144 lines
5.1 KiB
Markdown
144 lines
5.1 KiB
Markdown
# log4js-node [](http://travis-ci.org/nomiddlename/log4js-node)
|
|
|
|
|
|
This is a conversion of the [log4js](http://log4js.berlios.de/index.html)
|
|
framework to work with [node](http://nodejs.org). I've mainly stripped out the browser-specific code and tidied up some of the javascript.
|
|
|
|
Out of the box it supports the following features:
|
|
|
|
* coloured console logging
|
|
* replacement of node's console.log functions (optional)
|
|
* file appender, with log rolling based on file size
|
|
* SMTP appender
|
|
* GELF appender
|
|
* hook.io appender
|
|
* multiprocess appender (useful when you've got worker processes)
|
|
* a logger for connect/express servers
|
|
* configurable log message layout/patterns
|
|
* different log levels for different log categories (make some parts of your app log as DEBUG, others only ERRORS, etc.)
|
|
|
|
NOTE: from log4js 0.5 onwards you'll need to explicitly enable replacement of node's console.log functions. Do this either by calling `log4js.replaceConsole()` or configuring with an object or json file like this:
|
|
|
|
```javascript
|
|
{
|
|
appenders: [
|
|
{ type: "console" }
|
|
],
|
|
replaceConsole: true
|
|
}
|
|
```
|
|
|
|
## installation
|
|
|
|
npm install log4js
|
|
|
|
|
|
## usage
|
|
|
|
Minimalist version:
|
|
```javascript
|
|
var log4js = require('log4js');
|
|
var logger = log4js.getLogger();
|
|
logger.debug("Some debug messages");
|
|
```
|
|
By default, log4js outputs to stdout with the coloured layout (thanks to [masylum](http://github.com/masylum)), so for the above you would see:
|
|
```bash
|
|
[2010-01-17 11:43:37.987] [DEBUG] [default] - Some debug messages
|
|
```
|
|
See example.js for a full example, but here's a snippet (also in fromreadme.js):
|
|
```javascript
|
|
var log4js = require('log4js');
|
|
//console log is loaded by default, so you won't normally need to do this
|
|
//log4js.loadAppender('console');
|
|
log4js.loadAppender('file');
|
|
//log4js.addAppender(log4js.appenders.console());
|
|
log4js.addAppender(log4js.appenders.file('logs/cheese.log'), 'cheese');
|
|
|
|
var logger = log4js.getLogger('cheese');
|
|
logger.setLevel('ERROR');
|
|
|
|
logger.trace('Entering cheese testing');
|
|
logger.debug('Got cheese.');
|
|
logger.info('Cheese is Gouda.');
|
|
logger.warn('Cheese is quite smelly.');
|
|
logger.error('Cheese is too ripe!');
|
|
logger.fatal('Cheese was breeding ground for listeria.');
|
|
```
|
|
Output:
|
|
```bash
|
|
[2010-01-17 11:43:37.987] [ERROR] cheese - Cheese is too ripe!
|
|
[2010-01-17 11:43:37.990] [FATAL] cheese - Cheese was breeding ground for listeria.
|
|
```
|
|
The first 5 lines of the code above could also be written as:
|
|
```javascript
|
|
var log4js = require('log4js');
|
|
log4js.configure({
|
|
appenders: [
|
|
{ type: 'console' },
|
|
{ type: 'file', filename: 'logs/cheese.log', category: 'cheese' }
|
|
]
|
|
});
|
|
```
|
|
|
|
## configuration
|
|
|
|
You can configure the appenders and log levels manually (as above), or provide a
|
|
configuration file (`log4js.configure('path/to/file.json')`), or a configuration object. The
|
|
configuration file location may also be specified via the environment variable
|
|
LOG4JS_CONFIG (`export LOG4JS_CONFIG=path/to/file.json`).
|
|
An example file can be found in `test/log4js.json`. An example config file with log rolling is in `test/with-log-rolling.json`.
|
|
By default, the configuration file is checked for changes every 60 seconds, and if changed, reloaded. This allows changes to logging levels to occur without restarting the application.
|
|
|
|
To turn off configuration file change checking, configure with:
|
|
|
|
```javascript
|
|
var log4js = require('log4js');
|
|
log4js.configure('my_log4js_configuration.json', {});
|
|
```
|
|
To specify a different period:
|
|
|
|
```javascript
|
|
log4js.configure('file.json', { reloadSecs: 300 });
|
|
```
|
|
For FileAppender you can also pass the path to the log directory as an option where all your log files would be stored.
|
|
|
|
```javascript
|
|
log4js.configure('my_log4js_configuration.json', { cwd: '/absolute/path/to/log/dir' });
|
|
```
|
|
If you have already defined an absolute path for one of the FileAppenders in the configuration file, you could add a "absolute": true to the particular FileAppender to override the cwd option passed. Here is an example configuration file:
|
|
```json
|
|
#### my_log4js_configuration.json ####
|
|
{
|
|
"appenders": [
|
|
{
|
|
"type": "file",
|
|
"filename": "relative/path/to/log_file.log",
|
|
"maxLogSize": 20480,
|
|
"backups": 3,
|
|
"category": "relative-logger"
|
|
},
|
|
{
|
|
"type": "file",
|
|
"absolute": true,
|
|
"filename": "/absolute/path/to/log_file.log",
|
|
"maxLogSize": 20480,
|
|
"backups": 10,
|
|
"category": "absolute-logger"
|
|
}
|
|
]
|
|
}
|
|
```
|
|
Documentation for most of the core appenders can be found on the [wiki](https://github.com/nomiddlename/log4js-node/wiki/Appenders), otherwise take a look at the tests and the examples.
|
|
|
|
## Documentation
|
|
See the [wiki](https://github.com/nomiddlename/log4js-node/wiki). Improve the [wiki](https://github.com/nomiddlename/log4js-node/wiki), please.
|
|
|
|
## Contributing
|
|
Contributions welcome, but take a look at the [rules](https://github.com/nomiddlename/log4js-node/wiki/Contributing) first.
|
|
|
|
## License
|
|
|
|
The original log4js was distributed under the Apache 2.0 License, and so is this. I've tried to
|
|
keep the original copyright and author credits in place, except in sections that I have rewritten
|
|
extensively.
|