Serve API only via cli

cli/node/main.go

@@ -143,6 +143,42 @@ func cmdRun(c *cli.Context) error {
 	return nil
 }
 
+func cmdServeAPI(c *cli.Context) error {
+	cfg, err := parseCli(c)
+	if err != nil {
+		return tracerr.Wrap(fmt.Errorf("error parsing flags and config: %w", err))
+	}
+	node, err := node.NewNode(cfg.mode, cfg.node)
+	if err != nil {
+		return tracerr.Wrap(fmt.Errorf("error starting node: %w", err))
+	}
+	node.Start()
+
+	stopCh := make(chan interface{})
+
+	// catch ^C to send the stop signal
+	ossig := make(chan os.Signal, 1)
+	signal.Notify(ossig, os.Interrupt)
+	const forceStopCount = 3
+	go func() {
+		n := 0
+		for sig := range ossig {
+			if sig == os.Interrupt {
+				log.Info("Received Interrupt Signal")
+				stopCh <- nil
+				n++
+				if n == forceStopCount {
+					log.Fatalf("Received %v Interrupt Signals", forceStopCount)
+				}
+			}
+		}
+	}()
+	<-stopCh
+	node.Stop()
+
+	return nil
+}
+
 func cmdDiscard(c *cli.Context) error {
 	_cfg, err := parseCli(c)
 	if err != nil {
@@ -304,6 +340,12 @@ func main() {
 			Usage:   "Run the hermez-node in the indicated mode",
 			Action:  cmdRun,
 		},
+		{
+			Name:    "serveapi",
+			Aliases: []string{},
+			Usage:   "Serve the API only",
+			Action:  cmdServeAPI,
+		},
 		{
 			Name:    "discard",
 			Aliases: []string{},

config/config.go

@@ -44,6 +44,13 @@ type ForgeBatchGasCost struct {
 	L2Tx      uint64 `validate:"required"`
 }
 
+// CoordinatorAPI specifies the configuration parameters of the API in mode
+// coordinator
+type CoordinatorAPI struct {
+	// Coordinator enables the coordinator API endpoints
+	Coordinator bool
+}
+
 // Coordinator is the coordinator specific configuration.
 type Coordinator struct {
 	// ForgerAddress is the address under which this coordinator is forging
@@ -197,10 +204,7 @@ type Coordinator struct {
 		// ForgeBatch transaction.
 		ForgeBatchGasCost ForgeBatchGasCost `validate:"required"`
 	} `validate:"required"`
-	API struct {
-		// Coordinator enables the coordinator API endpoints
-		Coordinator bool
-	} `validate:"required"`
+	API   CoordinatorAPI `validate:"required"`
 	Debug struct {
 		// BatchPath if set, specifies the path where batchInfo is stored
 		// in JSON in every step/update of the pipeline
@@ -215,26 +219,29 @@ type Coordinator struct {
 	}
 }
 
-// Node is the hermez node configuration.
-type Node struct {
-	PriceUpdater struct {
-		// Interval between price updater calls
-		Interval Duration `valudate:"required"`
-		// URL of the token prices provider
-		URL string `valudate:"required"`
-		// Type of the API of the token prices provider
-		Type string `valudate:"required"`
-	} `validate:"required"`
-	StateDB struct {
-		// Path where the synchronizer StateDB is stored
-		Path string `validate:"required"`
-		// Keep is the number of checkpoints to keep
-		Keep int `validate:"required"`
-	} `validate:"required"`
+// NodeAPI specifies the configuration parameters of the API
+type NodeAPI struct {
+	// Address where the API will listen if set
+	Address string
+	// Explorer enables the Explorer API endpoints
+	Explorer bool
+	// UpdateMetricsInterval is the interval between updates of the
+	// API metrics
+	UpdateMetricsInterval Duration
+	// UpdateRecommendedFeeInterval is the interval between updates of the
+	// recommended fees
+	UpdateRecommendedFeeInterval Duration
+	// Maximum concurrent connections allowed between API and SQL
+	MaxSQLConnections int `validate:"required"`
+	// SQLConnectionTimeout is the maximum amount of time that an API request
+	// can wait to stablish a SQL connection
+	SQLConnectionTimeout Duration
+}
+
 // It's possible to use diferentiated SQL connections for read/write.
 // If the read configuration is not provided, the write one it's going to be used
 // for both reads and writes
-	PostgreSQL struct {
+type PostgreSQL struct {
 	// Port of the PostgreSQL write server
 	PortWrite int `validate:"required"`
 	// Host of the PostgreSQL write server
@@ -255,7 +262,38 @@ type Node struct {
 	PasswordRead string
 	// Name of the PostgreSQL read server database
 	NameRead string
+}
+
+// NodeDebug specifies debug configuration parameters
+type NodeDebug struct {
+	// APIAddress is the address where the debugAPI will listen if
+	// set
+	APIAddress string
+	// MeddlerLogs enables meddler debug mode, where unused columns and struct
+	// fields will be logged
+	MeddlerLogs bool
+	// GinDebugMode sets Gin-Gonic (the web framework) to run in
+	// debug mode
+	GinDebugMode bool
+}
+
+// Node is the hermez node configuration.
+type Node struct {
+	PriceUpdater struct {
+		// Interval between price updater calls
+		Interval Duration `valudate:"required"`
+		// URL of the token prices provider
+		URL string `valudate:"required"`
+		// Type of the API of the token prices provider
+		Type string `valudate:"required"`
 	} `validate:"required"`
+	StateDB struct {
+		// Path where the synchronizer StateDB is stored
+		Path string `validate:"required"`
+		// Keep is the number of checkpoints to keep
+		Keep int `validate:"required"`
+	} `validate:"required"`
+	PostgreSQL PostgreSQL `validate:"required"`
 	Web3       struct {
 		// URL is the URL of the web3 ethereum-node RPC server
 		URL string `validate:"required"`
@@ -286,37 +324,23 @@ type Node struct {
 		// TokenHEZ address
 		TokenHEZName string `validate:"required"`
 	} `validate:"required"`
-	API struct {
-		// Address where the API will listen if set
-		Address string
-		// Explorer enables the Explorer API endpoints
-		Explorer bool
-		// UpdateMetricsInterval is the interval between updates of the
-		// API metrics
-		UpdateMetricsInterval Duration
-		// UpdateRecommendedFeeInterval is the interval between updates of the
-		// recommended fees
-		UpdateRecommendedFeeInterval Duration
-		// Maximum concurrent connections allowed between API and SQL
-		MaxSQLConnections int `validate:"required"`
-		// SQLConnectionTimeout is the maximum amount of time that an API request
-		// can wait to stablish a SQL connection
-		SQLConnectionTimeout Duration
-	} `validate:"required"`
-	Debug struct {
-		// APIAddress is the address where the debugAPI will listen if
-		// set
-		APIAddress string
-		// MeddlerLogs enables meddler debug mode, where unused columns and struct
-		// fields will be logged
-		MeddlerLogs bool
-		// GinDebugMode sets Gin-Gonic (the web framework) to run in
-		// debug mode
-		GinDebugMode bool
-	}
+	API         NodeAPI     `validate:"required"`
+	Debug       NodeDebug   `validate:"required"`
 	Coordinator Coordinator `validate:"-"`
 }
 
+type APIServer struct {
+	API         NodeAPI    `validate:"required"`
+	PostgreSQL  PostgreSQL `validate:"required"`
+	Coordinator struct {
+		API struct {
+			// Coordinator enables the coordinator API endpoints
+			Coordinator bool
+		} `validate:"required"`
+	} `validate:"required"`
+	Debug NodeDebug `validate:"required"`
+}
+
 // Load loads a generic config.
 func Load(path string, cfg interface{}) error {
 	bs, err := ioutil.ReadFile(path) //nolint:gosec