feat: add price metric (#15)

main.go

@@ -282,6 +282,14 @@ func Handler(w http.ResponseWriter, r *http.Request, manager *Manager, log *zero
 		[]string{"chain"},
 	)
 
+	tokenPriceGauge := prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Name: "cosmos_validators_exporter_price",
+			Help: "Price of 1 token in display denom in USD",
+		},
+		[]string{"chain"},
+	)
+
 	registry := prometheus.NewRegistry()
 	registry.MustRegister(queriesCountGauge)
 	registry.MustRegister(queriesSuccessfulGauge)
@@ -312,8 +320,9 @@ func Handler(w http.ResponseWriter, r *http.Request, manager *Manager, log *zero
 	registry.MustRegister(denomCoefficientGauge)
 	registry.MustRegister(activeSetSizeGauge)
 	registry.MustRegister(activeSetTokensGauge)
+	registry.MustRegister(tokenPriceGauge)
 
-	validators := manager.GetAllValidators()
+	validators, currencies := manager.GetAllValidators()
 	for _, validator := range validators {
 		queriesCountGauge.With(prometheus.Labels{
 			"chain":   validator.Chain,
@@ -531,6 +540,12 @@ func Handler(w http.ResponseWriter, r *http.Request, manager *Manager, log *zero
 		}).Set(float64(chain.DenomCoefficient))
 	}
 
+	for chain, price := range currencies {
+		tokenPriceGauge.With(prometheus.Labels{
+			"chain": chain,
+		}).Set(price)
+	}
+
 	h := promhttp.HandlerFor(registry, promhttp.HandlerOpts{})
 	h.ServeHTTP(w, r)
 

manager.go

@@ -21,10 +21,17 @@ func NewManager(config Config, logger *zerolog.Logger) *Manager {
 	}
 }
 
-func (m *Manager) GetAllValidators() []ValidatorQuery {
+func (m *Manager) GetAllValidators() ([]ValidatorQuery, map[string]float64) {
 	currenciesList := m.Config.GetCoingeckoCurrencies()
 	currenciesRates := m.Coingecko.FetchPrices(currenciesList)
 
+	currenciesRatesToChains := map[string]float64{}
+	for _, chain := range m.Config.Chains {
+		if rate, ok := currenciesRates[chain.CoingeckoCurrency]; ok {
+			currenciesRatesToChains[chain.Name] = rate
+		}
+	}
+
 	length := 0
 	for _, chain := range m.Config.Chains {
 		for range chain.Validators {
@@ -352,7 +359,7 @@ func (m *Manager) GetAllValidators() []ValidatorQuery {
 
 	wg.Wait()
 
-	return validators
+	return validators, currenciesRatesToChains
 }
 
 func (m *Manager) GetSelfDelegationsBalance(chain Chain, address string, rpc *RPC) (Balance, *QueryInfo, error) {