send basic stacktrace

Author: dmehala

dd-trace-cpp

@@ -2,8 +2,11 @@
 
 #include <datadog/telemetry/telemetry.h>
 
+#include <exception>
+
 #include "datadog_context.h"
 #include "ngx_http_datadog_module.h"
+#include "telemetry_util.h"
 
 extern "C" {
 #include <ngx_config.h>
@@ -29,8 +32,6 @@ static bool is_datadog_tracing_enabled(
     return loc_conf->enable_tracing && core_loc_conf->log_subrequest;
   }
 }
-#define CURRENT_FRAME \
-  std::format("{}:{} in {}", __FILE__, __LINE__, __PRETTY_FUNCTION__)
 
 ngx_int_t on_enter_block(ngx_http_request_t *request) noexcept try {
   auto core_loc_conf = static_cast<ngx_http_core_loc_conf_t *>(
@@ -54,7 +55,7 @@ ngx_int_t on_enter_block(ngx_http_request_t *request) noexcept try {
     try {
       context->on_change_block(request, core_loc_conf, loc_conf);
     } catch (const std::exception &e) {
-      telemetry::report_error_log(e.what());
+      telemetry::report_error_log(e.what(), CURRENT_FRAME(request));
       // The DatadogContext may be broken, destroy it so that we don't
       // attempt to continue tracing.
       destroy_datadog_context(request);
@@ -63,7 +64,7 @@ ngx_int_t on_enter_block(ngx_http_request_t *request) noexcept try {
   }
   return NGX_DECLINED;
 } catch (const std::exception &e) {
-  telemetry::report_error_log(e.what());
+  telemetry::report_error_log(e.what(), CURRENT_FRAME(request));
   ngx_log_error(NGX_LOG_ERR, request->connection->log, 0,
                 "Datadog instrumentation failed for request %p: %s", request,
                 e.what());
@@ -86,7 +87,7 @@ ngx_int_t on_access(ngx_http_request_t *request) noexcept try {
   }
   return NGX_DECLINED;
 } catch (const std::exception &e) {
-  telemetry::report_error_log(e.what());
+  telemetry::report_error_log(e.what(), CURRENT_FRAME(request));
   ngx_log_error(NGX_LOG_ERR, request->connection->log, 0,
                 "Datadog instrumentation failed for request %p: %s", request,
                 e.what());
@@ -100,7 +101,7 @@ ngx_int_t on_log_request(ngx_http_request_t *request) noexcept {
   try {
     context->on_log_request(request);
   } catch (const std::exception &e) {
-    telemetry::report_error_log(e.what());
+    telemetry::report_error_log(e.what(), CURRENT_FRAME(request));
     ngx_log_error(NGX_LOG_ERR, request->connection->log, 0,
                   "Datadog instrumentation failed for request %p: %s", request,
                   e.what());
@@ -117,7 +118,7 @@ ngx_int_t on_header_filter(ngx_http_request_t *request) noexcept {
   try {
     return context->on_header_filter(request);
   } catch (const std::exception &e) {
-    telemetry::report_error_log(e.what());
+    telemetry::report_error_log(e.what(), CURRENT_FRAME(request));
     ngx_log_error(NGX_LOG_ERR, request->connection->log, 0,
                   "Datadog instrumentation failed for request %p: %s", request,
                   e.what());
@@ -142,7 +143,7 @@ ngx_int_t request_body_filter(ngx_http_request_t *request,
   try {
     return context->request_body_filter(request, chain);
   } catch (const std::exception &e) {
-    telemetry::report_error_log(e.what());
+    telemetry::report_error_log(e.what(), CURRENT_FRAME(request));
     ngx_log_error(NGX_LOG_ERR, request->connection->log, 0,
                   "Datadog instrumentation failed in request body filter for "
                   "request %p: %s",
@@ -166,7 +167,7 @@ ngx_int_t on_output_body_filter(ngx_http_request_t *request,
   try {
     return context->on_output_body_filter(request, chain);
   } catch (const std::exception &e) {
-    telemetry::report_error_log(e.what());
+    telemetry::report_error_log(e.what(), CURRENT_FRAME(request));
     ngx_log_error(NGX_LOG_ERR, request->connection->log, 0,
                   "Datadog instrumentation failed for request %p: %s", request,
                   e.what());

src/datadog_handler.cpp

@@ -12,6 +12,7 @@
 #include "global_tracer.h"
 #include "ngx_http_datadog_module.h"
 #include "string_util.h"
+#include "telemetry_util.h"
 #include "tracing_library.h"
 
 namespace datadog {
@@ -63,7 +64,7 @@ static ngx_int_t expand_span_variable(ngx_http_request_t* request,
 
   return NGX_OK;
 } catch (const std::exception& e) {
-  telemetry::report_error_log(e.what());
+  telemetry::report_error_log(e.what(), CURRENT_FRAME(request));
   ngx_log_error(NGX_LOG_ERR, request->connection->log, 0,
                 "failed to expand %V"
                 " for request %p: %s",

src/datadog_variable.cpp

@@ -0,0 +1,38 @@
+#pragma once
+
+#include <format>
+#include <string_view>
+
+#include "string_util.h"
+
+extern "C" {
+#include <ngx_http.h>
+}
+
+namespace datadog::nginx {
+
+constexpr std::string_view relative_filepath(
+    std::string_view absolute_filepath) {
+  constexpr std::string_view prefix = "nginx-datadog";
+  size_t pos = absolute_filepath.find(prefix);
+  return pos != std::string_view::npos ? absolute_filepath.substr(pos)
+                                       : absolute_filepath;
+}
+
+inline std::string make_current_frame(ngx_http_request_t *request,
+                                      std::string_view file, size_t line,
+                                      std::string_view function) {
+  // clang-format off
+  return std::format("Exception catched:\n"
+                     "   at {} ({}:{})\n"
+                     "   at {}", function, file, line,
+                                to_string_view(request->uri));
+  // clang-format on
+}
+
+}  // namespace datadog::nginx
+
+#define CURRENT_FRAME(request)                                        \
+  datadog::nginx::make_current_frame(                                 \
+      request, datadog::nginx::relative_filepath(__FILE__), __LINE__, \
+      __FUNCTION__)