Improve RPC per-identifier metrics registration.

	m.PrometheusScope.Timer("overall_latency_ms").Record(elapsed)

	// Per-endpoint stats.

	m.PrometheusScope.Counter("Rpc_count").Inc(1)

	m.PrometheusScope.Counter("Rpc_recv_bytes").Inc(recvBytes)

	m.PrometheusScope.Counter("Rpc_sent_bytes").Inc(sentBytes)

	m.PrometheusScope.Timer("Rpc_latency_ms").Record(elapsed)

	// Per-endpoint, per-RPC ID stats.

	var taggedScope tally.Scope

	if id != "" {

		taggedScope = m.PrometheusScope.Tagged(map[string]string{"rpc_id": id})

	taggedScope := m.PrometheusScope.Tagged(map[string]string{"rpc_id": id})

	taggedScope.Counter("Rpc_count").Inc(1)

	taggedScope.Counter("Rpc_recv_bytes").Inc(recvBytes)

	taggedScope.Counter("Rpc_sent_bytes").Inc(sentBytes)

	taggedScope.Timer("Rpc_latency_ms").Record(elapsed)

	}

	// Error stats if applicable.

	if isErr {

		m.PrometheusScope.Counter("overall_errors").Inc(1)

		m.PrometheusScope.Counter("overall_request_errors").Inc(1)

		m.PrometheusScope.Counter("Rpc_errors").Inc(1)

		if taggedScope != nil {

		taggedScope.Counter("Rpc_errors").Inc(1)

	}

}

}

func (m *LocalMetrics) ApiBefore(name string, elapsed time.Duration, isErr bool) {

	name = "before_" + strings.TrimPrefix(name, API_PREFIX)