Configuration

Default Logger

The package-level functions (Info(), Warn(), etc.) use the Default logger which writes to os.Stdout at InfoLevel.

// Full configuration
clog.Configure(&clog.Config{
  Verbose: true,                            // enables debug level + timestamps
  Output:  clog.Stderr(clog.ColorAuto),     // custom output
  Styles:  customStyles,                    // custom visual styles
})

// Toggle verbose mode
clog.SetVerbose(true)

Output

Each Logger writes to an *Output, which bundles an io.Writer with its terminal capabilities (TTY detection, width, color profile):

// Standard constructors
out := clog.Stdout(clog.ColorAuto)                  // os.Stdout with auto-detection
out := clog.Stderr(clog.ColorAlways)                // os.Stderr with forced colours
out := clog.NewOutput(w, clog.ColorNever)           // arbitrary writer, colours disabled
out := clog.TestOutput(&buf)                        // shorthand for NewOutput(w, ColorNever)

Output methods:

Method	Description
`Writer()`	Returns the underlying `io.Writer`
`IsTTY()`	True if the writer is connected to a terminal
`ColorsDisabled()`	True if colours are suppressed for this output
`Width()`	Terminal width (0 for non-TTY, lazily cached)
`RefreshWidth()`	Re-detect terminal width on next `Width()` call
`Renderer()`	Returns the lipgloss renderer

Custom Logger

logger := clog.New(clog.Stderr(clog.ColorAuto))
logger.SetLevel(clog.DebugLevel)
logger.SetReportTimestamp(true)
logger.SetTimeFormat("15:04:05.000")
logger.SetFieldTimeFormat(time.Kitchen)    // format for .Time() fields (default: time.RFC3339)
logger.SetTimeLocation(time.UTC)           // timezone for timestamps (default: time.Local)
logger.SetFieldStyleLevel(clog.TraceLevel) // min level for field value styling (default: InfoLevel)
logger.SetHandler(myHandler)

For simple cases where you just need a writer with default color detection:

logger := clog.NewWriter(os.Stderr) // equivalent to New(NewOutput(os.Stderr, ColorAuto))

Utility Functions

clog.GetLevel()                  // returns the current level of the Default logger
clog.IsVerbose()                 // true if level is Debug or Trace
clog.IsTerminal()                // true if Default output is a terminal
clog.ColorsDisabled()            // true if colours are disabled on the Default logger
clog.SetOutput(out)              // change the output (accepts *Output)
clog.SetOutputWriter(w)          // change the output writer (with ColorAuto)
clog.SetExitFunc(fn)             // override os.Exit for Fatal (useful in tests)
clog.SetHyperlinksEnabled(false) // disable all hyperlink rendering
logger.Output()                  // returns the Logger's *Output

Environment Variables

All env vars follow the pattern {PREFIX}_{SUFFIX}. The default prefix is CLOG.

Suffix	Default env var
`LOG_LEVEL`	`CLOG_LOG_LEVEL`
`HYPERLINK_FORMAT`	`CLOG_HYPERLINK_FORMAT`
`HYPERLINK_PATH_FORMAT`	`CLOG_HYPERLINK_PATH_FORMAT`
`HYPERLINK_FILE_FORMAT`	`CLOG_HYPERLINK_FILE_FORMAT`
`HYPERLINK_DIR_FORMAT`	`CLOG_HYPERLINK_DIR_FORMAT`
`HYPERLINK_LINE_FORMAT`	`CLOG_HYPERLINK_LINE_FORMAT`
`HYPERLINK_COLUMN_FORMAT`	`CLOG_HYPERLINK_COLUMN_FORMAT`

CLOG_LOG_LEVEL=debug ./some-app  # enables debug logging + timestamps
CLOG_LOG_LEVEL=warn ./some-app   # suppresses info messages

Custom Env Prefix

Use SetEnvPrefix to whitelabel the env var names for your application. The custom prefix is checked first, with CLOG_ as a fallback.

clog.SetEnvPrefix("MYAPP")
// Now checks MYAPP_LOG_LEVEL first, then CLOG_LOG_LEVEL
// Now checks MYAPP_HYPERLINK_PATH_FORMAT first, then CLOG_HYPERLINK_PATH_FORMAT
// etc.

This means CLOG_LOG_LEVEL=debug always works as a universal escape hatch, even when the application uses a custom prefix.

NO_COLOR is never prefixed - it follows the no-color.org standard independently.

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