feat: Add metadata-writer ROCK (#68)

* Add ROCK used by kfp-metadata-writer charm.
* Add basic sanity tests for files in built image.
* Add tox.ini file.

Ref #66

.gitignore

@@ -2,3 +2,4 @@ venv
 charm_repo
 *.rock
 *.tar
+__pycache__

metadata-writer/rockcraft.yaml

@@ -0,0 +1,59 @@
+# Dockerfile: https://github.com/kubeflow/pipelines/blob/2.0.3/backend/metadata_writer/Dockerfile
+name: metadata-writer
+summary: Reusable end-to-end ML workflows built using the Kubeflow Pipelines SDK
+description: |
+  This service logs the metadata for KFP components and pipelines.
+version: 2.0.3
+license: Apache-2.0
+base: ubuntu@22.04
+run-user: _daemon_
+services:
+  controller:
+    override: replace
+    summary: "Entry point for kfp-metadata-writer oci-image"
+    command: python3 -u /kfp/metadata_writer/metadata_writer.py
+    startup: enabled
+platforms:
+  amd64:
+
+package-repositories:
+  - type: apt
+    ppa: deadsnakes/ppa
+    priority: always
+
+parts:
+  python:
+    plugin: python
+    source: https://github.com/kubeflow/pipelines.git
+    source-subdir: backend/metadata_writer
+    source-tag: 2.0.3
+    stage-packages:
+      # sync this python version to the base image in the Dockerfile.
+      # Also keep this in sync with PARTS_PYTHON_INTERPRETER below.
+    - python3.8-venv
+    python-requirements:
+    - requirements.txt
+    build-environment: 
+    - PARTS_PYTHON_INTERPRETER: python3.8
+
+  python3-is-python3.8:
+    plugin: nil
+    override-build: |
+      # Ensure `python3` is an executable command in our primed image by making
+      # a symbolic link
+      mkdir -p $CRAFT_PART_INSTALL/usr/bin/
+      ln -s /usr/bin/python3.8 $CRAFT_PART_INSTALL/usr/bin/python3
+
+  copy-files:
+    plugin: nil
+    source: https://github.com/kubeflow/pipelines.git
+    source-tag: 2.0.3
+    override-build: |
+      mkdir -p ${CRAFT_PART_INSTALL}/kfp/metadata_writer/
+      cp  ${CRAFT_PART_SRC}/backend/metadata_writer/src/* ${CRAFT_PART_INSTALL}/kfp/metadata_writer
+
+  security-team-requirement:
+    plugin: nil
+    override-build: |
+      mkdir -p ${CRAFT_PART_INSTALL}/usr/share/rocks
+      (echo "# os-release" && cat /etc/os-release && echo "# dpkg-query" && dpkg-query -f '${db:Status-Abbrev},${binary:Package},${Version},${source:Package},${Source:Version}\n' -W) > ${CRAFT_PART_INSTALL}/usr/share/rocks/dpkg.query

metadata-writer/tests/test_rock.py

@@ -0,0 +1,45 @@
+# Copyright 2024 Canonical Ltd.
+# See LICENSE file for licensing details.
+
+import pytest
+import subprocess
+
+from charmed_kubeflow_chisme.rock import CheckRock
+
+
+@pytest.mark.abort_on_fail
+def test_rock():
+    """Test rock."""
+    check_rock = CheckRock("rockcraft.yaml")
+    rock_image = check_rock.get_name()
+    rock_version = check_rock.get_version()
+    LOCAL_ROCK_IMAGE = f"{rock_image}:{rock_version}"
+
+    # assert the rock contains the expected files
+    subprocess.run(
+        [
+            "docker",
+            "run",
+            "--rm",
+            LOCAL_ROCK_IMAGE,
+            "exec",
+            "ls",
+            "-la",
+            "/kfp/metadata_writer/metadata_writer.py",
+        ],
+        check=True,
+    )
+
+    subprocess.run(
+        [
+            "docker",
+            "run",
+            "--rm",
+            LOCAL_ROCK_IMAGE,
+            "exec",
+            "ls",
+            "-la",
+            "/kfp/metadata_writer/metadata_helpers.py",
+        ],
+        check=True,
+    )

metadata-writer/tox.ini

@@ -0,0 +1,53 @@
+# Copyright 2022 Canonical Ltd.
+# See LICENSE file for licensing details.
+[tox]
+skipsdist = True
+skip_missing_interpreters = True
+envlist = unit, sanity, integration
+
+[testenv]
+setenv =
+    PYTHONPATH={toxinidir}
+    PYTHONBREAKPOINT=ipdb.set_trace
+    CHARM_REPO=https://github.com/canonical/kfp-operators.git
+    CHARM_BRANCH=main
+    LOCAL_CHARM_DIR=charm_repo
+
+[testenv:pack]
+passenv = *
+allowlist_externals =
+    rockcraft
+commands =
+    rockcraft pack
+
+[testenv:export-to-docker]
+passenv = *
+allowlist_externals =
+    bash
+    skopeo
+    yq
+commands =
+    # export to docker
+    bash -c 'NAME=$(yq eval .name rockcraft.yaml) && \
+             VERSION=$(yq eval .version rockcraft.yaml) && \
+             ARCH=$(yq eval ".platforms | keys | .[0]" rockcraft.yaml) && \
+             ROCK="$\{NAME\}_$\{VERSION\}_$\{ARCH\}.rock" && \
+             DOCKER_IMAGE=$NAME:$VERSION && \
+             echo "Exporting $ROCK to docker as $DOCKER_IMAGE" && \
+             skopeo --insecure-policy copy oci-archive:$ROCK docker-daemon:$DOCKER_IMAGE'
+
+[testenv:sanity]
+passenv = *
+deps =
+    pytest
+    charmed-kubeflow-chisme
+commands =
+    pytest -s -v --tb native --show-capture=all --log-cli-level=INFO {posargs} {toxinidir}/tests
+
+[testenv:integration]
+passenv = *
+allowlist_externals =
+    echo
+commands =
+    echo "WARNING: This is a placeholder test - no test is implemented here."
+