Skeleton of db_plugin created #172

libraries/chain/chain_controller.cpp

@@ -723,6 +723,9 @@ void chain_controller::_apply_block(const signed_block& next_block)
  // notify observers that the block has been applied
  // TODO: do this outside the write lock...? 
  applied_block( next_block ); //emit
+ if (_currently_replaying_blocks)
+ applied_irreversible_block(next_block);
+
 
 } FC_CAPTURE_AND_RETHROW( (next_block.block_num()) ) }
 
@@ -1167,9 +1170,13 @@ void chain_controller::initialize_chain(chain_initializer_interface& starter)
 } FC_CAPTURE_AND_RETHROW() }
 
 chain_controller::chain_controller(database& database, fork_database& fork_db, block_log& blocklog,
- chain_initializer_interface& starter, unique_ptr<chain_administration_interface> admin)
+ chain_initializer_interface& starter, unique_ptr<chain_administration_interface> admin,
+ const applied_irreverisable_block_func& applied_func)
  : _db(database), _fork_db(fork_db), _block_log(blocklog), _admin(std::move(admin)) {
 
+ if (applied_func)
+ applied_irreversible_block.connect(*applied_func);
+
  initialize_indexes();
  starter.register_types(*this, _db);
 
@@ -1194,6 +1201,12 @@ chain_controller::~chain_controller() {
 void chain_controller::replay() {
  ilog("Replaying blockchain");
  auto start = fc::time_point::now();
+
+ auto on_exit = fc::make_scoped_exit([this](){
+ _currently_replaying_blocks = false;
+ });
+ _currently_replaying_blocks = true;
+
  auto last_block = _block_log.read_head();
  if (!last_block) {
  elog("No blocks in block log; skipping replay");
@@ -1353,6 +1366,7 @@ void chain_controller::update_last_irreversible_block()
  auto block = fetch_block_by_number(block_to_write);
  assert(block);
  _block_log.append(*block);
+ applied_irreversible_block(*block);
  }
 
  // Trim fork_database and undo histories

libraries/chain/include/eos/chain/chain_controller.hpp

@@ -47,6 +47,7 @@
 namespace eos { namespace chain {
  using database = chainbase::database;
  using boost::signals2::signal;
+ using applied_irreverisable_block_func = fc::optional<signal<void(const signed_block&)>::slot_type>;
  struct path_cons_list;
 
  /**
@@ -56,7 +57,8 @@ namespace eos { namespace chain {
  class chain_controller {
  public:
  chain_controller(database& database, fork_database& fork_db, block_log& blocklog,
- chain_initializer_interface& starter, unique_ptr<chain_administration_interface> admin);
+ chain_initializer_interface& starter, unique_ptr<chain_administration_interface> admin,
+ const applied_irreverisable_block_func& applied_func = {});
  chain_controller(chain_controller&&) = default;
  ~chain_controller();
 
@@ -70,6 +72,15 @@ namespace eos { namespace chain {
  */
  signal<void(const signed_block&)> applied_block;
 
+ /**
+ * This signal is emitted after irreversible block is written to disk.
+ *
+ * You may not yield from this callback because the blockchain is holding
+ * the write lock and may be in an "inconstant state" until after it is
+ * released.
+ */
+ signal<void(const signed_block&)> applied_irreversible_block;
+
  /**
  * This signal is emitted any time a new transaction is added to the pending
  * block state.
@@ -377,6 +388,7 @@ namespace eos { namespace chain {
  deque<SignedTransaction> _pending_transactions;
 
  bool _currently_applying_block = false;
+ bool _currently_replaying_blocks = false;
  uint64_t _skip_flags = 0;
 
  flat_map<uint32_t,block_id_type> _checkpoints;

plugins/CMakeLists.txt

@@ -2,6 +2,7 @@ add_subdirectory(net_plugin)
 #add_subdirectory(p2p_plugin)
 add_subdirectory(http_plugin)
 add_subdirectory(database_plugin)
+add_subdirectory(db_plugin)
 add_subdirectory(chain_plugin)
 add_subdirectory(chain_api_plugin)
 add_subdirectory(producer_plugin)

plugins/chain_plugin/CMakeLists.txt

@@ -3,7 +3,7 @@ add_library( chain_plugin
  chain_plugin.cpp
  ${HEADERS} )
 
-target_link_libraries( chain_plugin database_plugin eos_native_contract eos_chain appbase )
+target_link_libraries( chain_plugin database_plugin db_plugin eos_native_contract eos_chain appbase )
 target_include_directories( chain_plugin PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}/include" )
 
 install( TARGETS

plugins/chain_plugin/chain_plugin.cpp

@@ -6,6 +6,8 @@
 #include <eos/chain/config.hpp>
 #include <eos/chain/types.hpp>
 
+#include <eos/db_plugin/db_plugin.hpp>
+
 #include <eos/native_contract/native_contract_chain_initializer.hpp>
 #include <eos/native_contract/native_contract_chain_administrator.hpp>
 #include <eos/native_contract/staked_balance_objects.hpp>
@@ -108,10 +110,16 @@ void chain_plugin::plugin_initialize(const variables_map& options) {
  if (options.at("replay-blockchain").as<bool>()) {
  ilog("Replay requested: wiping database");
  app().get_plugin<database_plugin>().wipe_database();
+ if (db_plugin* db = app().find_plugin<db_plugin>()) {
+ db->wipe_database();
+ }
  }
  if (options.at("resync-blockchain").as<bool>()) {
  ilog("Resync requested: wiping blocks");
  app().get_plugin<database_plugin>().wipe_database();
+ if (db_plugin* db = app().find_plugin<db_plugin>()) {
+ db->wipe_database();
+ }
  fc::remove_all(my->block_log_dir);
  }
  if (options.at("skip-transaction-signatures").as<bool>()) {
@@ -144,6 +152,11 @@ void chain_plugin::plugin_initialize(const variables_map& options) {
 void chain_plugin::plugin_startup() 
 { try {
  auto& db = app().get_plugin<database_plugin>().db();
+ eos::chain::applied_irreverisable_block_func applied_func;
+ if (db_plugin* plugin = app().find_plugin<db_plugin>()) {
+ ilog("Blockchain configured with external database.");
+ applied_func = [plugin](const chain::signed_block& b) { plugin->applied_irreversible_block(b); };
+ }
 
  FC_ASSERT( fc::exists( my->genesis_file ), 
  "unable to find genesis file '${f}', check --genesis-json argument", 
@@ -160,7 +173,7 @@ void chain_plugin::plugin_startup()
  my->block_logger = block_log(my->block_log_dir);
  my->chain_id = genesis.compute_chain_id();
  my->chain = chain_controller(db, *my->fork_db, *my->block_logger,
- initializer, native_contract::make_administrator());
+ initializer, native_contract::make_administrator(), applied_func);
 
  if(!my->readonly) {
  ilog("starting chain in read/write mode");

plugins/db_plugin/CMakeLists.txt

@@ -0,0 +1,16 @@
+file(GLOB HEADERS "include/eos/db_plugin/*.hpp")
+add_library( db_plugin
+ db_plugin.cpp
+ ${HEADERS} )
+
+target_link_libraries( db_plugin chain_plugin eos_chain appbase )
+target_include_directories( db_plugin PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}/include" )
+
+install( TARGETS
+ db_plugin
+
+ RUNTIME DESTINATION bin
+ LIBRARY DESTINATION lib
+ ARCHIVE DESTINATION lib
+)
+install( FILES ${HEADERS} DESTINATION "include/eos/db_plugin" )