feat: check for previous height when querying

pkg/http/http.go

@@ -33,6 +33,7 @@ func NewClient(logger *zerolog.Logger, chain string, tracer trace.Tracer) *Clien
 func (c *Client) Get(
 	url string,
 	target interface{},
+	predicate types.HTTPPredicate,
 	ctx context.Context,
 ) (types.QueryInfo, http.Header, error) {
 	childCtx, span := c.tracer.Start(ctx, "HTTP request")
@@ -71,6 +72,10 @@ func (c *Client) Get(
 
 	c.logger.Debug().Str("url", url).Dur("duration", time.Since(start)).Msg("Query is finished")
 
+	if predicateErr := predicate(res); predicateErr != nil {
+		return queryInfo, res.Header, predicateErr
+	}
+
 	err = json.NewDecoder(res.Body).Decode(target)
 	queryInfo.Success = err == nil
 

pkg/price_fetchers/coingecko/coingecko.go

@@ -49,7 +49,7 @@ func (c *Coingecko) FetchPrices(
 	url := fmt.Sprintf("https://api.coingecko.com/api/v3/simple/price?ids=%s&vs_currencies=usd", ids)
 
 	var response Response
-	queryInfo, _, err := c.Client.Get(url, &response, childCtx)
+	queryInfo, _, err := c.Client.Get(url, &response, types.HTTPPredicateAlwaysPass(), childCtx)
 
 	if err != nil {
 		c.Logger.Error().Err(err).Msg("Could not get rate")

pkg/tendermint/tendermint.go

@@ -502,7 +502,20 @@ func (rpc *RPC) Get(
 	target interface{},
 	ctx context.Context,
 ) (types.QueryInfo, error) {
-	info, header, err := rpc.Client.Get(url, target, ctx)
+	rpc.Mutex.Lock()
+	previousHeight, found := rpc.LastHeight[url]
+	if !found {
+		previousHeight = 0
+	}
+	rpc.Mutex.Unlock()
+
+	info, header, err := rpc.Client.Get(
+		url,
+		target,
+		types.HTTPPredicateCheckHeightAfter(previousHeight),
+		ctx,
+	)
+
 	if err != nil {
 		return info, err
 	}

pkg/types/http_predicate.go

@@ -0,0 +1,34 @@
+package types
+
+import (
+	"fmt"
+	"main/pkg/utils"
+	"net/http"
+)
+
+type HTTPPredicate func(response *http.Response) error
+
+func HTTPPredicateAlwaysPass() HTTPPredicate {
+	return func(response *http.Response) error {
+		return nil
+	}
+}
+
+func HTTPPredicateCheckHeightAfter(prevHeight int64) HTTPPredicate {
+	return func(response *http.Response) error {
+		currentHeight, err := utils.GetBlockHeightFromHeader(response.Header)
+		if err != nil {
+			return err
+		}
+
+		if prevHeight > currentHeight {
+			return fmt.Errorf(
+				"previous height (%d) is bigger than the current height (%d)",
+				prevHeight,
+				currentHeight,
+			)
+		}
+
+		return nil
+	}
+}