multi: add pay invoice form, update infos

Add a payment invoice form in the service faucet.go and update the static files to show this feature. Rename package to avoid install a bin with name main. Update confirmations to wait in channel creation.
decred · Aug 6, 2019 · 1fb8968 · 1fb8968
1 parent 509d66e
commit 1fb8968
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Showing 3 changed files with 214 additions and 15 deletions.
diff --git a/faucet.go b/faucet.go
@@ -1,6 +1,7 @@
 package main
 
 import (
+	"context"
 	"encoding/hex"
 	"fmt"
 	"html/template"
@@ -33,6 +34,10 @@ const (
 	// minChannelSize is the smallest channel that the faucet will extend
 	// to a peer.
 	minChannelSize int64 = 50000
+
+	// maxPaymentAtoms is the larget payment amount in atoms that the faucet
+	// will pay to an invoice
+	maxPaymentAtoms int64 = 1000
 )
 
 // chanCreationError is an enum which describes the exact nature of an error
@@ -89,9 +94,22 @@ const (
 	// InvoiceTimeNotElapsed indicates minimum time to create a new invoice has not elapsed
 	InvoiceTimeNotElapsed
 
+	// PayInvoiceTimeNotElapsed indicates minimum time to pay a new invoice has not elapsed
+	PayInvoiceTimeNotElapsed
+
 	// InvoiceAmountTooHigh indicates the user tried to generate an invoice
 	// that was too expensive.
 	InvoiceAmountTooHigh
+
+	// ErrorDecodingPayReq indicates the user tried to input wrong invoice to create Payment Request
+	ErrorDecodingPayReq
+
+	// PaymentStreamError indicates that you get an error in the payment stream proccess
+	PaymentStreamError
+
+	// ErrorPaymentAmount indicates the user tried to pay an invoice with
+	// a value greater then the limit
+	ErrorPaymentAmount
 )
 
 var (
@@ -100,16 +118,27 @@ var (
 	// invoice in seconds.
 	GenerateInvoiceTimeout = time.Duration(60) * time.Second
 
+	// PayInvoiceTimeout represents the minimum time to pay a new
+	// invoice in seconds.
+	PayInvoiceTimeout = time.Duration(60) * time.Second
+
 	// GenerateInvoiceAction represents an action to generate invoice on post forms
 	GenerateInvoiceAction = "generateinvoice"
 
+	// PayInvoiceAction represents an action to pay invoice on post forms
+	PayInvoiceAction = "payinvoice"
+
 	// OpenChannelAction represents an action to open channel on post forms
 	OpenChannelAction = "openchannel"
-)
 
-// lastGeneratedInvoiceTime stores the last time an invoice generation was
-// attempted.
-var lastGeneratedInvoiceTime time.Time
+	// lastGeneratedInvoiceTime stores the last time an invoice generation was
+	// attempted.
+	lastGeneratedInvoiceTime time.Time
+
+	// lastPayInvoiceTime stores the last time an invoice payment was
+	// attempted.
+	lastPayInvoiceTime time.Time
+)
 
 // String returns a human readable string describing the chanCreationError.
 // This string is used in the templates in order to display the error to the
@@ -140,8 +169,17 @@ func (c chanCreationError) String() string {
 		return "Error generating Invoice"
 	case InvoiceTimeNotElapsed:
 		return "Please wait until you can generate a new invoice"
+	case PayInvoiceTimeNotElapsed:
+		return "Please wait until you can pay a new invoice"
 	case InvoiceAmountTooHigh:
 		return "Invoice amount too high"
+	case ErrorDecodingPayReq:
+		return "Error decoding payment request"
+	case PaymentStreamError:
+		return "Error on payment request, try again"
+	case ErrorPaymentAmount:
+		return fmt.Sprintf("The amount of invoice exceeds the limit of %d Atoms", maxPaymentAtoms)
+
 	default:
 		return fmt.Sprintf("%v", uint8(c))
 	}
@@ -400,11 +438,25 @@ type homePageContext struct {
 	// InvoicePaymentRequest the payment request generated by an invoice.
 	InvoicePaymentRequest string
 
+	// PayInvoiceRequest the pay request for an invoice.
+	PayInvoiceRequest string
+
+	// PayInvoiceAction action
+	PayInvoiceAction string
+
 	// OpenChannelAction indicates the form action to open a channel
 	OpenChannelAction string
 
 	// GenerateInvoiceAction indicates the form action to generate a new Invoice
 	GenerateInvoiceAction string
+
+	// Payment infos
+	PaymentDestination string
+	PaymentDescription string
+	PaymentAmount      string
+	PaymentHash        string
+	PaymentPreimage    string
+	PaymentHops        []*lnrpc.Hop
 }
 
 // fetchHomeState is helper functions that populates the homePageContext with
@@ -462,12 +514,13 @@ func (l *lightningFaucet) fetchHomeState() (*homePageContext, error) {
 		NumCoins:              dcrutil.Amount(walletBalance.ConfirmedBalance).ToCoin(),
 		GitCommitHash:         strings.Replace(gitHash, "'", "", -1),
 		NodeAddr:              nodeAddr,
-		NumConfs:              3,
+		NumConfs:              6,
 		FormFields:            make(map[string]string),
 		ActiveChannels:        activeChannels.Channels,
 		PendingChannels:       pendingChannels.PendingOpenChannels,
 		OpenChannelAction:     OpenChannelAction,
 		GenerateInvoiceAction: GenerateInvoiceAction,
+		PayInvoiceAction:      PayInvoiceAction,
 	}, nil
 }
 
@@ -501,15 +554,19 @@ func (l *lightningFaucet) faucetHome(w http.ResponseWriter, r *http.Request) {
 	// form to open a channel, so we'll pass that off to the openChannel
 	// handler.
 	case r.Method == http.MethodPost:
-		action := r.URL.Query()["action"]
-
-		// action == 0 is to open channel, action == 1 is to generate
-		if action[0] == OpenChannelAction {
-			l.openChannel(homeTemplate, homeInfo, w, r)
-		} else if action[0] == GenerateInvoiceAction {
-			l.generateInvoice(homeTemplate, homeInfo, w, r)
+		actions := r.URL.Query()["action"]
+		if len(actions) > 0 {
+			action := actions[0]
+			// action == 0 is to open channel, action == 1 is to generate, action == 2 is to pay
+			switch action {
+			case OpenChannelAction:
+				l.openChannel(homeTemplate, homeInfo, w, r)
+			case GenerateInvoiceAction:
+				l.generateInvoice(homeTemplate, homeInfo, w, r)
+			case PayInvoiceAction:
+				l.payInvoice(homeTemplate, homeInfo, w, r)
+			}
 		}
-
 	// If the method isn't either of those, then this is an error as we
 	// only support the two methods above.
 	default:
@@ -818,3 +875,95 @@ func (l *lightningFaucet) generateInvoice(homeTemplate *template.Template,
 		log.Errorf("unable to render home page: %v", err)
 	}
 }
+
+// payInvoice is a hybrid http.Handler that handles: the validation of the
+// pay invoice form, rendering errors to the form, and finally streaming the
+// payment if all the parameters check out.
+func (l *lightningFaucet) payInvoice(homeTemplate *template.Template,
+	homeState *homePageContext, w http.ResponseWriter, r *http.Request) {
+
+	elapsed := time.Since(lastPayInvoiceTime)
+	if elapsed < PayInvoiceTimeout {
+		homeState.SubmissionError = PayInvoiceTimeNotElapsed
+		homeTemplate.Execute(w, homeState)
+		return
+	}
+	lastPayInvoiceTime = time.Now()
+
+	// Get the invoice and try to verify and decode.
+	ctxb := context.Background()
+	rawPayReq := r.FormValue("payinvoice")
+	payReq := strings.TrimSpace(rawPayReq)
+	payReqString := &lnrpc.PayReqString{PayReq: payReq}
+	decodedPayReq, err := l.lnd.DecodePayReq(ctxb, payReqString)
+	if err != nil {
+		log.Errorf("Error on decode pay_req: %v", err)
+		homeState.SubmissionError = ErrorDecodingPayReq
+		homeTemplate.Execute(w, homeState)
+		return
+	}
+
+	decodedAmount := decodedPayReq.GetNumAtoms()
+
+	// Verify invoice amount.
+	if decodedAmount > maxPaymentAtoms {
+		log.Errorf("Max payout, pay_amount: %v", decodedAmount)
+		homeState.SubmissionError = ErrorPaymentAmount
+		homeTemplate.Execute(w, homeState)
+		return
+	}
+
+	// Create the payment request.
+	req := &lnrpc.SendRequest{
+		PaymentRequest:       payReq,
+		Amt:                  decodedAmount,
+		IgnoreMaxOutboundAmt: false,
+	}
+
+	// Create a payment stream to send your payment request.
+	paymentStream, err := l.lnd.SendPayment(ctxb)
+	if err != nil {
+		log.Errorf("Error on create Payment Stream: %v", err)
+		homeState.SubmissionError = PaymentStreamError
+		homeTemplate.Execute(w, homeState)
+		return
+	}
+
+	// Stream the payment request.
+	if err := paymentStream.Send(req); err != nil {
+		log.Errorf("Error on send pay_req: %v", err)
+		homeState.SubmissionError = PaymentStreamError
+		homeTemplate.Execute(w, homeState)
+		return
+	}
+
+	// Receive response from streamed payment request.
+	resp, err := paymentStream.Recv()
+	if err != nil {
+		log.Errorf("Error on receive pay_req response: %v", err)
+		homeState.SubmissionError = PaymentStreamError
+		homeTemplate.Execute(w, homeState)
+		return
+	}
+
+	paymentStream.CloseSend()
+
+	// Log response and send to homeState to create the html version.
+	log.Infof("Invoice has been paid destination=%v	description=%v amount=%v pay_hash:%v preimage=%v",
+		decodedPayReq.Destination, decodedPayReq.Description,
+		dcrutil.Amount(resp.PaymentRoute.TotalAmt), hex.EncodeToString(resp.PaymentHash),
+		hex.EncodeToString(resp.PaymentPreimage))
+
+	amount := dcrutil.Amount(resp.PaymentRoute.TotalAmt)
+
+	homeState.PaymentDestination = decodedPayReq.Destination
+	homeState.PaymentDescription = decodedPayReq.Description
+	homeState.PaymentAmount = amount.String()
+	homeState.PaymentHash = hex.EncodeToString(resp.PaymentHash)
+	homeState.PaymentPreimage = hex.EncodeToString(resp.PaymentPreimage)
+	homeState.PaymentHops = resp.PaymentRoute.Hops
+
+	if err := homeTemplate.Execute(w, homeState); err != nil {
+		log.Errorf("unable to render home page: %v", err)
+	}
+}
diff --git a/go.mod b/go.mod
@@ -1,4 +1,4 @@
-module github.com/decred/lightning-faucet/main
+module github.com/decred/lightning-faucet
 
 go 1.12
 

diff --git a/static/index.html b/static/index.html
@@ -135,7 +135,6 @@ <h4>Target confirmation count reached</h4>
 
   </div>
 </div>
-
 <div class="content mb-3 p-4">
   <h2>Generate Invoice</h2>
   <form id="generateInvoiceForm" method="post" action="/?action={{ .GenerateInvoiceAction }}">
@@ -184,6 +183,57 @@ <h4>Invoice successfully generated</h4>
   </form>
 </div>
 
+<div class="content mb-3 p-4">
+  <h2>Pay Invoice</h2>
+  <form id="payInvoiceForm" method="post" action="/?action={{ .PayInvoiceAction }}">
+      <div class="form-group">
+
+        <input class="form-control {{if eq .SubmissionError 12 14 15 16 }}is-invalid{{end}}"
+        id="payinvoice" name="payinvoice" type="text" required="true" placeholder="Invoce code">
+
+        {{ if eq .SubmissionError 12 14 15 16 }}
+          <div class="invalid-feedback">{{printf "%v" .SubmissionError}}</div>
+        {{end}}
+      </div>
+
+      {{ if .PaymentDestination }}
+        <div class="form-group" >
+          <h4>Invoice successfully paid</h4>
+          <div class="content p-4" style="word-break: break-all">
+            <p>Destination: {{ .PaymentDestination }}</p>
+            <p>Description: {{ .PaymentDescription }}</p>
+            <p>Amount: {{ .PaymentAmount }}</p>
+            <p>PayHash: {{ .PaymentHash }}</p>
+            <p>Preimage: {{ .PaymentPreimage }}</p>
+          </div><br />
+          <h4>Hops in channels:</h4>
+            {{range $i, $hop := .PaymentHops}}
+            <div class="channel d-inline-block p-2">
+                <span style="font-weight:bold;">Hop: </span>{{ $i }}<br />
+                <span style="font-weight:bold;">Remote PubKey: </span>{{ $hop.PubKey }}<br />
+                <span style="font-weight:bold;">ChanId: </span>{{ $hop.ChanId }}<br />
+                <span style="font-weight:bold;">Fee: </span>{{ $hop.FeeMAtoms }}<br />
+            </div>
+            {{end}}
+        </div>
+      {{ end }}
+
+      <div class="form-group row justify-content-center">
+        <button class="btn btn-outline-primary btn-outline-primary--inverted d-lg-inline-block d-block mb-3 px-4" type="submit">Pay Invoice</button>
+      </div>
+
+      <script>
+        (function() {
+          $("input").change(function() {
+            $(this).removeClass("is-invalid");
+          });
+        })();
+      </script>
+  </form>
+</div>
+
+
+
 {{if eq .ChannelTxid ""}}
   <div class="content mb-3 p-4">
     {{ if gt (len $.PendingChannels) 0 }}