cli: add getBlock command

cli.go

@@ -27,6 +27,7 @@ func (cli *CLI) printUsage() {
 	fmt.Println("  getAddress -pubKey PUBKEY - convert pubKey to address")
 	fmt.Println("  getPubKeyHash -address Address - get pubKeyHash of an address")
 	fmt.Println("  validateAddress -addr Address - validate an address")
+	fmt.Println("  getBlock -hash BlockHash - get a block with BlockHash")
 }
 
 func (cli *CLI) validateArgs() {
@@ -58,6 +59,7 @@ func (cli *CLI) Run() {
 	getAddressCmd := flag.NewFlagSet("getAddress", flag.ExitOnError)
 	getPubKeyHashCmd := flag.NewFlagSet("getPubKeyHash", flag.ExitOnError)
 	validateAddrCmd := flag.NewFlagSet("validateAddress", flag.ExitOnError)
+	getBlockCmd := flag.NewFlagSet("getBlock", flag.ExitOnError)
 
 	getBalanceAddress := getBalanceCmd.String("address", "", "The address to get balance for")
 	createBlockchainAddress := createBlockchainCmd.String("address", "", "The address to send genesis block reward to")
@@ -69,6 +71,7 @@ func (cli *CLI) Run() {
 	pubKey := getAddressCmd.String("pubKey", "", "the key where address generated")
 	pubKeyAddress := getPubKeyHashCmd.String("address", "", "the pub address")
 	address := validateAddrCmd.String("addr", "", "the public address")
+	blockHash := getBlockCmd.String("hash", "", "the block hash")
 
 	switch os.Args[1] {
 	case "getbalance":
@@ -131,6 +134,11 @@ func (cli *CLI) Run() {
 		if err != nil {
 			log.Panic(err)
 		}
+	case "getBlock":
+		err := getBlockCmd.Parse(os.Args[2:])
+		if err != nil {
+			log.Panic(err)
+		}
 	default:
 		cli.printUsage()
 		os.Exit(1)
@@ -217,4 +225,13 @@ func (cli *CLI) Run() {
 		cli.validateAddr(*address)
 	}
 
+	if getBlockCmd.Parsed() {
+		if *blockHash == "" {
+			getBlockCmd.Usage()
+			os.Exit(1)
+		}
+
+		cli.printBlock(*blockHash, nodeID)
+	}
+
 }

cli_printchain.go

@@ -31,3 +31,32 @@ func (cli *CLI) printChain(nodeID string) {
 		}
 	}
 }
+
+func (cli *CLI) printBlock(blockHash, nodeID string) {
+	bc := NewBlockchain(nodeID)
+	defer bc.db.Close()
+
+	bci := bc.Iterator()
+
+	for {
+		block := bci.Next()
+
+		hash := fmt.Sprintf("%x", block.Hash)
+		if hash == blockHash {
+			fmt.Printf("============ Block %x ============\n", block.Hash)
+			fmt.Printf("Height: %d\n", block.Height)
+			fmt.Printf("Prev. block: %x\n", block.PrevBlockHash)
+			fmt.Printf("Created at : %s\n", time.Unix(block.Timestamp, 0))
+			pow := NewProofOfWork(block)
+			fmt.Printf("PoW: %s\n\n", strconv.FormatBool(pow.Validate()))
+			for _, tx := range block.Transactions {
+				fmt.Println(tx)
+			}
+			fmt.Printf("\n\n")
+		}
+
+		if len(block.PrevBlockHash) == 0 {
+			break
+		}
+	}
+}