Tests for and using example importer improver

Following are tests associated with example importer and improver to
make sure the importer improver framework is working properly.

Signed-off-by: Hritik Vijay <hritikxx8@gmail.com>

Author: Hritik14

vulnerabilities/tests/test_example.py

@@ -0,0 +1,118 @@
+import datetime
+import os
+from unittest.mock import patch
+
+from django.test import TestCase
+from packageurl import PackageURL
+from univers.version_constraint import VersionConstraint
+from univers.version_range import NginxVersionRange
+from univers.versions import SemverVersion
+
+from vulnerabilities import models
+from vulnerabilities.import_runner import ImportRunner
+from vulnerabilities.importer import AdvisoryData
+from vulnerabilities.importer import AffectedPackage
+from vulnerabilities.importer import Reference
+from vulnerabilities.importer import ScoringSystem
+from vulnerabilities.importer import VulnerabilitySeverity
+from vulnerabilities.importers.example import ExampleAliasImprover
+from vulnerabilities.importers.example import ExampleImporter
+from vulnerabilities.importers.example import parse_advisory_data
+from vulnerabilities.improve_runner import ImproveRunner
+from vulnerabilities.improvers.default import DefaultImprover
+
+
+def mock_fetch_advisory_data():
+    return [
+        {
+            "id": "CVE-2021-12341337",
+            "summary": "Dummy advisory",
+            "advisory_severity": "high",
+            "vulnerable": "0.6.18-1.20.0",
+            "fixed": "1.20.1",
+            "reference": "http://example.com/cve-2021-1234",
+            "published_on": "06-10-2021 UTC",
+        }
+    ]
+
+
+def mock_fetch_additional_aliases(alias):
+    alias_map = {
+        "CVE-2021-12341337": ["ANONSEC-1337", "CERTDES-1337"],
+    }
+    return alias_map.get(alias)
+
+
+@patch("vulnerabilities.importers.example.fetch_advisory_data", mock_fetch_advisory_data)
+@patch("vulnerabilities.importers.example.fetch_additional_aliases", mock_fetch_additional_aliases)
+class TestExampleImporter(TestCase):
+    def test_parse_advisory_data(self):
+        raw_data = mock_fetch_advisory_data()[0]
+        expected = AdvisoryData(
+            aliases=["CVE-2021-12341337"],
+            summary="Dummy advisory",
+            affected_packages=[
+                AffectedPackage(
+                    package=PackageURL(
+                        type="example",
+                        namespace=None,
+                        name="dummy_package",
+                        version=None,
+                        qualifiers={},
+                        subpath=None,
+                    ),
+                    affected_version_range=NginxVersionRange(
+                        constraints=(
+                            VersionConstraint(
+                                comparator=">=", version=SemverVersion(string="0.6.18")
+                            ),
+                            VersionConstraint(
+                                comparator="<=", version=SemverVersion(string="1.20.0")
+                            ),
+                        )
+                    ),
+                    fixed_version=SemverVersion(string="1.20.1"),
+                )
+            ],
+            references=[
+                Reference(
+                    reference_id="",
+                    url="http://example.com/cve-2021-1234",
+                    severities=[
+                        VulnerabilitySeverity(
+                            system=ScoringSystem(
+                                identifier="generic_textual",
+                                name="Generic textual severity rating",
+                                url="",
+                                notes="Severity for unknown scoring systems. Contains generic textual values like High, Low etc",
+                            ),
+                            value="high",
+                        )
+                    ],
+                )
+            ],
+            date_published=datetime.datetime(2021, 10, 6, 0, 0, tzinfo=datetime.timezone.utc),
+        )
+        actual = parse_advisory_data(raw_data)
+        assert actual == expected
+
+    def test_import_framework_using_example_importer(self):
+        raw_datas = mock_fetch_advisory_data()
+        ImportRunner(ExampleImporter).run()
+
+        for raw_data in raw_datas:
+            assert models.Advisory.objects.get(aliases__contains=raw_data["id"])
+
+    def test_improve_framework_using_example_improver(self):
+        ImportRunner(ExampleImporter).run()
+        ImproveRunner(DefaultImprover).run()
+        ImproveRunner(ExampleAliasImprover).run()
+        raw_datas = mock_fetch_advisory_data()
+
+        assert models.Package.objects.count() == 3
+        assert models.PackageRelatedVulnerability.objects.filter(fix=True).count() == 1
+        assert models.PackageRelatedVulnerability.objects.filter(fix=False).count() == 2
+        assert models.VulnerabilitySeverity.objects.count() == 1
+        assert models.VulnerabilityReference.objects.count() == 1
+        for raw_data in raw_datas:
+            assert models.Vulnerability.objects.get(summary=raw_data["summary"])