handling too many requests error and storing logs received to retry i…

…n the next iteration (#159)

scanner/providers/farcaster/provider.go

@@ -238,7 +238,10 @@ func (p *FarcasterProvider) ScanLogsIDRegistry(ctx context.Context, fromBlock, t
 		web3.LOG_TOPIC_FARCASTER_REGISTER,
 	)
 	if err != nil {
-		return nil, 0, false, err
+		if !errors.Is(err, web3.ErrTooManyRequests) {
+			return nil, 0, false, err
+		}
+		log.Debug("too many requests error, handling scanned logs")
 	}
 	// encode the number of new registers
 	newFIDs := make(map[uint64]common.Address, 0)

scanner/providers/web3/errors.go

@@ -7,6 +7,7 @@ var (
 	ErrConnectingToWeb3Client = fmt.Errorf("client not set")
 	ErrInitializingContract   = fmt.Errorf("error initializing token contract")
 	ErrScanningTokenLogs      = fmt.Errorf("error scanning token logs")
+	ErrTooManyRequests        = fmt.Errorf("web3 endpoint returns too many requests")
 	ErrParsingTokenLogs       = fmt.Errorf("error parsing token logs")
 	ErrGettingTotalSupply     = fmt.Errorf("error getting total supply")
 )

scanner/providers/web3/web3_provider.go

@@ -134,6 +134,11 @@ func RangeOfLogs(ctx context.Context, client *ethclient.Client, addr common.Addr
 					log.Warnf("too much results on query, decreasing blocks to %d", blocksRange)
 					continue
 				}
+				// if error is about too many requests, return the logs scanned
+				// until now and the last block scanned with an specific error
+				if strings.Contains(strings.ToLower(err.Error()), "too many requests") {
+					return finalLogs, fromBlock, false, errors.Join(ErrTooManyRequests, fmt.Errorf("%s: %w", addr.Hex(), err))
+				}
 				return finalLogs, fromBlock, false, errors.Join(ErrScanningTokenLogs, fmt.Errorf("%s: %w", addr.Hex(), err))
 			}
 			// if there are logs, add them to the final list and update the