# NestJS Pretty Logger

![1126201123](https://cdn.jsdelivr.net/gh/Innei/fancy-2023@main/2023/1126201123.png)

## Introduction

"NestJS Pretty Logger" is a versatile and visually appealing global Logger module for NestJS applications. This module extends the functionality of the default NestJS logger by utilizing the [consola](https://github.com/unjs/consola) library for enhanced aesthetics and includes features like file redirection and real-time logging capabilities.

## Features

- **Aesthetic and Functional Logging**: Integrates [consola](https://github.com/unjs/consola) for an enhanced logging experience.
- **Log File Redirection**: Ability to redirect `stdout` to files, allowing for organized log management.
- **App-Wide Logging Coverage**: Capable of covering the entire application's console and `stdout.write` functionalities.
- **Real-Time Logging Support**: Provides the `onData()` hook for real-time logging implementations, such as custom log recorders or WebSocket real-time log streaming.

## Installation

To install, run the following command:

```bash
npm i nestjs-pretty-logger
```

## Usage

### Basic Setup

In your `main.ts`:

```typescript
// main.ts
import { Logger } from 'nestjs-pretty-logger'

import { NestFactory } from '@nestjs/core'

import { AppModule } from './app.module'

async function bootstrap() {
  const app = await NestFactory.create(AppModule)
  app.useLogger(app.get(Logger))
  await app.listen(3000)
}
bootstrap()
```

In your `app.module.ts`:

```typescript
// app.module.ts
import { LoggerModule } from 'nestjs-pretty-logger'

import { Module } from '@nestjs/common'

import { AppController, AppService } from './app.controller'

@Module({
  imports: [LoggerModule],
  controllers: [AppController],
  providers: [AppService],
})
export class AppModule {}
```

### Custom Logger Configuration

Configure and utilize advanced features:

```typescript
// Custom Logger Setup
import path from 'path'
import { createLogger, Logger } from 'nestjs-pretty-logger'

import { NestFactory } from '@nestjs/core'

import { AppModule } from './app.module'

const customLogger = createLogger({
  writeToFile: {
    loggerDir: path.resolve(__dirname, './logs'),
  },
})

// Wrap all console and stdout.write with customLogger
customLogger.wrapAll()

// Implement onData hook for real-time logging or custom actions
customLogger.onData((data) => {
  // Your custom implementation here
})

// Only error log
customLogger.onStdErr((data) => {
  // Your custom implementation here
})

// Only non-error log
customLogger.onStdOut((data) => {
  // Your custom implementation here
})

async function bootstrap() {
  const app = await NestFactory.create(AppModule)
  Logger.setLoggerInstance(customLogger)
  app.useLogger(app.get(Logger))
  await app.listen(3000)
}
bootstrap()
```

**Note**: After invoking `wrapAll()`, avoid using `console.log` or similar stdout functions within `onData()` to prevent potential infinite loops.

## Configuration Options

The `createLogger` method includes the `FileReporterConfig` interface for file redirection:

```typescript
interface FileReporterConfig {
  loggerDir: string // Required: Log file directory
  stdoutFileFormat?: string // Optional: Default 'stdout_%d%.log'
  stderrFileFormat?: string // Optional: Default 'error.log'
  cron?: string // Optional: Default '0 0 * * *' for daily log rotation
}
```

This configuration is crucial for directing `stdout` to log files, with `loggerDir` being mandatory for specifying the log directory. The other parameters are optional, offering defaults for file formats and log rotation, which can be changed through the `cron` setting.

## Contributions

Contributions to "NestJS Pretty Logger" are highly appreciated. Whether it's through pull requests or issue discussions, your feedback and contributions are valuable to the project.

## License

2023 © Innei, MIT License.

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