add the opentelemetry tracing (#908)

* add the opentelemetry tracing

* fix the error sampler config

* 添加stream的链路跟踪

* fix the error field name

zrpc/internal/serverinterceptors/opentracinginterceptor_test.go

@@ -0,0 +1,36 @@
+package serverinterceptors
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/tal-tech/go-zero/core/opentelemetry"
+	"google.golang.org/grpc"
+)
+
+func TestUnaryOpenTracingInterceptor_Disable(t *testing.T) {
+	interceptor := UnaryOpenTracingInterceptor()
+	_, err := interceptor(context.Background(), nil, &grpc.UnaryServerInfo{
+		FullMethod: "/",
+	}, func(ctx context.Context, req interface{}) (interface{}, error) {
+		return nil, nil
+	})
+	assert.Nil(t, err)
+}
+
+func TestUnaryOpenTracingInterceptor_Enabled(t *testing.T) {
+	opentelemetry.StartAgent(opentelemetry.Config{
+		Name:     "go-zero-test",
+		Endpoint: "http://localhost:14268/api/traces",
+		Batcher:  "jaeger",
+		Sampler:  1.0,
+	})
+	interceptor := UnaryOpenTracingInterceptor()
+	_, err := interceptor(context.Background(), nil, &grpc.UnaryServerInfo{
+		FullMethod: "/package.TestService.GetUser",
+	}, func(ctx context.Context, req interface{}) (interface{}, error) {
+		return nil, nil
+	})
+	assert.Nil(t, err)
+}