Add noscrypt and reorganize namespaces

11 files changed, 319 insertions, 211 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 754b0f9..e8be787 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -8,7 +8,8 @@ include(FetchContent)
 # Specify the C++ standard
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
-SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -march=native")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -march=native")
+set(CMAKE_POSITION_INDEPENDENT_CODE ON)
 
 get_directory_property(HAS_PARENT PARENT_DIRECTORY)
 if(HAS_PARENT)
@@ -45,39 +46,50 @@ FetchContent_Declare(
     GIT_TAG v1.0.0
 )
 FetchContent_Populate(uuid_v4)
-set(uuid_v4_INCLUDE_DIR ${CMAKE_SOURCE_DIR}/_deps/uuid_v4-src/)
 
-find_path(uuid_v4_INCLUDE_DIR uuid_v4.h)
-include_directories(${uuid_v4_INCLUDE_DIR})
+FetchContent_GetProperties(uuid_v4)
+include_directories(${uuid_v4_SOURCE_DIR})
 
 #======== Configure noscrypt ========#
 FetchContent_Declare(
     libnoscrypt
     GIT_REPOSITORY git@github.com:VnUgE/noscrypt.git
-    GIT_TAG 872c49d1925b2576f85ec2587747119e895a675b
+    GIT_TAG d09d9330415d463ca19be9394b02ce11b3366f7e
 )
 FetchContent_MakeAvailable(libnoscrypt)
 
+FetchContent_GetProperties(libnoscrypt)
+include_directories(${libnoscrypt_SOURCE_DIR}/include)
+
 set_target_properties(noscrypt PROPERTIES CRYPTO_LIB openssl)
 
 #======== Build the project ========#
 set(INCLUDE_DIR ./include)
 set(CLIENT_INCLUDE_DIR ./include/client)
+set(DATA_INCLUDE_DIR ./include/data)
+set(SIGNER_INCLUDE_DIR ./include/signer)
 include_directories(${INCLUDE_DIR})
 include_directories(${CLIENT_INCLUDE_DIR})
+include_directories(${DATA_INCLUDE_DIR})
+include_directories(${SIGNER_INCLUDE_DIR})
 
 set(HEADERS
     ${INCLUDE_DIR}/nostr.hpp
     ${CLIENT_INCLUDE_DIR}/web_socket_client.hpp
+    ${DATA_INCLUDE_DIR}/data.hpp
+    ${SIGNER_INCLUDE_DIR}/signer.hpp
 )
 
 set(SOURCE_DIR ./src)
 set(CLIENT_SOURCE_DIR ./src/client)
+set(DATA_SOURCE_DIR ./src/data)
+set(SIGNER_SOURCE_DIR ./src/signer)
 set(SOURCES
-    ${SOURCE_DIR}/event.cpp
-    ${SOURCE_DIR}/filters.cpp
     ${SOURCE_DIR}/nostr_service.cpp
     ${CLIENT_SOURCE_DIR}/websocketpp_client.cpp
+    ${DATA_SOURCE_DIR}/event.cpp
+    ${DATA_SOURCE_DIR}/filters.cpp
+    ${SIGNER_SOURCE_DIR}/noscrypt_signer.cpp
 )
 
 add_library(aedile ${SOURCES} ${HEADERS})
@@ -87,6 +99,7 @@ target_link_libraries(aedile PRIVATE
     OpenSSL::Crypto
     plog::plog
     websocketpp::websocketpp
+    noscrypt
 )
 set_target_properties(aedile PROPERTIES WINDOWS_EXPORT_ALL_SYMBOLS YES)
 
@@ -111,12 +124,12 @@ set(TEST_SOURCES
 
 add_executable(aedile_test ${TEST_SOURCES} ${HEADERS})
 target_link_libraries(aedile_test PRIVATE
-    aedile
     GTest::gmock
     GTest::gtest
     GTest::gtest_main
     plog::plog
     websocketpp::websocketpp
+    aedile
 )
 set_target_properties(aedile_test PROPERTIES WINDOWS_EXPORT_ALL_SYMBOLS YES)
 
diff --git a/include/client/web_socket_client.hpp b/include/client/web_socket_client.hpp
index 63fa634..e186e90 100644
--- a/include/client/web_socket_client.hpp
+++ b/include/client/web_socket_client.hpp
@@ -6,6 +6,8 @@
 #include <websocketpp/client.hpp>
 #include <websocketpp/config/asio_client.hpp>
 
+namespace nostr
+{
 namespace client
 {
 /**
@@ -72,3 +74,4 @@ public:
     virtual void closeConnection(std::string uri) = 0;
 };
 } // namespace client
+} // namespace nostr
diff --git a/include/data/data.hpp b/include/data/data.hpp
new file mode 100644
index 0000000..46156cd
--- /dev/null
+++ b/include/data/data.hpp
@@ -0,0 +1,114 @@
+#pragma once
+
+#include <chrono>
+#include <string>
+#include <unordered_map>
+#include <vector>
+
+#include <nlohmann/json.hpp>
+#include <openssl/evp.h>
+#include <openssl/sha.h>
+
+namespace nostr
+{
+namespace data
+{
+/**
+ * @brief A Nostr event.
+ * @remark All data transmitted over the Nostr protocol is encoded in JSON blobs.  This struct
+ * is common to every Nostr event kind.  The significance of each event is determined by the
+ * `tags` and `content` fields.
+*/
+struct Event
+{
+    std::string id; ///< SHA-256 hash of the event data.
+    std::string pubkey; ///< Public key of the event creator.
+    std::time_t createdAt; ///< Unix timestamp of the event creation.
+    int kind; ///< Event kind.
+    std::vector<std::vector<std::string>> tags; ///< Arbitrary event metadata.
+    std::string content; ///< Event content.
+    std::string sig; ///< Event signature created with the private key of the event creator.
+
+    /**
+     * @brief Serializes the event to a JSON object.
+     * @returns A stringified JSON object representing the event.
+     * @throws `std::invalid_argument` if the event object is invalid.
+     */
+    std::string serialize();
+
+    /**
+     * @brief Deserializes the event from a JSON string.
+     * @param jsonString A stringified JSON object representing the event.
+     * @returns An event instance created from the JSON string.
+     */
+    static Event fromString(std::string jsonString);
+
+    /**
+     * @brief Deserializes the event from a JSON object.
+     * @param j A JSON object representing the event.
+     * @returns An event instance created from the JSON object.
+     */
+    static Event fromJson(nlohmann::json j);
+
+    /**
+     * @brief Compares two events for equality.
+     * @remark Two events are considered equal if they have the same ID, since the ID is uniquely
+     * generated from the event data.  If the `id` field is empty for either event, the comparison
+     * function will throw an exception.
+     */
+    bool operator==(const Event& other) const;
+
+private:
+    /**
+     * @brief Validates the event.
+     * @throws `std::invalid_argument` if the event object is invalid.
+     * @remark The `createdAt` field defaults to the present if it is not already set.
+     */
+    void validate();
+
+    /**
+     * @brief Generates an ID for the event.
+     * @param serializedData The serialized JSON string of all of the event data except the ID and
+     * the signature.
+     * @return A valid Nostr event ID.
+     * @remark The ID is a 32-bytes lowercase hex-encoded sha256 of the serialized event data.
+     */
+    std::string generateId(std::string serializedData) const;
+};
+
+/**
+ * @brief A set of filters for querying Nostr relays.
+ * @remark The `limit` field should always be included to keep the response size reasonable.  The
+ * `since` field is not required, and the `until` field will default to the present.  At least one
+ * of the other fields must be set for a valid filter.
+ */
+struct Filters
+{
+    std::vector<std::string> ids; ///< Event IDs.
+    std::vector<std::string> authors; ///< Event author npubs.
+    std::vector<int> kinds; ///< Kind numbers.
+    std::unordered_map<std::string, std::vector<std::string>> tags; ///< Tag names mapped to lists of tag values.
+    std::time_t since; ///< Unix timestamp.  Matching events must be newer than this.
+    std::time_t until; ///< Unix timestamp.  Matching events must be older than this.
+    int limit; ///< The maximum number of events the relay should return on the initial query.
+
+    /**
+     * @brief Serializes the filters to a JSON object.
+     * @param subscriptionId A string up to 64 chars in length that is unique per relay connection.
+     * @returns A stringified JSON object representing the filters.
+     * @throws `std::invalid_argument` if the filter object is invalid.
+     * @remarks The Nostr client is responsible for managing subscription IDs.  Responses from the
+     * relay will be organized by subscription ID.
+     */
+    std::string serialize(std::string& subscriptionId);
+
+private:
+    /**
+     * @brief Validates the filters.
+     * @throws `std::invalid_argument` if the filter object is invalid.
+     * @remark The `until` field defaults to the present if it is not already set.
+     */
+    void validate();
+};
+} // namespace data
+} // namespace nostr
diff --git a/include/nostr.hpp b/include/nostr.hpp
index e5b29c7..76bacd9 100644
--- a/include/nostr.hpp
+++ b/include/nostr.hpp
@@ -9,8 +9,6 @@
 #include <vector>
 
 #include <nlohmann/json.hpp>
-#include <openssl/evp.h>
-#include <openssl/sha.h>
 #include <plog/Init.h>
 #include <plog/Log.h>
 #include <websocketpp/client.hpp>
@@ -18,121 +16,24 @@
 #include <uuid_v4.h>
 
 #include "client/web_socket_client.hpp"
+#include "data/data.hpp"
+#include "signer/signer.hpp"
 
 namespace nostr
 {
-class ISigner;
 class NostrService;
 
-/**
- * @brief A Nostr event.
- * @remark All data transmitted over the Nostr protocol is encoded in JSON blobs.  This struct
- * is common to every Nostr event kind.  The significance of each event is determined by the
- * `tags` and `content` fields.
-*/
-struct Event
-{
-    std::string id; ///< SHA-256 hash of the event data.
-    std::string pubkey; ///< Public key of the event creator.
-    std::time_t createdAt; ///< Unix timestamp of the event creation.
-    int kind; ///< Event kind.
-    std::vector<std::vector<std::string>> tags; ///< Arbitrary event metadata.
-    std::string content; ///< Event content.
-    std::string sig; ///< Event signature created with the private key of the event creator.
-
-    /**
-     * @brief Serializes the event to a JSON object.
-     * @returns A stringified JSON object representing the event.
-     * @throws `std::invalid_argument` if the event object is invalid.
-     */
-    std::string serialize();
-
-    /**
-     * @brief Deserializes the event from a JSON string.
-     * @param jsonString A stringified JSON object representing the event.
-     * @returns An event instance created from the JSON string.
-     */
-    static Event fromString(std::string jsonString);
-
-    /**
-     * @brief Deserializes the event from a JSON object.
-     * @param j A JSON object representing the event.
-     * @returns An event instance created from the JSON object.
-     */
-    static Event fromJson(nlohmann::json j);
-
-    /**
-     * @brief Compares two events for equality.
-     * @remark Two events are considered equal if they have the same ID, since the ID is uniquely
-     * generated from the event data.  If the `id` field is empty for either event, the comparison
-     * function will throw an exception.
-     */
-    bool operator==(const Event& other) const;
-
-private:
-    /**
-     * @brief Validates the event.
-     * @throws `std::invalid_argument` if the event object is invalid.
-     * @remark The `createdAt` field defaults to the present if it is not already set.
-     */
-    void validate();
-
-    /**
-     * @brief Generates an ID for the event.
-     * @param serializedData The serialized JSON string of all of the event data except the ID and
-     * the signature.
-     * @return A valid Nostr event ID.
-     * @remark The ID is a 32-bytes lowercase hex-encoded sha256 of the serialized event data.
-     */
-    std::string generateId(std::string serializedData) const;
-};
-
-/**
- * @brief A set of filters for querying Nostr relays.
- * @remark The `limit` field should always be included to keep the response size reasonable.  The
- * `since` field is not required, and the `until` field will default to the present.  At least one
- * of the other fields must be set for a valid filter.
- */
-struct Filters
-{
-    std::vector<std::string> ids; ///< Event IDs.
-    std::vector<std::string> authors; ///< Event author npubs.
-    std::vector<int> kinds; ///< Kind numbers.
-    std::unordered_map<std::string, std::vector<std::string>> tags; ///< Tag names mapped to lists of tag values.
-    std::time_t since; ///< Unix timestamp.  Matching events must be newer than this.
-    std::time_t until; ///< Unix timestamp.  Matching events must be older than this.
-    int limit; ///< The maximum number of events the relay should return on the initial query.
-
-    /**
-     * @brief Serializes the filters to a JSON object.
-     * @param subscriptionId A string up to 64 chars in length that is unique per relay connection.
-     * @returns A stringified JSON object representing the filters.
-     * @throws `std::invalid_argument` if the filter object is invalid.
-     * @remarks The Nostr client is responsible for managing subscription IDs.  Responses from the
-     * relay will be organized by subscription ID.
-     */
-    std::string serialize(std::string& subscriptionId);
-
-private:
-    /**
-     * @brief Validates the filters.
-     * @throws `std::invalid_argument` if the filter object is invalid.
-     * @remark The `until` field defaults to the present if it is not already set.
-     */
-    void validate();
-};
-
 class NostrService
 {
 public:
     NostrService(
         std::shared_ptr<plog::IAppender> appender,
         std::shared_ptr<client::IWebSocketClient> client,
-        std::shared_ptr<ISigner> signer);
+        std::shared_ptr<signer::ISigner> signer);
     NostrService(
         std::shared_ptr<plog::IAppender> appender,
         std::shared_ptr<client::IWebSocketClient> client,
-        std::shared_ptr<ISigner> signer,
+        std::shared_ptr<signer::ISigner> signer,
         std::vector<std::string> relays);
     ~NostrService();
 
@@ -171,7 +72,7 @@ public:
      * to which relays the event was published successfully, and to which relays the event failed
      * to publish.
      */
-    std::tuple<std::vector<std::string>, std::vector<std::string>> publishEvent(std::shared_ptr<Event> event);
+    std::tuple<std::vector<std::string>, std::vector<std::string>> publishEvent(std::shared_ptr<data::Event> event);
 
     /**
      * @brief Queries all open relay connections for events matching the given set of filters, and
@@ -185,7 +86,7 @@ public:
      * set on the filters in the range 1-64, inclusive.  If no valid limit is given, it will be
      * defaulted to 16.
      */
-    std::vector<std::shared_ptr<Event>> queryRelays(std::shared_ptr<Filters> filters);
+    std::vector<std::shared_ptr<data::Event>> queryRelays(std::shared_ptr<data::Filters> filters);
 
     /**
      * @brief Queries all open relay connections for events matching the given set of filters.
@@ -202,8 +103,8 @@ public:
      * events, and they will not be accessible via `getNewEvents`.
      */
     std::string queryRelays(
-        std::shared_ptr<Filters> filters,
-        std::function<void(const std::string&, std::shared_ptr<Event>)> eventHandler,
+        std::shared_ptr<data::Filters> filters,
+        std::function<void(const std::string&, std::shared_ptr<data::Event>)> eventHandler,
         std::function<void(const std::string&)> eoseHandler,
         std::function<void(const std::string&, const std::string&)> closeHandler);
     
@@ -242,7 +143,7 @@ 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;
+    std::shared_ptr<signer::ISigner> _signer;
 
     ///< A mutex to protect the instance properties.
     std::mutex _propertyMutex;
@@ -324,7 +225,7 @@ private:
      */
     void onSubscriptionMessage(
         std::string message,
-        std::function<void(const std::string&, std::shared_ptr<Event>)> eventHandler,
+        std::function<void(const std::string&, std::shared_ptr<data::Event>)> eventHandler,
         std::function<void(const std::string&)> eoseHandler,
         std::function<void(const std::string&, const std::string&)> closeHandler);
     
@@ -336,15 +237,4 @@ private:
      */
     void onAcceptance(std::string message, std::function<void(const bool)> acceptanceHandler);
 };
-
-class ISigner
-{
-public:
-    /**
-     * @brief Signs the given Nostr event.
-     * @param event The event to sign.
-     * @remark The event's `sig` field will be updated in-place with the signature.
-    */
-    virtual void sign(std::shared_ptr<Event> event) = 0;
-};
 } // namespace nostr
diff --git a/include/signer/signer.hpp b/include/signer/signer.hpp
new file mode 100644
index 0000000..e68df93
--- /dev/null
+++ b/include/signer/signer.hpp
@@ -0,0 +1,31 @@
+#pragma once
+
+#include "data/data.hpp"
+
+namespace nostr
+{
+namespace signer
+{
+/**
+ * @brief An interface for Nostr event signing that implements NIP-46.
+ */
+class ISigner
+{
+public:
+    virtual void receiveConnection(std::string connectionToken) = 0;
+
+    virtual void initiateConnection(
+        std::string relay,
+        std::string name,
+        std::string url,
+        std::string description) = 0;
+
+    /**
+     * @brief Signs the given Nostr event.
+     * @param event The event to sign.
+     * @remark The event's `sig` field will be updated in-place with the signature.
+     */
+    virtual void sign(std::shared_ptr<nostr::data::Event> event) = 0;
+};
+} // namespace signer
+} // namespace nostr
diff --git a/src/client/websocketpp_client.cpp b/src/client/websocketpp_client.cpp
index baae054..9967d74 100644
--- a/src/client/websocketpp_client.cpp
+++ b/src/client/websocketpp_client.cpp
@@ -9,6 +9,8 @@ using std::string;
 using std::tuple;
 using std::unordered_map;
 
+namespace nostr
+{
 namespace client
 {
 /**
@@ -127,3 +129,4 @@ private:
     };
 };
 } // namespace client
+} // namespace nostr
diff --git a/src/event.cpp b/src/data/event.cpp
index 703efae..620ee3f 100644
--- a/src/event.cpp
+++ b/src/data/event.cpp
@@ -1,12 +1,12 @@
-#include <ctime>
-
-#include "nostr.hpp"
+#include "data/data.hpp"
 
 using namespace nlohmann;
 using namespace std;
 
 namespace nostr
 {
+namespace data
+{
 string Event::serialize()
 {
     try
@@ -123,4 +123,5 @@ bool Event::operator==(const Event& other) const
 
     return this->id == other.id;
 };
+} // namespace data
 } // namespace nostr
diff --git a/src/filters.cpp b/src/data/filters.cpp
index 40596eb..7e1c744 100644
--- a/src/filters.cpp
+++ b/src/data/filters.cpp
@@ -1,10 +1,12 @@
-#include "nostr.hpp"
+#include "data/data.hpp"
 
 using namespace nlohmann;
 using namespace std;
 
 namespace nostr
 {
+namespace data
+{
 string Filters::serialize(string& subscriptionId)
 {
     try
@@ -64,4 +66,5 @@ void Filters::validate()
         throw invalid_argument("Filters::validate: At least one filter must be set.");
     }
 };
+} // namespace data
 } // namespace nostr
diff --git a/src/nostr_service.cpp b/src/nostr_service.cpp
index 664243f..9f6b8ce 100644
--- a/src/nostr_service.cpp
+++ b/src/nostr_service.cpp
@@ -1,5 +1,4 @@
 #include "nostr.hpp"
-#include "client/web_socket_client.hpp"
 
 using namespace nlohmann;
 using namespace std;
@@ -9,13 +8,13 @@ namespace nostr
 NostrService::NostrService(
     shared_ptr<plog::IAppender> appender,
     shared_ptr<client::IWebSocketClient> client,
-    shared_ptr<ISigner> signer)
+    shared_ptr<signer::ISigner> signer)
 : NostrService(appender, client, signer, {}) { };
 
 NostrService::NostrService(
     shared_ptr<plog::IAppender> appender,
     shared_ptr<client::IWebSocketClient> client,
-    shared_ptr<ISigner> signer,
+    shared_ptr<signer::ISigner> signer,
     vector<string> relays)
 : _defaultRelays(relays), _client(client), _signer(signer)
 {
@@ -58,8 +57,8 @@ vector<string> NostrService::openRelayConnections(vector<string> relays)
         connectionThread.join();
     }
 
-    size_t targetCount = relays.size();
-    size_t activeCount = this->_activeRelays.size();
+    std::size_t targetCount = relays.size();
+    std::size_t activeCount = this->_activeRelays.size();
     PLOG_INFO << "Connected to " << activeCount << "/" << targetCount << " target relays.";
 
     // This property should only contain successful relays at this point.
@@ -102,7 +101,7 @@ void NostrService::closeRelayConnections(vector<string> relays)
 };
 
 // TODO: Make this method return a promise.
-tuple<vector<string>, vector<string>> NostrService::publishEvent(shared_ptr<Event> event)
+tuple<vector<string>, vector<string>> NostrService::publishEvent(shared_ptr<data::Event> event)
 {
     vector<string> successfulRelays;
     vector<string> failedRelays;
@@ -174,8 +173,8 @@ tuple<vector<string>, vector<string>> NostrService::publishEvent(shared_ptr<Even
         }
     }
 
-    size_t targetCount = targetRelays.size();
-    size_t successfulCount = successfulRelays.size();
+    std::size_t targetCount = targetRelays.size();
+    std::size_t successfulCount = successfulRelays.size();
     PLOG_INFO << "Published event to " << successfulCount << "/" << targetCount << " target relays.";
 
     return make_tuple(successfulRelays, failedRelays);
@@ -183,7 +182,7 @@ tuple<vector<string>, vector<string>> NostrService::publishEvent(shared_ptr<Even
 
 // TODO: Make this method return a promise.
 // TODO: Add a timeout to this method to prevent hanging while waiting for the relay.
-vector<shared_ptr<Event>> NostrService::queryRelays(shared_ptr<Filters> filters)
+vector<shared_ptr<data::Event>> NostrService::queryRelays(shared_ptr<data::Filters> filters)
 {
     if (filters->limit > 64 || filters->limit < 1)
     {
@@ -191,7 +190,7 @@ vector<shared_ptr<Event>> NostrService::queryRelays(shared_ptr<Filters> filters)
         filters->limit = 16;
     }
 
-    vector<shared_ptr<Event>> events;
+    vector<shared_ptr<data::Event>> events;
 
     string subscriptionId = this->generateSubscriptionId();
     string request;
@@ -229,7 +228,7 @@ vector<shared_ptr<Event>> NostrService::queryRelays(shared_ptr<Filters> filters)
             {
                 this->onSubscriptionMessage(
                     payload,
-                    [&events](const string&, shared_ptr<Event> event)
+                    [&events](const string&, shared_ptr<data::Event> event)
                     {
                         events.push_back(event);
                     },
@@ -278,8 +277,8 @@ vector<shared_ptr<Event>> NostrService::queryRelays(shared_ptr<Filters> filters)
 };
 
 string NostrService::queryRelays(
-    shared_ptr<Filters> filters,
-    function<void(const string&, shared_ptr<Event>)> eventHandler,
+    shared_ptr<data::Filters> filters,
+    function<void(const string&, shared_ptr<data::Event>)> eventHandler,
     function<void(const string&)> eoseHandler,
     function<void(const string&, const string&)> closeHandler)
 {
@@ -322,8 +321,8 @@ string NostrService::queryRelays(
         }
     }
 
-    size_t targetCount = this->_activeRelays.size();
-    size_t successfulCount = successfulRelays.size();
+    std::size_t targetCount = this->_activeRelays.size();
+    std::size_t successfulCount = successfulRelays.size();
     PLOG_INFO << "Sent query to " << successfulCount << "/" << targetCount << " open relay connections.";
 
     return subscriptionId;
@@ -335,7 +334,7 @@ tuple<vector<string>, vector<string>> NostrService::closeSubscription(string sub
     vector<string> failedRelays;
 
     vector<string> subscriptionRelays;
-    size_t subscriptionRelayCount;
+    std::size_t subscriptionRelayCount;
     vector<future<tuple<string, bool>>> closeFutures;
 
     try
@@ -375,7 +374,7 @@ tuple<vector<string>, vector<string>> NostrService::closeSubscription(string sub
         }
     }
 
-    size_t successfulCount = successfulRelays.size();
+    std::size_t successfulCount = successfulRelays.size();
     PLOG_INFO << "Sent CLOSE request for subscription " << subscriptionId << " to " << successfulCount << "/" << subscriptionRelayCount << " open relay connections.";
 
     // If there were no failures, and the subscription has been closed on all of its relays, forget
@@ -596,7 +595,7 @@ bool NostrService::hasSubscription(string subscriptionId, string relay)
 
 void NostrService::onSubscriptionMessage(
     string message,
-    function<void(const string&, shared_ptr<Event>)> eventHandler,
+    function<void(const string&, shared_ptr<data::Event>)> eventHandler,
     function<void(const string&)> eoseHandler,
     function<void(const string&, const string&)> closeHandler)
 {
@@ -607,8 +606,8 @@ void NostrService::onSubscriptionMessage(
         if (messageType == "EVENT")
         {
             string subscriptionId = jMessage.at(1);
-            Event event = Event::fromString(jMessage.at(2));
-            eventHandler(subscriptionId, make_shared<Event>(event));
+            data::Event event = data::Event::fromString(jMessage.at(2));
+            eventHandler(subscriptionId, make_shared<data::Event>(event));
         }
         else if (messageType == "EOSE")
         {
diff --git a/src/signer/noscrypt_signer.cpp b/src/signer/noscrypt_signer.cpp
new file mode 100644
index 0000000..a798271
--- /dev/null
+++ b/src/signer/noscrypt_signer.cpp
@@ -0,0 +1,34 @@
+#include <noscrypt.h>
+
+#include "signer.hpp"
+
+using namespace std;
+
+namespace nostr
+{
+namespace signer
+{
+class NoscryptSigner : public ISigner
+{
+public:
+    void receiveConnection(string connectionToken) override
+    {
+        // Receive the connection token here.
+    };
+
+    void initiateConnection(
+        string relay,
+        string name,
+        string url,
+        string description) override
+    {
+        // Initiate the connection here.
+    };
+
+    void sign(shared_ptr<data::Event> event) override
+    {
+        // Sign the event here.
+    };
+};
+} // namespace signer
+} // namespace nostr
diff --git a/test/nostr_service_test.cpp b/test/nostr_service_test.cpp
index b3b9b28..3e951ad 100644
--- a/test/nostr_service_test.cpp
+++ b/test/nostr_service_test.cpp
@@ -1,15 +1,18 @@
 #include <chrono>
+#include <iostream>
+
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
 #include <nlohmann/json.hpp>
 #include <plog/Appenders/ConsoleAppender.h>
 #include <plog/Formatters/TxtFormatter.h>
-#include <iostream>
 #include <websocketpp/client.hpp>
 
-#include <client/web_socket_client.hpp>
-#include <nostr.hpp>
+#include "nostr.hpp"
+#include "client/web_socket_client.hpp"
+#include "signer/signer.hpp"
 
+using namespace nostr;
 using namespace std;
 using namespace ::testing;
 
@@ -29,13 +32,27 @@ public:
     MOCK_METHOD(void, closeConnection, (string uri), (override));
 };
 
-class FakeSigner : public nostr::ISigner 
+class FakeSigner : public signer::ISigner 
 {
 public:
-    void sign(shared_ptr<nostr::Event> event) override
+    void receiveConnection(string connectionToken) override
+    {
+        // Do nothing.
+    };
+
+    void initiateConnection(
+        string relay,
+        string name,
+        string url,
+        string description) override
+    {
+        // Do nothing.
+    };
+
+    void sign(shared_ptr<nostr::data::Event> event) override
     {
         event->sig = "fake_signature";
-    }
+    };
 };
 
 class NostrServiceTest : public testing::Test
@@ -47,9 +64,9 @@ public:
         "wss://nostr.thesamecat.io"
     };
 
-    static const nostr::Event getTextNoteTestEvent()
+    static const nostr::data::Event getTextNoteTestEvent()
     {
-        nostr::Event event;
+        nostr::data::Event event;
         event.pubkey = "13tn5ccv2guflxgffq4aj0hw5x39pz70zcdrfd6vym887gry38zys28dask";
         event.kind = 1;
         event.tags =
@@ -63,12 +80,12 @@ public:
         return event;
     };
 
-    static const vector<nostr::Event> getMultipleTextNoteTestEvents()
+    static const vector<nostr::data::Event> getMultipleTextNoteTestEvents()
     {
         auto now = std::chrono::system_clock::now();
         std::time_t currentTime = std::chrono::system_clock::to_time_t(now);
 
-        nostr::Event event1;
+        nostr::data::Event event1;
         event1.pubkey = "13tn5ccv2guflxgffq4aj0hw5x39pz70zcdrfd6vym887gry38zys28dask";
         event1.kind = 1;
         event1.tags = 
@@ -80,7 +97,7 @@ public:
         event1.content = "Hello, World!";
         event1.createdAt = currentTime;
 
-        nostr::Event event2;
+        nostr::data::Event event2;
         event2.pubkey = "1l9d9jh67rkwayalrxcy686aujyz5pper5kzjv8jvg8pu9v9ns4ls0xvq42";
         event2.kind = 1;
         event2.tags =
@@ -92,7 +109,7 @@ public:
         event2.content = "Welcome to Nostr!";
         event2.createdAt = currentTime;
         
-        nostr::Event event3;
+        nostr::data::Event event3;
         event3.pubkey = "187ujhtmnv82ftg03h4heetwk3dd9mlfkf8th3fvmrk20nxk9mansuzuyla";
         event3.kind = 1;
         event3.tags =
@@ -107,9 +124,9 @@ public:
         return { event1, event2, event3 };
     };
 
-    static const nostr::Event getLongFormTestEvent()
+    static const nostr::data::Event getLongFormTestEvent()
     {
-        nostr::Event event;
+        nostr::data::Event event;
         event.pubkey = "13tn5ccv2guflxgffq4aj0hw5x39pz70zcdrfd6vym887gry38zys28dask";
         event.kind = 30023;
         event.tags =
@@ -123,7 +140,7 @@ public:
         return event;
     }
 
-    static const string getTestEventMessage(shared_ptr<nostr::Event> event, string subscriptionId)
+    static const string getTestEventMessage(shared_ptr<nostr::data::Event> event, string subscriptionId)
     {        
         auto signer = make_unique<FakeSigner>();
         signer->sign(event);
@@ -136,9 +153,9 @@ public:
         return jarr.dump();
     }
 
-    static const nostr::Filters getKind0And1TestFilters()
+    static const nostr::data::Filters getKind0And1TestFilters()
     {
-        nostr::Filters filters;
+        nostr::data::Filters filters;
         filters.authors = {
             "13tn5ccv2guflxgffq4aj0hw5x39pz70zcdrfd6vym887gry38zys28dask", 
             "1l9d9jh67rkwayalrxcy686aujyz5pper5kzjv8jvg8pu9v9ns4ls0xvq42",
@@ -150,9 +167,9 @@ public:
         return filters;
     }
 
-    static const nostr::Filters getKind30023TestFilters()
+    static const nostr::data::Filters getKind30023TestFilters()
     {
-        nostr::Filters filters;
+        nostr::data::Filters filters;
         filters.authors = {
             "13tn5ccv2guflxgffq4aj0hw5x39pz70zcdrfd6vym887gry38zys28dask", 
             "1l9d9jh67rkwayalrxcy686aujyz5pper5kzjv8jvg8pu9v9ns4ls0xvq42",
@@ -461,7 +478,7 @@ TEST_F(NostrServiceTest, PublishEvent_CorrectlyIndicates_AllSuccesses)
         .WillRepeatedly(Invoke([](string message, string uri, function<void(const string&)> messageHandler)
         {
             json messageArr = json::parse(message);
-            auto event = nostr::Event::fromString(messageArr[1]);
+            auto event = nostr::data::Event::fromString(messageArr[1]);
 
             json jarr = json::array({ "OK", event.id, true, "Event accepted" });
             messageHandler(jarr.dump());
@@ -469,7 +486,7 @@ TEST_F(NostrServiceTest, PublishEvent_CorrectlyIndicates_AllSuccesses)
             return make_tuple(uri, true);
         }));
     
-    auto testEvent = make_shared<nostr::Event>(getTextNoteTestEvent());
+    auto testEvent = make_shared<nostr::data::Event>(getTextNoteTestEvent());
     auto [successes, failures] = nostrService->publishEvent(testEvent);
 
     ASSERT_EQ(successes.size(), defaultTestRelays.size());
@@ -515,7 +532,7 @@ TEST_F(NostrServiceTest, PublishEvent_CorrectlyIndicates_AllFailures)
             return make_tuple(uri, false);
         }));
     
-    auto testEvent = make_shared<nostr::Event>(getTextNoteTestEvent());
+    auto testEvent = make_shared<nostr::data::Event>(getTextNoteTestEvent());
     auto [successes, failures] = nostrService->publishEvent(testEvent);
 
     ASSERT_EQ(successes.size(), 0);
@@ -566,7 +583,7 @@ TEST_F(NostrServiceTest, PublishEvent_CorrectlyIndicates_MixedSuccessesAndFailur
         .WillRepeatedly(Invoke([](string message, string uri, function<void(const string&)> messageHandler)
         {
             json messageArr = json::parse(message);
-            auto event = nostr::Event::fromString(messageArr[1]);
+            auto event = nostr::data::Event::fromString(messageArr[1]);
 
             json jarr = json::array({ "OK", event.id, true, "Event accepted" });
             messageHandler(jarr.dump());
@@ -574,7 +591,7 @@ TEST_F(NostrServiceTest, PublishEvent_CorrectlyIndicates_MixedSuccessesAndFailur
             return make_tuple(uri, true);
         }));
     
-    auto testEvent = make_shared<nostr::Event>(getTextNoteTestEvent());
+    auto testEvent = make_shared<nostr::data::Event>(getTextNoteTestEvent());
     auto [successes, failures] = nostrService->publishEvent(testEvent);
 
     ASSERT_EQ(successes.size(), 1);
@@ -616,7 +633,7 @@ TEST_F(NostrServiceTest, PublishEvent_CorrectlyIndicates_RejectedEvent)
         .WillRepeatedly(Invoke([](string message, string uri, function<void(const string&)> messageHandler)
         {
             json messageArr = json::parse(message);
-            auto event = nostr::Event::fromString(messageArr[1]);
+            auto event = nostr::data::Event::fromString(messageArr[1]);
 
             json jarr = json::array({ "OK", event.id, false, "Event rejected" });
             messageHandler(jarr.dump());
@@ -624,7 +641,7 @@ TEST_F(NostrServiceTest, PublishEvent_CorrectlyIndicates_RejectedEvent)
             return make_tuple(uri, true);
         }));
     
-    auto testEvent = make_shared<nostr::Event>(getTextNoteTestEvent());
+    auto testEvent = make_shared<nostr::data::Event>(getTextNoteTestEvent());
     auto [successes, failures] = nostrService->publishEvent(testEvent);
 
     ASSERT_EQ(failures.size(), defaultTestRelays.size());
@@ -667,7 +684,7 @@ TEST_F(NostrServiceTest, PublishEvent_CorrectlyIndicates_EventRejectedBySomeRela
         .WillRepeatedly(Invoke([](string message, string uri, function<void(const string&)> messageHandler)
         {
             json messageArr = json::parse(message);
-            auto event = nostr::Event::fromString(messageArr[1]);
+            auto event = nostr::data::Event::fromString(messageArr[1]);
 
             json jarr = json::array({ "OK", event.id, true, "Event accepted" });
             messageHandler(jarr.dump());
@@ -679,7 +696,7 @@ TEST_F(NostrServiceTest, PublishEvent_CorrectlyIndicates_EventRejectedBySomeRela
         .WillRepeatedly(Invoke([](string message, string uri, function<void(const string&)> messageHandler)
         {
             json messageArr = json::parse(message);
-            auto event = nostr::Event::fromString(messageArr[1]);
+            auto event = nostr::data::Event::fromString(messageArr[1]);
 
             json jarr = json::array({ "OK", event.id, false, "Event rejected" });
             messageHandler(jarr.dump());
@@ -687,7 +704,7 @@ TEST_F(NostrServiceTest, PublishEvent_CorrectlyIndicates_EventRejectedBySomeRela
             return make_tuple(uri, true);
         }));
     
-    auto testEvent = make_shared<nostr::Event>(getTextNoteTestEvent());
+    auto testEvent = make_shared<nostr::data::Event>(getTextNoteTestEvent());
     auto [successes, failures] = nostrService->publishEvent(testEvent);
 
     ASSERT_EQ(successes.size(), 1);
@@ -725,16 +742,16 @@ TEST_F(NostrServiceTest, QueryRelays_ReturnsEvents_UpToEOSE)
     nostrService->openRelayConnections();
 
     auto testEvents = getMultipleTextNoteTestEvents();
-    vector<shared_ptr<nostr::Event>> signedTestEvents;
-    for (nostr::Event testEvent : testEvents)
+    vector<shared_ptr<nostr::data::Event>> signedTestEvents;
+    for (nostr::data::Event testEvent : testEvents)
     {
-        auto signedEvent = make_shared<nostr::Event>(testEvent);
+        auto signedEvent = make_shared<nostr::data::Event>(testEvent);
         signer->sign(signedEvent);
 
         auto serializedEvent = signedEvent->serialize();
-        auto deserializedEvent = nostr::Event::fromString(serializedEvent);
+        auto deserializedEvent = nostr::data::Event::fromString(serializedEvent);
 
-        signedEvent = make_shared<nostr::Event>(deserializedEvent);
+        signedEvent = make_shared<nostr::data::Event>(deserializedEvent);
         signedTestEvents.push_back(signedEvent);
     }
 
@@ -751,7 +768,7 @@ TEST_F(NostrServiceTest, QueryRelays_ReturnsEvents_UpToEOSE)
 
             for (auto event : testEvents)
             {
-                auto sendableEvent = make_shared<nostr::Event>(event);
+                auto sendableEvent = make_shared<nostr::data::Event>(event);
                 signer->sign(sendableEvent);
                 json jarr = json::array({ "EVENT", subscriptionId, sendableEvent->serialize() });
                 messageHandler(jarr.dump());
@@ -770,7 +787,7 @@ TEST_F(NostrServiceTest, QueryRelays_ReturnsEvents_UpToEOSE)
             return make_tuple(uri, true);
         }));
 
-    auto filters = make_shared<nostr::Filters>(getKind0And1TestFilters());
+    auto filters = make_shared<nostr::data::Filters>(getKind0And1TestFilters());
     auto results = nostrService->queryRelays(filters);
 
     // TODO: Check results size when the queryRelays method deduplicates results before returning.
@@ -783,7 +800,7 @@ TEST_F(NostrServiceTest, QueryRelays_ReturnsEvents_UpToEOSE)
             find_if(
                 signedTestEvents.begin(),
                 signedTestEvents.end(),
-                [&resultEvent](shared_ptr<nostr::Event> testEvent)
+                [&resultEvent](shared_ptr<nostr::data::Event> testEvent)
                 {
                     return *testEvent == *resultEvent;
                 }),
@@ -822,16 +839,16 @@ TEST_F(NostrServiceTest, QueryRelays_CallsHandler_WithReturnedEvents)
     nostrService->openRelayConnections();
 
     auto testEvents = getMultipleTextNoteTestEvents();
-    vector<shared_ptr<nostr::Event>> signedTestEvents;
-    for (nostr::Event testEvent : testEvents)
+    vector<shared_ptr<nostr::data::Event>> signedTestEvents;
+    for (nostr::data::Event testEvent : testEvents)
     {
-        auto signedEvent = make_shared<nostr::Event>(testEvent);
+        auto signedEvent = make_shared<nostr::data::Event>(testEvent);
         signer->sign(signedEvent);
 
         auto serializedEvent = signedEvent->serialize();
-        auto deserializedEvent = nostr::Event::fromString(serializedEvent);
+        auto deserializedEvent = nostr::data::Event::fromString(serializedEvent);
 
-        signedEvent = make_shared<nostr::Event>(deserializedEvent);
+        signedEvent = make_shared<nostr::data::Event>(deserializedEvent);
         signedTestEvents.push_back(signedEvent);
     }
 
@@ -847,7 +864,7 @@ TEST_F(NostrServiceTest, QueryRelays_CallsHandler_WithReturnedEvents)
 
             for (auto event : testEvents)
             {
-                auto sendableEvent = make_shared<nostr::Event>(event);
+                auto sendableEvent = make_shared<nostr::data::Event>(event);
                 signer->sign(sendableEvent);
                 json jarr = json::array({ "EVENT", subscriptionId, sendableEvent->serialize() });
                 messageHandler(jarr.dump());
@@ -859,21 +876,21 @@ TEST_F(NostrServiceTest, QueryRelays_CallsHandler_WithReturnedEvents)
             return make_tuple(uri, true);
         }));
 
-    auto filters = make_shared<nostr::Filters>(getKind0And1TestFilters());
+    auto filters = make_shared<nostr::data::Filters>(getKind0And1TestFilters());
     promise<void> eoseReceivedPromise;
     auto eoseReceivedFuture = eoseReceivedPromise.get_future();
     int eoseCount = 0;
 
     string generatedSubscriptionId = nostrService->queryRelays(
         filters,
-        [&generatedSubscriptionId, &signedTestEvents](const string& subscriptionId, shared_ptr<nostr::Event> event)
+        [&generatedSubscriptionId, &signedTestEvents](const string& subscriptionId, shared_ptr<nostr::data::Event> event)
         {
             ASSERT_STREQ(subscriptionId.c_str(), generatedSubscriptionId.c_str());
             ASSERT_NE(
                 find_if(
                     signedTestEvents.begin(),
                     signedTestEvents.end(),
-                    [&event](shared_ptr<nostr::Event> testEvent)
+                    [&event](shared_ptr<nostr::data::Event> testEvent)
                     {
                         return *testEvent == *event;
                     }),
@@ -944,16 +961,16 @@ TEST_F(NostrServiceTest, Service_MaintainsMultipleSubscriptions_ThenClosesAll)
 
     // Mock relay responses.
     auto testEvents = getMultipleTextNoteTestEvents();
-    vector<shared_ptr<nostr::Event>> signedTestEvents;
-    for (nostr::Event testEvent : testEvents)
+    vector<shared_ptr<nostr::data::Event>> signedTestEvents;
+    for (nostr::data::Event testEvent : testEvents)
     {
-        auto signedEvent = make_shared<nostr::Event>(testEvent);
+        auto signedEvent = make_shared<nostr::data::Event>(testEvent);
         signer->sign(signedEvent);
 
         auto serializedEvent = signedEvent->serialize();
-        auto deserializedEvent = nostr::Event::fromString(serializedEvent);
+        auto deserializedEvent = nostr::data::Event::fromString(serializedEvent);
 
-        signedEvent = make_shared<nostr::Event>(deserializedEvent);
+        signedEvent = make_shared<nostr::data::Event>(deserializedEvent);
         signedTestEvents.push_back(signedEvent);
     }
 
@@ -970,7 +987,7 @@ TEST_F(NostrServiceTest, Service_MaintainsMultipleSubscriptions_ThenClosesAll)
 
             for (auto event : testEvents)
             {
-                auto sendableEvent = make_shared<nostr::Event>(event);
+                auto sendableEvent = make_shared<nostr::data::Event>(event);
                 signer->sign(sendableEvent);
                 json jarr = json::array({ "EVENT", subscriptionIds.at(0), sendableEvent->serialize() });
                 messageHandler(jarr.dump());
@@ -991,7 +1008,7 @@ TEST_F(NostrServiceTest, Service_MaintainsMultipleSubscriptions_ThenClosesAll)
 
             for (auto event : testEvents)
             {
-                auto sendableEvent = make_shared<nostr::Event>(event);
+                auto sendableEvent = make_shared<nostr::data::Event>(event);
                 signer->sign(sendableEvent);
                 json jarr = json::array({ "EVENT", subscriptionIds.at(1), sendableEvent->serialize() });
                 messageHandler(jarr.dump());
@@ -1004,8 +1021,8 @@ TEST_F(NostrServiceTest, Service_MaintainsMultipleSubscriptions_ThenClosesAll)
         }));
 
     // Send queries.
-    auto shortFormFilters = make_shared<nostr::Filters>(getKind0And1TestFilters());
-    auto longFormFilters = make_shared<nostr::Filters>(getKind30023TestFilters());
+    auto shortFormFilters = make_shared<nostr::data::Filters>(getKind0And1TestFilters());
+    auto longFormFilters = make_shared<nostr::data::Filters>(getKind30023TestFilters());
     promise<void> shortFormPromise;
     promise<void> longFormPromise;
     auto shortFormFuture = shortFormPromise.get_future();
@@ -1013,14 +1030,14 @@ TEST_F(NostrServiceTest, Service_MaintainsMultipleSubscriptions_ThenClosesAll)
 
     string shortFormSubscriptionId = nostrService->queryRelays(
         shortFormFilters,
-        [&shortFormSubscriptionId, &signedTestEvents](const string& subscriptionId, shared_ptr<nostr::Event> event)
+        [&shortFormSubscriptionId, &signedTestEvents](const string& subscriptionId, shared_ptr<nostr::data::Event> event)
         {
             ASSERT_STREQ(subscriptionId.c_str(), shortFormSubscriptionId.c_str());
             ASSERT_NE(
                 find_if(
                     signedTestEvents.begin(),
                     signedTestEvents.end(),
-                    [&event](shared_ptr<nostr::Event> testEvent)
+                    [&event](shared_ptr<nostr::data::Event> testEvent)
                     {
                         return *testEvent == *event;
                     }),
@@ -1035,14 +1052,14 @@ TEST_F(NostrServiceTest, Service_MaintainsMultipleSubscriptions_ThenClosesAll)
         [](const string&, const string&) {});
     string longFormSubscriptionId = nostrService->queryRelays(
         shortFormFilters,
-        [&longFormSubscriptionId, &signedTestEvents](const string& subscriptionId, shared_ptr<nostr::Event> event)
+        [&longFormSubscriptionId, &signedTestEvents](const string& subscriptionId, shared_ptr<nostr::data::Event> event)
         {
             ASSERT_STREQ(subscriptionId.c_str(), longFormSubscriptionId.c_str());
             ASSERT_NE(
                 find_if(
                     signedTestEvents.begin(),
                     signedTestEvents.end(),
-                    [&event](shared_ptr<nostr::Event> testEvent)
+                    [&event](shared_ptr<nostr::data::Event> testEvent)
                     {
                         return *testEvent == *event;
                     }),