[Gateway] health check on gateway backend (#1728)

* feat: endpoint to fetch testnet health status

* create rpcClient and tenClient to call health

* feat: format health response

tools/walletextension/api/routes.go

@@ -63,6 +63,10 @@ func NewHTTPRoutes(walletExt *walletextension.WalletExtension) []Route {
 			Name: common.PathHealth,
 			Func: httpHandler(walletExt, healthRequestHandler),
 		},
+		{
+			Name: common.PathNetworkHealth,
+			Func: httpHandler(walletExt, networkHealthRequestHandler),
+		},
 		{
 			Name: common.PathVersion,
 			Func: httpHandler(walletExt, versionRequestHandler),
@@ -422,12 +426,40 @@ func healthRequestHandler(walletExt *walletextension.WalletExtension, conn userc
 		return
 	}
 
+	// TODO: connect to database and check if it is healthy
 	err = conn.WriteResponse([]byte(common.SuccessMsg))
 	if err != nil {
 		walletExt.Logger().Error("error writing success response", log.ErrKey, err)
 	}
 }
 
+// Handles request to /network-health endpoint.
+func networkHealthRequestHandler(walletExt *walletextension.WalletExtension, userConn userconn.UserConn) {
+	// read the request
+	_, err := userConn.ReadRequest()
+	if err != nil {
+		walletExt.Logger().Error("error reading request", log.ErrKey, err)
+		return
+	}
+
+	healthStatus, err := walletExt.GetTenNodeHealthStatus()
+
+	data, err := json.Marshal(map[string]interface{}{
+		"result": healthStatus,
+		"error":  err,
+	})
+	if err != nil {
+		walletExt.Logger().Error("error marshaling response", log.ErrKey, err)
+		return
+	}
+
+	err = userConn.WriteResponse(data)
+
+	if err != nil {
+		walletExt.Logger().Error("error writing success response", log.ErrKey, err)
+	}
+}
+
 // Handles request to /version endpoint.
 func versionRequestHandler(walletExt *walletextension.WalletExtension, userConn userconn.UserConn) {
 	// read the request

tools/walletextension/common/constants.go

@@ -35,6 +35,7 @@ const (
 	PathRevoke                          = "/revoke/"
 	PathObscuroGateway                  = "/"
 	PathHealth                          = "/health/"
+	PathNetworkHealth                   = "/network-health/"
 	WSProtocol                          = "ws://"
 	DefaultUser                         = "defaultUser"
 	UserQueryParameter                  = "u"

tools/walletextension/wallet_extension.go

@@ -11,6 +11,7 @@ import (
 	"github.com/ten-protocol/go-ten/tools/walletextension/config"
 
 	"github.com/ten-protocol/go-ten/go/common/log"
+	"github.com/ten-protocol/go-ten/go/obsclient"
 
 	"github.com/ten-protocol/go-ten/tools/walletextension/useraccountmanager"
 
@@ -38,6 +39,7 @@ type WalletExtension struct {
 	stopControl        *stopcontrol.StopControl
 	version            string
 	config             *config.Config
+	tenClient          *obsclient.ObsClient
 }
 
 func New(
@@ -49,6 +51,12 @@ func New(
 	logger gethlog.Logger,
 	config *config.Config,
 ) *WalletExtension {
+	rpcClient, err := rpc.NewNetworkClient(hostAddr)
+	if err != nil {
+		logger.Error(fmt.Errorf("could not create RPC client on %s. Cause: %w", hostAddr, err).Error())
+		panic(err)
+	}
+	newTenClient := obsclient.NewObsClient(rpcClient)
 	return &WalletExtension{
 		hostAddr:           hostAddr,
 		userAccountManager: userAccountManager,
@@ -58,6 +66,7 @@ func New(
 		stopControl:        stopControl,
 		version:            version,
 		config:             config,
+		tenClient:          newTenClient,
 	}
 }
 
@@ -384,3 +393,7 @@ func (w *WalletExtension) checkParametersForInterceptedGetStorageAt(params []int
 func (w *WalletExtension) Version() string {
 	return w.version
 }
+
+func (w *WalletExtension) GetTenNodeHealthStatus() (bool, error) {
+	return w.tenClient.Health()
+}