Projects: improve deletion

readthedocs/projects/models.py

@@ -691,6 +691,15 @@ def save(self, *args, **kwargs):
     def delete(self, *args, **kwargs):
         from readthedocs.projects.tasks.utils import clean_project_resources
 
+        # NOTE: We use _raw_delete to avoid Django fetching all objects
+        # before the deletion. Be careful when using _raw_delete, signals
+        # won't be sent, and can cause integrity problems if the model
+        # has relations with other models.
+        qs = self.page_views.all()
+        qs._raw_delete(qs.db)
+        qs = self.search_queries.all()
+        qs._raw_delete(qs.db)
+
         # Remove extra resources
         clean_project_resources(self)
 

readthedocs/projects/tasks/utils.py

@@ -87,6 +87,13 @@ def clean_project_resources(project, version=None, version_slug=None):
      sometimes to clean old resources.
 
     .. note::
+
+       This function shouldn't delete objects that can't be recreated
+       by re-activating the version (e.g. page views, search queries),
+       as it's used when a version is deactivated.
+
+    .. note::
+
        This function is usually called just before deleting project.
        Make sure to not depend on the project object inside the tasks.
     """
@@ -108,11 +115,16 @@ def clean_project_resources(project, version=None, version_slug=None):
         version_slug=version_slug,
     )
 
-    # Remove imported files
+    # NOTE: We use _raw_delete to avoid Django fetching all objects
+    # before the deletion. Be careful when using _raw_delete, signals
+    # won't be sent, and can cause integrity problems if the model
+    # has relations with other models.
     if version:
-        version.imported_files.all().delete()
+        qs = version.imported_files.all()
+        qs._raw_delete(qs.db)
     else:
-        project.imported_files.all().delete()
+        qs = project.imported_files.all()
+        qs._raw_delete(qs.db)
 
 
 @app.task()

readthedocs/projects/tests/test_models.py

@@ -3,7 +3,10 @@
 from django.test import TestCase
 from django_dynamic_fixture import get
 
-from readthedocs.projects.models import Feature, Project
+from readthedocs.analytics.models import PageView
+from readthedocs.builds.models import Build, Version
+from readthedocs.projects.models import Feature, ImportedFile, Project
+from readthedocs.search.models import SearchQuery
 
 
 class TestURLPatternsUtils(TestCase):
@@ -137,3 +140,15 @@ def test_proxied_api_prefix(self):
         self.assertEqual(self.project.proxied_api_url, "prefix/_/")
         self.assertEqual(self.project.proxied_api_host, "/prefix/_")
         self.assertEqual(self.project.proxied_api_prefix, "/prefix/")
+
+    def test_number_of_queries_on_project_deletion(self):
+        for i in range(5):
+            version = get(Version, project=self.project, slug=f"subproject-{i}", active=True, built=True)
+            for _ in range(50):
+                get(PageView, project=self.project, version=version)
+                get(ImportedFile, project=self.project, version=version)
+                get(SearchQuery, project=self.project, version=version)
+                get(Build, project=self.project, version=version)
+
+        with self.assertNumQueries(48):
+            self.project.delete()