package main import ( "io/ioutil" "log" "path/filepath" "time" "github.com/conformal/btcrpcclient" "github.com/conformal/btcutil" "github.com/conformal/btcwire" ) // This example demonstrates a connection to the bitcoin network // by using websockets via btcd, use of notifications and an rpc // call to getblockcount. // // Install and run btcd: // $ go get github.com/conformal/btcd/... // $ btcd -u rpcuser -P rpcpass // // Install btcrpcclient: // $ go get github.com/conformal/btcrpcclient // // Run this example: // $ go run websocket-example.go // func main() { // Only override the handlers for notifications you care about. // Also note most of these handlers will only be called if you register // for notifications. See the documentation of the btcrpcclient // NotificationHandlers type for more details about each handler. ntfnHandlers := btcrpcclient.NotificationHandlers{ OnBlockConnected: func(hash *btcwire.ShaHash, height int32) { log.Printf("Block connected: %v (%d)", hash, height) }, OnBlockDisconnected: func(hash *btcwire.ShaHash, height int32) { log.Printf("Block disconnected: %v (%d)", hash, height) }, } // Connect to local btcd RPC server using websockets. btcdHomeDir := btcutil.AppDataDir("btcd", false) certs, err := ioutil.ReadFile(filepath.Join(btcdHomeDir, "rpc.cert")) if err != nil { log.Fatal(err) } connCfg := &btcrpcclient.ConnConfig{ Host: "localhost:8334", Endpoint: "ws", User: "rpcuser", Pass: "rpcpass", Certificates: certs, } client, err := btcrpcclient.New(connCfg, &ntfnHandlers) if err != nil { log.Fatal(err) } // Register for block connect and disconnect notifications. if err := client.NotifyBlocks(); err != nil { log.Fatal(err) } log.Println("NotifyBlocks: Registration Complete") // Get the current block count. blockCount, err := client.GetBlockCount() if err != nil { log.Fatal(err) } log.Printf("Block count: %d", blockCount) // For this example gracefully shutdown the client after 10 seconds. // Ordinarily when to shutdown the client is highly application // specific. log.Println("Client shutdown in 10 seconds...") time.AfterFunc(time.Second*10, func() { log.Println("Client shutting down...") client.Shutdown() log.Println("Client shutdown complete.") }) // Wait until the client either shuts down gracefully (or the user // terminates the process with Ctrl+C). client.WaitForShutdown() }