feat: add uv plugin to charmcraft (#2050)

Needs canonical/craft-parts#945

Closes #2040.
CRAFT-3816

---------

Co-authored-by: Alex Lowe <[email protected]>

.gitignore

@@ -92,6 +92,9 @@ ipython_config.py
 # Pycharm
 .idea
 
+# VS Code
+.vscode
+
 # pipenv
 #   According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control.
 #   However, in case of collaboration, if having platform-specific dependencies or dependencies

charmcraft/parts/__init__.py

@@ -41,6 +41,7 @@ def get_app_plugins() -> dict[str, type[craft_parts.plugins.Plugin]]:
         "poetry": plugins.PoetryPlugin,
         "python": plugins.PythonPlugin,
         "reactive": plugins.ReactivePlugin,
+        "uv": plugins.UvPlugin,
     }
 
 

charmcraft/parts/plugins/__init__.py

@@ -21,6 +21,8 @@
 from ._poetry import PoetryPlugin, PoetryPluginProperties
 from ._python import PythonPlugin, PythonPluginProperties
 from ._reactive import ReactivePlugin, ReactivePluginProperties
+from ._uv import UvPlugin
+from craft_parts.plugins.uv_plugin import UvPluginProperties
 
 __all__ = [
     "BundlePlugin",
@@ -33,4 +35,6 @@
     "PythonPluginProperties",
     "ReactivePlugin",
     "ReactivePluginProperties",
+    "UvPlugin",
+    "UvPluginProperties",
 ]

charmcraft/parts/plugins/_uv.py

@@ -0,0 +1,66 @@
+# Copyright 2024 Canonical Ltd.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# For further info, check https://github.com/canonical/charmcraft
+"""Charmcraft-specific uv plugin."""
+
+from pathlib import Path
+
+from craft_parts.plugins import uv_plugin
+from overrides import override
+
+from charmcraft import utils
+
+
+class UvPlugin(uv_plugin.UvPlugin):
+    @override
+    def get_build_environment(self) -> dict[str, str]:
+        return utils.extend_python_build_environment(super().get_build_environment())
+
+    @override
+    def _get_venv_directory(self) -> Path:
+        return self._part_info.part_install_dir / "venv"
+
+    @override
+    def _get_pip(self) -> str:
+        return 'uv pip --python="${PARTS_PYTHON_VENV_INTERP_PATH}"'
+
+    @override
+    def _get_package_install_commands(self) -> list[str]:
+        # Find the `uv sync` command and modify it to not install the project
+        orig_cmds = super()._get_package_install_commands()
+        for idx, cmd in enumerate(orig_cmds):
+            if cmd.startswith("uv sync"):
+                orig_cmds[idx] += " --no-install-project"
+                break
+
+        return [
+            *orig_cmds,
+            *utils.get_charm_copy_commands(
+                self._part_info.part_build_dir, self._part_info.part_install_dir
+            ),
+        ]
+
+    @override
+    def _should_remove_symlinks(self) -> bool:
+        return True
+
+    @override
+    def get_build_commands(self) -> list[str]:
+        return [
+            *super().get_build_commands(),
+            *utils.get_venv_cleanup_commands(
+                self._get_venv_directory(), keep_bins=False
+            ),
+        ]

docs/reference/plugins/index.rst

@@ -14,6 +14,7 @@ potentially the addition of further files using the :ref:`craft_parts_dump_plugi
     /common/craft-parts/reference/plugins/nil_plugin
     python_plugin
     poetry_plugin
+    uv_plugin
 
 .. warning::
    Other plugins are available from :external+craft-parts:ref:`craft-parts <plugins>`,

docs/reference/plugins/uv-charmcraft.yaml

@@ -0,0 +1,13 @@
+name: my-charm
+type: charm
+title: My uv charm
+summary: An operator charm using uv.
+description: |
+  An operator charm that uses uv for its project.
+base: [email protected]
+platforms:
+  amd64:
+parts:
+  my-charm:
+    source: .
+    plugin: uv

docs/reference/plugins/uv_plugin.rst

@@ -0,0 +1,49 @@
+.. _craft_parts_uv_plugin:
+
+uv plugin
+=========
+
+The uv plugin is designed for Python charms that use `uv`_ as the build system
+and are written with the `Operator framework`_.
+
+.. include:: /common/craft-parts/reference/plugins/uv_plugin.rst
+    :start-after: .. _craft_parts_uv_plugin-keywords:
+    :end-before: .. _craft_parts_uv_plugin-environment_variables:
+
+python-keep-bins
+~~~~~~~~~~~~~~~~
+**Type**: boolean
+**Default**: False
+
+Whether to keep Python scripts in the virtual environment's :file:`bin`
+directory.
+
+.. include:: /common/craft-parts/reference/plugins/uv_plugin.rst
+    :start-after: .. _craft_parts_poetry_plugin-environment_variables:
+    :end-before: .. _uv-details-end:
+
+How it works
+------------
+
+During the build step, the plugin performs the following actions:
+
+#. It creates a virtual environment in the
+   :ref:`${CRAFT_PART_INSTALL}/venv <craft_parts_step_execution_environment>`
+   directory.
+#. It runs :command:`uv sync` to install the packages referenced in the
+   :file:`pyproject.toml` and :file:`uv.lock` files, along with any optional
+   groups or extras specified.
+#. It copies any existing :file:`src` and :file:`lib` directories from your
+   charm project into the final charm.
+
+Example
+-------
+
+The following :file:`charmcraft.yaml` file can be used with a uv project to
+craft a charm with Ubuntu 24.04 as its base:
+
+.. literalinclude:: uv-charmcraft.yaml
+    :language: yaml
+
+
+.. _uv: https://docs.astral.sh/uv/

pyproject.toml

@@ -7,7 +7,7 @@ dependencies = [
     "craft-application~=4.7",
     "craft-cli>=2.3.0",
     "craft-grammar>=2.0.0",
-    "craft-parts>=2.2.0",
+    "craft-parts>=2.2.1",
     "craft-providers>=2.0.0",
     "craft-platforms~=0.5",
     "craft-providers>=2.0.0",

requirements-dev.txt

@@ -12,7 +12,7 @@ craft-application==4.7.0
 craft-archives==2.0.2
 craft-cli==2.13.0
 craft-grammar==2.0.1
-craft-parts==2.2.0
+craft-parts==2.2.1
 craft-platforms==0.5.0
 craft-providers==2.0.4
 craft-store==3.1.0

tests/conftest.py

@@ -460,3 +460,24 @@ def python_plugin(tmp_path: pathlib.Path):
     return craft_parts.plugins.get_plugin(
         part=part, part_info=part_info, properties=plugin_properties
     )
+
+
+@pytest.fixture
+def uv_plugin(tmp_path: pathlib.Path):
+    project_dirs = craft_parts.ProjectDirs(work_dir=tmp_path)
+    spec = {"plugin": "uv", "source": str(tmp_path)}
+    plugin_properties = parts.plugins.UvPluginProperties.unmarshal(spec)
+    part_spec = craft_parts.plugins.extract_part_properties(spec, plugin_name="uv")
+    part = craft_parts.Part(
+        "foo", part_spec, project_dirs=project_dirs, plugin_properties=plugin_properties
+    )
+    project_info = craft_parts.ProjectInfo(
+        application_name="test",
+        project_dirs=project_dirs,
+        cache_dir=tmp_path,
+    )
+    part_info = craft_parts.PartInfo(project_info, part=part)
+
+    return craft_parts.plugins.get_plugin(
+        part=part, part_info=part_info, properties=plugin_properties
+    )

tests/integration/parts/plugins/test_uv.py

@@ -0,0 +1,100 @@
+# Copyright 2024 Canonical Ltd.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# For further info, check https://github.com/canonical/charmcraft
+
+import platform
+import subprocess
+import sys
+from pathlib import Path
+from typing import Any
+
+import distro
+import pytest
+from craft_application import util as app_util
+
+from charmcraft import services
+from charmcraft.models import project
+
+pytestmark = [
+    pytest.mark.skipif(sys.platform != "linux", reason="craft-parts is linux-only")
+]
+
+
+@pytest.fixture
+def charm_project(basic_charm_dict: dict[str, Any], project_path: Path, request):
+    return project.PlatformCharm.unmarshal(
+        basic_charm_dict
+        | {
+            "base": f"{distro.id()}@{distro.version()}",
+            "platforms": {app_util.get_host_architecture(): None},
+            "parts": {
+                "my-charm": {
+                    "plugin": "uv",
+                    "source": str(project_path),
+                    "source-type": "local",
+                }
+            },
+        }
+    )
+
+
+@pytest.fixture
+def uv_project(project_path: Path, monkeypatch) -> None:
+    subprocess.run(
+        [
+            "uv",
+            "init",
+            "--name=test-charm",
+            f"--python={platform.python_version()}",
+            "--no-progress",
+            "--no-workspace",
+        ],
+        cwd=project_path,
+        check=True,
+    )
+    subprocess.run(["uv", "add", "ops"], cwd=project_path, check=True)
+    monkeypatch.delenv("UV_FROZEN", raising=False)
+    subprocess.run(
+        [
+            "uv",
+            "lock",
+        ],
+        cwd=project_path,
+        check=True,
+    )
+    source_dir = project_path / "src"
+    source_dir.mkdir()
+    (source_dir / "charm.py").write_text("# Charm file")
+
+
+@pytest.mark.slow
+@pytest.mark.usefixtures("uv_project")
+def test_uv_plugin(
+    build_plan, service_factory: services.CharmcraftServiceFactory, tmp_path: Path
+):
+    install_path = tmp_path / "parts" / "my-charm" / "install"
+    stage_path = tmp_path / "stage"
+    service_factory.lifecycle._build_plan = build_plan
+
+    service_factory.lifecycle.run("stage")
+
+    # Check that the part install directory looks correct.
+    assert (install_path / "src" / "charm.py").read_text() == "# Charm file"
+    assert (install_path / "venv" / "lib").is_dir()
+
+    # Check that the stage directory looks correct.
+    assert (stage_path / "src" / "charm.py").read_text() == "# Charm file"
+    assert (stage_path / "venv" / "lib").is_dir()
+    assert not (stage_path / "venv" / "lib64").is_symlink()

tests/spread/smoketests/uv/charmcraft.yaml

@@ -0,0 +1,16 @@
+type: charm
+name: test-charm
+summary: test-charm
+description: test-charm
+
+base: [email protected]
+platforms:
+  amd64:
+  arm64:
+  riscv64:
+
+parts:
+  my-part:
+    plugin: uv
+    source: .
+    build-snaps: [astral-uv]

tests/spread/smoketests/uv/hello.py

@@ -0,0 +1,6 @@
+def main():
+    print("Hello from uv!")
+
+
+if __name__ == "__main__":
+    main()

tests/spread/smoketests/uv/pyproject.toml

@@ -0,0 +1,6 @@
+[project]
+name = "testcharm"
+version = "0.1.0"
+description = "a revolutionary charm"
+requires-python = ">=3.10"
+dependencies = ["overrides", "ops"]

tests/spread/smoketests/uv/task.yaml

@@ -0,0 +1,9 @@
+summary: pack a charm with uv
+
+restore: |
+  rm -rf ./*.charm
+
+execute: |
+  charmcraft pack 2>&1
+  CHARM_OUTPUT=$(find . -type f -name "*.charm")
+  charmcraft analyse $CHARM_OUTPUT