rpc: add a new RPC to get current txpool backlog (sizes and fees)

src/cryptonote_core/cryptonote_core.cpp

@@ -246,6 +246,12 @@ namespace cryptonote
     return m_blockchain_storage.get_transactions_blobs(txs_ids, txs, missed_txs);
   }
   //-----------------------------------------------------------------------------------------------
+  bool core::get_txpool_backlog(std::vector<tx_backlog_entry>& backlog) const
+  {
+    m_mempool.get_transaction_backlog(backlog);
+    return true;
+  }
+  //-----------------------------------------------------------------------------------------------
   bool core::get_transactions(const std::vector<crypto::hash>& txs_ids, std::list<transaction>& txs, std::list<crypto::hash>& missed_txs) const
   {
     return m_blockchain_storage.get_transactions(txs_ids, txs, missed_txs);

src/cryptonote_core/cryptonote_core.h

@@ -427,6 +427,13 @@ namespace cryptonote
       */
      bool get_pool_transactions(std::list<transaction>& txs) const;
      
+     /**
+      * @copydoc tx_memory_pool::get_txpool_backlog
+      *
+      * @note see tx_memory_pool::get_txpool_backlog
+      */
+     bool get_txpool_backlog(std::vector<tx_backlog_entry>& backlog) const;
+     
      /**
       * @copydoc tx_memory_pool::get_transactions
       *

src/cryptonote_core/tx_pool.cpp

@@ -553,6 +553,17 @@ namespace cryptonote
     });
   }
   //------------------------------------------------------------------
+  void tx_memory_pool::get_transaction_backlog(std::vector<tx_backlog_entry>& backlog) const
+  {
+    CRITICAL_REGION_LOCAL(m_transactions_lock);
+    CRITICAL_REGION_LOCAL1(m_blockchain);
+    const uint64_t now = time(NULL);
+    m_blockchain.for_all_txpool_txes([&backlog, now](const crypto::hash &txid, const txpool_tx_meta_t &meta, const cryptonote::blobdata *bd){
+      backlog.push_back({meta.blob_size, meta.fee, meta.receive_time - now});
+      return true;
+    });
+  }
+  //------------------------------------------------------------------
   void tx_memory_pool::get_transaction_stats(struct txpool_stats& stats) const
   {
     CRITICAL_REGION_LOCAL(m_transactions_lock);

src/cryptonote_core/tx_pool.h

@@ -242,6 +242,13 @@ namespace cryptonote
      */
     void get_transaction_hashes(std::vector<crypto::hash>& txs) const;
 
+    /**
+     * @brief get (size, fee, receive time) for all transaction in the pool
+     *
+     * @param txs return-by-reference that data
+     */
+    void get_transaction_backlog(std::vector<tx_backlog_entry>& backlog) const;
+
     /**
      * @brief get a summary statistics of all transaction hashes in the pool
      *

src/rpc/core_rpc_server.cpp

@@ -1725,6 +1725,26 @@ namespace cryptonote
     return true;
   }
   //------------------------------------------------------------------------------------------------------------------------------
+  bool core_rpc_server::on_get_txpool_backlog(const COMMAND_RPC_GET_TRANSACTION_POOL_BACKLOG::request& req, COMMAND_RPC_GET_TRANSACTION_POOL_BACKLOG::response& res, epee::json_rpc::error& error_resp)
+  {
+    if(!check_core_busy())
+    {
+      error_resp.code = CORE_RPC_ERROR_CODE_CORE_BUSY;
+      error_resp.message = "Core is busy.";
+      return false;
+    }
+
+    if (!m_core.get_txpool_backlog(res.backlog))
+    {
+      error_resp.code = CORE_RPC_ERROR_CODE_INTERNAL_ERROR;
+      error_resp.message = "Failed to get txpool backlog";
+      return false;
+    }
+
+    res.status = CORE_RPC_STATUS_OK;
+    return true;
+  }
+  //------------------------------------------------------------------------------------------------------------------------------
 
   const command_line::arg_descriptor<std::string> core_rpc_server::arg_rpc_bind_port = {
       "rpc-bind-port"

src/rpc/core_rpc_server.h

@@ -125,6 +125,7 @@ namespace cryptonote
         MAP_JON_RPC_WE_IF("get_alternate_chains",on_get_alternate_chains,       COMMAND_RPC_GET_ALTERNATE_CHAINS, !m_restricted)
         MAP_JON_RPC_WE_IF("relay_tx",            on_relay_tx,                   COMMAND_RPC_RELAY_TX, !m_restricted)
         MAP_JON_RPC_WE_IF("sync_info",           on_sync_info,                  COMMAND_RPC_SYNC_INFO, !m_restricted)
+        MAP_JON_RPC_WE_IF("get_txpool_backlog",  on_get_txpool_backlog,         COMMAND_RPC_GET_TRANSACTION_POOL_BACKLOG, !m_restricted)
       END_JSON_RPC_MAP()
     END_URI_MAP2()
 
@@ -182,6 +183,7 @@ namespace cryptonote
     bool on_get_alternate_chains(const COMMAND_RPC_GET_ALTERNATE_CHAINS::request& req, COMMAND_RPC_GET_ALTERNATE_CHAINS::response& res, epee::json_rpc::error& error_resp);
     bool on_relay_tx(const COMMAND_RPC_RELAY_TX::request& req, COMMAND_RPC_RELAY_TX::response& res, epee::json_rpc::error& error_resp);
     bool on_sync_info(const COMMAND_RPC_SYNC_INFO::request& req, COMMAND_RPC_SYNC_INFO::response& res, epee::json_rpc::error& error_resp);
+    bool on_get_txpool_backlog(const COMMAND_RPC_GET_TRANSACTION_POOL_BACKLOG::request& req, COMMAND_RPC_GET_TRANSACTION_POOL_BACKLOG::response& res, epee::json_rpc::error& error_resp);
     //-----------------------
 
 private:

src/rpc/core_rpc_server_commands_defs.h

@@ -1071,6 +1071,33 @@ namespace cryptonote
     };
   };
 
+  struct tx_backlog_entry
+  {
+    uint64_t blob_size;
+    uint64_t fee;
+    uint64_t time_in_pool;
+  };
+
+  struct COMMAND_RPC_GET_TRANSACTION_POOL_BACKLOG
+  {
+    struct request
+    {
+      BEGIN_KV_SERIALIZE_MAP()
+      END_KV_SERIALIZE_MAP()
+    };
+
+    struct response
+    {
+      std::string status;
+      std::vector<tx_backlog_entry> backlog;
+
+      BEGIN_KV_SERIALIZE_MAP()
+        KV_SERIALIZE(status)
+        KV_SERIALIZE_CONTAINER_POD_AS_BLOB(backlog)
+      END_KV_SERIALIZE_MAP()
+    };
+  };
+
   struct txpool_histo
   {
     uint32_t txs;