add PrintHTML method to chain

block.go

@@ -3,7 +3,10 @@ package bc
 import (
 	"bytes"
 	"encoding/gob"
+	"fmt"
 	"log"
+	"strconv"
+	"strings"
 	"time"
 )
 
@@ -71,3 +74,20 @@ func DeserializeBlock(d []byte) *Block {
 
 	return &block
 }
+
+func (b *Block) PrintHTML(detail bool) string {
+	var lines []string
+	lines = append(lines, fmt.Sprintf("<h2>Block <a href=\"/block/%x\">%x</a> </h2>", b.Hash, b.Hash))
+	lines = append(lines, fmt.Sprintf("Height: %d</br>", b.Height))
+	lines = append(lines, fmt.Sprintf("Prev. block: <a href=\"/block/%x\">%x</a></br>", b.PrevBlockHash, b.PrevBlockHash))
+	lines = append(lines, fmt.Sprintf("Created at : %s</br>", time.Unix(b.Timestamp, 0)))
+	pow := NewProofOfWork(b)
+	lines = append(lines, fmt.Sprintf("PoW: %s</br></br>", strconv.FormatBool(pow.Validate())))
+	if detail {
+		for _, tx := range b.Transactions {
+			lines = append(lines, tx.PrintHTML())
+		}
+	}
+	lines = append(lines, fmt.Sprintf("</br></br>"))
+	return strings.Join(lines, "\n")
+}

blockchain.go

@@ -8,6 +8,7 @@ import (
 	"fmt"
 	"log"
 	"os"
+	"strings"
 
 	"github.com/boltdb/bolt"
 )
@@ -358,3 +359,20 @@ func dbExists(dbFile string) bool {
 
 	return true
 }
+
+func (bc *Blockchain) PrintHTML() string {
+	var lines []string
+	bci := bc.Iterator()
+
+	for {
+		block := bci.Next()
+
+		lines = append(lines, block.PrintHTML(false))
+
+		if len(block.PrevBlockHash) == 0 {
+			break
+		}
+	}
+	return strings.Join(lines, "\n")
+
+}

transaction.go

@@ -249,3 +249,32 @@ func DeserializeTransaction(data []byte) Transaction {
 
 	return transaction
 }
+
+func (tx Transaction) PrintHTML() string {
+	var lines []string
+
+	lines = append(lines, fmt.Sprintf("<h4> Transaction %x:</h4>", tx.ID))
+
+	for i, input := range tx.Vin {
+
+		pubKeyHash := HashPubKey(input.PubKey)
+		versionedPayload := append([]byte{version}, pubKeyHash...)
+		fullPayload := append(versionedPayload, checksum(versionedPayload)...)
+
+		lines = append(lines, fmt.Sprintf("<div>Input %d:</div>", i))
+		lines = append(lines, fmt.Sprintf("<div style=\"text-indent:2em;\">TXID:      %x</div>", input.Txid))
+		lines = append(lines, fmt.Sprintf("<div style=\"text-indent:2em;\">Out:       %d</div>", input.Vout))
+		lines = append(lines, fmt.Sprintf("<div style=\"text-indent:2em;\">Signature: %x</div>", input.Signature))
+		lines = append(lines, fmt.Sprintf("<div style=\"text-indent:2em;\">PubKey:    %x</div>", input.PubKey))
+		lines = append(lines, fmt.Sprintf("<div style=\"text-indent:2em;\">Addr  :    %s</div>", Base58Encode(fullPayload)))
+	}
+
+	for i, output := range tx.Vout {
+		lines = append(lines, fmt.Sprintf("<div>Output %d:</div>", i))
+		lines = append(lines, fmt.Sprintf("<div style=\"text-indent:2em;\">Value:  %d</div>", output.Value))
+		lines = append(lines, fmt.Sprintf("<div style=\"text-indent:2em;\">Script: %x</div>", output.PubKeyHash))
+		lines = append(lines, fmt.Sprintf("<div style=\"text-indent:2em;\">Addr  : %s</div>", output.Address))
+	}
+
+	return strings.Join(lines, "")
+}