feat(preprod): Add PR comments for snapshot base-build edge cases

src/sentry/preprod/vcs/pr_comments/snapshot_tasks.py

@@ -13,7 +13,12 @@
 from sentry.preprod.models import PreprodArtifact, PreprodComparisonApproval
 from sentry.preprod.snapshots.models import PreprodSnapshotComparison, PreprodSnapshotMetrics
 from sentry.preprod.snapshots.utils import build_changes_map
-from sentry.preprod.vcs.pr_comments.snapshot_templates import format_snapshot_pr_comment
+from sentry.preprod.vcs.pr_comments.snapshot_templates import (
+    format_missing_base_snapshot_pr_comment,
+    format_snapshot_pr_comment,
+    format_solo_snapshot_pr_comment,
+    format_waiting_for_base_snapshot_pr_comment,
+)
 from sentry.preprod.vcs.pr_comments.tasks import find_existing_comment_id, save_pr_comment_result
 from sentry.shared_integrations.exceptions import ApiError
 from sentry.silo.base import SiloMode
@@ -38,7 +43,10 @@
     retry=Retry(times=3, delay=60),
 )
 def create_preprod_snapshot_pr_comment_task(
-    preprod_artifact_id: int, caller: str | None = None, **kwargs: Any
+    preprod_artifact_id: int,
+    caller: str | None = None,
+    is_timeout_check: bool = False,
+    **kwargs: Any,
 ) -> None:
     try:
         artifact = PreprodArtifact.objects.select_related(
@@ -155,46 +163,75 @@ def create_preprod_snapshot_pr_comment_task(
 
         base_artifact_map = PreprodArtifact.get_base_artifacts_for_commit(all_artifacts)
 
-        post_on_added = artifact.project.get_option(POST_ON_ADDED_OPTION_KEY, default=False)
-        post_on_removed = artifact.project.get_option(POST_ON_REMOVED_OPTION_KEY, default=True)
-        post_on_changed = artifact.project.get_option(POST_ON_CHANGED_OPTION_KEY, default=True)
-        post_on_renamed = artifact.project.get_option(POST_ON_RENAMED_OPTION_KEY, default=False)
-        changes_map = build_changes_map(
-            all_artifacts,
-            snapshot_metrics_map,
-            comparisons_map,
-            fail_on_added=post_on_added,
-            fail_on_removed=post_on_removed,
-            fail_on_changed=post_on_changed,
-            fail_on_renamed=post_on_renamed,
-        )
+        is_solo = not base_artifact_map
 
-        has_changes = any(changes_map.values())
-        # Failed comparisons are absent from changes_map (which only tracks
-        # SUCCESS state), so check comparisons_map directly to avoid
-        # suppressing failure reports.
-        has_failures = any(
-            c.state == PreprodSnapshotComparison.State.FAILED for c in comparisons_map.values()
-        )
-        if not has_changes and not has_failures:
-            logger.info(
-                "preprod.snapshot_pr_comments.create.skipped_no_diff",
-                extra={"artifact_id": artifact.id},
+        existing_comment_id = find_existing_comment_id(all_for_pr, "snapshots")
+        cc_id = cc.id
+
+        if is_solo:
+            app_ids = {a.app_id for a in all_artifacts if a.app_id}
+            has_previous_snapshots = (
+                PreprodSnapshotMetrics.objects.filter(
+                    preprod_artifact__project_id=artifact.project_id,
+                    preprod_artifact__app_id__in=app_ids,
+                )
+                .exclude(preprod_artifact__commit_comparison_id=commit_comparison.id)
+                .exists()
+                if app_ids
+                else False
             )
-            return
+            is_first_upload = not has_previous_snapshots
 
-        comment_body = format_snapshot_pr_comment(
-            all_artifacts,
-            snapshot_metrics_map,
-            comparisons_map,
-            base_artifact_map,
-            changes_map,
-            approvals_map=approvals_map,
-            project=artifact.project,
-        )
+            if is_first_upload or not commit_comparison.base_sha:
+                comment_body = format_solo_snapshot_pr_comment(
+                    all_artifacts, snapshot_metrics_map, project=artifact.project
+                )
+            elif not is_timeout_check:
+                comment_body = format_waiting_for_base_snapshot_pr_comment(
+                    all_artifacts, snapshot_metrics_map, project=artifact.project
+                )
+            else:
+                comment_body = format_missing_base_snapshot_pr_comment(
+                    all_artifacts, snapshot_metrics_map, project=artifact.project
+                )
+        else:
+            post_on_added = artifact.project.get_option(POST_ON_ADDED_OPTION_KEY, default=False)
+            post_on_removed = artifact.project.get_option(POST_ON_REMOVED_OPTION_KEY, default=True)
+            post_on_changed = artifact.project.get_option(POST_ON_CHANGED_OPTION_KEY, default=True)
+            post_on_renamed = artifact.project.get_option(POST_ON_RENAMED_OPTION_KEY, default=False)
+            changes_map = build_changes_map(
+                all_artifacts,
+                snapshot_metrics_map,
+                comparisons_map,
+                fail_on_added=post_on_added,
+                fail_on_removed=post_on_removed,
+                fail_on_changed=post_on_changed,
+                fail_on_renamed=post_on_renamed,
+            )
 
-        existing_comment_id = find_existing_comment_id(all_for_pr, "snapshots")
-        cc_id = cc.id
+            has_changes = any(changes_map.values())
+            # Failed comparisons are absent from changes_map (which only tracks
+            # SUCCESS state), so check comparisons_map directly to avoid
+            # suppressing failure reports.
+            has_failures = any(
+                c.state == PreprodSnapshotComparison.State.FAILED for c in comparisons_map.values()
+            )
+            if not has_changes and not has_failures and not existing_comment_id:
+                logger.info(
+                    "preprod.snapshot_pr_comments.create.skipped_no_diff",
+                    extra={"artifact_id": artifact.id},
+                )
+                return
+
+            comment_body = format_snapshot_pr_comment(
+                all_artifacts,
+                snapshot_metrics_map,
+                comparisons_map,
+                base_artifact_map,
+                changes_map,
+                approvals_map=approvals_map,
+                project=artifact.project,
+            )
 
     post_snapshot_pr_comment_task.delay(
         organization_id=organization.id,

src/sentry/preprod/vcs/pr_comments/snapshot_templates.py

@@ -25,7 +25,6 @@ def format_snapshot_pr_comment(
     *,
     project: Project,
 ) -> str:
-    """Format a PR comment for snapshot comparisons."""
     if not artifacts:
         raise ValueError("Cannot format PR comment for empty artifact list")
 
@@ -90,12 +89,8 @@ def format_snapshot_pr_comment(
                 f" | {status} |"
             )
 
-    settings_url = project.organization.absolute_url(
-        f"/settings/projects/{project.slug}/mobile-builds/", query="tab=snapshots"
-    )
-
     table = f"{_HEADER}\n\n{COMPARISON_TABLE_HEADER}" + "\n".join(table_rows)
-    settings_link = f"[⚙️ {project.name} Snapshot Settings]({settings_url})"
+    settings_link = _format_settings_link(project)
 
     return f"{table}\n\n{settings_link}"
 
@@ -137,3 +132,76 @@ def _section_cell(count: int, section: str, artifact_url: str) -> str:
     if count > 0:
         return f"[{count}]({artifact_url}?selectedTypes={section})"
     return str(count)
+
+
+def _format_settings_link(project: Project) -> str:
+    settings_url = project.organization.absolute_url(
+        f"/settings/projects/{project.slug}/mobile-builds/", query="tab=snapshots"
+    )
+    return f"[⚙️ {project.name} Snapshot Settings]({settings_url})"
+
+
+def _format_solo_table(
+    artifacts: list[PreprodArtifact],
+    snapshot_metrics_map: dict[int, PreprodSnapshotMetrics],
+) -> str:
+    table_rows = []
+    for artifact in artifacts:
+        app_display, app_id = _app_display_info(artifact)
+        artifact_url = get_preprod_artifact_url(artifact, view_type="snapshots")
+        name_cell = _format_name_cell(app_display, app_id, artifact_url)
+        metrics = snapshot_metrics_map.get(artifact.id)
+        if metrics:
+            table_rows.append(
+                f"| {name_cell} | - | - | - | - | - | - | ✅ {metrics.image_count} uploaded |"
+            )
+        else:
+            table_rows.append(f"| {name_cell} | - | - | - | - | - | - | {PROCESSING_STATUS} |")
+    return f"{_HEADER}\n\n{COMPARISON_TABLE_HEADER}" + "\n".join(table_rows)
+
+
+_SOLO_MESSAGE = "Snapshot diffs will appear when we have a base upload to compare against. Make sure to upload snapshots from your main branch."
+_WAITING_MESSAGE = "Waiting for base snapshots to finish uploading. This comment will update automatically within ~10 minutes or fail."
+_MISSING_BASE_MESSAGE = "No base snapshots found to compare against. Make sure snapshots are uploaded from your main branch."
+
+
+def _format_solo_comment(
+    artifacts: list[PreprodArtifact],
+    snapshot_metrics_map: dict[int, PreprodSnapshotMetrics],
+    message: str,
+    *,
+    project: Project,
+) -> str:
+    if not artifacts:
+        raise ValueError("Cannot format PR comment for empty artifact list")
+    table = _format_solo_table(artifacts, snapshot_metrics_map)
+    return f"{table}\n\n{message}\n\n{_format_settings_link(project)}"
+
+
+def format_solo_snapshot_pr_comment(
+    artifacts: list[PreprodArtifact],
+    snapshot_metrics_map: dict[int, PreprodSnapshotMetrics],
+    *,
+    project: Project,
+) -> str:
+    return _format_solo_comment(artifacts, snapshot_metrics_map, _SOLO_MESSAGE, project=project)
+
+
+def format_waiting_for_base_snapshot_pr_comment(
+    artifacts: list[PreprodArtifact],
+    snapshot_metrics_map: dict[int, PreprodSnapshotMetrics],
+    *,
+    project: Project,
+) -> str:
+    return _format_solo_comment(artifacts, snapshot_metrics_map, _WAITING_MESSAGE, project=project)
+
+
+def format_missing_base_snapshot_pr_comment(
+    artifacts: list[PreprodArtifact],
+    snapshot_metrics_map: dict[int, PreprodSnapshotMetrics],
+    *,
+    project: Project,
+) -> str:
+    return _format_solo_comment(
+        artifacts, snapshot_metrics_map, _MISSING_BASE_MESSAGE, project=project
+    )

src/sentry/preprod/vcs/status_checks/snapshots/tasks.py

@@ -16,6 +16,7 @@
 from sentry.preprod.snapshots.models import PreprodSnapshotComparison, PreprodSnapshotMetrics
 from sentry.preprod.snapshots.utils import build_changes_map
 from sentry.preprod.url_utils import get_preprod_artifact_url
+from sentry.preprod.vcs.pr_comments.snapshot_tasks import create_preprod_snapshot_pr_comment_task
 from sentry.preprod.vcs.status_checks.snapshots.templates import (
     format_first_snapshot_status_check_messages,
     format_generated_snapshot_status_check_messages,
@@ -319,6 +320,14 @@ def create_preprod_snapshot_status_check_task(
             },
             countdown=MISSING_BASE_GRACE_PERIOD_SECONDS,
         )
+        create_preprod_snapshot_pr_comment_task.apply_async(
+            kwargs={
+                "preprod_artifact_id": preprod_artifact_id,
+                "caller": "missing_base_timeout",
+                "is_timeout_check": True,
+            },
+            countdown=MISSING_BASE_GRACE_PERIOD_SECONDS,
+        )
 
 
 def _compute_snapshot_status(