    base_len = len(parsed_version.base_version.split("."))
+    if base_len >= 2:
+        minor = parsed_version.minor + 1
+        major = parsed_version.major
+    elif base_len == 1:
+        major = parsed_version.major + 1
+
+    return f"{major}.{minor}.0"
+
+
+def parse_str_version(proj_name: str, attributes: str, fp: str) -> str:
+    valid_specifiers = "<>!~="
+    pep440_reqs = []
+    comma_split_reqs = (i.strip() for i in attributes.split(","))
+    for req in comma_split_reqs:
+        if req[0] == "^":
+            max_ver = get_max_caret(proj_name, req[1:], req, fp)
+            min_ver = req[1:]
+            pep440_reqs.append(f">={min_ver},<{max_ver}")
+        # ~= is an acceptable default operator; however, ~ is not, and IS NOT the same as ~=
+        elif req[0] == "~" and req[1] != "=":
+            max_ver = get_max_tilde(proj_name, req[1:], req, fp)
+            min_ver = req[1:]
+            pep440_reqs.append(f">={min_ver},<{max_ver}")
+        else:
+            pep440_reqs.append(req if req[0] in valid_specifiers else f"=={req}")
+    return f"{proj_name} {','.join(pep440_reqs)}"
+
+
+def parse_python_constraint(constr: str | None, fp: str) -> str:
+    if constr is None:
+        return ""
+    valid_specifiers = "<>!~= "
+    or_and_split = [[j.strip() for j in i.split(",")] for i in constr.split("||")]
+    ver_parsed = [[parse_str_version("", j, fp) for j in i] for i in or_and_split]
+
+    def conv_and(lst: list[str]) -> list:
+        return list(itertools.chain(*[i.split(",") for i in lst]))
+
+    def prepend(version: str) -> str:
+        return (
+            f"python_version{''.join(i for i in version if i in valid_specifiers)} '"
+            f"{''.join(i for i in version if i not in valid_specifiers)}'"
+        )
+
+    prepend_and_clean = [
+        [prepend(".".join(j.split(".")[:2])) for j in conv_and(i)] for i in ver_parsed
+    ]
+    return (
+        f"{'(' if len(or_and_split) > 1 else ''}"
+        f"{') or ('.join([' and '.join(i) for i in prepend_and_clean])}"
+        f"{')' if len(or_and_split) > 1 else ''}"
+    )
+
+
+def handle_dict_attr(proj_name: str, attributes: dict[str, str], fp: str) -> str:
+    def produce_match(sep: str, feat: Optional[str]) -> str:
+        return f"{sep}{feat}" if feat else ""
+
+    git_lookup = attributes.get("git")
+    if git_lookup is not None:
+        rev_lookup = produce_match("#", attributes.get("rev"))
+        branch_lookup = produce_match("@", attributes.get("branch"))
+        tag_lookup = produce_match("@", attributes.get("tag"))
+
+        return f"{proj_name} @ git+{git_lookup}{tag_lookup}{branch_lookup}{rev_lookup}"
+
+    version_lookup = attributes.get("version")
+    path_lookup = attributes.get("path")
+    if path_lookup is not None:
+        return f"{proj_name} @ file://{path_lookup}"
+    url_lookup = attributes.get("url")
+    if url_lookup is not None:
+        return f"{proj_name} @ {url_lookup}"
+    if version_lookup is not None:
+        markers_lookup = produce_match(";", attributes.get("markers"))
+        python_lookup = parse_python_constraint(attributes.get("python"), fp)
+        version_parsed = parse_str_version(proj_name, version_lookup, fp)
+        return (
+            f"{version_parsed}"
+            f"{markers_lookup}"
+            f"{' and ' if python_lookup and markers_lookup else (';' if python_lookup else '')}"
+            f"{python_lookup}"
+        )
+    else:
+        raise AssertionError(
+            (
+                f"{proj_name} is not formatted correctly; at"
+                " minimum provide either a version, url, path or git location for"
+                " your dependency. "
+            )
+        )
+
+
+def parse_single_dependency(
+    proj_name: str, attributes: str | dict[str, Any] | list[dict[str, Any]], fp: str
+) -> tuple[Requirement, ...]:
+    if isinstance(attributes, str):
+        # E.g. `foo = "~1.1~'.
+        return (Requirement.parse(parse_str_version(proj_name, attributes, fp)),)
+    elif isinstance(attributes, dict):
+        # E.g. `foo = {version = "~1.1"}`.
+        return (Requirement.parse(handle_dict_attr(proj_name, attributes, fp)),)
+    elif isinstance(attributes, list):
+        # E.g. ` foo = [{version = "1.1","python" = "2.7"}, {version = "1.1","python" = "2.7"}]
+        return tuple(
+            Requirement.parse(handle_dict_attr(proj_name, attr, fp)) for attr in attributes
+        )
+    else:
+        raise AssertionError(
+            (
+                "Error: invalid poetry requirement format. Expected "
+                " type of requirement attributes to be string,"
+                f"dict, or list, but was of type {type(attributes).__name__}."
+            )
+        )
+
+
+def parse_pyproject_toml(toml_contents: str, file_path: str) -> set[Requirement]:
+    parsed = toml.loads(toml_contents)
+    try:
+        poetry_vals = parsed["tool"]["poetry"]
+    except KeyError:
+        raise KeyError(
+            (
+                f"No section `tool.poetry` found in {file_path}, which"
+                "is loaded by Pants from a `poetry_requirements` macro. "
+                "Did you mean to set up Poetry?"
+            )
+        )
+    dependencies = poetry_vals.get("dependencies", {})
+    dev_dependencies = poetry_vals.get("dev-dependencies", {})
+    if not dependencies and not dev_dependencies:
+        logger.warning(
+            (
+                "No requirements defined in poetry.tools.dependencies and"
+                f" poetry.tools.dev-dependencies in {file_path}, which is loaded by Pants"
+                " from a poetry_requirements macro. Did you mean to populate these"
+                " with requirements?"
+            )
+        )
+
+    return set(
+        itertools.chain.from_iterable(
+            parse_single_dependency(proj, attr, file_path)
+            for proj, attr in {**dependencies, **dev_dependencies}.items()
+        )
+    )
+
+
+class PoetryRequirements:
+    """Translates dependencies specified in a  pyproject.toml Poetry file to a set of
+    "python_requirements_library" targets.
+
+    For example, if pyproject.toml contains the following entries under
+    poetry.tool.dependencies: `foo = ">1"` and `bar = ">2.4"`,
+
+    python_requirement_library(
+        name="foo",
+        requirements=["foo>1"],
+      )
+
+      python_requirement_library(
+        name="bar",
+        requirements=["bar>2.4"],
+      )
+
+    See Poetry documentation for correct specification of pyproject.toml:
+    https://python-poetry.org/docs/pyproject/
+
+    You may also use the parameter `module_mapping` to teach Pants what modules each of your
+    requirements provide. For any requirement unspecified, Pants will default to the name of the
+    requirement. This setting is important for Pants to know how to convert your import
+    statements back into your dependencies. For example:
+
+        python_requirements(
+          module_mapping={
+            "ansicolors": ["colors"],
+            "setuptools": ["pkg_resources"],
+          }
+        )
+    """
+
+    def __init__(self, parse_context):
+        self._parse_context = parse_context
+
+    def __call__(
+        self,
+        pyproject_toml_relpath: str = "pyproject.toml",
+        *,
+        module_mapping: Optional[Mapping[str, Iterable[str]]] = None,
+    ) -> None:
+        """
+        :param pyproject_toml_relpath: The relpath from this BUILD file to the requirements file.
+            Defaults to a `requirements.txt` file sibling to the BUILD file.
+        :param module_mapping: a mapping of requirement names to a list of the modules they provide.
+            For example, `{"ansicolors": ["colors"]}`. Any unspecified requirements will use the
+            requirement name as the default module, e.g. "Django" will default to
+            `modules=["django"]`.
+        """
+        req_file_tgt = self._parse_context.create_object(
+            "_python_requirements_file",
+            name=pyproject_toml_relpath.replace(os.path.sep, "_"),
+            sources=[pyproject_toml_relpath],
+        )
+        requirements_dep = f":{req_file_tgt.name}"
+
+        req_file = Path(get_buildroot(), self._parse_context.rel_path, pyproject_toml_relpath)
+        requirements = parse_pyproject_toml(
+            req_file.read_text(), str(req_file.relative_to(get_buildroot()))
+        )
+        for parsed_req in requirements:
+            req_module_mapping = (
+                {parsed_req.project_name: module_mapping[parsed_req.project_name]}
+                if module_mapping and parsed_req.project_name in module_mapping
+                else None
+            )
+            self._parse_context.create_object(
+                "python_requirement_library",
+                name=parsed_req.project_name,
+                requirements=[parsed_req],
+                module_mapping=req_module_mapping,
+                dependencies=[requirements_dep],
+            )