package core import ( "fmt" "reflect" "github.com/ethereum/go-ethereum" "github.com/ethereum/go-ethereum/core/types" "github.com/ethereum/go-ethereum/ethclient" "golang.org/x/net/context" ) type GethBlockchain struct { client *ethclient.Client observers []BlockchainObserver subscription ethereum.Subscription } func NewGethBlockchain(ipcPath string) *GethBlockchain { fmt.Printf("Creating Geth Blockchain to: %s\n", ipcPath) blockchain := GethBlockchain{} client, _ := ethclient.Dial(ipcPath) blockchain.client = client return &blockchain } func (blockchain GethBlockchain) notifyObservers(gethBlock *types.Block) { block := GethBlockToCoreBlock(gethBlock) for _, observer := range blockchain.observers { observer.NotifyBlockAdded(block) } } func (blockchain *GethBlockchain) RegisterObserver(observer BlockchainObserver) { fmt.Printf("Registering observer: %v\n", reflect.TypeOf(observer)) blockchain.observers = append(blockchain.observers, observer) } func (blockchain *GethBlockchain) SubscribeToEvents() { headers := make(chan *types.Header, 10) myContext := context.Background() sub, _ := blockchain.client.SubscribeNewHead(myContext, headers) blockchain.subscription = sub for header := range headers { gethBlock, _ := blockchain.client.BlockByNumber(myContext, header.Number) blockchain.notifyObservers(gethBlock) } }