monitoring: add prometheus monitoring

add init metrics service which uses prometheus;
add configuration for metrics service;
add monitoring metrics for blockchain,rpc,server;

pkg/rpc/prometheus.go

@@ -0,0 +1,119 @@
+package rpc
+
+import "github.com/prometheus/client_golang/prometheus"
+
+// Metrics used in monitoring service.
+var (
+	getbestblockhashCalled = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Help:      "Number of calls to getbestblockhash rpc endpoint",
+			Name:      "getbestblockhash_called",
+			Namespace: "neogo",
+		},
+	)
+
+	getbestblockCalled = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Help:      "Number of calls to getbestblock rpc endpoint",
+			Name:      "getbestblock_called",
+			Namespace: "neogo",
+		},
+	)
+
+	getblockcountCalled = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Help:      "Number of calls to getblockcount rpc endpoint",
+			Name:      "getblockcount_called",
+			Namespace: "neogo",
+		},
+	)
+
+	getblockHashCalled = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Help:      "Number of calls to getblockhash rpc endpoint",
+			Name:      "getblockhash_called",
+			Namespace: "neogo",
+		},
+	)
+
+	getconnectioncountCalled = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Help:      "Number of calls to getconnectioncount rpc endpoint",
+			Name:      "getconnectioncount_called",
+			Namespace: "neogo",
+		},
+	)
+
+	getversionCalled = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Help:      "Number of calls to getversion rpc endpoint",
+			Name:      "getversion_called",
+			Namespace: "neogo",
+		},
+	)
+
+	getpeersCalled = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Help:      "Number of calls to getpeers rpc endpoint",
+			Name:      "getpeers_called",
+			Namespace: "neogo",
+		},
+	)
+
+	validateaddressCalled = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Help:      "Number of calls to validateaddress rpc endpoint",
+			Name:      "validateaddress_called",
+			Namespace: "neogo",
+		},
+	)
+
+	getassetstateCalled = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Help:      "Number of calls to getassetstate rpc endpoint",
+			Name:      "getassetstate_called",
+			Namespace: "neogo",
+		},
+	)
+
+	getaccountstateCalled = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Help:      "Number of calls to getaccountstate rpc endpoint",
+			Name:      "getaccountstate_called",
+			Namespace: "neogo",
+		},
+	)
+
+	getrawtransactionCalled = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Help:      "Number of calls to getrawtransaction rpc endpoint",
+			Name:      "getrawtransaction_called",
+			Namespace: "neogo",
+		},
+	)
+
+	sendrawtransactionCalled = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Help:      "Number of calls to sendrawtransaction rpc endpoint",
+			Name:      "sendrawtransaction_called",
+			Namespace: "neogo",
+		},
+	)
+)
+
+func init() {
+	prometheus.MustRegister(
+		getbestblockhashCalled,
+		getbestblockCalled,
+		getblockcountCalled,
+		getblockHashCalled,
+		getconnectioncountCalled,
+		getversionCalled,
+		getpeersCalled,
+		validateaddressCalled,
+		getassetstateCalled,
+		getaccountstateCalled,
+		getrawtransactionCalled,
+		sendrawtransactionCalled,
+	)
+}