Use TokenDecimals in on chain reader

Signed-off-by: asoliman <[email protected]>

commit/factory.go

@@ -99,6 +99,7 @@ func (p *PluginFactory) NewReportingPlugin(config ocr3types.ReportingPluginConfi
 		onChainTokenPricesReader = reader.NewOnchainTokenPricesReader(
 			tokenPricesCr,
 			offchainConfig.PriceSources,
+			offchainConfig.TokenDecimals,
 		)
 	}
 

internal/reader/onchain_prices_reader.go

@@ -27,15 +27,18 @@ type OnchainTokenPricesReader struct {
 	// Reader for the chain that will have the token prices on-chain
 	ContractReader commontyps.ContractReader
 	PriceSources   map[types.Account]pluginconfig.ArbitrumPriceSource
+	TokenDecimals  map[types.Account]uint8
 }
 
 func NewOnchainTokenPricesReader(
 	contractReader commontyps.ContractReader,
 	priceSources map[types.Account]pluginconfig.ArbitrumPriceSource,
+	tokenDecimals map[types.Account]uint8,
 ) *OnchainTokenPricesReader {
 	return &OnchainTokenPricesReader{
 		ContractReader: contractReader,
 		PriceSources:   priceSources,
+		TokenDecimals:  tokenDecimals,
 	}
 }
 
@@ -66,12 +69,12 @@ func (pr *OnchainTokenPricesReader) GetTokenPricesUSD(
 			if err != nil {
 				return fmt.Errorf("failed to get token price for %s: %w", token, err)
 			}
-			decimals, err := pr.getFeedDecimals(ctx, token)
-			if err != nil {
+			decimals, ok := pr.TokenDecimals[token]
+			if !ok {
 				return fmt.Errorf("failed to get decimals for %s: %w", token, err)
 			}
 
-			prices[idx] = calculateUsdPer1e18TokenAmount(rawTokenPrice, *decimals)
+			prices[idx] = calculateUsdPer1e18TokenAmount(rawTokenPrice, decimals)
 			return nil
 		})
 	}
@@ -111,24 +114,6 @@ func (pr *OnchainTokenPricesReader) getRawTokenPrice(ctx context.Context, token
 	return latestRoundData.Answer, nil
 }
 
-func (pr *OnchainTokenPricesReader) getFeedDecimals(ctx context.Context, token types.Account) (*uint8, error) {
-	var decimals *uint8
-	if err :=
-		pr.ContractReader.GetLatestValue(
-			ctx,
-			consts.ContractNamePriceAggregator,
-			consts.MethodNameGetDecimals,
-			primitives.Unconfirmed,
-			nil,
-			&decimals,
-			//boundContract,
-		); err != nil {
-		return nil, fmt.Errorf("decimals call failed for token %s: %w", token, err)
-	}
-
-	return decimals, nil
-}
-
 // Input price is USD per full token, with 18 decimal precision
 // Result price is USD per 1e18 of smallest token denomination, with 18 decimal precision
 // Examples:

pluginconfig/commit.go

@@ -94,8 +94,15 @@ type CommitOffchainConfig struct {
 
 	// PriceSources is a map of Arbitrum price sources for each token.
 	// Note that the token address is that on the remote chain.
-	PriceSources  map[types.Account]ArbitrumPriceSource `json:"priceSources"`
-	TokenDecimals map[types.Account]uint8               `json:"decimals"`
+	PriceSources map[types.Account]ArbitrumPriceSource `json:"priceSources"`
+
+	// TokenDecimals is a map of token decimals for each token.
+	// As **not** each node supports both the
+	// 1. Token price feed chain (where we get the token price in USD)
+	// 2. Destination chain (where we can get the token decimals from PriceRegistry).
+	// So to be able to calculate the effective price we need both token decimals.
+	// This is why we need to store the token decimals in the config.
+	TokenDecimals map[types.Account]uint8 `json:"decimals"`
 
 	// TokenPriceChainSelector is the chain selector for the chain on which
 	// the token prices are read from.