2016-03-22 18:11:11 +01:00

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---
title: Logging
---
Strapi comes with a simple and useful built-in logger. Its usage is purposely very similar to `console.log()`, but with a handful of extra features; namely support for multiple log levels with colorized, prefixed console output.
## Configuration
Configuration:
- Key: `logger`
- Environment: `development`
- Location: `./config/environments/development/server.json`
- Type: `boolean`
Example:
```js
{
"logger": true
}
```
Notes:
- Set to `false` to disable the lifecyle and request logs.
## Usage
The logger is accessible through the `strapi` object directly with `strapi.log`.
You can work with this logger in the same way that you work with the default logger:
```js
strapi.log.info('Logs work!');
```
### Logging with Metadata
In addition to logging string messages, the logger will also optionally log additional JSON metadata objects. Adding metadata is simple:
```js
strapi.log.info('Test log message', {
anything: 'This is metadata'
});
```
### String interpolation
The log method provides the same string interpolation methods like `util.format`.
This allows for the following log messages.
```js
strapi.log.info('test message %s', 'my string');
// => info: test message my string
```
```js
strapi.log.info('test message %d', 123);
// => info: test message 123
```
```js
strapi.log.info('test message %j', {
number: 123
}, {});
// => info: test message {"number":123}
// => meta = {}
```
```js
strapi.log.info('test message %s, %s', 'first', 'second', {
number: 123
});
// => info: test message first, second
// => meta = {number: 123}
```
```js
strapi.log.info('test message', 'first', 'second', {
number: 123
});
// => info: test message first second
// => meta = {number: 123}
```
```js
strapi.log.info('test message %s, %s', 'first', 'second', {
number: 123
}, function() {});
// => info: test message first, second
// => meta = {number: 123}
// => callback = function() {}
```
```js
strapi.log.info('test message', 'first', 'second', {
number: 123
}, function() {});
// => info: test message first second
// => meta = {number: 123}
// => callback = function() {}
```
### Logging levels
Setting the level for your logging message can be accomplished by using the level specified methods defined.
```js
strapi.log.debug('This is a debug log');
strapi.log.info('This is an info log');
strapi.log.warn('This is a warning log');
strapi.log.error('This is an error log');
```