Class Logger

Main DevLogr Logger class providing structured logging with visual enhancements.

The Logger class is the heart of DevLogr, offering:

Multiple log levels (error, warning, info, debug, trace, success)
Animated spinners with automatic fallbacks
Task management integration with listr2
JSON output mode for machine parsing
Terminal-aware formatting with color and emoji support
Zero-configuration setup with environment variable overrides

Example: Basic Usage

import { createLogger } from '@neofork/devlogr';

const log = createLogger('my-app');

log.info('Application starting...');
log.success('Setup complete!');
log.error('Something went wrong', error);

Example: Spinner Usage

const log = createLogger('deploy');

log.startSpinner('Deploying application...');
// ... do work ...
log.succeedSpinner('Deployment successful!');

Example: Task Management

const log = createLogger('build');

await log.runTasks('Build Process', [
  { title: 'Compile TypeScript', task: () => compileTS() },
  { title: 'Bundle Assets', task: () => bundleAssets() },
  { title: 'Generate Documentation', task: () => generateDocs() }
]);

Constructors

constructor

new Logger(prefix: string): Logger
Parameters
- prefix: string
Returns Logger
- Defined in logger.ts:69

Methods

`Static`setLevel

setLevel(level: LogLevel): void
Set the global log level for all Logger instances. Overrides environment variable configuration.
Parameters
- level: LogLevel
  The minimum log level to display
Returns void
- Defined in logger.ts:85

`Static`resetLevel

resetLevel(): void
Reset the global log level to use environment-based configuration.

Returns void
- Defined in logger.ts:92

info

info(message: string, ...args: unknown[]): void
Log an informational message.
Parameters
- message: string
  The main message to log
- ...args: unknown[]
  Additional arguments to include in the log output
Returns void
- Defined in logger.ts:106

error

error(message: string, error?: unknown, ...args: unknown[]): void
Log an error message with optional error object.
Parameters
- message: string
  The error message to log
- Optionalerror: unknown
  Optional error object or additional data
- ...args: unknown[]
  Additional arguments to include in the log output
Returns void
- Defined in logger.ts:117

warning

warning(message: string, ...args: unknown[]): void
Log a warning message.
Parameters
- message: string
  The warning message to log
- ...args: unknown[]
  Additional arguments to include in the log output
Returns void
- Defined in logger.ts:128

warn

warn(message: string, ...args: unknown[]): void
Alias for warning() method.
Parameters
- message: string
  The warning message to log
- ...args: unknown[]
  Additional arguments to include in the log output
Returns void
- Defined in logger.ts:138

debug

debug(message: string, ...args: unknown[]): void
Log a debug message (only shown when debug level is enabled).
Parameters
- message: string
  The debug message to log
- ...args: unknown[]
  Additional arguments to include in the log output
Returns void
- Defined in logger.ts:148

trace

trace(message: string, ...args: unknown[]): void
Log a trace message (only shown when trace level is enabled).
Parameters
- message: string
  The trace message to log
- ...args: unknown[]
  Additional arguments to include in the log output
Returns void
- Defined in logger.ts:158

success

success(message: string, ...args: unknown[]): void
Log a success message with positive visual styling.
Parameters
- message: string
  The success message to log
- ...args: unknown[]
  Additional arguments to include in the log output
Returns void
- Defined in logger.ts:168

title

title(message: string, ...args: unknown[]): void
Log a title message with prominent visual styling.
Parameters
- message: string
  The title message to log
- ...args: unknown[]
  Additional arguments to include in the log output
Returns void
- Defined in logger.ts:178

task

task(message: string, ...args: unknown[]): void
Log a task message indicating work in progress.
Parameters
- message: string
  The task message to log
- ...args: unknown[]
  Additional arguments to include in the log output
Returns void
- Defined in logger.ts:188

plain

plain(message: string, ...args: unknown[]): void
Log a plain message without any visual styling or symbols.
Parameters
- message: string
  The plain message to log
- ...args: unknown[]
  Additional arguments to include in the log output
Returns void
- Defined in logger.ts:198

startSpinner

startSpinner(text?: string, options?: Omit<SpinnerOptions, "text">): void
Start an animated spinner with optional text and styling options.

Spinners provide visual feedback for long-running operations. They automatically fall back to simple task messages in JSON mode or when the terminal doesn't support ANSI escape sequences.
Parameters
- Optionaltext: string
  Text to display alongside the spinner (defaults to "Processing...")
- Optionaloptions: Omit<SpinnerOptions, "text">
  Optional spinner configuration (color, style, etc.)
Returns void
Example
```
log.startSpinner('Installing dependencies...');
// ... perform work ...
log.succeedSpinner('Dependencies installed!');
```
Example: With custom options
```
log.startSpinner('Deploying...', { color: 'yellow' });
```
- Defined in logger.ts:228

updateSpinnerText

updateSpinnerText(text: string): void
Update the text of the currently active spinner.
Parameters
- text: string
  New text to display with the spinner
Returns void
- Defined in logger.ts:274

stopSpinner

stopSpinner(): void
Stop the current spinner without displaying any completion message.

Returns void
- Defined in logger.ts:288

completeSpinner

completeSpinner(
type: "error" | "info" | "success" | "warning",
text?: string,
): void
Complete the current spinner with a specific completion type and message.
Parameters
- type: "error" | "info" | "success" | "warning"
  Type of completion (success, error, warning, info)
- Optionaltext: string
  Optional completion message (uses default if not provided)
Returns void
- Defined in logger.ts:318

completeSpinnerWithSuccess

completeSpinnerWithSuccess(text?: string): void
Complete the current spinner with a success message.
Parameters
- Optionaltext: string
  Optional success message
Returns void
- Defined in logger.ts:361

completeSpinnerWithError

completeSpinnerWithError(text?: string): void
Complete the current spinner with an error message.
Parameters
- Optionaltext: string
  Optional error message
Returns void
- Defined in logger.ts:370

completeSpinnerWithWarning

completeSpinnerWithWarning(text?: string): void
Complete the current spinner with a warning message.
Parameters
- Optionaltext: string
  Optional warning message
Returns void
- Defined in logger.ts:379

completeSpinnerWithInfo

completeSpinnerWithInfo(text?: string): void
Complete the current spinner with an info message.
Parameters
- Optionaltext: string
  Optional info message
Returns void
- Defined in logger.ts:388

succeedSpinner

succeedSpinner(text?: string): void
Complete the current spinner with a success message (short alias).
Parameters
- Optionaltext: string
  Optional success message
Returns void
Example
```
log.startSpinner('Uploading files...');
log.succeedSpinner('Upload complete!');
```
- Defined in logger.ts:403

failSpinner

failSpinner(text?: string): void
Complete the current spinner with an error message (short alias).
Parameters
- Optionaltext: string
  Optional error message
Returns void
- Defined in logger.ts:412

warnSpinner

warnSpinner(text?: string): void
Complete the current spinner with a warning message (short alias).
Parameters
- Optionaltext: string
  Optional warning message
Returns void
- Defined in logger.ts:421

infoSpinner

infoSpinner(text?: string): void
Complete the current spinner with an info message (short alias).
Parameters
- Optionaltext: string
  Optional info message
Returns void
- Defined in logger.ts:430

runTasks

runTasks<T = any>(
    title: string,
    tasks: ListrTask<T, any, any>[],
    options?: {
        concurrent?: boolean;
        exitOnError?: boolean;
        context?: T;
        rendererOptions?: any;
    },
): Promise<T>
Execute a listr2 task list with proper logger integration
Type Parameters
- T = any
Parameters
- title: string
- tasks: ListrTask<T, any, any>[]
- Optionaloptions: {
      concurrent?: boolean;
      exitOnError?: boolean;
      context?: T;
      rendererOptions?: any;
  }
Returns Promise<T>
- Defined in logger.ts:441

createTaskList

createTaskList<T = any>(
tasks: ListrTask<T, any, any>[],
options?: { concurrent?: boolean; exitOnError?: boolean; context?: T },
): Listr<T, typeof DevLogrRenderer>
Create a task list with the logger's prefix integration
Type Parameters
- T = any
Parameters
- tasks: ListrTask<T, any, any>[]
- Optionaloptions: { concurrent?: boolean; exitOnError?: boolean; context?: T }
Returns Listr<T, typeof DevLogrRenderer>
- Defined in logger.ts:506

runConcurrentTasks

runConcurrentTasks<T = any>(
    title: string,
    tasks: ListrTask<T, any, any>[],
    context?: T,
): Promise<T>
Execute concurrent tasks with proper logging
Type Parameters
- T = any
Parameters
- title: string
- tasks: ListrTask<T, any, any>[]
- Optionalcontext: T
Returns Promise<T>
- Defined in logger.ts:532

runSequentialTasks

runSequentialTasks<T = any>(
    title: string,
    tasks: ListrTask<T, any, any>[],
    context?: T,
): Promise<T>
Execute sequential tasks with proper logging
Type Parameters
- T = any
Parameters
- title: string
- tasks: ListrTask<T, any, any>[]
- Optionalcontext: T
Returns Promise<T>
- Defined in logger.ts:543

spacer

spacer(): void
Returns void
- Defined in logger.ts:555

separator

separator(title?: string): void
Parameters
- Optionaltitle: string
Returns void
- Defined in logger.ts:561

Class Logger

Example: Basic Usage

Example: Spinner Usage

Example: Task Management

Index

Constructors

Methods

Constructors

constructor

Parameters

Returns Logger

Methods

StaticsetLevel

Parameters

Returns void

StaticresetLevel

Returns void

info

Parameters

Returns void

error

Parameters

Returns void

warning

Parameters

Returns void

warn

Parameters

Returns void

debug

Parameters

Returns void

trace

Parameters

Returns void

success

Parameters

Returns void

title

Parameters

Returns void

task

Parameters

Returns void

plain

Parameters

Returns void

startSpinner

Parameters

Returns void

Example

Example: With custom options

updateSpinnerText

Parameters

Returns void

stopSpinner

Returns void

completeSpinner

Parameters

Returns void

completeSpinnerWithSuccess

Parameters

Returns void

completeSpinnerWithError

Parameters

Returns void

completeSpinnerWithWarning

Parameters

Returns void

completeSpinnerWithInfo

Parameters

Returns void

succeedSpinner

Parameters

Returns void

Example

failSpinner

Parameters

Returns void

warnSpinner

`Static`setLevel

`Static`resetLevel