Log-Lite

Log-Lite is a small size, high performance tool for logging events. Library is written in C#,has no external dependencies and rely on in-code configuration.

Table of contents

• Features
• Examples
• Todos

Features

• 4 log levels (info, warning, error, fatal)
• Custom logs formatting
• Writing to Console
• Writing to file
• Writing to multiple sources at once
• Archiving log files by given criteria
• Selecting log levels to handle

Examples

// creating basic logger that will write to file logs.txt
var fileLogWriter = new FileLogWriter();
var logger = new Logger(fileLogWriter);

// creating basic logger that will write to console
var consoleLogWriter = new ConsoleLogWriter();
var logger = new Logger(consoleLogWriter);

// loggers can have multiple log writers
var fileLogWriter = new FileLogWriter();
var consoleLogWriter = new ConsoleLogWriter();
var logger = new Logger(fileLogWriter, consoleLogWriter);

// writing logs
logger.Debug("MESSAGE");
logger.Info("MESSAGE");
logger.Warning("MESSAGE");
logger.Error("MESSAGE");
logger.Fatal("MESSAGE");

// default log format can be changed using a formatter
// every writer can have it's own formatter
// in a FileLogWriter good way to set it is by using a builder
var simpleFormatter = new CustomLogFormatter((i) => $"{i.Level} {DateTime.Now} {i.Message}");
var fileLogWriter = FileLogWriter.Builder()
    .Formatter(simpleFormatter)
    .Build();
var logger = new Logger(fileLogWriter);

// we can specify which file to log and what levels to log
var errorsFileInfo = new SystemFileInfo("errors.txt");
var logLevels = new LogLevel[] { LogLevel.ERROR, LogLevel.FATAL };
var errorsFileLogWriter = FileLogWriter.Builder()
    .SetFileInfo(errorsFileInfo)
    .SetAllowedLogLevels(logLevels)
    .Build();
var logger = new Logger(errorsFileLogWriter);
// now only ERRORS and FATALS will be logging to errors.txt file

// to keep log file small and useful we would want to archive it on some point
var fileInfo = new SystemFileInfo("logs.txt");
var checker = new SizeArchiveNecessityChecker(fileInfo, 1, MemoryUnit.MB);
var fileNameFormatter = new MillisecondsArchiveFileNameFormatter("json");
var archiver = new FileArchiver(fileInfo, "Archive", checker, fileNameFormatter: fileNameFormatter);
var fileLogWriter = FileLogWriter.Builder()
    .SetFileInfo(fileInfo)
    .SetFileArchiver(archiver)
    .Build();
// now if logs.txt will have more than 1MB data it will be moved to Archive directory with name changed to current timestamp as milliseconds
// new fresh logs.txt file will be created
// log files can be also archived based on their age using TimeArchiveNecessityChecker

// my personal favourite setup
// global writer for all kinds of logs, writes to logs.txt and archives them in Archive directory when they are older then 1 day
var fileInfo = new SystemFileInfo("logs.txt");
var checker = new TimeArchiveNecessityChecker(fileInfo, 1, TimeUnit.DAYS);
var archiver = new FileArchiver(fileInfo, "Archive", checker);
var fileWriter = FileLogWriter.Builder()
    .SetFileInfo(fileInfo)
    .SetFileArchiver(archiver)
    .Build();

// errors writer for separating dangerous logs, writes to errors.txt archives them in Archive_Errors directory when they reach 1MB size
var errorsFileInfo = new SystemFileInfo("errors.txt");
var errorsChecker = new SizeArchiveNecessityChecker(errorsFileInfo, 1, MemoryUnit.MB);
var errorsArchiver = new FileArchiver(errorsFileInfo, "Archive_Errors", errorsChecker);
var logLevels = new LogLevel[] { LogLevel.ERROR, LogLevel.FATAL };
var errorsFileWriter = FileLogWriter.Builder()
    .SetFileInfo(errorsFileInfo)
    .SetFileArchiver(errorsArchiver)
    .SetAllowedLogLevels(logLevels)
    .Build();

// console writer for simple logging and instant debugging
var simpleFormatter = new CustomLogFormatter((i) => $"{i.Message}");
var consoleWriter = new ConsoleLogWriter(simpleFormatter);

var logger = new Logger(fileWriter, errorsFileWriter, consoleWriter);

Todos

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