Added Outgoing Web hooks to escalation policy log (#4150)

# What this PR does

Adds the Outgoing web hooks escalation step to the escalation plan log.

## Which issue(s) this PR closes

Closes #4037

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## Checklist

- [x] Unit, integration, and e2e (if applicable) tests updated
- [x] Documentation added (or `pr:no public docs` PR label added if not
required)
- [x] Added the relevant release notes label (see labels prefixed w/
`release:`). These labels dictate how your PR will
    show up in the autogenerated release notes.

Co-authored-by: Joey Orlando <joey.orlando@grafana.com>

engine/apps/alerts/incident_log_builder/incident_log_builder.py

@@ -554,7 +554,15 @@ class IncidentLogBuilder:
                 # notification_plan_dict structure - {timedelta: [{"user_id": user.pk, "plan_lines": []}]
                 for timedelta, notification_plan in notification_plan_dict.items():
                     escalation_plan_dict.setdefault(timedelta, []).extend(notification_plan)
-        # TODO: should we add logic here for new webhooks?
+        elif escalation_policy_snapshot.step == EscalationPolicy.STEP_TRIGGER_CUSTOM_WEBHOOK:
+            if future_step:
+                custom_webhook = escalation_policy_snapshot.custom_webhook
+                if custom_webhook is not None:
+                    plan_line = f'trigger outgoing webhook "{custom_webhook.name}"'
+                else:
+                    plan_line = f'escalation step "{escalation_policy_snapshot.step_display}" but outgoing webhook is unspecified. Skipping'
+                plan = {"plan_lines": [plan_line]}
+                escalation_plan_dict.setdefault(timedelta, []).append(plan)
         elif escalation_policy_snapshot.step == EscalationPolicy.STEP_NOTIFY_IF_TIME:
             if future_step:
                 if escalation_policy_snapshot.from_time is not None and escalation_policy_snapshot.to_time is not None:

engine/apps/alerts/tests/test_incident_log_builder.py

@@ -37,3 +37,37 @@ def test_escalation_plan_messaging_backends(
     log_builder = IncidentLogBuilder(alert_group=alert_group)
     plan = log_builder.get_incident_escalation_plan()
     assert list(plan.values()) == [["send test only backend message to {}".format(user.username)]]
+
+
+@pytest.mark.django_db
+def test_escalation_plan_custom_webhooks(
+    make_organization_and_user,
+    make_escalation_chain,
+    make_escalation_policy,
+    make_custom_webhook,
+    make_alert_receive_channel,
+    make_channel_filter,
+    make_alert_group,
+):
+    organization, user = make_organization_and_user()
+    escalation_chain = make_escalation_chain(organization=organization)
+    custom_webhook = make_custom_webhook(organization=organization)
+    make_escalation_policy(
+        escalation_chain=escalation_chain,
+        escalation_policy_step=EscalationPolicy.STEP_WAIT,
+        wait_delay=EscalationPolicy.FIFTEEN_MINUTES,
+    )
+    make_escalation_policy(
+        escalation_chain=escalation_chain,
+        escalation_policy_step=EscalationPolicy.STEP_TRIGGER_CUSTOM_WEBHOOK,
+        custom_webhook=custom_webhook,
+    )
+    alert_receive_channel = make_alert_receive_channel(organization=organization)
+    channel_filter = make_channel_filter(alert_receive_channel, escalation_chain=escalation_chain)
+    alert_group = make_alert_group(alert_receive_channel, channel_filter=channel_filter)
+    alert_group.raw_escalation_snapshot = alert_group.build_raw_escalation_snapshot()
+    alert_group.save()
+
+    log_builder = IncidentLogBuilder(alert_group=alert_group)
+    plan = log_builder.get_incident_escalation_plan()
+    assert list(plan.values()) == [[f'trigger outgoing webhook "{custom_webhook.name}"']]