fix(aci): Rework logic to backfill open periods (#92532)

This PR changes the backfill logic to make sure it works with the
regressed/auto-resolved cycles that tripped us up earlier. There's also
a handful of cases where we see successive regressions / resolutions and
the old logic didn't know how to handle that. These changes will set the
open period based on the first regression/first resolution if there are
multiple in a row.

Makes for an easier review if you compare against the first commit which
just copies the changes from migration 0878

Author: snigdhas

migrations_lockfile.txt

@@ -23,7 +23,7 @@ preprod: 0001_emerge_upload_models
 
 replays: 0001_squashed_0005_drop_replay_index
 
-sentry: 0924_dashboard_add_unique_constraint_for_user_org_position
+sentry: 0925_backfill_open_periods
 
 social_auth: 0001_squashed_0002_default_auto_field
 

src/sentry/migrations/0925_backfill_open_periods.py

@@ -0,0 +1,206 @@
+# Generated by Django 5.2.1 on 2025-05-30 00:42
+
+import logging
+from collections import defaultdict
+from datetime import datetime
+from enum import Enum
+from typing import Any
+
+from django.conf import settings
+from django.db import IntegrityError, migrations, router, transaction
+from django.db.backends.base.schema import BaseDatabaseSchemaEditor
+from django.db.migrations.state import StateApps
+
+from sentry.new_migrations.migrations import CheckedMigration
+from sentry.utils import redis
+from sentry.utils.iterators import chunked
+from sentry.utils.query import RangeQuerySetWrapperWithProgressBarApprox
+
+logger = logging.getLogger(__name__)
+
+CHUNK_SIZE = 100
+
+
+# copied constants and enums
+class ActivityType(Enum):
+    SET_REGRESSION = 6
+    SET_RESOLVED = 1
+    SET_RESOLVED_IN_RELEASE = 13
+    SET_RESOLVED_BY_AGE = 15
+    SET_RESOLVED_IN_COMMIT = 16
+    SET_RESOLVED_IN_PULL_REQUEST = 21
+
+
+RESOLVED_ACTIVITY_TYPES = [
+    ActivityType.SET_RESOLVED.value,
+    ActivityType.SET_RESOLVED_IN_RELEASE.value,
+    ActivityType.SET_RESOLVED_BY_AGE.value,
+    ActivityType.SET_RESOLVED_IN_COMMIT.value,
+    ActivityType.SET_RESOLVED_IN_PULL_REQUEST.value,
+]
+
+
+class GroupStatus:
+    UNRESOLVED = 0
+    RESOLVED = 1
+
+
+# end copy
+
+
+def get_open_periods_for_group(
+    apps: StateApps,
+    group_id: int,
+    status: int,
+    project_id: int,
+    first_seen: datetime,
+    activities: list[Any],
+    GroupOpenPeriod: Any,
+) -> list[Any]:
+    # No activities means the group has been open since the first_seen date
+    if not activities:
+        return [
+            GroupOpenPeriod(
+                group_id=group_id,
+                project_id=project_id,
+                date_started=first_seen,
+            )
+        ]
+
+    open_periods = []
+    regression_time: datetime | None = first_seen
+    for activity in activities:
+        if activity.type == ActivityType.SET_REGRESSION.value and regression_time is None:
+            regression_time = activity.datetime
+
+        elif activity.type in RESOLVED_ACTIVITY_TYPES and regression_time is not None:
+            open_periods.append(
+                GroupOpenPeriod(
+                    group_id=group_id,
+                    project_id=project_id,
+                    date_started=regression_time,
+                    date_ended=activity.datetime,
+                    resolution_activity=activity,
+                    user_id=activity.user_id,
+                )
+            )
+
+            regression_time = None
+
+    # Handle currently open period if the group is unresolved
+    if status == GroupStatus.UNRESOLVED and regression_time is not None:
+        open_periods.append(
+            GroupOpenPeriod(
+                group_id=group_id,
+                project_id=project_id,
+                date_started=regression_time,
+            )
+        )
+
+    return open_periods
+
+
+def _backfill_group_open_periods(
+    apps: StateApps, group_data: list[tuple[int, datetime, int, int]]
+) -> None:
+    GroupOpenPeriod = apps.get_model("sentry", "GroupOpenPeriod")
+    Activity = apps.get_model("sentry", "Activity")
+
+    group_ids = [group_id for group_id, _, _, _ in group_data]
+    groups_with_open_periods = set(
+        GroupOpenPeriod.objects.filter(group_id__in=group_ids)
+        .values_list("group_id", flat=True)
+        .distinct()
+    )
+
+    group_ids = [group_id for group_id in group_ids if group_id not in groups_with_open_periods]
+    # Filter to REGRESSION and SET_RESOLVED_XX activties to find the bounds of each open period.
+    # The only UNRESOLVED activity we would care about is the first UNRESOLVED activity for the group creation,
+    # but we don't create an entry for that.
+
+    activities = defaultdict(list)
+    for activity in Activity.objects.filter(
+        group_id__in=group_ids,
+        type__in=[ActivityType.SET_REGRESSION.value, *RESOLVED_ACTIVITY_TYPES],
+    ).order_by("datetime"):
+        activities[activity.group_id].append(activity)
+
+    open_periods = []
+    for group_id, first_seen, status, project_id in group_data:
+        # Skip groups that already have open periods
+        if group_id in groups_with_open_periods:
+            continue
+
+        open_periods.extend(
+            get_open_periods_for_group(
+                apps,
+                group_id,
+                status,
+                project_id,
+                first_seen,
+                activities[group_id],
+                GroupOpenPeriod,
+            )
+        )
+
+    with transaction.atomic(router.db_for_write(GroupOpenPeriod)):
+        try:
+            GroupOpenPeriod.objects.bulk_create(open_periods)
+        except IntegrityError as e:
+            logger.exception(
+                "Error creating open period",
+                extra={"group_ids": group_ids, "error": e},
+            )
+
+
+def backfill_group_open_periods(apps: StateApps, schema_editor: BaseDatabaseSchemaEditor) -> None:
+    Group = apps.get_model("sentry", "Group")
+
+    backfill_key = "backfill_group_open_periods_from_activity_1"
+    redis_client = redis.redis_clusters.get(settings.SENTRY_MONITORS_REDIS_CLUSTER)
+
+    progress_id = int(redis_client.get(backfill_key) or 0)
+    for group_data in chunked(
+        RangeQuerySetWrapperWithProgressBarApprox(
+            Group.objects.filter(id__gt=progress_id).values_list(
+                "id", "first_seen", "status", "project_id"
+            ),
+            result_value_getter=lambda item: item[0],
+        ),
+        CHUNK_SIZE,
+    ):
+        logger.info(
+            "Processing batch for group open period backfill",
+            extra={"last_group_id": group_data[-1][0]},
+        )
+        _backfill_group_open_periods(apps, group_data)
+        # Save progress to redis in case we have to restart
+        redis_client.set(backfill_key, group_data[-1][0], ex=60 * 60 * 24 * 7)
+
+
+class Migration(CheckedMigration):
+    # This flag is used to mark that a migration shouldn't be automatically run in production.
+    # This should only be used for operations where it's safe to run the migration after your
+    # code has deployed. So this should not be used for most operations that alter the schema
+    # of a table.
+    # Here are some things that make sense to mark as post deployment:
+    # - Large data migrations. Typically we want these to be run manually so that they can be
+    #   monitored and not block the deploy for a long period of time while they run.
+    # - Adding indexes to large tables. Since this can take a long time, we'd generally prefer to
+    #   run this outside deployments so that we don't block them. Note that while adding an index
+    #   is a schema change, it's completely safe to run the operation after the code has deployed.
+    # Once deployed, run these manually via: https://develop.sentry.dev/database-migrations/#migration-deployment
+
+    is_post_deployment = True
+
+    dependencies = [
+        ("sentry", "0924_dashboard_add_unique_constraint_for_user_org_position"),
+    ]
+
+    operations = [
+        migrations.RunPython(
+            backfill_group_open_periods,
+            migrations.RunPython.noop,
+            hints={"tables": ["sentry_groupopenperiod"]},
+        ),
+    ]