# log4js-json-layout

> Provides a slim and easy to use json-layout for log4js-node

Latest version **2.2.3** (published 2021-04-12) · ISC license · 0 weekly downloads

## Install

```sh
npm install log4js-json-layout
pnpm add log4js-json-layout
yarn add log4js-json-layout
bun add log4js-json-layout
```

## Health

**Score 15/100 (F)** — status: abandoned.

Positive: no vulnerabilities.

Warnings: low downloads; no types; no esm support.

Negative: abandoned; low maintenance score.

## Facts

| | |
|---|---|
| Version | 2.2.3 |
| Published | 2021-04-12 |
| First published | 2016-05-08 |
| Weekly downloads | 0 |
| License | ISC |
| TypeScript types | none |
| Module format | CommonJS |
| Node | >=6 |
| Dependencies | 2 |
| Unpacked size | 17 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| GitHub stars | 17 |
| Author | Ido Schachter |
| Maintainers | id0sch |

## Links

- npm: https://www.npmjs.com/package/log4js-json-layout
- Repository: https://github.com/id0Sch/log4js-json-layout
- Homepage: https://github.com/id0Sch/log4js-json-layout#readme
- Issues: https://github.com/id0Sch/log4js-json-layout/issues
- npm.io page: https://npm.io/package/log4js-json-layout

## Dependencies (2)

- [colors](https://npm.io/package/colors.md) ^1.1.2
- [lodash](https://npm.io/package/lodash.md) ^4.17.4

## Recent versions

- 2.2.3 (latest) — 2021-04-12
- 2.2.2 — 2020-03-18
- 2.1.0 — 2017-08-29
- 2.0.0 — 2017-07-30
- 1.0.5 — 2016-09-04
- 1.0.4 — 2016-09-04
- 1.0.3 — 2016-08-16
- 1.0.2 — 2016-05-09
- 1.0.1 — 2016-05-08
- 1.0.0 — 2016-05-08

## README

# log4js-json-layout

A slim and easy to use JSON layout for [log4js-node](https://github.com/nomiddlename/log4js-node).

[![NPM](https://nodei.co/npm/log4js-json-layout.png?downloads=true&downloadRank=true&stars=true)](https://nodei.co/npm/log4js-json-layout/)

[![Build Status](https://travis-ci.org/id0Sch/log4js-json-layout.svg?branch=master)](https://travis-ci.org/id0Sch/log4js-json-layout)

## Installation

```bash
npm install log4js-json-layout --save
```

## Example Output

Output:

```json
{"startTime":"2017-07-27T00:01:05.175Z","categoryName":"/path/to/file/redis-client.js","level":"DEBUG","data":"Connection to Redis successful!"}
```

## Usage

Set the layout type to `json`.

Each log object contains the following properties:

- `startTime` - time in ISO 8601 format
- `categoryName` - specified when `log4js` is initialized
- `data` - if the log message is a string, otherwise omitted
- `level` - level in human readable format
- `source` - if provided, will be included

Additional properties can be specified as extra arguments of object type during invocation of log function. Static or constant properties can be specified using the `static` config option.

### Options

- `type` - string, always `json`
- `source` - optional string, just sets the property `source`. Example value: `development`
- `include` - array of properties to include in the log object
- `colors` - boolean; off by default. If set to true, colorizes the output using log4js default color scheme based on log level. Useful for development, do not use for storing logs
- `static` - object, name value pairs of this object are added to output 
- `dynamic` - object, where each value is a no-argument function that must return a string/number/boolean. The key and the function's return value are added to the output

### Example Config

```js
const log4js = require('log4js');
const jsonLayout = require('log4js-json-layout');

log4js.addLayout('json', jsonLayout);
```

Minimal:

```js
appenders = [{
  type: 'console',
  layout: {
    type: 'json',
  }
}];
```

More options:

```js
appenders = [{
  type: 'console',
  messageParam: 'msg',
  layout: {
    type: 'json',
    source: 'development',
    static: {
      appName: 'mysuperbapp'
    },
    dynamic: {
      transactionId: function() {
        return 'tx-id'; // string
      },
      isAdmin: function() {
        return 1>0; // boolean
      },
      countLogin: function() {
        return 20; // number
      }
    },
    include: ['startTime', 'categoryName'],
  }
}];

const logger = log4js.getLogger('info');

logger.info('Test log');
```

Output:
```json
{"startTime":"2017-07-27T00:01:05.175Z","categoryName":"/path/to/file/redis-client.js","level":"DEBUG","transactionId": "tx-id","isAdmin": true,"countLogin": 20,"data":"Test log",}
```

---
_Source: https://npm.io/package/log4js-json-layout · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._