feat: add ping (#249)

* feat: adding ping

* add testing

* respect client timeout for pings

* correct error message

internal/grpcmanagers/data_manager.go

@@ -66,6 +66,7 @@ func NewLocalDataGrpcManager(request *models.LocalDataGrpcManagerRequest) (*Data
 	}
 	return &DataGrpcManager{Conn: conn}, nil
 }
+
 func (dataManager *DataGrpcManager) Close() momentoerrors.MomentoSvcErr {
 	return momentoerrors.ConvertSvcErr(dataManager.Conn.Close())
 }

internal/grpcmanagers/ping_manager.go

@@ -0,0 +1,40 @@
+package grpcmanagers
+
+import (
+	"crypto/tls"
+	"fmt"
+
+	"github.com/momentohq/client-sdk-go/internal/interceptor"
+	"github.com/momentohq/client-sdk-go/internal/models"
+	"github.com/momentohq/client-sdk-go/internal/momentoerrors"
+
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/credentials"
+)
+
+type PingGrpcManager struct {
+	Conn *grpc.ClientConn
+}
+
+const PingPort = ":443"
+
+func NewPingGrpcManager(request *models.PingGrpcManagerRequest) (*PingGrpcManager, momentoerrors.MomentoSvcErr) {
+	config := &tls.Config{
+		InsecureSkipVerify: false,
+	}
+	endpoint := fmt.Sprint(request.CredentialProvider.GetCacheEndpoint(), PingPort)
+	authToken := request.CredentialProvider.GetAuthToken()
+	conn, err := grpc.Dial(
+		endpoint,
+		grpc.WithTransportCredentials(credentials.NewTLS(config)),
+		grpc.WithUnaryInterceptor(interceptor.AddHeadersInterceptor(authToken)),
+	)
+	if err != nil {
+		return nil, momentoerrors.ConvertSvcErr(err)
+	}
+	return &PingGrpcManager{Conn: conn}, nil
+}
+
+func (pingManager *PingGrpcManager) Close() momentoerrors.MomentoSvcErr {
+	return momentoerrors.ConvertSvcErr(pingManager.Conn.Close())
+}

internal/models/requests.go

@@ -23,6 +23,10 @@ type DataStreamGrpcManagerRequest struct {
 	CredentialProvider auth.CredentialProvider
 }
 
+type PingGrpcManagerRequest struct {
+	CredentialProvider auth.CredentialProvider
+}
+
 type LocalDataGrpcManagerRequest struct {
 	Endpoint string
 }
@@ -54,3 +58,8 @@ type PubSubClientRequest struct {
 	Configuration      config.Configuration
 	CredentialProvider auth.CredentialProvider
 }
+
+type PingClientRequest struct {
+	Configuration      config.Configuration
+	CredentialProvider auth.CredentialProvider
+}

internal/services/scs_ping_service.go

@@ -0,0 +1,45 @@
+package services
+
+import (
+	"context"
+	"time"
+
+	"github.com/momentohq/client-sdk-go/internal/grpcmanagers"
+	"github.com/momentohq/client-sdk-go/internal/models"
+	"github.com/momentohq/client-sdk-go/internal/momentoerrors"
+	pb "github.com/momentohq/client-sdk-go/internal/protos"
+)
+
+type ScsPingClient struct {
+	requestTimeout time.Duration
+	grpcManager    *grpcmanagers.PingGrpcManager
+	grpcClient     pb.PingClient
+}
+
+func NewScsPingClient(request *models.PingClientRequest) (*ScsPingClient, momentoerrors.MomentoSvcErr) {
+	pingManager, err := grpcmanagers.NewPingGrpcManager(&models.PingGrpcManagerRequest{
+		CredentialProvider: request.CredentialProvider,
+	})
+	if err != nil {
+		return nil, err
+	}
+	return &ScsPingClient{
+		requestTimeout: request.Configuration.GetClientSideTimeout(),
+		grpcManager:    pingManager,
+		grpcClient:     pb.NewPingClient(pingManager.Conn),
+	}, nil
+}
+
+func (client *ScsPingClient) Close() momentoerrors.MomentoSvcErr {
+	return client.grpcManager.Close()
+}
+
+func (client *ScsPingClient) Ping(ctx context.Context) momentoerrors.MomentoSvcErr {
+	ctx, cancel := context.WithTimeout(ctx, client.requestTimeout)
+	defer cancel()
+	_, err := client.grpcClient.Ping(ctx, &pb.XPingRequest{})
+	if err != nil {
+		return momentoerrors.ConvertSvcErr(err)
+	}
+	return nil
+}

momento/cache_client.go

@@ -58,6 +58,8 @@ type CacheClient interface {
 	DictionaryRemoveField(ctx context.Context, r *DictionaryRemoveFieldRequest) (responses.DictionaryRemoveFieldResponse, error)
 	DictionaryRemoveFields(ctx context.Context, r *DictionaryRemoveFieldsRequest) (responses.DictionaryRemoveFieldsResponse, error)
 
+	Ping(ctx context.Context) (responses.PingResponse, error)
+
 	Close()
 }
 
@@ -66,6 +68,7 @@ type defaultScsClient struct {
 	credentialProvider auth.CredentialProvider
 	controlClient      *services.ScsControlClient
 	dataClient         *scsDataClient
+	pingClient         *services.ScsPingClient
 }
 
 type CacheClientProps struct {
@@ -82,7 +85,7 @@ func NewCacheClient(configuration config.Configuration, credentialProvider auth.
 		DefaultTtl:         defaultTtl,
 	}
 	if props.Configuration.GetClientSideTimeout() < 1 {
-		return nil, momentoerrors.NewMomentoSvcErr(momentoerrors.InvalidArgumentError, "request timeout must not be 0", nil)
+		return nil, momentoerrors.NewMomentoSvcErr(momentoerrors.InvalidArgumentError, "request timeout must be greater than 0", nil)
 	}
 	client := &defaultScsClient{
 		credentialProvider: props.CredentialProvider,
@@ -113,8 +116,17 @@ func NewCacheClient(configuration config.Configuration, credentialProvider auth.
 		return nil, convertMomentoSvcErrorToCustomerError(momentoerrors.ConvertSvcErr(err))
 	}
 
+	pingClient, err := services.NewScsPingClient(&models.PingClientRequest{
+		Configuration:      props.Configuration,
+		CredentialProvider: props.CredentialProvider,
+	})
+	if err != nil {
+		return nil, convertMomentoSvcErrorToCustomerError(momentoerrors.ConvertSvcErr(err))
+	}
+
 	client.dataClient = dataClient
 	client.controlClient = controlClient
+	client.pingClient = pingClient
 
 	return client, nil
 }
@@ -453,6 +465,13 @@ func (c defaultScsClient) DictionaryRemoveFields(ctx context.Context, r *Diction
 	return r.response, nil
 }
 
+func (c defaultScsClient) Ping(ctx context.Context) (responses.PingResponse, error) {
+	if err := c.pingClient.Ping(ctx); err != nil {
+		return nil, err
+	}
+	return &responses.PingSuccess{}, nil
+}
+
 func (c defaultScsClient) Close() {
 	defer c.controlClient.Close()
 	defer c.dataClient.Close()

momento/ping_test.go

@@ -0,0 +1,29 @@
+package momento_test
+
+import (
+	. "github.com/momentohq/client-sdk-go/momento/test_helpers"
+	. "github.com/momentohq/client-sdk-go/responses"
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("ping", func() {
+	var sharedContext SharedContext
+
+	BeforeEach(func() {
+		sharedContext = NewSharedContext()
+		sharedContext.CreateDefaultCache()
+		DeferCleanup(func() {
+			sharedContext.Close()
+		})
+	})
+
+	It("receives successful ping responses", func() {
+		for i := 0; i < 25; i++ {
+			Expect(
+				sharedContext.Client.Ping(sharedContext.Ctx),
+			).To(BeAssignableToTypeOf(&PingSuccess{}))
+		}
+	})
+
+})

responses/ping.go

@@ -0,0 +1,9 @@
+package responses
+
+type PingResponse interface {
+	isPingResponse()
+}
+
+type PingSuccess struct{}
+
+func (PingSuccess) isPingResponse() {}