Reimplemented labels as HStore field

This solves the imminent performance issues.

fixes #3400

CHANGES/3400.bugfix

@@ -0,0 +1 @@
+Fixed label querying performance issues.

CHANGES/plugin_api/3400.removal

@@ -0,0 +1,2 @@
+Deprecated model ``Label`` and serializer field ``LabelField`` and ``LabelSelectFilter`` for
+removal in 3.25.

pulpcore/app/migrations/0097_pulp_labels.py

@@ -0,0 +1,92 @@
+# Generated by Django 3.2.16 on 2022-11-28 08:30
+
+import django.contrib.postgres.fields.hstore
+from django.db import migrations
+
+import os
+from django.contrib.postgres.operations import HStoreExtension
+from django.db.models.expressions import OuterRef, RawSQL
+from django.apps import apps as global_apps
+from pulpcore.app.apps import PulpPluginAppConfig
+
+
+def copy_labels_up(apps, schema_editor):
+    ContentType = apps.get_model("contenttypes", "ContentType")
+    Label = apps.get_model("core", "Label")
+
+    labeled_ctypes = [ContentType.objects.get(pk=pk) for pk in Label.objects.values_list("content_type", flat=True).distinct()]
+    labeled_models_ctypes = [(apps.get_model(ctype.app_label, ctype.model), ctype) for ctype in labeled_ctypes]
+    for model, ctype in labeled_models_ctypes:
+        label_subq = Label.objects.filter(content_type=ctype, object_id=OuterRef("pulp_id")).annotate(label_data=RawSQL("hstore(array_agg(key), array_agg(value))", [])).values("label_data")
+        model.objects.update(pulp_labels=label_subq)
+        Label.objects.filter(content_type=ctype).delete()
+
+    if Label.objects.count() != 0:
+        raise RuntimeError("Not all labels could be migrated properly. Please raise an issue and stand by for further investigation.")
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0096_alter_task_logging_cid'),
+        ('contenttypes', '0002_remove_content_type_name'),
+    ]
+    # Depend on all installed plugins containing migrations to be able to use their models.
+    for plugin_config in global_apps.app_configs.values():
+        if isinstance(plugin_config, PulpPluginAppConfig) and os.path.exists(plugin_config.path + "/migrations/0001_initial.py"):
+            dependencies.append((plugin_config.label, '0001_initial'))
+
+    operations = [
+        HStoreExtension(),
+        migrations.AddField(
+            model_name='alternatecontentsource',
+            name='pulp_labels',
+            field=django.contrib.postgres.fields.hstore.HStoreField(default=dict),
+        ),
+        migrations.AddField(
+            model_name='basedistribution',
+            name='pulp_labels',
+            field=django.contrib.postgres.fields.hstore.HStoreField(default=dict),
+        ),
+        migrations.AddField(
+            model_name='content',
+            name='pulp_labels',
+            field=django.contrib.postgres.fields.hstore.HStoreField(default=dict),
+        ),
+        migrations.AddField(
+            model_name='contentguard',
+            name='pulp_labels',
+            field=django.contrib.postgres.fields.hstore.HStoreField(default=dict),
+        ),
+        migrations.AddField(
+            model_name='distribution',
+            name='pulp_labels',
+            field=django.contrib.postgres.fields.hstore.HStoreField(default=dict),
+        ),
+        migrations.AddField(
+            model_name='exporter',
+            name='pulp_labels',
+            field=django.contrib.postgres.fields.hstore.HStoreField(default=dict),
+        ),
+        migrations.AddField(
+            model_name='importer',
+            name='pulp_labels',
+            field=django.contrib.postgres.fields.hstore.HStoreField(default=dict),
+        ),
+        migrations.AddField(
+            model_name='publication',
+            name='pulp_labels',
+            field=django.contrib.postgres.fields.hstore.HStoreField(default=dict),
+        ),
+        migrations.AddField(
+            model_name='remote',
+            name='pulp_labels',
+            field=django.contrib.postgres.fields.hstore.HStoreField(default=dict),
+        ),
+        migrations.AddField(
+            model_name='repository',
+            name='pulp_labels',
+            field=django.contrib.postgres.fields.hstore.HStoreField(default=dict),
+        ),
+        migrations.RunPython(code=copy_labels_up, reverse_code=migrations.RunPython.noop, elidable=True),
+    ]

pulpcore/app/models/__init__.py

@@ -4,6 +4,8 @@
 from .base import (  # noqa
     BaseModel,
     Label,
+    LabeledBaseModel,
+    LabeledMasterModel,
     MasterModel,
     pulp_uuid,
 )

pulpcore/app/models/base.py

@@ -3,11 +3,14 @@
 
 from django.contrib.contenttypes.fields import GenericRelation, GenericForeignKey
 from django.contrib.contenttypes.models import ContentType
+from django.contrib.postgres.fields import HStoreField
 from django.db import models
 from django.db.models import options
 from django.db.models.base import ModelBase
 from django_lifecycle import LifecycleModel
 
+from pulpcore.app.loggers import deprecation_logger
+
 
 def pulp_uuid():
     """
@@ -43,6 +46,13 @@ class Label(LifecycleModel):
 
     content_object = GenericForeignKey("content_type", "object_id", for_concrete_model=False)
 
+    def __init__(self, *args, **kwargs):
+        deprecation_logger.warning(
+            "'Label' is deprecated and will be removed in pulpcore==3.25;"
+            " use an 'HStoreField' named 'pulp_labels' instead."
+        )
+        super().__init__(*args, **kwargs)
+
     class Meta:
         unique_together = [["content_type", "object_id", "key"]]
 
@@ -59,7 +69,8 @@ class BaseModel(LifecycleModel):
         pulp_last_updated (models.DateTimeField): Last updated timestamp UTC.
 
     Relations:
-        pulp_labels (GenericRelation): A list of key/value labels.
+        user_roles (GenericRelation): List of user role associations with this object.
+        group_roles (GenericRelation): List of group role associations with this object.
 
     References:
 
@@ -71,7 +82,6 @@ class BaseModel(LifecycleModel):
     pulp_id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
     pulp_created = models.DateTimeField(auto_now_add=True)
     pulp_last_updated = models.DateTimeField(auto_now=True, null=True)
-    pulp_labels = GenericRelation(Label)
     user_roles = GenericRelation("core.UserRole")
     group_roles = GenericRelation("core.GroupRole")
 
@@ -90,6 +100,37 @@ def __repr__(self):
         return str(self)
 
 
+class LabeledBaseModel(BaseModel):
+    """
+    Base model class for all Pulp models using deprecated labels.
+
+    This class is DEPRECATED and scheduled for removal in 3.25.
+
+    This model inherits from `LifecycleModel` which allows all Pulp models to be used with
+    `django-lifecycle`.
+
+    Fields:
+        pulp_created (models.DateTimeField): Created timestamp UTC.
+        pulp_last_updated (models.DateTimeField): Last updated timestamp UTC.
+
+    Relations:
+        pulp_labels (GenericRelation): A list of key/value labels.
+        user_roles (GenericRelation): List of user role associations with this object.
+        group_roles (GenericRelation): List of group role associations with this object.
+
+    References:
+
+        * https://docs.djangoproject.com/en/3.2/topics/db/models/#automatic-primary-key-fields
+        * https://rsinger86.github.io/django-lifecycle/
+
+    """
+
+    pulp_labels = GenericRelation("core.Labels")
+
+    class Meta:
+        abstract = True
+
+
 class MasterModelMeta(ModelBase):
     def __new__(cls, name, bases, attrs, **kwargs):
         """Override __new__ to set the default_related_name."""
@@ -147,6 +188,7 @@ class MasterModel(BaseModel, metaclass=MasterModelMeta):
     # This field must have a value when models are saved, and defaults to the value of
     # the TYPE attribute on the Model being saved (seen above).
     pulp_type = models.TextField(null=False, default=None, db_index=True)
+    pulp_labels = HStoreField(default=dict)
 
     class Meta:
         abstract = True
@@ -247,3 +289,36 @@ def master_model(options):
 
 
 options.Options.master_model = property(master_model)
+
+
+class LabeledMasterModel(MasterModel):
+    """
+    Base model for the "Master" model in a "Master-Detail" relationship using deprecated labels.
+
+    This class is DEPRECATED and scheduled for removal in 3.25.
+
+    Provides methods for casting down to detail types, back up to the master type,
+    as well as a model field for tracking the type.
+
+    Attributes:
+
+        TYPE (str): Default constant value saved into the ``pulp_type``
+            field of Model instances
+
+    Fields:
+
+        pulp_type: The user-facing string identifying the detail type of this model
+
+    Warning:
+        Subclasses of this class rely on there being no other parent/child Model
+        relationships than the Master/Detail relationship. All subclasses must use
+        only abstract Model base classes for MasterModel to behave properly.
+        Specifically, OneToOneField relationships must not be used in any MasterModel
+        subclass.
+
+    """
+
+    pulp_labels = GenericRelation("core.Labels")
+
+    class Meta:
+        abstract = True

pulpcore/app/serializers/__init__.py

@@ -34,6 +34,7 @@
     RepositoryVersionIdentityField,
     relative_path_validator,
     TaskGroupStatusCountField,
+    pulp_labels_validator,
 )
 from .access_policy import AccessPolicySerializer  # noqa
 from .acs import (  # noqa

pulpcore/app/serializers/base.py

@@ -21,6 +21,7 @@
     get_viewset_for_model,
     get_request_without_query_params,
 )
+from pulpcore.app.serializers import LabelsField
 
 
 log = getLogger(__name__)
@@ -180,6 +181,8 @@ def create(self, validated_data):
         Returns:
             instance: The created of resource
         """
+        if not isinstance(self.fields.get("pulp_labels"), LabelsField):
+            return super().create(validated_data)
         labels = validated_data.pop("pulp_labels", {})
         with transaction.atomic():
             instance = super().create(validated_data)
@@ -196,6 +199,8 @@ def update(self, instance, validated_data):
         Returns:
             instance: The updated instance of resource
         """
+        if not isinstance(self.fields.get("pulp_labels"), LabelsField):
+            return super().update(validated_data)
         labels = validated_data.pop("pulp_labels", None)
         with transaction.atomic():
             instance = super().update(instance, validated_data)

pulpcore/app/serializers/fields.py

@@ -10,6 +10,7 @@
 
 from pulpcore.app import models
 from pulpcore.app.serializers import DetailIdentityField, IdentityField, RelatedField
+from pulpcore.app.loggers import deprecation_logger
 
 
 def relative_path_validator(relative_path):
@@ -381,6 +382,13 @@ def get_attribute(self, instance):
 class LabelsField(serializers.JSONField):
     """A serializer field for pulp_labels."""
 
+    def __init__(self, *args, **kwargs):
+        deprecation_logger.warning(
+            "'LabelsField' is deprecated and will be removed in pulpcore==3.25;"
+            " use an 'HStoreField' named 'pulp_labels' instead."
+        )
+        super().__init__(*args, **kwargs)
+
     def to_representation(self, labels):
         """
         Serializes list of labels to a dict.
@@ -421,3 +429,14 @@ def to_internal_value(self, data):
                 )
 
         return data
+
+
+def pulp_labels_validator(value):
+    """A validator designed for the pulp_labels field."""
+    for key, value in value.items():
+        if not re.match(r"^[\w ]+$", key):
+            raise serializers.ValidationError(_("Key '{}' contains non-alphanumerics.").format(key))
+        if re.search(r"[,()]", value):
+            raise serializers.ValidationError(
+                _("Key '{}' contains value with comma or parenthesis.").format(key)
+            )

pulpcore/app/serializers/publication.py

@@ -11,9 +11,9 @@
     DetailIdentityField,
     DetailRelatedField,
     GetOrCreateSerializerMixin,
-    LabelsField,
     ModelSerializer,
     RepositoryVersionRelatedField,
+    pulp_labels_validator,
     validate_unknown_fields,
 )
 from pulpcore.app.serializers.user import GroupUserSerializer, GroupSerializer
@@ -159,7 +159,7 @@ class DistributionSerializer(ModelSerializer):
     """
 
     pulp_href = DetailIdentityField(view_name_pattern=r"distributions(-.*/.*)-detail")
-    pulp_labels = LabelsField(required=False)
+    pulp_labels = serializers.HStoreField(required=False, validators=[pulp_labels_validator])
 
     base_path = serializers.CharField(
         help_text=_(

pulpcore/app/serializers/repository.py

@@ -10,20 +10,20 @@
 from pulpcore.app.serializers import (
     DetailIdentityField,
     DetailRelatedField,
-    LabelsField,
     LatestVersionField,
     ModelSerializer,
     RepositoryVersionIdentityField,
     RepositoryVersionRelatedField,
     RepositoryVersionsIdentityFromRepositoryField,
     ValidateFieldsMixin,
     HiddenFieldsMixin,
+    pulp_labels_validator,
 )
 
 
 class RepositorySerializer(ModelSerializer):
     pulp_href = DetailIdentityField(view_name_pattern=r"repositories(-.*/.*)-detail")
-    pulp_labels = LabelsField(required=False)
+    pulp_labels = serializers.HStoreField(required=False, validators=[pulp_labels_validator])
     versions_href = RepositoryVersionsIdentityFromRepositoryField()
     latest_version_href = LatestVersionField()
     name = serializers.CharField(
@@ -78,7 +78,7 @@ class RemoteSerializer(ModelSerializer, HiddenFieldsMixin):
     """
 
     pulp_href = DetailIdentityField(view_name_pattern=r"remotes(-.*/.*)-detail")
-    pulp_labels = LabelsField(required=False)
+    pulp_labels = serializers.HStoreField(required=False, validators=[pulp_labels_validator])
     name = serializers.CharField(
         help_text=_("A unique name for this remote."),
         validators=[UniqueValidator(queryset=models.Remote.objects.all())],

pulpcore/app/settings.py

@@ -70,6 +70,7 @@
     "django.contrib.sessions",
     "django.contrib.messages",
     "django.contrib.staticfiles",
+    "django.contrib.postgres",
     "import_export",
     # third-party
     "django_filters",