From 51ab23dd3ab288bc50339e2bca409f6f2a525ebb Mon Sep 17 00:00:00 2001
From: Eric Meyer <emeyer@8thlight.com>
Date: Mon, 23 Oct 2017 15:02:56 -0500
Subject: [PATCH] Output the number of transactions when logging a new block

---
 core/block.go                       |  3 ++-
 core/blockchain_logging_observer.go |  2 +-
 core/geth_blockchain.go             | 19 +++++++++++++------
 3 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/core/block.go b/core/block.go
index 3eb57f06..ae0647fa 100644
--- a/core/block.go
+++ b/core/block.go
@@ -3,5 +3,6 @@ package core
 import "math/big"
 
 type Block struct {
-	Number *big.Int
+	Number               *big.Int
+	NumberOfTransactions int
 }
diff --git a/core/blockchain_logging_observer.go b/core/blockchain_logging_observer.go
index 61eab638..9602b634 100644
--- a/core/blockchain_logging_observer.go
+++ b/core/blockchain_logging_observer.go
@@ -5,5 +5,5 @@ import "fmt"
 type BlockchainLoggingObserver struct{}
 
 func (blockchainObserver BlockchainLoggingObserver) NotifyBlockAdded(block Block) {
-	fmt.Printf("New block was added: %d\n", block.Number)
+	fmt.Printf("New block was added: %d, %d\n", block.Number, block.NumberOfTransactions)
 }
diff --git a/core/geth_blockchain.go b/core/geth_blockchain.go
index 305e723b..986579d8 100644
--- a/core/geth_blockchain.go
+++ b/core/geth_blockchain.go
@@ -21,12 +21,18 @@ func NewGethBlockchain(ipcPath string) *GethBlockchain {
 	blockchain.client = client
 	return &blockchain
 }
-func (blockchain GethBlockchain) notifyObservers(header *types.Header) {
-	block := Block{Number: header.Number}
+func (blockchain GethBlockchain) notifyObservers(getBlock *types.Block) {
+	block := convertBlock(getBlock)
 	for _, observer := range blockchain.observers {
 		observer.NotifyBlockAdded(block)
 	}
 }
+func convertBlock(gethBlock *types.Block) Block {
+	return Block{
+		Number:               gethBlock.Number(),
+		NumberOfTransactions: len(gethBlock.Transactions()),
+	}
+}
 
 func (blockchain *GethBlockchain) RegisterObserver(observer BlockchainObserver) {
 	fmt.Printf("Registering observer: %v\n", reflect.TypeOf(observer))
@@ -34,10 +40,11 @@ func (blockchain *GethBlockchain) RegisterObserver(observer BlockchainObserver)
 }
 
 func (blockchain *GethBlockchain) SubscribeToEvents() {
-	blocks := make(chan *types.Header, 10)
+	headers := make(chan *types.Header, 10)
 	myContext := context.Background()
-	blockchain.client.SubscribeNewHead(myContext, blocks)
-	for block := range blocks {
-		blockchain.notifyObservers(block)
+	blockchain.client.SubscribeNewHead(myContext, headers)
+	for header := range headers {
+		gethBlock, _ := blockchain.client.BlockByNumber(myContext, header.Number)
+		blockchain.notifyObservers(gethBlock)
 	}
 }