Level API

The Level enum defines the standard log levels with numeric priorities and colors.

Overview

Log levels control which messages are processed and help filter output based on severity. Higher priority numbers indicate more severe conditions. Each level has an associated ANSI color for console output.

Enum Values with Colors

Level	Priority	Color Code	Color	Description
trace	5	36	Cyan	Very detailed debugging information
debug	10	34	Blue	Debugging information for development
info	20	37	White	General informational messages
success	25	32	Green	Successful operation confirmations
warning	30	33	Yellow	Warning messages indicating potential issues
err	40	31	Red	Error conditions that should be addressed
fail	45	35	Magenta	Operation failures that may be recoverable
critical	50	91	Bright Red	Critical system errors requiring immediate attention

Whole-Line Coloring

Logly colors the entire log line including timestamp, level tag, and message:

\x1b[33m[2024-01-15 10:30:45] [WARNING] Disk space low\x1b[0m

This provides better visual separation between log levels in console output.

Methods

priority() u8

Returns the numeric priority of the level.

const level = Level.warning;
const p = level.priority(); // Returns 30

asString() []const u8

Returns the uppercase string representation of the level.

const level = Level.err;
const name = level.asString(); // Returns "ERR"

color() []const u8

Returns the ANSI color code for the level.

const level = Level.warning;
const c = level.color(); // Returns "33"

Custom Levels

Create custom log levels with their own priority, name, and color:

// Add a custom "AUDIT" level with priority 35 and purple color
try logger.addCustomLevel("audit", 35, "35");  // "35" = magenta

// Use the custom level
try logger.custom("audit", "User login detected");
// Output: [2024-01-15 10:30:45] [AUDIT] User login detected (in magenta)

Custom Level Colors

You can use any ANSI color code or combination:

Code	Color	Example
31	Red	Error messages
32	Green	Success indicators
33	Yellow	Warnings
34	Blue	Debug info
35	Magenta	Custom/audit
36	Cyan	Trace/verbose
37	White	Standard info
91	Bright Red	Critical
92	Bright Green	Highlights
93	Bright Yellow	Important

Color Modifiers

Combine colors with modifiers using semicolons:

try logger.addCustomLevel("alert", 42, "31;1");     // Bold red
try logger.addCustomLevel("notice", 22, "36;4");    // Underline cyan
try logger.addCustomLevel("highlight", 38, "33;7"); // Reverse yellow

Modifier	Code	Effect
Bold	1	31;1 = bold red
Underline	4	34;4 = underline blue
Reverse	7	32;7 = reverse green

Level Filtering

Global Level Filter

Set the minimum log level globally:

var config = Config.default();
config.level = .warning; // Only warning and above
logger.configure(config);

Per-Sink Level Filter

Each sink can have its own level filter:

_ = try logger.addSink(.{
    .level = .err,      // Minimum level
    .max_level = .fail, // Maximum level (optional)
});

Module-Level Filtering

Set different log levels for different modules:

try logger.setModuleLevel("database", .debug);
try logger.setModuleLevel("http", .warning);

Windows Support

On Windows, enable ANSI colors at application startup:

_ = logly.Terminal.enableAnsiColors();

This enables Virtual Terminal Processing for proper color display. No-op on Linux/macOS.