implemented statedb status in /health endpoint (#967)

* implemented statedb status

* added new field to swagger.yml

* added comments for exported types and functions related to the statedb health checking

api/api.go

@@ -35,6 +35,7 @@ import (
 	"github.com/hermeznetwork/hermez-node/api/parsers"
 	"github.com/hermeznetwork/hermez-node/db/historydb"
 	"github.com/hermeznetwork/hermez-node/db/l2db"
+	"github.com/hermeznetwork/hermez-node/db/statedb"
 	"github.com/hermeznetwork/hermez-node/metric"
 	"github.com/hermeznetwork/tracerr"
 	"gopkg.in/go-playground/validator.v9"
@@ -45,6 +46,7 @@ type API struct {
 	h             *historydb.HistoryDB
 	cg            *configAPI
 	l2            *l2db.L2DB
+	stateDB       *statedb.StateDB
 	hermezAddress ethCommon.Address
 	validate      *validator.Validate
 }
@@ -56,6 +58,7 @@ func NewAPI(
 	server *gin.Engine,
 	hdb *historydb.HistoryDB,
 	l2db *l2db.L2DB,
+	stateDB *statedb.StateDB,
 	ethClient *ethclient.Client,
 	forgerAddress *ethCommon.Address,
 ) (*API, error) {
@@ -80,6 +83,7 @@ func NewAPI(
 			ChainID:           consts.ChainID,
 		},
 		l2:            l2db,
+		stateDB:       stateDB,
 		hermezAddress: consts.HermezAddress,
 		validate:      newValidate(),
 	}

api/api_test.go

@@ -259,6 +259,7 @@ func TestMain(m *testing.M) {
 		l2DB,
 		nil,
 		nil,
+		nil,
 	)
 	if err != nil {
 		log.Error(err)
@@ -668,6 +669,7 @@ func TestTimeout(t *testing.T) {
 		l2DBTO,
 		nil,
 		nil,
+		nil,
 	)
 	require.NoError(t, err)
 

api/health.go

@@ -24,6 +24,10 @@ func (a *API) healthRoute(version string, ethClient *ethclient.Client, forgerAdd
 		historyDBChecker := checkers.NewCheckerWithDB(a.h.DB().DB)
 		healthHandler.AddChecker("historyDB", historyDBChecker)
 	}
+	if a.stateDB != nil {
+		stateDBChecker := checkers.NewStateDBChecker(a.stateDB)
+		healthHandler.AddChecker("stateDB", stateDBChecker)
+	}
 	healthHandler.AddInfo("version", version)
 	t := time.Now().UTC()
 	healthHandler.AddInfo("timestamp", t)

api/swagger.yml

@@ -3410,6 +3410,22 @@ components:
             - status
             - version
           additionalProperties: false
+        statedb:
+          type: object
+          description: state db connection status
+          properties:
+            status:
+              type: string
+              description: Status of the connection. Possible responses - UP or DOWN
+              example: UP
+            batchNum:
+              type: integer
+              description: current batch num in last checkpoint of the state db
+              example: 24025
+            root:
+              type: integer
+              description: root of the underlying Merkle Tree in the last checkpoint of the state db
+              example: 20723800499378797360494097450413598946834655273323161758167114779532027183222
         status:
           type: string
           description: Status of the hermez node. Possible responses - UP or DOWN
@@ -3424,7 +3440,7 @@ components:
           example: v1.2.0
         coordinatorForgerBalance:
           type: string
-          description: Coordinator balance in ether. Returned with 18 decimals.
+          description: Coordinator balance in ether. Returned with 18 decimals. Not returned if node not in coord mode
           example: 48901270356066543960
       required:
         - historyDB

db/kvdb/kvdb.go

@@ -134,7 +134,6 @@ func NewKVDB(cfg Config) (*KVDB, error) {
 	if err != nil {
 		return nil, tracerr.Wrap(err)
 	}
-
 	var last *Last
 	if !cfg.NoLast {
 		last = &Last{
@@ -435,7 +434,6 @@ func (k *KVDB) MakeCheckpoint() error {
 			return tracerr.Wrap(err)
 		}
 	}
-
 	// execute Checkpoint
 	if err := k.db.Pebble().Checkpoint(checkpointPath); err != nil {
 		return tracerr.Wrap(err)

db/statedb/statedb.go

@@ -149,7 +149,6 @@ func NewStateDB(cfg Config) (*StateDB, error) {
 		return nil, tracerr.Wrap(
 			fmt.Errorf("invalid StateDB parameters: StateDB type==TypeStateDB can not have nLevels!=0"))
 	}
-
 	return &StateDB{
 		cfg: cfg,
 		db:  kv,

health/checkers/statedb.go

@@ -0,0 +1,41 @@
+package checkers
+
+import (
+	"github.com/dimiro1/health"
+	"github.com/hermeznetwork/hermez-node/db/statedb"
+)
+
+// StateDBChecker struct for state db connection checker
+type StateDBChecker struct {
+	stateDB *statedb.StateDB
+}
+
+// NewStateDBChecker init state db connection checker
+func NewStateDBChecker(sdb *statedb.StateDB) StateDBChecker {
+	return StateDBChecker{
+		stateDB: sdb,
+	}
+}
+
+// Check state db health
+func (sdb StateDBChecker) Check() health.Health {
+	h := health.NewHealth()
+
+	batchNum, err := sdb.stateDB.LastGetCurrentBatch()
+	if err != nil {
+		h.Down().AddInfo("error", err.Error())
+		return h
+	}
+
+	root, err := sdb.stateDB.LastMTGetRoot()
+	if err != nil {
+		h.Down().AddInfo("error", err.Error())
+		return h
+	}
+
+	h.Up().
+		AddInfo("batchNum", batchNum).
+		AddInfo("root", root)
+
+	return h
+}

node/node.go

@@ -459,6 +459,7 @@ func NewNode(mode Mode, cfg *config.Node, version string) (*Node, error) {
 			server,
 			historyDB,
 			l2DB,
+			stateDB,
 			ethClient,
 			&cfg.Coordinator.ForgerAddress,
 		)
@@ -573,6 +574,7 @@ func NewAPIServer(mode Mode, cfg *config.APIServer, version string, ethClient *e
 		server,
 		historyDB,
 		l2DB,
+		nil,
 		ethClient,
 		forgerAddress,
 	)
@@ -629,6 +631,7 @@ func NewNodeAPI(
 	server *gin.Engine,
 	hdb *historydb.HistoryDB,
 	l2db *l2db.L2DB,
+	stateDB *statedb.StateDB,
 	ethClient *ethclient.Client,
 	forgerAddress *ethCommon.Address,
 ) (*NodeAPI, error) {
@@ -640,6 +643,7 @@ func NewNodeAPI(
 		engine,
 		hdb,
 		l2db,
+		stateDB,
 		ethClient,
 		forgerAddress,
 	)