loglevel-prefix-persist
loglevel plugin - Support for the following:
- (Almost) Isomorphic - passes single log config that can be used on both client and server
- can be used by client or server alone
- client & server log message prefix with [your/module-name]
- client & server log persistence
- additional datetime information, text color to server log
Uses
#Usage
Assuming the following simple config
var logCfg = {
"level":{
"production": "warn",
"development": "info"
},
"persist":"error",
"max":2
}
On server side, initialize plugin in server.js
var loglevel = require('loglevel');
var logger = require('loglevel-prefix-persist/server')
var log = logger(process.env.NODE_ENV, loglevel, logCfg);
var app = express();
app
.use(bodyParser.urlencoded({ extended: false }))
.use(bodyParser.json())
//...
if (log.writer) {
// if client log persistence is enabled, this will accept and writes logs coming from client side
app.use(log.writer);
}
On client side, initialize plugin in client.js entry
var loglevel = require('loglevel');
var logger = require('loglevel-prefix-persist/client');
var log = logger('development', loglevel, logCfg);
All together (for both client and server)
// namespacing modules
var log = require('loglevel').getLogger("my/module-name");
// start logging
log.debug('Debug will not show')
log.info('Info will show under development, but not in production','config',logCfg)
log.warn('Warn will always show')
log.error('Error will always show')
#Result
server
client
#Config
- Default environment is 'development'
- Default log level is 'info'
- Default persistence for server is same as log level
- Default persistence for client is disabled
- If persistence is turned on and max is not set, old files will not be cleaned up
Config examples:
// log level='warn', server persistence only (at 'warn'), log daily forever
var logCfg = {
"level":"warn"
}
// log level for client+server, no persistence
var logCfg = {
"level": {"server":"info", "client":"warn"}, // regardless of environment
"persist":false
}
// log level for production+development, persist for level='error', max 2 days log
var logCfg = {
"level":{
"production": "warn",
"development": "info"
},
"persist":"error",
"max":2
}
// cfg for production+developement, client+server
var logCfg = {
"level":{
"production": {"server":"info", "client":"warn"},
"development": "debug"
},
"persist":{
"client":"error", // only persist client level='error'
"server":true // persist server 'debug' in development, 'info' in production
},
"max":2
}
