Adopt/prepared packet v0

CMakeLists.txt

@@ -383,6 +383,7 @@ if(AE_BUILD_EXAMPLES)
   add_subdirectory(examples/common)
   add_subdirectory(examples/cloud)
   add_subdirectory(examples/a_b_message_exchange)
+  add_subdirectory(examples/message_server)
   add_subdirectory(examples/capi/oddity)
   add_subdirectory(examples/benches/send_message_delays)
   add_subdirectory(examples/benches/send_messages_bandwidth)

aether/CMakeLists.txt

@@ -198,6 +198,8 @@ list(APPEND aether_srcs
 
 list(APPEND aether_srcs
             "server_connections/client_server_connection.cpp"
+            "prepared_packet/prepared_send_message.cpp"
+            "prepared_packet/packet_encoder.cpp"
             "server_connections/channel_select_action.cpp"
             "server_connections/server_connection.cpp")
 

aether/all.h

@@ -22,6 +22,7 @@
 #include "aether/aether_app.h"
 #include "aether/common.h"
 #include "aether/config.h"
+#include "aether/env.h"
 #include "aether/memory.h"
 
 #include "aether/actions/action_context.h"
@@ -94,6 +95,9 @@
 #include "aether/modems/imodem_driver.h"
 #include "aether/modems/modem_factory.h"
 
+#include "aether/prepared_packet/packet_encoder.h"
+#include "aether/prepared_packet/prepared_send_message.h"
+
 #include "aether/aether.h"
 #include "aether/channels/channel.h"
 #include "aether/client.h"

aether/channels/channel.h

@@ -17,12 +17,15 @@
 #ifndef AETHER_CHANNELS_CHANNEL_H_
 #define AETHER_CHANNELS_CHANNEL_H_
 
+#include <optional>
+
+#include "aether/channels/channel_statistics.h"
+#include "aether/channels/channels_types.h"
+#include "aether/executors/executors.h"
 #include "aether/memory.h"
 #include "aether/obj/obj.h"
-#include "aether/executors/executors.h"
 #include "aether/stream_api/istream.h"
-#include "aether/channels/channels_types.h"
-#include "aether/channels/channel_statistics.h"
+#include "aether/types/address.h"
 
 namespace ae {
 using TransportBuildSender =
@@ -44,6 +47,7 @@ class Channel : public Obj {
    */
   virtual TransportBuildSender TransportBuilder() = 0;
 
+  virtual std::optional<Endpoint> endpoint() const = 0;
   ChannelTransportProperties const& transport_properties() const;
   ChannelStatistics& channel_statistics();
 

aether/channels/ethernet_channel.h

@@ -41,6 +41,8 @@ class EthernetChannel : public Channel {
 
   AE_OBJECT_REFLECT(AE_MMBRS(aether_, poller_, dns_resolver_, address))
 
+  std::optional<Endpoint> endpoint() const override { return address; }
+
   TransportBuildSender TransportBuilder() override;
 
   Endpoint address;

aether/channels/lora_module_channel.h

@@ -37,6 +37,8 @@ class LoraModuleChannel final : public Channel {
 
   AE_OBJECT_REFLECT(AE_MMBRS(access_point_))
 
+  std::optional<Endpoint> endpoint() const override { return std::nullopt; }
+
   ActionPtr<TransportBuilderAction> TransportBuilder() override;
 
   Duration TransportBuildTimeout() const override;

aether/channels/modem_channel.h

@@ -37,6 +37,8 @@ class ModemChannel final : public Channel {
 
   AE_OBJECT_REFLECT(AE_MMBRS(access_point_, address))
 
+  std::optional<Endpoint> endpoint() const override { return address; }
+
   TransportBuildSender TransportBuilder() override;
 
   Duration TransportBuildTimeout() const override;

aether/channels/wifi_channel.h

@@ -42,6 +42,8 @@ class WifiChannel final : public Channel {
   AE_OBJECT_REFLECT(AE_MMBRS(aether_, poller_, resolver_, access_point_,
                              address))
 
+  std::optional<Endpoint> endpoint() const override { return address; }
+
   Duration TransportBuildTimeout() const override;
 
   TransportBuildSender TransportBuilder() override;

aether/client_messages/p2p_message_stream.cpp

@@ -24,6 +24,7 @@
 #include "aether/cloud.h"
 
 #include "aether/cloud_connections/cloud_request.h"
+#include "aether/cloud_connections/cloud_server_connection.h"
 #include "aether/cloud_connections/cloud_subscription.h"
 
 #include "aether/client_messages/client_messages_tele.h"
@@ -48,6 +49,7 @@ class MessageSendStream final : public IStream<AeMessage, AeMessage> {
         }},
         request_policy_);
   }
+
   StreamInfo stream_info() const override { return stream_info_; }
   OutDataEvent::Subscriber out_data_event() override { return out_data_event_; }
   StreamUpdateEvent::Subscriber stream_update_event() override {

aether/client_messages/p2p_message_stream.h

@@ -17,6 +17,9 @@
 #ifndef AETHER_CLIENT_MESSAGES_P2P_MESSAGE_STREAM_H_
 #define AETHER_CLIENT_MESSAGES_P2P_MESSAGE_STREAM_H_
 
+#include <cstdint>
+#include <optional>
+
 #include "aether/common.h"
 
 #include "aether/ae_context.h"
@@ -29,6 +32,8 @@
 #include "aether/cloud_connections/cloud_server_connections.h"
 #include "aether/connection_manager/client_cloud_manager.h"
 
+#include "aether/prepared_packet/packet_encoder.h"
+
 namespace ae {
 class Client;
 class Cloud;

aether/connection_manager/client_cloud_manager.cpp

@@ -199,6 +199,14 @@ GetCloudAction& ClientCloudManager::GetCloud(Uid client_uid) {
   return *action;
 }
 
+Cloud::ptr ClientCloudManager::GetCachedCloud(Uid client_uid) {
+  auto cached = cloud_cache_.find(client_uid);
+  if ((cached == cloud_cache_.end()) || !cached->second.cloud.is_valid()) {
+    return {};
+  }
+  return cached->second.cloud;
+}
+
 void ClientCloudManager::StartListenForCloudUpdate() {
   auto aether = aether_.Load();
   assert(aether && "Aether must be loaded");

aether/connection_manager/client_cloud_manager.h

@@ -89,8 +89,17 @@ class ClientCloudManager : public Obj {
 
   CloudUpdateEvent::Subscriber cloud_update_event();
 
+  /**
+   * \brief Make request for cloud for client_uid.
+   * New request to client cloud is performed or cloud returned from cache.
+   */
   GetCloudAction& GetCloud(Uid client_uid);
 
+  /**
+   * \brief Returns cloud from cache for client_uid or empty Cloud::ptr.
+   */
+  Cloud::ptr GetCachedCloud(Uid client_uid);
+
   AE_OBJECT_REFLECT(AE_MMBRS(aether_, client_, cloud_cache_))
 
   void StartListenForCloudUpdate();

aether/prepared_packet/packet_encoder.cpp

@@ -0,0 +1,75 @@
+#include "aether/prepared_packet/packet_encoder.h"
+
+#include <memory>
+#include <utility>
+
+#include "aether/crypto/ikey_provider.h"
+#include "aether/crypto/sync_crypto_provider.h"
+
+#include "aether/api_protocol/api_context.h"
+#include "aether/api_protocol/sub_api.h"
+
+#include "aether/work_cloud_api/ae_message.h"
+#include "aether/work_cloud_api/work_server_api/authorized_api.h"
+#include "aether/work_cloud_api/work_server_api/login_api.h"
+
+namespace ae::prepared_packet {
+namespace {
+
+class PreparedSendMessageKeyProvider final : public ISyncKeyProvider {
+ public:
+  explicit PreparedSendMessageKeyProvider(PreparedSendMessage& block)
+      : block_{&block} {}
+
+  Key GetKey() const override { return block_->client_to_server_key; }
+
+  CryptoNonce const& Nonce() const override { return block_->next_nonce; }
+
+ private:
+  PreparedSendMessage* block_;
+};
+
+}  // namespace
+
+Result<std::size_t, EncodePacketError> EncodePacket(
+    PreparedSendMessageBlock& prepared_block, DataBuffer const& payload,
+    DataBuffer& out) {
+  if (!prepared_block.is_valid()) {
+    return Error{block_is_invalid};
+  }
+
+  auto send_message = prepared_block.Resolve();
+
+  if (send_message->message_left == 0) {
+    return Error{messages_exhausted};
+  }
+
+  // Match the existing ClientKeyProvider semantics:
+  // consume next nonce before encryption.
+  send_message->next_nonce.Next();
+  --send_message->message_left;
+
+  auto key_provider =
+      std::make_unique<PreparedSendMessageKeyProvider>(*send_message);
+  SyncEncryptProvider encrypt_provider{std::move(key_provider)};
+
+  ProtocolContext protocol_context;
+  LoginApi login_api{protocol_context, encrypt_provider};
+
+  auto api_context = ApiContext{login_api};
+
+  api_context->login_by_alias(
+      send_message->sender_ephemeral,
+      SubApi<AuthorizedApi>{
+          [&](auto& auth_api) {
+            auth_api->send_message(
+                AeMessage{send_message->destination_uid, DataBuffer{payload}});
+          },
+      });
+
+  out = std::move(api_context).Pack();
+
+  return Ok{out.size()};
+}
+
+}  // namespace ae::prepared_packet

aether/prepared_packet/packet_encoder.h

@@ -0,0 +1,46 @@
+/*
+ * Prepared packet encoder.
+ *
+ * EncodePacket only builds Aether packet bytes and advances the reserved nonce
+ * range. It does not send, open sockets, resolve DNS, or know platform
+ * transport.
+ */
+#ifndef AETHER_PREPARED_PACKET_PACKET_ENCODER_H_
+#define AETHER_PREPARED_PACKET_PACKET_ENCODER_H_
+
+#include <string_view>
+
+#include "aether-miscpp/types/result.h"
+
+// IWYU pragma: begin_exports
+#include "aether/prepared_packet/prepared_send_message.h"
+#include "aether/types/data_buffer.h"
+// IWYU pragma: end_exports
+
+namespace ae::prepared_packet {
+
+struct EncodePacketError {
+  int ec;
+  std::string_view msg;
+};
+
+static constexpr inline auto ok = EncodePacketError{0, "Ok!"};
+static constexpr inline auto block_is_invalid =
+    EncodePacketError{1, "PreparedSendMessageBlock is invalid"};
+static constexpr inline auto messages_exhausted =
+    EncodePacketError{2, "Reserved message count exhausted"};
+
+/**
+ * \brief Encode send_message packet for PreparedSendMessageBlock
+ * \param block - prepared send message block; block must be valid.
+ * \param payload - message payload.
+ * \param out - output buffer where result is stored.
+ * \return Result with either out size or error.
+ */
+Result<std::size_t, EncodePacketError> EncodePacket(
+    PreparedSendMessageBlock& block, DataBuffer const& payload,
+    DataBuffer& out);
+
+}  // namespace ae::prepared_packet
+
+#endif  // AETHER_PREPARED_PACKET_PACKET_ENCODER_H_