Contract hist (#84)

Add ability to query contract historical state

cmd/show_contract_summary/main.go

@@ -7,6 +7,8 @@ import (
 
 	"fmt"
 
+	"math/big"
+
 	"github.com/8thlight/vulcanizedb/cmd"
 	"github.com/8thlight/vulcanizedb/pkg/geth"
 	"github.com/8thlight/vulcanizedb/pkg/watched_contracts"
@@ -15,14 +17,27 @@ import (
 func main() {
 	environment := flag.String("environment", "", "Environment name")
 	contractHash := flag.String("contract-hash", "", "Contract hash to show summary")
+	_blockNumber := flag.Int64("block-number", -1, "Block number of summary")
 	flag.Parse()
 	config := cmd.LoadConfig(*environment)
 	blockchain := geth.NewGethBlockchain(config.Client.IPCPath)
 	repository := cmd.LoadPostgres(config.Database)
-	contractSummary, err := watched_contracts.NewSummary(blockchain, repository, *contractHash)
+	blockNumber := requestedBlockNumber(_blockNumber)
+
+	contractSummary, err := watched_contracts.NewSummary(blockchain, repository, *contractHash, blockNumber)
 	if err != nil {
 		log.Fatalln(err)
 	}
 	output := watched_contracts.GenerateConsoleOutput(contractSummary)
 	fmt.Println(output)
 }
+
+func requestedBlockNumber(blockNumber *int64) *big.Int {
+	var _blockNumber *big.Int
+	if *blockNumber == -1 {
+		_blockNumber = nil
+	} else {
+		_blockNumber = big.NewInt(*blockNumber)
+	}
+	return _blockNumber
+}