feat: add model for tracking codebase git mirror

* fix release ordering to sort by semantic version number rather than by
  string

django/library/jinja2/library/codebases/releases/retrieve.jinja

@@ -502,7 +502,7 @@
                 </tr>
                 </thead>
                 <tbody>
-                    {% for related_release in codebase.ordered_releases(has_change_perm) %}
+                    {% for related_release in codebase.ordered_releases(has_change_perm, asc=False) %}
                         <tr>
                             <td><a href='{{ related_release.get_absolute_url() }}'>{{ related_release.version_number }}</a></td>
                             <td>

django/library/migrations/0027_codebasegitmirror_codebase_git_mirror.py

@@ -0,0 +1,59 @@
+# Generated by Django 4.2.11 on 2024-05-07 22:25
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("library", "0026_alter_codebasereleaseplatformtag_tag_and_more"),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name="CodebaseGitMirror",
+            fields=[
+                (
+                    "id",
+                    models.AutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                ("repository_name", models.CharField(max_length=100, unique=True)),
+                (
+                    "remote_url",
+                    models.URLField(
+                        blank=True, help_text="URL of mirrored remote repository"
+                    ),
+                ),
+                ("last_local_update", models.DateTimeField(blank=True, null=True)),
+                ("last_remote_update", models.DateTimeField(blank=True, null=True)),
+                (
+                    "local_releases",
+                    models.ManyToManyField(
+                        related_name="+", to="library.codebaserelease"
+                    ),
+                ),
+                (
+                    "remote_releases",
+                    models.ManyToManyField(
+                        related_name="+", to="library.codebaserelease"
+                    ),
+                ),
+            ],
+        ),
+        migrations.AddField(
+            model_name="codebase",
+            name="git_mirror",
+            field=models.OneToOneField(
+                null=True,
+                on_delete=django.db.models.deletion.SET_NULL,
+                related_name="codebase",
+                to="library.codebasegitmirror",
+            ),
+        ),
+    ]

django/library/models.py

@@ -5,6 +5,7 @@
 import uuid
 from collections import OrderedDict
 from datetime import timedelta
+from packaging.version import Version
 
 import semver
 from django.conf import settings
@@ -535,6 +536,38 @@ def get_all_release_programming_languages(self, codebase):
         ).values_list("programming_languages__name", flat=True)
 
 
+class CodebaseGitMirror(models.Model):
+    """
+    model to keep track of the state of a git mirror for a codebase
+    """
+
+    repository_name = models.CharField(max_length=100, unique=True)
+    remote_url = models.URLField(
+        blank=True,
+        help_text=_("URL of mirrored remote repository"),
+    )
+    # keep track of timestamp and releases that have been mirrored locally
+    last_local_update = models.DateTimeField(null=True, blank=True)
+    local_releases = models.ManyToManyField("CodebaseRelease", related_name="+")
+    # keep track of timestamp and releases that have been synced to the remote
+    last_remote_update = models.DateTimeField(null=True, blank=True)
+    remote_releases = models.ManyToManyField("CodebaseRelease", related_name="+")
+
+    @property
+    def latest_local_release(self):
+        return max(self.local_releases.all(), key=lambda r: Version(r.version_number))
+
+    @property
+    def latest_remote_release(self):
+        return max(self.remote_releases.all(), key=lambda r: Version(r.version_number))
+
+    @property
+    def unmirrored_local_releases(self):
+        return self.codebase.ordered_releases().exclude(
+            id__in=self.local_releases.values_list("id", flat=True)
+        )
+
+
 @add_to_comses_permission_whitelist
 class Codebase(index.Indexed, ModeratedContent, ClusterableModel):
     """
@@ -570,6 +603,13 @@ class Codebase(index.Indexed, ModeratedContent, ClusterableModel):
         on_delete=models.SET_NULL,
     )
 
+    git_mirror = models.OneToOneField(
+        "CodebaseGitMirror",
+        null=True,
+        related_name="codebase",
+        on_delete=models.SET_NULL,
+    )
+
     repository_url = models.URLField(
         blank=True,
         help_text=_(
@@ -718,6 +758,16 @@ def base_library_dir(self):
     def base_git_dir(self):
         return pathlib.Path(settings.REPOSITORY_ROOT, str(self.uuid))
 
+    def create_git_mirror(self, repository_name, **kwargs):
+        if not self.git_mirror:
+            git_mirror = CodebaseGitMirror.objects.create(
+                repository_name=repository_name,
+                **kwargs,
+            )
+            self.git_mirror = git_mirror
+            self.save()
+        return self.git_mirror
+
     @property
     def codebase_contributors_redis_key(self):
         return f"codebase:contributors:{self.identifier}"
@@ -807,13 +857,19 @@ def download_count(self):
             release__codebase__id=self.id
         ).count()
 
-    def ordered_releases(self, has_change_perm=False, **kwargs):
-        releases = self.releases.order_by("-version_number").filter(**kwargs)
-        return (
-            releases
-            if has_change_perm
-            else releases.filter(status=CodebaseRelease.Status.PUBLISHED)
-        )
+    def ordered_releases(self, has_change_perm=False, asc=True, **kwargs):
+        """
+        list public releases (or all release if has_change_perm is True) in ascending (default) or descending order
+        """
+        if has_change_perm:
+            releases = self.releases.filter(**kwargs)
+        else:
+            releases = self.releases.filter(
+                status=CodebaseRelease.Status.PUBLISHED, **kwargs
+            )
+        releases_list = list(releases)
+        releases_list.sort(key=lambda r: Version(r.version_number), reverse=not asc)
+        return releases_list
 
     @classmethod
     def get_list_url(cls):