Add OPAM to osv.dev

Author: Mehnert

osv/ecosystems/_ecosystems.py

@@ -24,6 +24,7 @@
 from .hex import Hex
 from .maven import Maven
 from .nuget import NuGet
+from .opam import Opam
 from .packagist import Packagist
 from .pub import Pub
 from .pypi import PyPI
@@ -55,6 +56,7 @@
     'MinimOS': APK,
     'npm': SemverEcosystem,
     'NuGet': NuGet,
+    'opam': Opam,
     'openEuler': RPM,
     'openSUSE': RPM,
     'Packagist': Packagist,

osv/ecosystems/opam.py

@@ -0,0 +1,49 @@
+"""OPAM ecosystem helper."""
+import requests
+import json
+
+from ..third_party.univers.debian import Version as DebianVersion
+from . import config
+
+class Opam(EnumerableEcosystem):
+    """OPAM packages ecosystem"""
+    def _sort_key(self, version):
+        # OPAM uses debian versioning
+        if not DebianVersion.is_valid(version):
+            # If debian version is not valid, it is most likely an invalid fixed
+            # version then sort it to the last/largest element
+            return DebianVersion(9999999999, '9999999999')
+        return DebianVersion.from_string(version)
+
+    _REPO = 'https://api.github.com/repos/ocaml/opam-repository/contents/packages/'
+    _REPO_ARCHIVE = 'https://api.github.com/repos/ocaml/opam-repository-archive/contents/packages/'
+
+    def enumerate_versions(self,
+                           package,
+                           introduced,
+                           fixed=None,
+                           last_affected=None,
+                           limits=None):
+        """Enumerate versions."""
+        response = requests.get(
+            self._REPO + package, timeout=config.timeout)
+        archive_response = requests.get(
+            self._REPO_ARCHIVE + package, timeout=config.timeout)
+        if response.status_code == 404 && archive_response.status_code == 404:
+            raise EnumerateError(f'Package {package} not found')
+        if response.status_code != 200 && archive_response.status_code != 200:
+            raise RuntimeError(
+                f'Failed to get OPAM versions for {package} with: {response.text}')
+
+        responses = {}
+
+        if response.status_code == 200:
+            responses.extend(response.json())
+        if archive_response.status_code == 200:
+            responses.extend(archive_response.json())
+
+        versions = [x["name"] for x in responses]
+
+        self.sort_versions(versions)
+        return self._get_affected_versions(versions, introduced, fixed,
+                                           last_affected, limits)

osv/purl_helpers.py

@@ -70,6 +70,8 @@
         EcosystemPURL('npm', None),
     'NuGet':
         EcosystemPURL('nuget', None),
+    'opam':
+        EcosystemPURL('opam', None),
     'openEuler':
         EcosystemPURL('rpm', 'openeuler'),
     'openSUSE':