Logger Module

A simple logging system that provides structured logging with search capabilities.

Logs are stored in hourly files with a consistent format that makes them both human-readable and machine-parseable.

Features

• Structured logging with categories and error types
• Automatic timestamp management
• Multi-line message support
• Search functionality with filtering options
• Human-readable log format

Usage

import freeflowuniverse.herolib.core.logger
import freeflowuniverse.herolib.data.ourtime

// Create a new logger
mut l := logger.new(path: '/var/logs')!

// Log a message
l.log(
    cat: 'system',
    log: 'System started successfully',
    logtype: .stdout
)!

// Log an error
l.log(
    cat: 'system',
    log: 'Failed to connect\nRetrying in 5 seconds...',
    logtype: .error
)!

// Search logs
results := l.search(
    timestamp_from: ourtime.now().warp('-24h'), // Last 24 hours
    cat: 'system',                               // Filter by category
    log: 'failed',                              // Search in message content
    logtype: .error,                            // Only error messages
    maxitems: 100                               // Limit results
)!

Log Format

Each log file is named using the format YYYY-MM-DD-HH.log and contains entries in the following format:

21:23:42
 system     - This is a normal log message
 system     - This is a multi-line message
              second line with proper indentation
              third line maintaining alignment
E error_cat - This is an error message
E             second line of error
E             third line of error

Format Rules

• Time stamps (HH:MM:SS) are written once per second when the log time changes
• Categories are:
• Limited to 10 characters maximum
• Padded with spaces to exactly 10 characters
• Any - in category names are converted to _
• Each line starts with either:
• (space) for normal logs (LogType.stdout)
• E for error logs (LogType.error)
• Multi-line messages maintain consistent indentation (14 spaces after the prefix)

fn new(path string) !Logger

enum LogType {
	stdout
	error
}

struct LogItem {
pub mut:
	timestamp ourtime.OurTime
	cat       string
	log       string
	logtype   LogType
}

struct LogItemArgs {
pub mut:
	timestamp ?ourtime.OurTime
	cat       string
	log       string
	logtype   LogType
}

struct Logger {
pub mut:
	path         pathlib.Path
	lastlog_time i64 // to see in log format, every second we put a time down, we need to know if we are in a new second (logs can come in much faster)
}

fn (mut l Logger) log(args_ LogItemArgs) !

fn (mut l Logger) search(args_ SearchArgs) ![]LogItem

struct SearchArgs {
pub mut:
	timestamp_from ?ourtime.OurTime
	timestamp_to   ?ourtime.OurTime
	cat            string // can be empty
	log            string // any content in here will be looked for
	logtype        LogType
	maxitems       int = 10000
}