Add OpenTelemetry metrics and traces instrumentation

.github/workflows/build.yml

@@ -35,15 +35,17 @@ jobs:
             packages: "libsqlite3-dev"
             run_tests: true
 
-          - name: "Base + Admin API"
-            cmake_flags: "-DCMAKE_BUILD_TYPE=Release -DENABLE_ADMIN_API=ON"
+          - name: "Base + Admin API + OTEL"
+            cmake_flags: "-DCMAKE_BUILD_TYPE=Release -DENABLE_ADMIN_API=ON -DWITH_OTEL=ON -DCMAKE_PREFIX_PATH=/opt/opentelemetry-cpp"
             packages: ""
             run_tests: true
+            with_otel: true
 
-          - name: "YAML + Admin API"
-            cmake_flags: "-DCMAKE_BUILD_TYPE=Release -DHAVE_YAML=ON -DENABLE_ADMIN_API=ON"
+          - name: "YAML + Admin API + OTEL"
+            cmake_flags: "-DCMAKE_BUILD_TYPE=Release -DHAVE_YAML=ON -DENABLE_ADMIN_API=ON -DWITH_OTEL=ON -DCMAKE_PREFIX_PATH=/opt/opentelemetry-cpp"
             packages: "libyaml-cpp-dev"
             run_tests: true
+            with_otel: true
 
     steps:
       - uses: actions/checkout@v4
@@ -52,6 +54,7 @@ jobs:
 
       - name: Install base dependencies
         run: |
+          sudo add-apt-repository universe -y
           sudo apt-get update
           sudo apt-get install -y \
             build-essential \
@@ -72,6 +75,36 @@ jobs:
         run: |
           sudo apt-get install -y ${{ matrix.config.packages }}
 
+      - name: Install opentelemetry-cpp runtime dependencies
+        if: matrix.config.with_otel
+        run: |
+          sudo apt-get install -y libprotobuf-dev
+
+      - name: Cache opentelemetry-cpp
+        if: matrix.config.with_otel
+        id: cache-otel
+        uses: actions/cache@v4
+        with:
+          path: /opt/opentelemetry-cpp
+          key: otel-cpp-1.24.0-ubuntu-x64
+
+      - name: Build opentelemetry-cpp
+        if: matrix.config.with_otel && steps.cache-otel.outputs.cache-hit != 'true'
+        run: |
+          sudo apt-get install -y libgrpc++-dev protobuf-compiler-grpc || true
+          wget -q https://github.com/open-telemetry/opentelemetry-cpp/archive/refs/tags/v1.24.0.tar.gz
+          tar xzf v1.24.0.tar.gz
+          cmake -S opentelemetry-cpp-1.24.0 -B otel-build \
+            -DCMAKE_BUILD_TYPE=Release \
+            -DCMAKE_INSTALL_PREFIX=/opt/opentelemetry-cpp \
+            -DWITH_OTLP_HTTP=ON \
+            -DWITH_OTLP_GRPC=OFF \
+            -DBUILD_TESTING=OFF \
+            -DWITH_BENCHMARK=OFF \
+            -DWITH_EXAMPLES=OFF
+          cmake --build otel-build -j$(nproc)
+          sudo cmake --install otel-build
+
       - name: Configure CMake
         run: |
           mkdir -p build
@@ -271,7 +304,15 @@ jobs:
             git
             wget
 
+      - name: Cache Cygwin libraries
+        id: cache-cygwin-libs
+        uses: actions/cache@v4
+        with:
+          path: C:\cygwin\usr\local
+          key: cygwin-gtest-1.14.0
+
       - name: Build and install googletest from source
+        if: steps.cache-cygwin-libs.outputs.cache-hit != 'true'
         shell: C:\cygwin\bin\bash.exe --login --norc -eo pipefail -o igncr '{0}'
         run: |
           cd /tmp
@@ -330,7 +371,15 @@ jobs:
             git
             wget
 
+      - name: Cache Cygwin libraries
+        id: cache-cygwin-libs
+        uses: actions/cache@v4
+        with:
+          path: C:\cygwin\usr\local
+          key: cygwin-gtest-1.14.0-yaml-0.7.0
+
       - name: Build and install googletest from source
+        if: steps.cache-cygwin-libs.outputs.cache-hit != 'true'
         shell: C:\cygwin\bin\bash.exe --login --norc -eo pipefail -o igncr '{0}'
         run: |
           cd /tmp
@@ -343,6 +392,7 @@ jobs:
           make install
 
       - name: Build and install yaml-cpp from source
+        if: steps.cache-cygwin-libs.outputs.cache-hit != 'true'
         shell: C:\cygwin\bin\bash.exe --login --norc -eo pipefail -o igncr '{0}'
         run: |
           cd /tmp

CLAUDE.md

@@ -351,10 +351,22 @@ Use separate build directories for different CMake configurations to avoid lengt
 build/        - default build (without optional features)
 build_sqlite/ - build with -DHAVE_SQLITE=ON
 build_debug/  - debug build with -DCMAKE_BUILD_TYPE=Debug
+build_otel/   - build with -DWITH_OTEL=ON (requires vcpkg)
 build_test/   - test data and converted worlds (not for compilation)
 ```
 **Always warn the user when changing build directories or running cmake/make in a different directory.**
 
+### OpenTelemetry Build (WITH_OTEL)
+opentelemetry-cpp is installed via vcpkg at `~/repos/vcpkg`. Always pass the toolchain file and prefix path:
+```bash
+cmake -S . -B build_otel \
+  -DCMAKE_BUILD_TYPE=Release \
+  -DWITH_OTEL=ON \
+  -DCMAKE_TOOLCHAIN_FILE=~/repos/vcpkg/scripts/buildsystems/vcpkg.cmake \
+  -DCMAKE_PREFIX_PATH=~/repos/vcpkg/installed/x64-linux
+make -C build_otel -j$(($(nproc)/2))
+```
+
 ### File Encoding - CRITICAL
 **Proper workflow for editing KOI8-R files:**
 

CMakeLists.txt

@@ -10,7 +10,6 @@ set_property(GLOBAL PROPERTY USE_FOLDERS ON)
 
 set(SOURCES
 		src/engine/structs/blocking_queue.cpp
-		src/engine/db/influxdb.cpp
 		src/engine/core/heartbeat.cpp
 		src/engine/core/heartbeat_commands.cpp
 		src/gameplay/abilities/abilities_rollsystem.cpp
@@ -98,6 +97,8 @@ set(SOURCES
 		src/utils/levenshtein.cpp
 		src/gameplay/mechanics/liquid.cpp
 		src/utils/logger.cpp
+		src/utils/logging/file_log_sender.cpp
+		src/utils/logging/log_manager.cpp
 		src/gameplay/magic/magic.cpp
 		src/gameplay/magic/magic_items.cpp
 		src/gameplay/magic/magic_rooms.cpp
@@ -158,6 +159,8 @@ set(SOURCES
 		src/engine/structs/flags.hpp
 		src/utils/id_converter.cpp
 		src/utils/utils_time.cpp
+		src/utils/tracing/trace_manager.cpp
+		src/engine/observability/otel_trace_sender.cpp
 		src/utils/thread_pool.cpp
 		src/gameplay/mechanics/title.cpp
 		src/gameplay/statistics/top.cpp
@@ -461,7 +464,12 @@ set(SOURCES
 		src/engine/db/player_index.cpp
 		src/gameplay/skills/addshot.cpp
 		src/gameplay/classes/mob_classes_info.cpp
-		src/gameplay/classes/recalc_mob_params_by_vnum.cpp)
+		src/gameplay/classes/recalc_mob_params_by_vnum.cpp
+		src/engine/observability/otel_provider.cpp
+		src/engine/observability/otel_traces.cpp
+		src/engine/observability/otel_metrics.cpp
+		src/engine/observability/otel_helpers.cpp
+		src/engine/observability/otel_log_sender.cpp)
 
 
 
@@ -511,7 +519,6 @@ set(HEADERS
 		src/administration/accounts.h
 		src/engine/core/action_targeting.h
 		src/engine/structs/blocking_queue.h
-		src/engine/db/influxdb.h
 		src/engine/core/heartbeat_commands.h
 		src/gameplay/mechanics/weather.h
 		src/gameplay/core/game_limits.h
@@ -605,6 +612,9 @@ set(HEADERS
 		src/utils/levenshtein.h
 		src/gameplay/mechanics/liquid.h
 		src/utils/logger.h
+		src/utils/logging/log_sender.h
+		src/utils/logging/file_log_sender.h
+		src/utils/logging/log_manager.h
 		src/gameplay/magic/magic.h
 		src/gameplay/magic/magic_items.h
 		src/gameplay/magic/magic_rooms.h
@@ -662,6 +672,10 @@ set(HEADERS
 		src/engine/core/sysdep.h
 		src/engine/network/telnet.h
 		src/utils/utils_time.h
+		src/utils/tracing/trace_sender.h
+		src/utils/tracing/noop_trace_sender.h
+		src/utils/tracing/trace_manager.h
+		src/engine/observability/otel_trace_sender.h
 		src/gameplay/mechanics/title.h
 		src/gameplay/statistics/top.h
 		src/utils/utils.h
@@ -898,6 +912,12 @@ set(HEADERS
 		src/gameplay/mechanics/tutelar.h
 		src/gameplay/skills/addshot.h
 		src/engine/db/player_index.h
+		src/engine/observability/otel_provider.h
+		src/engine/observability/otel_traces.h
+		src/engine/observability/otel_metrics.h
+		src/engine/observability/otel_helpers.h
+		src/engine/observability/otel_log_sender.h
+		src/utils/logging/log_sender.h
 		src/gameplay/classes/recalc_mob_params_by_vnum.h)
 
 # Build types
@@ -1204,6 +1224,29 @@ else ()
 	message(STATUS "SQLite is turned off.")
 endif ()
 
+# OpenTelemetry support
+if (WITH_OTEL)
+	message(STATUS "OpenTelemetry integration: ENABLED")
+
+	# Find OpenTelemetry from vcpkg
+	find_package(opentelemetry-cpp CONFIG REQUIRED)
+
+	# Define WITH_OTEL for preprocessor
+	add_definitions(-DWITH_OTEL)
+
+	# Link OpenTelemetry libraries
+	target_link_libraries(circle.library
+		opentelemetry-cpp::api
+		opentelemetry-cpp::sdk
+		opentelemetry-cpp::ext
+		opentelemetry-cpp::otlp_http_exporter
+		opentelemetry-cpp::otlp_http_metric_exporter
+		opentelemetry-cpp::otlp_http_log_record_exporter
+		opentelemetry-cpp::resources
+	)
+else()
+	message(STATUS "OpenTelemetry integration: DISABLED")
+endif()
 # YAML support
 if (HAVE_YAML)
 	# Try to find yaml-cpp via CMake config first
@@ -1330,7 +1373,7 @@ if (UNIX AND NOT CYGWIN)
 	set(DEFAULT_WITH_ASAN YES)
 else ()
 	set(DEFAULT_WITH_ASAN NO)
-endif ()
+endif()
 option(WITH_ASAN "Compile with ASAN" ${DEFAULT_WITH_ASAN})
 
 if (WITH_ASAN)
@@ -1450,6 +1493,9 @@ if (BUILD_TESTS)
 	add_subdirectory(tests)
 endif ()
 
+option(WITH_OTEL "Enable OpenTelemetry integration" OFF)
+
+# vim: set ts=4 sw=4 ai tw=0 noet syntax=cmake :
 
 # =============================================================================
 # Data directories setup for running server from build directory

lib/misc/configuration.xml

@@ -114,4 +114,40 @@
 		</server>
 	</statistics>
 	-->
+	<!--
+	Настройки телеметрии OpenTelemetry (OTLP HTTP).
+	Требует сборки с -DWITH_OTEL=ON.
+	Без этой сборки секция будет прочитана, но проигнорирована.
+
+	Переменные в service/name:
+	  ${port}    - порт, на котором запущен сервер (из аргументов командной строки)
+	  ${host}    - имя хоста (hostname)
+	  ${version} - версия сервиса (из service/version ниже)
+
+	Режимы логирования (logs/mode):
+	  file-only  - логи только в файл (по умолчанию)
+	  otel-only  - логи только в OTEL (Loki)
+	  duplicate  - логи и в файл, и в OTEL
+	-->
+	<telemetry>
+		<enabled>true</enabled>
+		<otlp>
+			<metrics>
+				<endpoint>http://localhost:4318/v1/metrics</endpoint>
+			</metrics>
+			<traces>
+				<endpoint>http://localhost:4318/v1/traces</endpoint>
+			</traces>
+			<logs_otlp>
+				<endpoint>http://localhost:4318/v1/logs</endpoint>
+			</logs_otlp>
+		</otlp>
+		<service>
+			<name>bylins-${host}-${port}</name>
+			<version>1.0.0</version>
+		</service>
+		<logs>
+			<mode>duplicate</mode>
+		</logs>
+	</telemetry>
 </configuration>

src/engine/core/comm.cpp

@@ -37,6 +37,7 @@
 #include "engine/db/world_characters.h"
 #include "engine/entities/entities_constants.h"
 #include "administration/shutdown_parameters.h"
+#include "engine/observability/otel_provider.h"
 #include "external_trigger.h"
 #include "handler.h"
 #include "gameplay/clans/house.h"
@@ -673,7 +674,9 @@ int main_function(int argc, char **argv) {
 					   "  -h             Print this command line argument help.\n"
 					   "  -o <file>      Write log to <file> instead of stderr.\n"
 					   "  -r             Restrict MUD -- no new players allowed.\n"
-					   "  -s             Suppress special procedure assignments.\n", argv[0]);
+					   "  -s             Suppress special procedure assignments.\n"
+				   "\n"
+				   	   "  -S <database>  Use SQLite database for world loading.\n", argv[0]);
 				exit(0);
 
 			default: printf("SYSERR: Unknown option -%c in argument string.\n", *(argv[pos] + 1));
@@ -683,7 +686,9 @@ int main_function(int argc, char **argv) {
 					   "  -h             Print this command line argument help.\n"
 					   "  -o <file>      Write log to <file> instead of stderr.\n"
 					   "  -r             Restrict MUD -- no new players allowed.\n"
-					   "  -s             Suppress special procedure assignments.\n", argv[0]);
+					   "  -s             Suppress special procedure assignments.\n"
+				   "\n"
+				   	   "  -S <database>  Use SQLite database for world loading.\n", argv[0]);
 				exit(1);
 			break;
 		}
@@ -720,6 +725,7 @@ int main_function(int argc, char **argv) {
 	// directories are created in the working directory (next to the binary),
 	// not inside the data directory.
 	runtime_config.setup_logs();
+	runtime_config.setup_telemetry(port);
 	logfile = runtime_config.logs(SYSLOG).handle();
 	if (chdir(dir) < 0) {
 		perror("\r\nSYSERR: Fatal error changing to data directory");
@@ -759,6 +765,11 @@ void stop_game(ush_int port) {
 
 	log("Opening mother connection.");
 	mother_desc = init_socket(port);
+	if (mother_desc < 0) {
+		log("SYSERR: Failed to bind to port %d. Server cannot start.", port);
+		log("Please check if another instance is running or if you have permission to use this port.");
+		exit(1);
+	}
 
 #ifdef ENABLE_ADMIN_API
 	if (runtime_config.admin_api_enabled()) {
@@ -826,6 +837,9 @@ void stop_game(ush_int port) {
 	game_loop(mother_desc);
 #endif
 
+	// Shutdown OTEL providers to flush remaining telemetry
+	observability::OtelProvider::Instance().Shutdown();
+
 	FlushPlayerIndex();
 
 	// храны надо сейвить до Crash_save_all_rent(), иначе будем брать бабло у чара при записи
@@ -1009,9 +1023,9 @@ socket_t init_socket(ush_int port) {
 	sa.sin_addr = *(get_bind_addr());
 
 	if (bind(s, (struct sockaddr *) &sa, sizeof(sa)) < 0) {
-		perror("SYSERR: bind");
+		log("SYSERR: bind() failed - port %d is already in use or permission denied", port);
 		CLOSE_SOCKET(s);
-		exit(1);
+		return -1;
 	}
 	nonblock(s);
 	listen(s, 5);
@@ -2178,8 +2192,7 @@ RETSIGTYPE checkpointing(int/* sig*/) {
 }
 
 RETSIGTYPE hupsig(int/* sig*/) {
-	log("SYSERR: Received SIGHUP, SIGINT, or SIGTERM.  Shutting down...");
-	exit(1);        // perhaps something more elegant should substituted
+	shutdown_parameters.shutdown_now();
 }
 
 #endif                // CIRCLE_UNIX