[lbry] examples: update lbcdblocknotify to support Stratum

rpcclient/examples/lbcdblocknotify/README.md

@@ -12,22 +12,33 @@ The first step is to clone the lbcd package:
 $ git clone github.com/lbryio/lbcd
 ```
 
-Next, navigate to the example's directory and modify the `main.go` source to
-specify the correct RPC username and password for the RPC server:
+Display available options:
 
 ```bash
-$ cd rpcclient/examples/lbcdblocknotify
+$ go run . -h
+
+  -coinid string
+        Coin ID (default "1425")
+  -rpcpass string
+        LBCD RPC password (default "rpcpass")
+  -rpcserver string
+        LBCD RPC server (default "localhost:9245")
+  -rpcuser string
+        LBCD RPC username (default "rpcuser")
+  -stratum string
+        Stratum server (default "lbrypool.net:3334")
+  -stratumpass string
+        Stratum server password (default "password")
 ```
 
-```Go
-	User: "yourrpcuser",
-	Pass: "yourrpcpass",
-```
-
-Finally, run it with:
+Start the program:
 
 ```bash
-$ go run .
+$ go run . -stratumpass <STRATUM PASSWD> -rpcuser <RPC USERNAME> -rpcpass <RPC PASSWD>
+
+2022/01/10 23:16:21 NotifyBlocks: Registration Complete
+2022/01/10 23:16:21 Block count: 1093112
+...
 ```
 
 ## License

rpcclient/examples/lbcdblocknotify/main.go

@@ -5,8 +5,11 @@
 package main
 
 import (
+	"flag"
+	"fmt"
 	"io/ioutil"
 	"log"
+	"net"
 	"path/filepath"
 
 	"github.com/lbryio/lbcd/rpcclient"
@@ -14,19 +17,52 @@ import (
 	"github.com/lbryio/lbcutil"
 )
 
+func send(stratum, stratumPass, coinid, blockHash string) error {
+	addr, err := net.ResolveTCPAddr("tcp", stratum)
+	if err != nil {
+		return fmt.Errorf("can't resolve addr: %w", err)
+	}
+
+	conn, err := net.DialTCP("tcp", nil, addr)
+	if err != nil {
+		return fmt.Errorf("can't dial tcp: %w", err)
+	}
+	defer conn.Close()
+
+	msg := fmt.Sprintf(`{"id":1,"method":"mining.update_block","params":[%q,%q,%q]}`,
+		stratumPass, coinid, blockHash)
+
+	_, err = conn.Write([]byte(msg))
+	if err != nil {
+		return fmt.Errorf("can't write message: %w", err)
+	}
+
+	return nil
+}
+
 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 rpcclient
-	// NotificationHandlers type for more details about each handler.
+
+	var (
+		coinid      = flag.String("coinid", "1425", "Coin ID")
+		stratum     = flag.String("stratum", "lbrypool.net:3334", "Stratum server")
+		stratumPass = flag.String("stratumpass", "password", "Stratum server password")
+		rpcserver   = flag.String("rpcserver", "localhost:9245", "LBCD RPC server")
+		rpcuser     = flag.String("rpcuser", "rpcuser", "LBCD RPC username")
+		rpcpass     = flag.String("rpcpass", "rpcpass", "LBCD RPC password")
+	)
+
+	flag.Parse()
+
 	ntfnHandlers := rpcclient.NotificationHandlers{
 		OnFilteredBlockConnected: func(height int32, header *wire.BlockHeader, txns []*lbcutil.Tx) {
-			log.Printf("Block connected: %v (%d) %v",
-				header.BlockHash(), height, header.Timestamp)
-		},
-		OnFilteredBlockDisconnected: func(height int32, header *wire.BlockHeader) {
-			log.Printf("Block disconnected: %v (%d) %v",
-				header.BlockHash(), height, header.Timestamp)
+
+			blockHash := header.BlockHash().String()
+
+			log.Printf("Block connected: %v (%d) %v", blockHash, height, header.Timestamp)
+
+			if err := send(*stratum, *stratumPass, *coinid, blockHash); err != nil {
+				log.Printf("ERROR: failed to notify stratum: %s", err)
+			}
 		},
 	}
 
@@ -34,30 +70,30 @@ func main() {
 	lbcdHomeDir := lbcutil.AppDataDir("lbcd", false)
 	certs, err := ioutil.ReadFile(filepath.Join(lbcdHomeDir, "rpc.cert"))
 	if err != nil {
-		log.Fatal(err)
+		log.Fatalf("can't read lbcd certificate: %s", err)
 	}
 	connCfg := &rpcclient.ConnConfig{
-		Host:         "localhost:9245",
+		Host:         *rpcserver,
 		Endpoint:     "ws",
-		User:         "rpcuser",
-		Pass:         "rpcpass",
+		User:         *rpcuser,
+		Pass:         *rpcpass,
 		Certificates: certs,
 	}
 	client, err := rpcclient.New(connCfg, &ntfnHandlers)
 	if err != nil {
-		log.Fatalln(err)
+		log.Fatalf("can't create rpc client: %s", err)
 	}
 
 	// Register for block connect and disconnect notifications.
-	if err := client.NotifyBlocks(); err != nil {
-		log.Fatalln(err)
+	if err = client.NotifyBlocks(); err != nil {
+		log.Fatalf("can't register block notification: %s", err)
 	}
-	log.Println("NotifyBlocks: Registration Complete")
+	log.Printf("NotifyBlocks: Registration Complete")
 
 	// Get the current block count.
 	blockCount, err := client.GetBlockCount()
 	if err != nil {
-		log.Fatal(err)
+		log.Fatalf("can't get block count: %s", err)
 	}
 	log.Printf("Block count: %d", blockCount)