De-duplicate builds

readthedocs/builds/migrations/0023_add_status_code.py

@@ -0,0 +1,18 @@
+# Generated by Django 2.2.12 on 2020-06-03 15:17
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('builds', '0022_migrate_protected_versions'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='build',
+            name='status_code',
+            field=models.BooleanField(blank=True, default=None, null=True, verbose_name='Status code'),
+        ),
+    ]

readthedocs/builds/models.py

@@ -615,6 +615,7 @@ class Build(models.Model):
         choices=BUILD_STATE,
         default='finished',
     )
+    status_code = models.BooleanField(_('Status code'), null=True, default=None, blank=True)
     date = models.DateTimeField(_('Date'), auto_now_add=True)
     success = models.BooleanField(_('Success'), default=True)
 

readthedocs/core/utils/__init__.py

@@ -19,7 +19,7 @@
 )
 from readthedocs.doc_builder.constants import DOCKER_LIMITS
 from readthedocs.projects.constants import CELERY_LOW, CELERY_MEDIUM, CELERY_HIGH
-from readthedocs.doc_builder.exceptions import BuildMaxConcurrencyError
+from readthedocs.doc_builder.exceptions import BuildMaxConcurrencyError, DuplicatedBuildError
 
 
 log = logging.getLogger(__name__)
@@ -165,8 +165,45 @@ def prepare_build(
         # External builds should be lower priority.
         options['priority'] = CELERY_LOW
 
+    skip_build = False
+    if commit:
+        skip_build = (
+            Build.objects
+            .filter(
+                project=project,
+                version=version,
+                commit=commit,
+            ).exclude(
+                state=BUILD_STATE_FINISHED,
+            ).exclude(
+                pk=build.pk,
+            ).exists()
+        )
+    else:
+        skip_build = Build.objects.filter(
+            project=project,
+            version=version,
+            state=BUILD_STATE_TRIGGERED,
+        ).count() > 1
+    if skip_build:
+        # TODO: we could mark the old build as duplicated, however we reset our
+        # position in the queue and go back to the end of it --penalization
+        log.warning(
+            'Marking build to be skipped by builder. project=%s version=%s build=%s commit=%s',
+            project.slug,
+            version.slug,
+            build.pk,
+            commit,
+        )
+        build.error = DuplicatedBuildError.message
+        build.status_code = DuplicatedBuildError.status_code
+        build.exit_code = DuplicatedBuildError.exit_code
+        build.success = False
+        build.state = BUILD_STATE_FINISHED
+        build.save()
+
     # Start the build in X minutes and mark it as limited
-    if project.has_feature(Feature.LIMIT_CONCURRENT_BUILDS):
+    if not skip_build and project.has_feature(Feature.LIMIT_CONCURRENT_BUILDS):
         running_builds = (
             Build.objects
             .filter(project__slug=project.slug)

readthedocs/doc_builder/exceptions.py

@@ -57,6 +57,12 @@ class BuildMaxConcurrencyError(BuildEnvironmentError):
     message = ugettext_noop('Concurrency limit reached ({limit}), retrying in 5 minutes.')
 
 
+class DuplicatedBuildError(BuildEnvironmentError):
+    message = ugettext_noop('Duplicated build.')
+    exit_code = 1
+    status_code = 0
+
+
 class BuildEnvironmentWarning(BuildEnvironmentException):
     pass
 

readthedocs/projects/tasks.py

@@ -58,6 +58,7 @@
     BuildEnvironmentWarning,
     BuildMaxConcurrencyError,
     BuildTimeoutError,
+    DuplicatedBuildError,
     MkDocsYAMLParseError,
     ProjectBuildsSkippedError,
     VersionLockedError,
@@ -542,6 +543,16 @@ def run(
             self.commit = commit
             self.config = None
 
+            if self.build['status_code'] == DuplicatedBuildError.status_code:
+                log.warning(
+                    'NOOP: build is marked as duplicated. project=%s version=%s build=%s commit=%s',
+                    self.project.slug,
+                    self.version.slug,
+                    build_pk,
+                    self.commit,
+                )
+                return True
+
             if self.project.has_feature(Feature.LIMIT_CONCURRENT_BUILDS):
                 response = api_v2.build.running.get(project__slug=self.project.slug)
                 builds_running = response.get('count', 0)

readthedocs/rtd_tests/tests/test_builds.py

@@ -18,8 +18,10 @@
     GENERIC_EXTERNAL_VERSION_NAME
 )
 from readthedocs.builds.models import Build, Version
+from readthedocs.core.utils import trigger_build
 from readthedocs.doc_builder.config import load_yaml_config
 from readthedocs.doc_builder.environments import LocalBuildEnvironment
+from readthedocs.doc_builder.exceptions import DuplicatedBuildError
 from readthedocs.doc_builder.python_environments import Virtualenv
 from readthedocs.oauth.models import RemoteRepository
 from readthedocs.projects.models import EnvironmentVariable, Project
@@ -747,3 +749,106 @@ def test_get_commit_url_internal_version(self):
             sha=build.commit
         )
         self.assertEqual(build.get_commit_url(), expected_url)
+
+
+
+@mock.patch('readthedocs.projects.tasks.update_docs_task')
+class DeDuplicateBuildTests(TestCase):
+
+    def setUp(self):
+        self.project = get(Project)
+        self.version = get(
+            Version,
+            project=self.project
+        )
+
+    def test_trigger_duplicated_build_by_commit(self, update_docs_task):
+        """
+        Trigger a build for the same commit twice.
+
+        The second build should be marked as NOOP.
+        """
+        self.assertEqual(Build.objects.count(), 0)
+        trigger_build(self.project, self.version, commit='a1b2c3')
+        self.assertEqual(Build.objects.count(), 1)
+        build = Build.objects.first()
+        self.assertEqual(build.state, 'triggered')
+
+        trigger_build(self.project, self.version, commit='a1b2c3')
+        self.assertEqual(Build.objects.count(), 2)
+        build = Build.objects.first()
+        self.assertEqual(build.error, DuplicatedBuildError.message)
+        self.assertEqual(build.success, False)
+        self.assertEqual(build.exit_code, DuplicatedBuildError.exit_code)
+        self.assertEqual(build.status_code, DuplicatedBuildError.status_code)
+        self.assertEqual(build.state, 'finished')
+
+    def test_trigger_duplicated_finshed_build_by_commit(self, update_docs_task):
+        """
+        Trigger a build for the same commit twice.
+
+        The second build should not be marked as NOOP if the previous
+        duplicated builds are in 'finished' state.
+        """
+        self.assertEqual(Build.objects.count(), 0)
+        trigger_build(self.project, self.version, commit='a1b2c3')
+        self.assertEqual(Build.objects.count(), 1)
+
+        # Mark the build as finished
+        build = Build.objects.first()
+        build.state = 'finished'
+        build.save()
+        build.refresh_from_db()
+
+        trigger_build(self.project, self.version, commit='a1b2c3')
+        self.assertEqual(Build.objects.count(), 2)
+        build = Build.objects.first()
+        self.assertEqual(build.state, 'triggered')
+        self.assertIsNone(build.status_code)
+
+    def test_trigger_duplicated_build_by_version(self, update_docs_task):
+        """
+        Trigger a build for the same version.
+
+        The second build should be marked as NOOP if there is already a build
+        for the same project and version on 'triggered' state.
+        """
+        self.assertEqual(Build.objects.count(), 0)
+        trigger_build(self.project, self.version, commit=None)
+        self.assertEqual(Build.objects.count(), 1)
+        build = Build.objects.first()
+        self.assertEqual(build.state, 'triggered')
+
+        trigger_build(self.project, self.version, commit=None)
+        self.assertEqual(Build.objects.count(), 2)
+        build = Build.objects.first()
+        self.assertEqual(build.error, DuplicatedBuildError.message)
+        self.assertEqual(build.success, False)
+        self.assertEqual(build.exit_code, DuplicatedBuildError.exit_code)
+        self.assertEqual(build.status_code, DuplicatedBuildError.status_code)
+        self.assertEqual(build.state, 'finished')
+
+    def test_trigger_duplicated_non_triggered_build_by_version(self, update_docs_task):
+        """
+        Trigger a build for the same version.
+
+        The second build should not be marked as NOOP because the previous build
+        for the same project and version is on 'building' state (any non 'triggered')
+        """
+        self.assertEqual(Build.objects.count(), 0)
+        trigger_build(self.project, self.version, commit=None)
+        self.assertEqual(Build.objects.count(), 1)
+        build = Build.objects.first()
+        self.assertEqual(build.state, 'triggered')
+
+        # Mark the build as building
+        build = Build.objects.first()
+        build.state = 'building'
+        build.save()
+        build.refresh_from_db()
+
+        trigger_build(self.project, self.version, commit=None)
+        self.assertEqual(Build.objects.count(), 2)
+        build = Build.objects.first()
+        self.assertEqual(build.state, 'triggered')
+        self.assertIsNone(build.status_code)