add gRPC health check

.chloggen/grpc-healthcheck.yaml

@@ -0,0 +1,25 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. otlpreceiver)
+component: configgrpc
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: gRPC servers now have the option to register the standard grpc.health.v1.Health healthcheck service.
+
+# One or more tracking issues or pull requests related to the change
+issues: [3040]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: [user]

config/configgrpc/README.md

@@ -110,4 +110,5 @@ see [confignet README](../confignet/README.md).
 - [`read_buffer_size`](https://godoc.org/google.golang.org/grpc#ReadBufferSize)
 - [`tls`](../configtls/README.md)
 - [`write_buffer_size`](https://godoc.org/google.golang.org/grpc#WriteBufferSize)
+- [`healthcheck`](https://github.com/grpc/grpc/blob/master/doc/health-checking.md): registers the health check service
 - [`auth`](../configauth/README.md)

config/configgrpc/configgrpc.go

@@ -21,6 +21,8 @@ import (
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/credentials/insecure"
 	"google.golang.org/grpc/encoding/gzip"
+	"google.golang.org/grpc/health"
+	"google.golang.org/grpc/health/grpc_health_v1"
 	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
@@ -143,6 +145,10 @@ type GRPCServerSettings struct {
 	// Keepalive anchor for all the settings related to keepalive.
 	Keepalive *KeepaliveServerConfig `mapstructure:"keepalive"`
 
+	// HealthCheck service for the gRPC server. See gRPC health checking.
+	// (https://github.com/grpc/grpc/blob/master/doc/health-checking.md)
+	HealthCheck bool `mapstructure:"healthcheck"`
+
 	// Auth for this receiver
 	Auth *configauth.Authentication `mapstructure:"auth"`
 
@@ -280,7 +286,12 @@ func (gss *GRPCServerSettings) ToServer(host component.Host, settings component.
 		return nil, err
 	}
 	opts = append(opts, extraOpts...)
-	return grpc.NewServer(opts...), nil
+	grpcServer := grpc.NewServer(opts...)
+	if gss.HealthCheck {
+		healthServer := health.NewServer()
+		grpc_health_v1.RegisterHealthServer(grpcServer, healthServer)
+	}
+	return grpcServer, nil
 }
 
 func (gss *GRPCServerSettings) toServerOption(host component.Host, settings component.TelemetrySettings) ([]grpc.ServerOption, error) {

config/configgrpc/configgrpc_test.go

@@ -19,6 +19,7 @@ import (
 	"go.uber.org/zap/zaptest/observer"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/balancer"
+	"google.golang.org/grpc/health/grpc_health_v1"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
 
@@ -236,6 +237,20 @@ func TestGrpcServerAuthSettings(t *testing.T) {
 	assert.NotNil(t, srv)
 }
 
+func TestGrpcHealthCheck(t *testing.T) {
+	gss := &GRPCServerSettings{
+		NetAddr: confignet.NetAddr{
+			Endpoint:  "localhost:1234",
+			Transport: "tcp",
+		},
+		HealthCheck: true,
+	}
+	gsvr, err := gss.ToServer(componenttest.NewNopHost(), componenttest.NewNopTelemetrySettings())
+	assert.NoError(t, err)
+	info := gsvr.GetServiceInfo()[grpc_health_v1.Health_ServiceDesc.ServiceName]
+	assert.Len(t, info.Methods, 2) // assert the 2 grpc health check endpoints were registered
+}
+
 func TestGRPCClientSettingsError(t *testing.T) {
 	tt, err := obsreporttest.SetupTelemetry(component.NewID("component"))
 	require.NoError(t, err)
@@ -424,7 +439,6 @@ func TestGRPCServerWarning(t *testing.T) {
 			require.Len(t, observed.FilterLevelExact(zap.WarnLevel).All(), test.len)
 		})
 	}
-
 }
 
 func TestGRPCServerSettingsError(t *testing.T) {