hello world

ln/lnd.go

@@ -0,0 +1,149 @@
+package ln
+
+import (
+	"context"
+	"encoding/hex"
+	"io/ioutil"
+  "log"
+  "os"
+
+  "github.com/lightningnetwork/lnd/lnrpc"
+  "gopkg.in/macaroon.v2"
+  "github.com/lightningnetwork/lnd/macaroons"
+
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/credentials"
+)
+
+
+var stdOutLogger = log.New(os.Stdout, "", log.LstdFlags)
+
+// Invoice is a Lightning Network invoice and contains the typical invoice string and the payment hash.
+type Invoice struct {
+	ImplDepID string
+	PaymentHash string
+	PaymentRequest string
+}
+
+type LNDclient struct {
+	lndClient lnrpc.LightningClient
+	ctx       context.Context
+	conn      *grpc.ClientConn
+}
+
+// GenerateInvoice generates an invoice with the given price and memo.
+func (c LNDclient) GenerateInvoice(amount int64, memo string) (Invoice, error) {
+	result := Invoice{}
+
+	// Create the request and send it
+	invoice := lnrpc.Invoice{
+		Memo:  memo,
+		Value: amount,
+	}
+	stdOutLogger.Println("Creating invoice for a new API request")
+	res, err := c.lndClient.AddInvoice(c.ctx, &invoice)
+	if err != nil {
+		return result, err
+	}
+
+	result.ImplDepID = hex.EncodeToString(res.RHash)
+	result.PaymentHash = result.ImplDepID
+	result.PaymentRequest = res.PaymentRequest
+	return result, nil
+}
+
+// CheckInvoice takes an invoice ID and checks if the corresponding invoice was settled.
+// An error is returned if no corresponding invoice was found.
+// False is returned if the invoice isn't settled.
+func (c LNDclient) CheckInvoice(id string) (bool, error) {
+	// In the case of lnd, the ID is the hex encoded preimage hash.
+	plainHash, err := hex.DecodeString(id)
+	if err != nil {
+		return false, err
+	}
+
+	stdOutLogger.Printf("Checking invoice for hash %v\n", id)
+
+	// Get the invoice for that hash
+	paymentHash := lnrpc.PaymentHash{
+		RHash: plainHash,
+		// Hex encoded, must be exactly 32 byte
+		RHashStr: id,
+	}
+	invoice, err := c.lndClient.LookupInvoice(c.ctx, &paymentHash)
+	if err != nil {
+		return false, err
+	}
+
+	// Check if invoice was settled
+	if !invoice.GetSettled() {
+		return false, nil
+	}
+	return true, nil
+}
+
+func (c LNDclient) GetURIs() (bool, error) {
+  req := &lnrpc.GetInfoRequest{}
+  info, err := c.lndClient.GetInfo(c.ctx, req)
+	stdOutLogger.Println(info.Uris)
+  return true, err
+}
+
+
+// NewLNDclient creates a new LNDclient instance.
+func NewLNDclient(lndOptions LNDoptions) (LNDclient, error) {
+	result := LNDclient{}
+
+	// Set up a connection to the server.
+	creds, err := credentials.NewClientTLSFromFile(lndOptions.CertFile, "")
+	if err != nil {
+		return result, err
+	}
+  opts := []grpc.DialOption{
+    grpc.WithTransportCredentials(creds),
+  }
+
+	macaroonData, err := ioutil.ReadFile(lndOptions.MacaroonFile)
+	if err != nil {
+		return result, err
+	}
+  mac := &macaroon.Macaroon{}
+	if err = mac.UnmarshalBinary(macaroonData); err != nil {
+    return result, err
+  }
+
+  macCred := macaroons.NewMacaroonCredential(mac)
+  opts = append(opts, grpc.WithPerRPCCredentials(macCred))
+
+  conn, err := grpc.Dial(lndOptions.Address, opts...)
+  if err != nil {
+    return result, err
+  }
+
+	c := lnrpc.NewLightningClient(conn)
+
+	result = LNDclient{
+		conn:      conn,
+		ctx:       context.Background(),
+		lndClient: c,
+	}
+
+	return result, nil
+}
+
+// LNDoptions are the options for the connection to the lnd node.
+type LNDoptions struct {
+	// Address of your LND node, including the port.
+	// Optional ("localhost:10009" by default).
+	Address string
+	// Path to the "tls.cert" file that your LND node uses.
+	// Optional ("tls.cert" by default).
+	CertFile string
+	// Path to the macaroon file that your LND node uses.
+	// "invoice.macaroon" if you only use the GenerateInvoice() and CheckInvoice() methods
+	// (required by the middleware in the package "wall").
+	// "admin.macaroon" if you use the Pay() method (required by the client in the package "pay").
+	// Optional ("invoice.macaroon" by default).
+	MacaroonFile string
+}
+