From 6dde23e6c66e846c64d49c5258f0dbf44e3d0374 Mon Sep 17 00:00:00 2001
From: Michael Jurkoic <mjjurkoic@gmail.com>
Date: Mon, 18 Mar 2024 21:28:19 -0500
Subject: Declare a signer interface

---
 include/nostr.hpp     | 16 ++++++++++++++--
 src/event.cpp         |  6 +++---
 src/nostr_service.cpp |  2 +-
 3 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/include/nostr.hpp b/include/nostr.hpp
index 645090a..3e60d7b 100644
--- a/include/nostr.hpp
+++ b/include/nostr.hpp
@@ -18,7 +18,9 @@ namespace nostr
 typedef std::vector<std::string> RelayList;
 typedef std::unordered_map<std::string, std::vector<std::string>> TagMap;
 
-// TODO: Add null checking to seralization and deserialization methods.
+class ISigner;
+class NostrService;
+
 /**
  * @brief A Nostr event.
  * @remark All data transmitted over the Nostr protocol is encoded in JSON blobs.  This struct
@@ -40,7 +42,7 @@ struct Event
      * @returns A stringified JSON object representing the event.
      * @throws `std::invalid_argument` if the event object is invalid.
      */
-    std::string serialize();
+    std::string serialize(std::shared_ptr<ISigner> signer);
 
     /**
      * @brief Deserializes the event from a JSON string.
@@ -103,6 +105,7 @@ private:
 
 class NostrService
 {
+// TODO: Setup signer in the constructor.
 public:
     NostrService(
         std::shared_ptr<plog::IAppender> appender,
@@ -213,6 +216,9 @@ private:
 
     ///< The WebSocket client used to communicate with relays.
     std::shared_ptr<client::IWebSocketClient> _client;
+    ///< The signer used to sign Nostr events.
+    std::shared_ptr<ISigner> _signer;
+
     ///< A mutex to protect the instance properties.
     std::mutex _propertyMutex;
     ///< The default set of Nostr relays to which the service will attempt to connect.
@@ -287,4 +293,10 @@ private:
      */
     void onEvent(std::string subscriptionId, Event event);
 };
+
+class ISigner
+{
+public:
+    virtual std::string generateSignature(std::shared_ptr<Event> event) = 0;
+};
 } // namespace nostr
diff --git a/src/event.cpp b/src/event.cpp
index 4ba87d2..a24a594 100644
--- a/src/event.cpp
+++ b/src/event.cpp
@@ -13,13 +13,14 @@ using std::hex;
 using std::invalid_argument;
 using std::setw;
 using std::setfill;
+using std::shared_ptr;
 using std::string;
 using std::stringstream;
 using std::time;
 
 namespace nostr 
 {
-string Event::serialize()
+string Event::serialize(shared_ptr<ISigner> signer)
 {
     try
     {
@@ -40,8 +41,7 @@ string Event::serialize()
     };
 
     j["id"] = this->generateId(j.dump());
-
-    // TODO: Reach out to a signer to sign the event, then set the signature.
+    j["sig"] = signer->generateSignature(shared_ptr<Event>(this));
 
     json jarr = json::array({ "EVENT", j });
 
diff --git a/src/nostr_service.cpp b/src/nostr_service.cpp
index 0409a0d..7efc11e 100644
--- a/src/nostr_service.cpp
+++ b/src/nostr_service.cpp
@@ -129,7 +129,7 @@ tuple<RelayList, RelayList> NostrService::publishEvent(Event event)
     for (const string& relay : this->_activeRelays)
     {
         future<tuple<string, bool>> publishFuture = async([this, &relay, &event]() {
-            return this->_client->send(event.serialize(), relay);
+            return this->_client->send(event.serialize(this->_signer), relay);
         });
 
         publishFutures.push_back(move(publishFuture));
-- 
cgit