refactor: Backend dependencies and more

- Add backend dependencies: One backend can now depend on another
  backend.
- Re-factor 'DownloadArtifact':
  - Rename 'DownloadArtifact' to 'DownloadConfig'
  - Remove attributes 'name' and 'version' not relevant for downloads
  - Add helper properties:
      - 'filename' parses the URL to extract the file name from the end
      - 'headers' calls the function to generate a HTML header for the
         download
- Add OutputLogger helper class
- Re-factor handling of backend configurations in the target profiles.

Change-Id: Ifda6cf12c375d0c1747d7e4130a0370d22c3d33a
Signed-off-by: Benjamin Klimczak <benjamin.klimczak@arm.com>

3 files changed, 149 insertions, 48 deletions

diff --git a/tests/test_backend_install.py b/tests/test_backend_install.py
index 963766e..3636fb4 100644
--- a/tests/test_backend_install.py
+++ b/tests/test_backend_install.py
@@ -20,6 +20,7 @@ from mlia.backend.install import InstallFromPath
 from mlia.backend.install import PackagePathChecker
 from mlia.backend.install import StaticPathChecker
 from mlia.backend.repo import BackendRepository
+from mlia.utils.download import DownloadConfig
 
 
 @pytest.fixture(name="backend_repo")
@@ -104,11 +105,9 @@ def test_backend_installation_from_path(
 
 
 def test_backend_installation_download_and_install(
-    tmp_path: Path, backend_repo: MagicMock
+    tmp_path: Path, backend_repo: MagicMock, monkeypatch: pytest.MonkeyPatch
 ) -> None:
     """Test methods of backend installation."""
-    download_artifact_mock = MagicMock()
-
     tmp_archive = tmp_path.joinpath("sample.tgz")
     sample_file = tmp_path.joinpath("sample.txt")
     sample_file.touch()
@@ -116,13 +115,17 @@ def test_backend_installation_download_and_install(
     with tarfile.open(tmp_archive, "w:gz") as archive:
         archive.add(sample_file)
 
-    download_artifact_mock.download_to.return_value = tmp_archive
+    monkeypatch.setattr("mlia.backend.install.download", MagicMock())
+    monkeypatch.setattr(
+        "mlia.utils.download.DownloadConfig.filename",
+        tmp_archive,
+    )
 
     installation = BackendInstallation(
         "sample_backend",
         "Sample backend",
         "sample_backend",
-        download_artifact_mock,
+        DownloadConfig(url="NOT_USED", sha256_hash="NOT_USED"),
         None,
         lambda path: BackendInfo(path, copy_source=False),
         lambda eula_agreement, path: path,
diff --git a/tests/test_backend_manager.py b/tests/test_backend_manager.py
index 879353e..63c11ee 100644
--- a/tests/test_backend_manager.py
+++ b/tests/test_backend_manager.py
@@ -3,6 +3,7 @@
 """Tests for installation manager."""
 from __future__ import annotations
 
+from functools import partial
 from pathlib import Path
 from typing import Any
 from unittest.mock import call
@@ -23,6 +24,7 @@ from mlia.core.errors import InternalError
 def get_default_installation_manager_mock(
     name: str,
     already_installed: bool = False,
+    dependencies: list[str] | None = None,
 ) -> MagicMock:
     """Get mock instance for DefaultInstallationManager."""
     mock = MagicMock(spec=DefaultInstallationManager)
@@ -30,6 +32,7 @@ def get_default_installation_manager_mock(
     props = {
         "name": name,
         "already_installed": already_installed,
+        "dependencies": dependencies if dependencies else [],
     }
     for prop, value in props.items():
         setattr(type(mock), prop, PropertyMock(return_value=value))
@@ -49,6 +52,7 @@ def get_installation_mock(
     already_installed: bool = False,
     could_be_installed: bool = False,
     supported_install_type: type | tuple | None = None,
+    dependencies: list[str] | None = None,
 ) -> MagicMock:
     """Get mock instance for the installation."""
     mock = MagicMock(spec=Installation)
@@ -65,6 +69,7 @@ def get_installation_mock(
         "name": name,
         "already_installed": already_installed,
         "could_be_installed": could_be_installed,
+        "dependencies": dependencies if dependencies else [],
     }
     for prop, value in props.items():
         setattr(type(mock), prop, PropertyMock(return_value=value))
@@ -72,38 +77,45 @@ def get_installation_mock(
     return mock
 
 
-def _already_installed_mock() -> MagicMock:
-    return get_installation_mock(
-        name="already_installed",
-        already_installed=True,
-        supported_install_type=(DownloadAndInstall, InstallFromPath),
-    )
+_already_installed_mock = partial(
+    get_installation_mock,
+    name="already_installed",
+    already_installed=True,
+    supported_install_type=(DownloadAndInstall, InstallFromPath),
+)
 
 
-def _ready_for_installation_mock() -> MagicMock:
-    return get_installation_mock(
-        name="ready_for_installation",
-        already_installed=False,
-        could_be_installed=True,
-    )
+_ready_for_installation_mock = partial(
+    get_installation_mock,
+    name="ready_for_installation",
+    already_installed=False,
+    could_be_installed=True,
+)
 
 
-def _could_be_downloaded_and_installed_mock() -> MagicMock:
-    return get_installation_mock(
-        name="could_be_downloaded_and_installed",
-        already_installed=False,
-        could_be_installed=True,
-        supported_install_type=DownloadAndInstall,
-    )
+_could_be_downloaded_and_installed_mock = partial(
+    get_installation_mock,
+    name="could_be_downloaded_and_installed",
+    already_installed=False,
+    could_be_installed=True,
+    supported_install_type=DownloadAndInstall,
+)
 
 
-def _could_be_installed_from_mock() -> MagicMock:
-    return get_installation_mock(
-        name="could_be_installed_from",
-        already_installed=False,
-        could_be_installed=True,
-        supported_install_type=InstallFromPath,
-    )
+_could_be_installed_from_mock = partial(
+    get_installation_mock,
+    name="could_be_installed_from",
+    already_installed=False,
+    could_be_installed=True,
+    supported_install_type=InstallFromPath,
+)
+
+_already_installed_dep_mock = partial(
+    get_installation_mock,
+    name="already_installed_dep",
+    already_installed=True,
+    supported_install_type=(DownloadAndInstall, InstallFromPath),
+)
 
 
 def get_installation_manager(
@@ -114,13 +126,23 @@ def get_installation_manager(
 ) -> DefaultInstallationManager:
     """Get installation manager instance."""
     if not noninteractive:
-        monkeypatch.setattr(
-            "mlia.backend.manager.yes", MagicMock(return_value=yes_response)
+        return get_interactive_installation_manager(
+            installations, monkeypatch, MagicMock(return_value=yes_response)
         )
 
     return DefaultInstallationManager(installations, noninteractive=noninteractive)
 
 
+def get_interactive_installation_manager(
+    installations: list[Any],
+    monkeypatch: pytest.MonkeyPatch,
+    mock_interaction: MagicMock,
+) -> DefaultInstallationManager:
+    """Get and interactive installation manager instance using the given mock."""
+    monkeypatch.setattr("mlia.backend.manager.yes", mock_interaction)
+    return DefaultInstallationManager(installations, noninteractive=False)
+
+
 def test_installation_manager_filtering() -> None:
     """Test default installation manager."""
     already_installed = _already_installed_mock()
@@ -337,3 +359,74 @@ def test_show_env_details(monkeypatch: pytest.MonkeyPatch) -> None:
         monkeypatch,
     )
     manager.show_env_details()
+
+
+@pytest.mark.parametrize(
+    "dependency",
+    (
+        _ready_for_installation_mock(),
+        _already_installed_mock(),
+    ),
+)
+@pytest.mark.parametrize("yes_response", (True, False))
+def test_could_be_installed_with_dep(
+    dependency: MagicMock,
+    yes_response: bool,
+    tmp_path: Path,
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    """Test installation with a dependency."""
+    install_mock = _could_be_installed_from_mock(dependencies=[dependency.name])
+
+    yes_mock = MagicMock(return_value=yes_response)
+    manager = get_interactive_installation_manager(
+        [install_mock, dependency], monkeypatch, yes_mock
+    )
+    manager.install_from(tmp_path, install_mock.name)
+
+    if yes_response:
+        install_mock.install.assert_called_once()
+    else:
+        install_mock.install.assert_not_called()
+    install_mock.uninstall.assert_not_called()
+
+    dependency.install.assert_not_called()
+    dependency.uninstall.assert_not_called()
+
+
+def test_install_with_unknown_dep(
+    tmp_path: Path,
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    """Test installation with an unknown dependency."""
+    install_mock = _could_be_installed_from_mock(dependencies=["UNKNOWN_BACKEND"])
+
+    manager = get_installation_manager(False, [install_mock], monkeypatch)
+    with pytest.raises(ValueError):
+        manager.install_from(tmp_path, install_mock.name)
+
+    install_mock.install.assert_not_called()
+    install_mock.uninstall.assert_not_called()
+
+
+@pytest.mark.parametrize("yes_response", (True, False))
+def test_uninstall_with_dep(
+    yes_response: bool, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    """Test uninstalling a backend with a dependency."""
+    dependency = _already_installed_dep_mock()
+    install_mock = _already_installed_mock(dependencies=[dependency.name])
+    yes_mock = MagicMock(return_value=yes_response)
+    manager = get_interactive_installation_manager(
+        [install_mock, dependency], monkeypatch, yes_mock
+    )
+    manager.uninstall(install_mock.name)
+
+    install_mock.install.assert_not_called()
+    if yes_response:
+        install_mock.uninstall.assert_called_once()
+    else:
+        install_mock.uninstall.assert_not_called()
+
+    dependency.install.assert_not_called()
+    dependency.uninstall.assert_not_called()
diff --git a/tests/test_utils_download.py b/tests/test_utils_download.py
index 28af74f..7188c62 100644
--- a/tests/test_utils_download.py
+++ b/tests/test_utils_download.py
@@ -1,8 +1,9 @@
-# SPDX-FileCopyrightText: Copyright 2022, Arm Limited and/or its affiliates.
+# SPDX-FileCopyrightText: Copyright 2023, Arm Limited and/or its affiliates.
 # SPDX-License-Identifier: Apache-2.0
 """Tests for download functionality."""
 from __future__ import annotations
 
+import hashlib
 from contextlib import ExitStack as does_not_raise
 from pathlib import Path
 from typing import Any
@@ -14,7 +15,7 @@ import pytest
 import requests
 
 from mlia.utils.download import download
-from mlia.utils.download import DownloadArtifact
+from mlia.utils.download import DownloadConfig
 
 
 def response_mock(
@@ -69,9 +70,18 @@ def test_download(
         "mlia.utils.download.requests.get",
         MagicMock(return_value=response_mock(content_length, content_chunks)),
     )
+    hash_obj = hashlib.sha256()
+    for chunk in content_chunks:
+        hash_obj.update(chunk)
+    sha256_hash = hash_obj.hexdigest()
 
     dest = tmp_path / "sample.bin"
-    download("some_url", dest, show_progress=show_progress, label=label)
+    download(
+        dest,
+        DownloadConfig("some_url", sha256_hash=sha256_hash),
+        show_progress=show_progress,
+        label=label,
+    )
 
     assert dest.is_file()
     assert dest.read_bytes() == bytes(
@@ -92,7 +102,7 @@ def test_download(
             "10",
             [bytes(range(10))],
             "bad_hash",
-            pytest.raises(ValueError, match="Digests do not match"),
+            pytest.raises(ValueError, match="Hashes do not match."),
         ],
     ],
 )
@@ -111,15 +121,13 @@ def test_download_artifact_download_to(
     )
 
     with expected_error:
-        artifact = DownloadArtifact(
-            "test_artifact",
+        cfg = DownloadConfig(
             "some_url",
-            "artifact_filename",
-            "1.0",
             sha256_hash,
         )
 
-        dest = artifact.download_to(tmp_path)
+        dest = tmp_path / "artifact_filename"
+        download(dest, cfg)
         assert isinstance(dest, Path)
         assert dest.name == "artifact_filename"
 
@@ -133,16 +141,13 @@ def test_download_artifact_unable_to_overwrite(
         MagicMock(return_value=response_mock("10", [bytes(range(10))])),
     )
 
-    artifact = DownloadArtifact(
-        "test_artifact",
+    cfg = DownloadConfig(
         "some_url",
-        "artifact_filename",
-        "1.0",
         "sha256_hash",
     )
 
     existing_file = tmp_path / "artifact_filename"
     existing_file.touch()
 
-    with pytest.raises(ValueError, match=f"{existing_file} already exists"):
-        artifact.download_to(tmp_path)
+    with pytest.raises(FileExistsError, match=f"{existing_file} already exists."):
+        download(existing_file, cfg)