From 0133484711b2c6eb088576cdc58e8ec22c5eed60 Mon Sep 17 00:00:00 2001
From: Peter Sanchez <peter@netlandish.com>
Date: Mon, 12 Dec 2022 16:16:48 -0600
Subject: [PATCH] Adding (un)subscribe confirmation

---
 feedback.go | 36 ++++++++++++++++++++++++++----------
 1 file changed, 26 insertions(+), 10 deletions(-)

diff --git a/feedback.go b/feedback.go
index 4492e17..fdf238b 100644
--- a/feedback.go
+++ b/feedback.go
@@ -9,6 +9,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"io/ioutil"
 	"net/http"
 	"net/url"
 	"reflect"
@@ -68,7 +69,7 @@ type Record struct {
 	UnsubscribeURL   string `json:"UnsubscribeURL"`
 }
 
-func (r Record) getBytesToSign() []byte {
+func (r *Record) getBytesToSign() []byte {
 	var fields []string
 	var lines bytes.Buffer
 	if r.Type == "Notification" {
@@ -91,14 +92,14 @@ func (r Record) getBytesToSign() []byte {
 	return lines.Bytes()
 }
 
-func (r Record) signatureAlgorithm() x509.SignatureAlgorithm {
+func (r *Record) signatureAlgorithm() x509.SignatureAlgorithm {
 	if r.SignatureVersion == "2" {
 		return x509.SHA256WithRSA
 	}
 	return x509.SHA1WithRSA
 }
 
-func (r Record) verify() error {
+func (r *Record) verify() error {
 	// Get signature
 	signature, err := base64.StdEncoding.DecodeString(r.Signature)
 	if err != nil {
@@ -147,7 +148,7 @@ func (r Record) verify() error {
 func (s *Service) Feedback(c echo.Context) error {
 	gctx := c.(*server.Context)
 	req := c.Request()
-	var data Record
+	var data *Record
 	err := json.NewDecoder(req.Body).Decode(&data)
 	if err != nil {
 		return c.JSON(http.StatusOK, err)
@@ -165,7 +166,10 @@ func (s *Service) Feedback(c echo.Context) error {
 	case "Notification":
 		// For Notification, the Message field is a json-like string
 		var message map[string]any
-		json.Unmarshal([]byte(data.Message), &message)
+		err = json.Unmarshal([]byte(data.Message), &message)
+		if err != nil {
+			return err
+		}
 
 		// According to some settings `eventType` might be called `notificationType`
 		// https://docs.aws.amazon.com/ses/latest/dg/event-publishing-retrieving-sns-contents.html#event-publishing-retrieving-sns-contents-subscription-object
@@ -193,11 +197,23 @@ func (s *Service) Feedback(c echo.Context) error {
 		}
 		gctx.Server.Logger().Printf("Received %s notification", eventType)
 
-	case "SubscriptionConfirmation":
-		err = s.actions.Subscribe(data.Message)
-		gctx.Server.Logger().Printf("Received %s notification", data.Type)
-	case "UnsubscribeConfirmation":
-		err = s.actions.Unsubscribe(data.Message)
+	case "SubscriptionConfirmation", "UnsubscribeConfirmation":
+		resp, err := http.Get(data.SubscribeURL)
+		if err != nil {
+			return err
+		}
+		defer resp.Body.Close()
+
+		_, err = ioutil.ReadAll(resp.Body)
+		if err != nil {
+			return err
+		}
+
+		if data.Type == "SubscribeConfirmation" {
+			err = s.actions.Subscribe(data.Message)
+		} else {
+			err = s.actions.Unsubscribe(data.Message)
+		}
 		gctx.Server.Logger().Printf("Received %s notification", data.Type)
 	default:
 		gctx.Server.Logger().Printf("Error: Received unknown notification type: %s.", data.Type)
-- 
2.45.2