feat(adapi): add heartbeat api

docs/design/autoware-interfaces/ad-api/features/heartbeat.md

@@ -0,0 +1,10 @@
+# Heartbeat
+
+## Related API
+
+- {{ link_ad_api('/api/system/heartbeat') }}
+
+## Description
+
+This API is used to check whether applications and Autoware are communicating properly.
+The message contains timestamp and sequence number to check for communication delays, order, and losses.

docs/design/autoware-interfaces/ad-api/index.md

@@ -26,6 +26,7 @@ Service providers can combine these use cases to define user stories and check i
 - [Get on and get off](./use-cases/get-on-off.md)
 - [Vehicle monitoring](./use-cases/vehicle-monitoring.md)
 - [Vehicle operation](./use-cases/vehicle-operation.md)
+- [System monitoring](./use-cases/system-monitoring.md)
 
 ## Features
 
@@ -40,3 +41,4 @@ Service providers can combine these use cases to define user stories and check i
 - [Vehicle status](./features/vehicle-status.md)
 - [Vehicle doors](./features/vehicle-doors.md)
 - [Cooperation](./features/cooperation.md)
+- [Heartbeat](./features/heartbeat.md)

docs/design/autoware-interfaces/ad-api/list/api/system/heartbeat.md

@@ -0,0 +1,17 @@
+---
+title: /api/system/heartbeat
+status: not released
+method: realtime stream
+type:
+  name: autoware_adapi_v1_msgs/msg/Heartbeat
+  msg:
+    - name: stamp
+      text: Timestamp in Autoware for delay checking.
+    - name: seq
+      text: Sequence number for order verification, wraps at 65535.
+---
+
+{% extends 'design/autoware-interfaces/templates/autoware-interface.jinja2' %}
+{% block description %}
+The heartbeat frequency is 10 Hz.
+{% endblock %}

docs/design/autoware-interfaces/ad-api/list/index.md

@@ -26,6 +26,7 @@
 | [/api/routing/set_route](./api/routing/set_route.md)                                             | v1.0.0       |
 | [/api/routing/set_route_points](./api/routing/set_route_points.md)                               | v1.0.0       |
 | [/api/routing/state](./api/routing/state.md)                                                     | v1.0.0       |
+| [/api/system/heartbeat](./api/system/heartbeat.md)                                               | not released |
 | [/api/vehicle/dimensions](./api/vehicle/dimensions.md)                                           | v1.1.0       |
 | [/api/vehicle/doors/command](./api/vehicle/doors/command.md)                                     | v1.2.0       |
 | [/api/vehicle/doors/layout](./api/vehicle/doors/layout.md)                                       | v1.2.0       |

docs/design/autoware-interfaces/ad-api/types/autoware_adapi_v1_msgs/msg/Heartbeat.md

@@ -0,0 +1,17 @@
+---
+# This file is generated by tools/autoware-interfaces/generate.py
+title: autoware_adapi_v1_msgs/msg/Heartbeat
+---
+
+{% extends 'design/autoware-interfaces/templates/autoware-data-type.jinja2' %}
+{% block definition %}
+
+```txt
+# Timestamp in Autoware for delay checking.
+builtin_interfaces/Time stamp
+
+# Sequence number for order verification, wraps at 65535.
+uint16 seq
+```
+
+{% endblock %}

docs/design/autoware-interfaces/ad-api/types/index.md

@@ -14,6 +14,7 @@
 - [autoware_adapi_v1_msgs/msg/DynamicObjectPath](./autoware_adapi_v1_msgs/msg/DynamicObjectPath.md)
 - [autoware_adapi_v1_msgs/msg/Gear](./autoware_adapi_v1_msgs/msg/Gear.md)
 - [autoware_adapi_v1_msgs/msg/HazardLights](./autoware_adapi_v1_msgs/msg/HazardLights.md)
+- [autoware_adapi_v1_msgs/msg/Heartbeat](./autoware_adapi_v1_msgs/msg/Heartbeat.md)
 - [autoware_adapi_v1_msgs/msg/LocalizationInitializationState](./autoware_adapi_v1_msgs/msg/LocalizationInitializationState.md)
 - [autoware_adapi_v1_msgs/msg/MotionState](./autoware_adapi_v1_msgs/msg/MotionState.md)
 - [autoware_adapi_v1_msgs/msg/MrmState](./autoware_adapi_v1_msgs/msg/MrmState.md)

docs/design/autoware-interfaces/ad-api/use-cases/system-monitoring.md

@@ -0,0 +1,5 @@
+# System monitoring
+
+## Heartbeat
+
+[Heartbeat](../features/heartbeat.md) is a reference for checking whether communication with Autoware is being performed properly.

yaml/autoware-interfaces.yaml

@@ -60,6 +60,10 @@ types:
   autoware_adapi_v1_msgs/msg/HazardLights:
     msg:
       status: uint8
+  autoware_adapi_v1_msgs/msg/Heartbeat:
+    msg:
+      seq: uint16
+      stamp: builtin_interfaces/msg/Time
   autoware_adapi_v1_msgs/msg/LocalizationInitializationState:
     msg:
       stamp: builtin_interfaces/msg/Time