nt8-sdk/TASK-04-log-level.md

TASK-04: Add Log Level Filter to BasicLogger

File: src/NT8.Core/Logging/BasicLogger.cs Priority: HIGH No dependencies Estimated time: 20 min

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Background

BasicLogger currently writes every log level to console unconditionally. When EnableVerboseLogging is false in NT8, you want to suppress Debug and Trace output.

The current ILogger interface (check src/NT8.Core/Logging/ILogger.cs) only defines:

• LogDebug, LogInformation, LogWarning, LogError, LogCritical

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Exact Changes Required

1. Add LogLevel enum (check if it already exists first — search the project for LogLevel)

If it does NOT already exist, add it inside BasicLogger.cs or as a separate file in the same folder:

namespace NT8.Core.Logging
{
    /// <summary>
    /// Log severity levels.
    /// </summary>
    public enum LogLevel
    {
        Debug = 0,
        Information = 1,
        Warning = 2,
        Error = 3,
        Critical = 4
    }
}

2. Add MinimumLevel property to BasicLogger

/// <summary>
/// Minimum log level to write. Messages below this level are suppressed.
/// Default is Information.
/// </summary>
public LogLevel MinimumLevel { get; set; }

3. Update constructor to default to Information

public BasicLogger(string categoryName = "")
{
    _categoryName = categoryName;
    MinimumLevel = LogLevel.Information;
}

4. Update WriteLog() to skip below minimum

Add a level parameter and check at the start:

private void WriteLog(LogLevel level, string levelLabel, string message, params object[] args)
{
    if (level < MinimumLevel)
        return;

    var timestamp = DateTime.UtcNow.ToString("yyyy-MM-dd HH:mm:ss.fff");
    var formattedMessage = args.Length > 0 ? String.Format(message, args) : message;
    var category = !String.IsNullOrEmpty(_categoryName) ? String.Format("[{0}] ", _categoryName) : "";
    Console.WriteLine(String.Format("{0} [{1}] {2}{3}", timestamp, levelLabel, category, formattedMessage));
}

5. Update each public method to pass its level

public void LogDebug(string message, params object[] args)
{
    WriteLog(LogLevel.Debug, "DEBUG", message, args);
}

public void LogInformation(string message, params object[] args)
{
    WriteLog(LogLevel.Information, "INFO", message, args);
}

public void LogWarning(string message, params object[] args)
{
    WriteLog(LogLevel.Warning, "WARN", message, args);
}

public void LogError(string message, params object[] args)
{
    WriteLog(LogLevel.Error, "ERROR", message, args);
}

public void LogCritical(string message, params object[] args)
{
    WriteLog(LogLevel.Critical, "CRITICAL", message, args);
}

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Acceptance Criteria

• MinimumLevel = LogLevel.Warning suppresses LogDebug and LogInformation calls
• LogWarning, LogError, LogCritical still write when MinimumLevel = LogLevel.Warning
• Default MinimumLevel is Information (backward compatible)
• verify-build.bat passes
• All existing tests pass (no test should be checking console output for Debug messages)