Create a database-only shared library (#1521)

* Build and test a database-only shared library

Author: daxhaw

production/cmake/gaia.cmake

@@ -14,8 +14,9 @@ cmake_minimum_required(VERSION 3.16)
 # - GAIA_ROOT: Gaia root directory. Default: /opt/gaia.
 # - GAIA_INC: Gaia include directory. Default: ${GAIA_ROOT}/include.
 # - GAIA_BIN: Gaia bin directory. Default: ${GAIA_ROOT}/bin.
-# - GAIA_LIB_DIR: libgaia.so directory. Default: ${GAIA_ROOT}/lib.
+# - GAIA_LIB_DIR: libgaia.so and libgaia_db.so directory. Default: ${GAIA_ROOT}/lib.
 # - GAIA_LIB: Automatically set by CMake if libgaia.so is found.
+# - GAIA_DB_LIB: Automatically set by CMake if libgaia_db.so is found.
 # - GAIA_GAIAC_CMD: The gaiac command. Default: ${GAIA_BIN}/gaiac.
 # - GAIA_GAIAT_CMD: The gaiat command. Default: ${GAIA_BIN}/gaiat.
 # - GAIA_DEFAULT_DIRECT_ACCESS_GENERATED_DIR: The process_schema() function puts the generated Direct Access code
@@ -64,6 +65,11 @@ if(NOT GAIA_LIB)
   message(FATAL_ERROR "Gaia library is not found!")
 endif()
 
+find_library(GAIA_DB_LIB gaia_db PATHS ${GAIA_LIB_DIR})
+if(NOT GAIA_DB_LIB)
+  message(FATAL_ERROR "Gaia database-only library is not found!")
+endif()
+
 if(NOT DEFINED GAIA_DEFAULT_DIRECT_ACCESS_GENERATED_DIR)
   set(GAIA_DEFAULT_DIRECT_ACCESS_GENERATED_DIR ${CMAKE_BINARY_DIR}/gaia_generated/direct_access)
   file(MAKE_DIRECTORY ${GAIA_DEFAULT_DIRECT_ACCESS_GENERATED_DIR})

production/cmake/gaia_internal.cmake

@@ -441,6 +441,7 @@ function(add_example)
 
   # Not all the examples have a ruleset file.
   if(DEFINED ARG_RULESET_FILE)
+    set(GAIA_LIB_NAME "gaia")
     get_filename_component(RULESET_NAME ${ARG_RULESET_FILE} NAME)
     string(REPLACE ".ruleset" "" RULESET_NAME ${RULESET_NAME})
 
@@ -458,14 +459,16 @@ function(add_example)
     endif()
 
     string(APPEND ARG_SRC_FILES ";" ${GAIA_GENERATED_CODE}/rules/${RULESET_NAME}/${RULESET_NAME}_ruleset.cpp)
+  else()
+    set(GAIA_LIB_NAME "gaia_db")
   endif()
 
   add_executable(${ARG_NAME}
     ${ARG_SRC_FILES}
   )
 
   target_link_libraries(${ARG_NAME}
-    gaia
+    "${GAIA_LIB_NAME}"
     "${DAC_LIB_NAME}"
     Threads::Threads
   )

production/db/core/src/gaia_ptr_api.cpp

@@ -424,29 +424,31 @@ void update_payload(gaia_ptr_t& obj, size_t data_size, const void* data)
         return;
     }
 
-    auto new_data = reinterpret_cast<const uint8_t*>(data);
-    auto old_data = reinterpret_cast<const uint8_t*>(old_this->data());
-
-    field_position_list_t changed_fields = compute_payload_diff(obj.type(), old_data, new_data);
-
     const type_metadata_t& metadata = type_registry_t::instance().get(obj.type());
-    if (metadata.has_value_linked_relationship())
+    if (client_t::has_commit_trigger() || metadata.has_value_linked_relationship())
     {
-        auto_connect(
-            obj.id(),
-            obj.type(),
-            type_id_mapping_t::instance().get_table_id(obj.type()),
-            obj.references(),
-            new_data,
-            changed_fields);
-    }
+        auto new_data = reinterpret_cast<const uint8_t*>(data);
+        auto old_data = reinterpret_cast<const uint8_t*>(old_this->data());
+        field_position_list_t changed_fields = compute_payload_diff(obj.type(), old_data, new_data);
 
-    obj.finalize_update(old_offset);
+        if (metadata.has_value_linked_relationship())
+        {
+            auto_connect(
+                obj.id(),
+                obj.type(),
+                type_id_mapping_t::instance().get_table_id(obj.type()),
+                obj.references(),
+                new_data,
+                changed_fields);
+        }
 
-    if (client_t::is_valid_event(obj.type()))
-    {
-        client_t::log_event(triggers::event_type_t::row_update, obj.type(), obj.id(), changed_fields);
+        if (client_t::has_commit_trigger() && client_t::is_valid_event(obj.type()))
+        {
+            client_t::log_event(triggers::event_type_t::row_update, obj.type(), obj.id(), changed_fields);
+        }
     }
+
+    obj.finalize_update(old_offset);
 }
 
 void remove(gaia_ptr_t& object, bool force)

production/db/inc/core/db_client.hpp

@@ -73,6 +73,7 @@ class client_t
     static inline gaia_txn_id_t get_current_txn_id();
     static void clear_shared_memory();
     static inline void set_commit_trigger(triggers::commit_trigger_fn trigger_fn);
+    static inline bool has_commit_trigger();
     static inline bool is_ping_session_open();
     static inline bool is_ddl_session_open();
 

production/db/inc/core/db_client.inc

@@ -33,6 +33,11 @@ inline void client_t::set_commit_trigger(triggers::commit_trigger_fn trigger_fn)
     s_txn_commit_trigger = trigger_fn;
 }
 
+inline bool client_t::has_commit_trigger()
+{
+    return (s_txn_commit_trigger != nullptr);
+}
+
 inline int client_t::get_session_socket_for_txn()
 {
     return s_session_socket;

production/examples/direct_access/CMakeLists.txt

@@ -31,4 +31,4 @@ add_executable(direct_access
 
 target_add_gaia_generated_sources(direct_access)
 target_include_directories(direct_access PRIVATE ${GAIA_INC})
-target_link_libraries(direct_access PRIVATE ${GAIA_LIB} Threads::Threads)
+target_link_libraries(direct_access PRIVATE ${GAIA_DB_LIB} Threads::Threads)

production/examples/direct_access_multithread/CMakeLists.txt

@@ -31,4 +31,4 @@ add_executable(direct_access_multithread
 
 target_add_gaia_generated_sources(direct_access_multithread)
 target_include_directories(direct_access_multithread PRIVATE ${GAIA_INC})
-target_link_libraries(direct_access_multithread PRIVATE ${GAIA_LIB} Threads::Threads)
+target_link_libraries(direct_access_multithread PRIVATE ${GAIA_DB_LIB} Threads::Threads)

production/examples/direct_access_vlr/CMakeLists.txt

@@ -31,4 +31,4 @@ add_executable(direct_access_vlr
 
 target_add_gaia_generated_sources(direct_access_vlr)
 target_include_directories(direct_access_vlr PRIVATE ${GAIA_INC})
-target_link_libraries(direct_access_vlr PRIVATE ${GAIA_LIB} Threads::Threads)
+target_link_libraries(direct_access_vlr PRIVATE ${GAIA_DB_LIB} Threads::Threads)

production/examples/hello/CMakeLists.txt

@@ -41,4 +41,4 @@ add_executable(hello
 target_add_gaia_generated_sources(hello)
 target_include_directories(hello PRIVATE ${GAIA_INC})
 target_link_directories(hello PRIVATE ${GAIA_LIB_DIR})
-target_link_libraries(hello PRIVATE gaia rt Threads::Threads)
+target_link_libraries(hello PRIVATE ${GAIA_LIB} rt Threads::Threads)

production/examples/incubator/CMakeLists.txt

@@ -41,4 +41,4 @@ add_executable(incubator
 target_add_gaia_generated_sources(incubator)
 target_include_directories(incubator PRIVATE ${GAIA_INC})
 target_link_directories(incubator PRIVATE ${GAIA_LIB_DIR})
-target_link_libraries(incubator PRIVATE gaia rt Threads::Threads)
+target_link_libraries(incubator PRIVATE ${GAIA_LIB} rt Threads::Threads)