kuma-api: add proto definition for HealthCheck

api/mesh/v1alpha1/health_check.proto

@@ -0,0 +1,62 @@
+syntax = "proto3";
+
+package kuma.mesh.v1alpha1;
+
+option go_package = "v1alpha1";
+
+import "mesh/v1alpha1/selector.proto";
+
+import "google/protobuf/duration.proto";
+import "google/protobuf/wrappers.proto";
+
+import "validate/validate.proto";
+
+// HealthCheck defines configuration for health checking.
+message HealthCheck {
+
+  // List of selectors to match dataplanes that should be configured to do health checks.
+  repeated Selector sources = 1 [ (validate.rules).repeated .min_items = 1 ];
+
+  // List of selectors to match services that need to be health checked.
+  repeated Selector destinations = 2
+      [ (validate.rules).repeated .min_items = 1 ];
+
+  // Conf defines configuration for various types of health checking.
+  message Conf {
+
+    // Active defines configuration for active health checking.
+    message Active {
+
+      // Interval between consecutive health checks.
+      google.protobuf.Duration interval = 1 [(validate.rules).duration = {gt {}}];
+
+      // Maximum time to wait for a health check response.
+      google.protobuf.Duration timeout = 2 [(validate.rules).duration = {gt {}}];
+
+      // Number of consecutive unhealthy checks before considering a host unhealthy.
+      google.protobuf.UInt32Value unhealthy_threshold = 3 [(validate.rules).uint32 = {gt: 0}];
+
+      // Number of consecutive healthy checks before considering a host healthy.
+      google.protobuf.UInt32Value healthy_threshold = 4 [(validate.rules).uint32 = {gt: 0}];
+    }
+
+    // Passive defines configuration for passive health checking.
+    message Passive {
+
+      // Number of consecutive failed requests before considering a host unhealthy.
+      google.protobuf.UInt32Value unhealthy_threshold = 1 [(validate.rules).uint32 = {gt: 0}];
+
+      // Interval a host should be considred unhealthy after reaching unhealthy threshold.
+      google.protobuf.Duration penalty_interval = 2 [(validate.rules).duration = {gt {}}];
+    }
+
+    // Configuration for active health checking.
+    Active active_checks = 1;
+
+    // Configuration for passive health checking.
+    Passive passive_checks = 2;
+  }
+
+  // Configuration for various types of health checking.
+  Conf conf = 3;
+}