spdlog_setup (spdlog setup)

Overview

Header-only spdlog file-based setup library for convenience in initializing spdlog. Inspired by spdlog-config for using TOML configuration, a format that is simple and easy-to-read.

Requirements

Requires at least CMake 3.3, g++-4.9 for Linux, or MSVC2015 with MSBuild for Windows, providing sufficient C++11 features.

g++-4.8 will notably fail because of the missing std::regex implementation. MSVC2013 will fail too as it does not accept noexcept, which is used in some of the functions.

Tested against:

• g++-4.9
• g++-5
• g++-6
• g++-7
• g++-8
• clang-3.6
• clang-3.7
• clang-3.8
• clang-3.9
• clang-4.0
• clang-5.0
• clang-6.0
• clang-7
• cl (v140 / MSVC2015)
• cl (v141 / MSVC2017)

Features

• Header-only (check How to Install to extract out the header files).
• Initialization of spdlog sinks, patterns and loggers based on TOML configuration file.
• Tag replacement (e.g. "{tagname}-log.txt") within the TOML configuration file.
• Throw exception describing the error during the parsing of the config file.

Changelog

See CHANGELOG.md for more details.

Repository Checkout

Since this repository has other git-based dependencies as git submodules, use the command: git clone --recursive https://github.com/guangie88/spdlog_setup.git in order to clone all the submodule dependencies.

If the repository has already been cloned without the submodules, then instead run: git submodule update --init --recursive in order to clone all the submodule dependencies.

Dependencies

This repository uses the following external dependencies directly:

• Catch (only for unit-tests, not included in installation)
• spdlog

In addition, the following dependencies are inlined as part of the include:

• cpptoml
• fmt

How to Build

This guide prefers a CMake out-of-source build style. For build with unit tests, add -DSPDLOG_SETUP_INCLUDE_UNIT_TESTS=ON during the CMake configuration.

How to Install

If a recent enough spdlog is already available, and unit tests are not to be run, it is possible to just copy the spdlog_setup directory within include into another solution for header-only include, as long as spdlog can be found in that solution.

If spdlog is not available, the installation step of CMake can copy out the entire list of header files required for spdlog_setup into the installation directory, including spdlog. To change the installation directory, add -DCMAKE_INSTALL_PREFIX=<path-to-install> during the CMake configuration.

Linux (GCC)

In the root directory after git cloning:

Debug without Installation

• mkdir build-debug
• cd build-debug
• cmake .. -DCMAKE_BUILD_TYPE=Debug -DSPDLOG_SETUP_INCLUDE_UNIT_TESTS=ON
• cmake --build .

Now the unit test executable should be compiled and residing in build-debug/spdlog_setup_unit_test.

Release with Installation

• mkdir build-release
• cd build-release
• cmake .. -DCMAKE_BUILD_TYPE=Release -DSPDLOG_SETUP_INCLUDE_UNIT_TESTS=ON -DCMAKE_INSTALL_PREFIX=install
• cmake --build . --target install

Now the unit test executable should be compiled and residing in build-release/spdlog_setup_unit_test.

The header files should be installed in build-release/install/include.

Windows (MSVC2015 as Example)

Ensure that Microsoft Build Tools 2015 and Visual C++ Build Tools 2015 (or Visual Studio 2015) have been installed.

In the root directory after git cloning:

• mkdir build
• cd build
• cmake .. -G "Visual Studio 14 Win64" -DSPDLOG_SETUP_INCLUDE_UNIT_TESTS=ON -DCMAKE_INSTALL_PREFIX=install
• (Debug) cmake --build . --config Debug
• (Release with installation) cmake --build . --config Release --target install

Now the unit test executable should be compiled and residing in

• (Debug) build/Debug/spdlog_setup_unit_test.exe or
• (Release) build/Release/spdlog_setup_unit_test.exe.

The header files should be installed in build/install/include.

Supported Sinks

• stdout_sink_st
• stdout_sink_mt
• stderr_sink_st
• stderr_sink_mt
• color_stdout_sink_st
• color_stdout_sink_mt
• color_stderr_sink_st
• color_stderr_sink_mt
• basic_file_sink_st
• basic_file_sink_mt
• rotating_file_sink_st
• rotating_file_sink_mt
• daily_file_sink_st
• daily_file_sink_mt
• null_sink_st
• null_sink_mt
• syslog_sink (only for Linux, SPDLOG_ENABLE_SYSLOG preprocessor definition must be defined before any spdlog/spdlog_setup header is included)

Currently ostream_sink and dist_sink do not fit into the use case and are not supported.

For more information about how the above sinks work in spdlog, please refer to the original spdlog sinks wiki page at: https://github.com/gabime/spdlog/wiki/4.-Sinks.

TOML Configuration Example

Static File Configuration

# level is optional for both sinks and loggers
# level for error logging is 'err', not 'error'
# _st => single threaded, _mt => multi threaded
# syslog_sink is automatically thread-safe by default, no need for _mt suffix

# max_size supports suffix
# - T (terabyte)
# - G (gigabyte)
# - M (megabyte)
# - K (kilobyte)
# - or simply no suffix (byte)

# check out https: // github.com/gabime/spdlog/wiki/3.-Custom-formatting
global_pattern = "[%Y-%m-%dT%T%z] [%L] <%n>: %v"

[[sink]]
name = "console_st"
type = "stdout_sink_st"

[[sink]]
name = "console_mt"
type = "stdout_sink_mt"

[[sink]]
name = "color_console_st"
type = "color_stdout_sink_st"

[[sink]]
name = "color_console_mt"
type = "color_stdout_sink_mt"

[[sink]]
name = "file_out"
type = "basic_file_sink_st"
filename = "log/spdlog_setup.log"
# truncate field is optional
# truncate = false (default)
level = "info"
# optional flag to indicate the set - up to create the log dir first
create_parent_dir = true

[[sink]]
name = "file_err"
type = "basic_file_sink_mt"
filename = "log/spdlog_setup_err.log"
truncate = true
level = "err"
# to show that create_parent_dir is indeed optional(defaults to false)

[[sink]]
name = "rotate_out"
type = "rotating_file_sink_st"
base_filename = "log/rotate_spdlog_setup.log"
max_size = "1M"
max_files = 10
level = "info"

[[sink]]
name = "rotate_err"
type = "rotating_file_sink_mt"
base_filename = "log/rotate_spdlog_setup_err.log"
max_size = "1M"
max_files = 10
level = "err"

[[sink]]
name = "daily_out"
type = "daily_file_sink_st"
base_filename = "log/daily_spdlog_setup.log"
rotation_hour = 17
rotation_minute = 30
level = "info"

[[sink]]
name = "daily_err"
type = "daily_file_sink_mt"
base_filename = "log/daily_spdlog_setup_err.log"
rotation_hour = 17
rotation_minute = 30
level = "err"

[[sink]]
name = "null_sink_st"
type = "null_sink_st"

[[sink]]
name = "null_sink_mt"
type = "null_sink_mt"

# only works for Linux
[[sink]]
name = "syslog_st"
type = "syslog_sink_st"
# generally no need to fill up the optional fields below
# ident = "" (default)
# syslog_option = 0 (default)
# syslog_facility = LOG_USER (default macro value)

# only works for Linux
[[sink]]
name = "syslog_mt"
type = "syslog_sink_mt"
# generally no need to fill up the optional fields below
# ident = "" (default)
# syslog_option = 0 (default)
# syslog_facility = LOG_USER (default macro value)

# only works for Windows
[[sink]]
name = "msvc_st"
type = "msvc_sink_st"

# only works for Windows
[[sink]]
name = "msvc_mt"
type = "msvc_sink_mt"

[[pattern]]
name = "succient"
value = "%c-%L: %v"

[[logger]]
name = "root"
sinks = [
    "console_st", "console_mt",
    "color_console_st", "color_console_mt",
    "daily_out", "daily_err",
    "file_out", "file_err",
    "rotate_out", "rotate_err",
    "null_sink_st", "null_sink_mt",
    "syslog_st", "syslog_mt"]
level = "trace"

[[logger]]
name = "windows_only"
sinks = ["msvc_st", "msvc_mt"]

[[logger]]
name = "console"
sinks = ["console_st", "console_mt"]
pattern = "succient"

# Async

[global_thread_pool]
queue_size = 8192
num_threads = 1

[[thread_pool]]
name = "tp"
queue_size = 4096
num_threads = 2

[[logger]]
type = "async"
name = "global_async"
sinks = ["console_mt"]
pattern = "succient"

[[logger]]
type = "async"
name = "local_async"
sinks = ["console_mt"]
pattern = "succient"
thread_pool = "tp"
overflow_policy = "overrun_oldest"  # block (default) | overrun_oldest

Tagged-Base Pre-TOML File Configuration

# level is optional for both sinks and loggers
# level for error logging is 'err', not 'error'

# max_size supports suffix
# - T (terabyte)
# - G (gigabyte)
# - M (megabyte)
# - K (kilobyte)
# - or simply no suffix (byte)

[[sink]]
name = "console"
type = "stdout_sink_mt"

[[sink]]
name = "rotate_out"
type = "rotating_file_sink_mt"
base_filename = "log/{index}-info/simple-{path}.log"
max_size = "1M"
max_files = 10
level = "info"
# optional flag to indicate the set - up to create the log dir first
create_parent_dir = true

[[sink]]
name = "simple_err"
type = "basic_file_sink_mt"
filename = "log/{index}-err/simple-{path}.log"
truncate = false
level = "err"
# optional flag to indicate the set - up to create the log dir first
create_parent_dir = true

[[logger]]
name = "root"
sinks = ["console", "rotate_out", "simple_err"]
level = "trace"

Use Examples

Static Configuration File

#include "spdlog_setup/conf.h"

#include <iostream>
#include <string>

int main() {
    try {
        // spdlog_setup::setup_error thrown if file not found
        spdlog_setup::from_file("log_conf.toml");

        // assumes that root logger has been initialized
        auto logger = spdlog::get("root");
        logger->trace("trace message");
        logger->debug("debug message");
        logger->info("info message");
        logger->warn("warn message");
        logger->error("error message");
        logger->critical("critical message");

        // ...
    } catch (const spdlog_setup::setup_error &) {
        // ...
    } catch (const std::exception &) {
        // ...
    }
}

Tagged Based Configuration File

#include "spdlog_setup/conf.h"

#include <string>

int main(const int argc, const char * argv[]) {
    // assumes both index and path are given by command line arguments

    try {
        // gets index integer, e.g. 123
        const auto index = std::stoi(argv[1]);

        // gets path string, e.g. a/b/c
        const auto path = std::string(argv[2]);

        // performs parsing with dynamic tag value replacements
        // tags are anything content that contains {xxx}, where xxx is the name
        // of the tag to be replaced
        spdlog_setup::from_file_with_tag_replacement(
            "log_conf.pre.toml",
            // replaces {index} with actual value in current variable index via
            // fmt mechanism
            fmt::arg("index", index),
            // replaces {path} with actual value in current variable path
            fmt::arg("path", path));

        auto logger = spdlog::get("root");
        // ...
    } catch (const spdlog_setup::setup_error &) {
        // ...
    } catch (const std::exception &) {
        // ...
    }
}

Notes

• Make sure that the directory for the log files to reside in exists before using spdlog, unless the create_parent_dir flag is set to true for the sink.
• For the current set of unit tests, the working directory must be at the git root directory or in build directory so that the TOML configuration files in config directory can be found.

Contributions

Pull requests are welcome!

To make the code formatting more objective, clang-format is used to format all the source code files.

Please try to run

./run-clang-format.sh

which will pull the appropriate Docker image to run the formatting command over the entire repository directory.

If your docker command requires sudo, then you will need to run it as

sudo sh ./run-clang-format.sh

Alternatively, you could also try to set up your own clang-format (currently this repository uses version 7), and run

clang-format -i path_to_h_cpp_file

over the changed files.