kcenon::logger::log_entry Struct Reference

Represents a single log entry with all associated metadata. More...

#include <log_entry.h>

Collaboration diagram for kcenon::logger::log_entry:

Public Member Functions
	log_entry (log_level lvl, const std::string &msg, std::chrono::system_clock::time_point ts=std::chrono::system_clock::now())
	log_entry (log_level lvl, const std::string &msg, const std::string &file, int line, const std::string &function, std::chrono::system_clock::time_point ts=std::chrono::system_clock::now())
	log_entry (log_entry &&) noexcept=default
	Move constructor.
log_entry &	operator= (log_entry &&) noexcept=default
	Move assignment operator.
	log_entry (const log_entry &)=delete
	Deleted copy constructor.
log_entry &	operator= (const log_entry &)=delete
	Deleted copy assignment operator.

Public Attributes
log_level	level
	Severity level of the log message.
small_string_256	message
	The actual log message.
std::chrono::system_clock::time_point	timestamp
	Timestamp when the log entry was created.
std::optional< source_location >	location
	Optional source code location information.
std::optional< small_string_64 >	thread_id
	Optional thread identifier.
std::optional< small_string_128 >	category
	Optional category for log filtering and routing.
std::optional< otlp::otel_context >	otel_ctx
	Optional OpenTelemetry context for trace correlation.
std::optional< log_fields >	fields
	Optional structured fields for key-value logging.

Detailed Description

Represents a single log entry with all associated metadata.

The log_entry structure is the core data type that flows through the logging system. It contains the log message, severity level, timestamp, and optional metadata such as source location and thread information.

The structure is designed for high performance:

• Move-only semantics to avoid copying
• Small string optimization for common string sizes
• Optional fields to minimize memory usage

Note

This structure is move-only. Use std::move() when passing log entries to avoid compilation errors.

Warning

Copy operations are explicitly deleted to prevent performance degradation from accidental copies in high-throughput scenarios.

Since

1.0.0

Examples

advanced_features_demo.cpp, composite_writer_example.cpp, custom_writer_example.cpp, decorator_usage.cpp, security_demo.cpp, structured_logging_example.cpp, and writer_builder_example.cpp.

Definition at line 155 of file log_entry.h.

Constructor & Destructor Documentation

log_entry() [1/4]

kcenon::logger::log_entry::log_entry ( log_level lvl, const std::string & msg, std::chrono::system_clock::time_point ts = std::chrono::system_clock::now() )

inline

Examples

/home/runner/work/logger_system/logger_system/include/kcenon/logger/interfaces/log_entry.h.

Definition at line 231 of file log_entry.h.

        : level(lvl), message(msg), timestamp(ts) {}

log_entry() [2/4]

kcenon::logger::log_entry::log_entry ( log_level lvl, const std::string & msg, const std::string & file, int line, const std::string & function, std::chrono::system_clock::time_point ts = std::chrono::system_clock::now() )

inline

Definition at line 261 of file log_entry.h.

        : level(lvl), message(msg), timestamp(ts),
          location(source_location{file, line, function}) {}

log_entry() [3/4]

kcenon::logger::log_entry::log_entry ( log_entry && )

defaultnoexcept

Move constructor.

Enables efficient transfer of log entries without copying

Since

1.0.0

log_entry() [4/4]

kcenon::logger::log_entry::log_entry ( const log_entry & )

delete

Deleted copy constructor.

Prevents accidental copying for performance reasons

Since

1.0.0

Member Function Documentation

operator=() [1/2]

log_entry & kcenon::logger::log_entry::operator= ( const log_entry & )

delete

Deleted copy assignment operator.

Prevents accidental copying for performance reasons

Since

1.0.0

operator=() [2/2]

log_entry & kcenon::logger::log_entry::operator= ( log_entry && )

defaultnoexcept

Move assignment operator.

Enables efficient transfer of log entries without copying

Since

1.0.0

Examples

/home/runner/work/logger_system/logger_system/include/kcenon/logger/interfaces/log_entry.h.

Member Data Documentation

category

std::optional<small_string_128> kcenon::logger::log_entry::category

Optional category for log filtering and routing.

Allows grouping related log messages (e.g., "database", "network", "security")

Note

Categories are stored efficiently using small_string_128

Examples

/home/runner/work/logger_system/logger_system/include/kcenon/logger/interfaces/log_entry.h.

Definition at line 197 of file log_entry.h.

Referenced by kcenon::logger::structured_log_builder::emit(), kcenon::logger::json_formatter::format(), kcenon::logger::logfmt_formatter::format(), kcenon::logger::template_formatter::resolve_placeholder(), kcenon::logger::filters::category_filter::should_log(), kcenon::logger::sampling::log_sampler::should_sample(), and kcenon::logger::formatted_writer::write().

fields

std::optional<log_fields> kcenon::logger::log_entry::fields

Optional structured fields for key-value logging.

Allows adding arbitrary key-value pairs to log entries for structured logging support. These fields are output by formatters that support structured output (e.g., JSON formatter).

Since

3.1.0

Examples

/home/runner/work/logger_system/logger_system/include/kcenon/logger/interfaces/log_entry.h.

Definition at line 213 of file log_entry.h.

Referenced by kcenon::logger::structured_log_builder::emit(), kcenon::logger::json_formatter::format(), kcenon::logger::logfmt_formatter::format(), kcenon::logger::sampling::log_sampler::get_field_rate(), json_formatter_example(), logfmt_formatter_example(), kcenon::logger::template_formatter::resolve_placeholder(), kcenon::logger::sampling::log_sampler::should_bypass_field(), kcenon::logger::filters::field_exists_filter::should_log(), kcenon::logger::filters::field_range_filter::should_log(), kcenon::logger::filters::field_regex_filter::should_log(), kcenon::logger::filters::field_value_filter::should_log(), template_formatter_example(), and kcenon::logger::formatted_writer::write().

level

log_level kcenon::logger::log_entry::level

Severity level of the log message.

Determines the importance and routing of the message

Examples

/home/runner/work/logger_system/logger_system/include/kcenon/logger/interfaces/log_entry.h, composite_writer_example.cpp, custom_writer_example.cpp, decorator_usage.cpp, and writer_builder_example.cpp.

Definition at line 162 of file log_entry.h.

Referenced by kcenon::logger::buffered_writer::copy_entry(), kcenon::logger::copy_log_entry(), kcenon::logger::compact_formatter::format(), kcenon::logger::json_formatter::format(), kcenon::logger::logfmt_formatter::format(), kcenon::logger::plain_formatter::format(), kcenon::logger::timestamp_formatter::format(), kcenon::logger::network_writer::format_for_network(), main(), kcenon::logger::template_formatter::resolve_placeholder(), kcenon::logger::filters::exact_level_filter::should_log(), kcenon::logger::filters::level_filter::should_log(), kcenon::logger::log_filter::should_log(), kcenon::logger::routing::router_builder::level_condition::should_log(), level_filter::should_log(), kcenon::logger::sampling::log_sampler::should_sample(), kcenon::logger::async::high_performance_async_writer::write(), kcenon::logger::console_writer::write(), kcenon::logger::critical_writer::write(), kcenon::logger::encrypted_writer::write(), kcenon::logger::formatted_writer::write(), kcenon::logger::network_writer::write(), kcenon::logger::otlp_writer::write(), counted_console_writer::write_entry_impl(), and kcenon::logger::critical_writer::write_to_wal().

location

std::optional<source_location> kcenon::logger::log_entry::location

Optional source code location information.

Present when log() is called with file/line/function parameters

Examples

/home/runner/work/logger_system/logger_system/include/kcenon/logger/interfaces/log_entry.h.

Definition at line 183 of file log_entry.h.

Referenced by kcenon::logger::buffered_writer::copy_entry(), kcenon::logger::copy_log_entry(), kcenon::logger::log_collector::impl::enqueue(), kcenon::logger::json_formatter::format(), kcenon::logger::logfmt_formatter::format(), kcenon::logger::plain_formatter::format(), kcenon::logger::timestamp_formatter::format(), kcenon::logger::network_writer::format_for_network(), kcenon::logger::template_formatter::resolve_placeholder(), kcenon::logger::log_filter::should_log(), kcenon::logger::memory::log_entry_pool::pooled_log_entry::to_log_entry(), kcenon::logger::async::high_performance_async_writer::write(), kcenon::logger::encrypted_writer::write(), kcenon::logger::formatted_writer::write(), kcenon::logger::network_writer::write(), kcenon::logger::otlp_writer::write(), and kcenon::logger::critical_writer::write_to_wal().

message

small_string_256 kcenon::logger::log_entry::message

The actual log message.

Uses small_string_256 for efficient storage of messages up to 256 characters

Note

Messages longer than 256 characters will use heap allocation

Examples

/home/runner/work/logger_system/logger_system/include/kcenon/logger/interfaces/log_entry.h, composite_writer_example.cpp, decorator_usage.cpp, and security_demo.cpp.

Definition at line 169 of file log_entry.h.

Referenced by kcenon::logger::buffered_writer::copy_entry(), kcenon::logger::copy_log_entry(), kcenon::logger::compact_formatter::format(), kcenon::logger::json_formatter::format(), kcenon::logger::logfmt_formatter::format(), kcenon::logger::plain_formatter::format(), kcenon::logger::timestamp_formatter::format(), kcenon::logger::console_writer::format_entry(), kcenon::logger::file_writer::format_entry(), kcenon::logger::network_writer::format_for_network(), kcenon::logger::base_writer::format_log_entry(), main(), kcenon::logger::template_formatter::resolve_placeholder(), content_filter::should_log(), kcenon::logger::filters::regex_filter::should_log(), kcenon::logger::log_filter::should_log(), kcenon::logger::routing::router_builder::regex_condition::should_log(), security_filter::should_log(), kcenon::logger::sampling::log_sampler::should_sample(), kcenon::logger::async::high_performance_async_writer::write(), kcenon::logger::encrypted_writer::write(), kcenon::logger::network_writer::write(), kcenon::logger::otlp_writer::write(), and kcenon::logger::critical_writer::write_to_wal().

otel_ctx

std::optional<otlp::otel_context> kcenon::logger::log_entry::otel_ctx

Optional OpenTelemetry context for trace correlation.

Contains trace_id and span_id for distributed tracing

Since

3.0.0

Examples

/home/runner/work/logger_system/logger_system/include/kcenon/logger/interfaces/log_entry.h.

Definition at line 204 of file log_entry.h.

Referenced by kcenon::logger::json_formatter::format(), kcenon::logger::logfmt_formatter::format(), kcenon::logger::template_formatter::resolve_placeholder(), kcenon::logger::formatted_writer::write(), and kcenon::logger::otlp_writer::write().

thread_id

std::optional<small_string_64> kcenon::logger::log_entry::thread_id

Optional thread identifier.

Can be set to track which thread generated the log message

Note

Thread IDs are stored efficiently using small_string_64

Examples

/home/runner/work/logger_system/logger_system/include/kcenon/logger/interfaces/log_entry.h.

Definition at line 190 of file log_entry.h.

Referenced by kcenon::logger::json_formatter::format(), kcenon::logger::logfmt_formatter::format(), kcenon::logger::plain_formatter::format(), kcenon::logger::timestamp_formatter::format(), kcenon::logger::template_formatter::resolve_placeholder(), and kcenon::logger::formatted_writer::write().

timestamp

std::chrono::system_clock::time_point kcenon::logger::log_entry::timestamp

Timestamp when the log entry was created.

Uses system clock for wall-clock time representation

Examples

/home/runner/work/logger_system/logger_system/include/kcenon/logger/interfaces/log_entry.h, and composite_writer_example.cpp.

Definition at line 175 of file log_entry.h.

Referenced by kcenon::logger::buffered_writer::copy_entry(), kcenon::logger::copy_log_entry(), kcenon::logger::logger::impl::dispatch_to_writers(), kcenon::logger::json_formatter::format(), kcenon::logger::logfmt_formatter::format(), kcenon::logger::plain_formatter::format(), kcenon::logger::timestamp_formatter::format(), kcenon::logger::network_writer::format_for_network(), main(), kcenon::logger::template_formatter::resolve_placeholder(), kcenon::logger::async::high_performance_async_writer::write(), kcenon::logger::encrypted_writer::write(), kcenon::logger::formatted_writer::write(), kcenon::logger::network_writer::write(), kcenon::logger::otlp_writer::write(), and kcenon::logger::critical_writer::write_to_wal().

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The documentation for this struct was generated from the following file:

• include/kcenon/logger/interfaces/log_entry.h