npm install gracelog
var gracelog = require('gracelog');
var logger = gracelog.create();
logger.verbose('something not so important to log.');
logger.sys('sys message to log...');
logger.debug('debug message to log...');
logger.trace('logging message with stack trace.');
logger.table([1,2,3,4]);
logger.info('something important');
logger.error('some error');
logger.fatal('this is bad...');If you do not call this function, the module will be running in its default configurations.
"stackdriver": <bool> // logger.error will use stackdriver format: https://cloud.google.com/error-reporting/docs/formatting-error-messages
"rotationType": <string> // define log file rotation type [year|month|day|hour]. Default is day
"useTimestamp": <bool> // if given true, the logging time will be in Unix timestamp instead of the server time
"bufferSize": <int> // log data buffer size in memory (bytes),
"bufferFlushInterval": <int> // log data buffer auto flush interval in milliseconds,
"oneFile": <boolean> // if true, file logging will be combined to one file for all logging levels. default is false
"file": "<log directory path> or false"
"compress": true or false, // if true, objects will be printed as a single line output
"console": true or false,
"remote": <object> or null/false,
"color": true or false,
"showHidden": true or false, // show hidden properties of object
"depth": <integer> // recursive depth of object
"level": [
"verbose",
"sys",
"debug",
"trace",
"info",
"warn",
"error",
"fatal",
]
};
gracelog.config(configData); var logger = gracelog.create();
### Configurations for log levels
There are 8 log levels in log module:
`verbose, sys, debug, trace, info, warn, error, fatal`
Example:
var configData = { "console": true, "color": true, "level": [ "info", "warn", "error", "fatal" ] };
gracelog.confoig(configData);
The above configurations will enable `info`, `warn`, `error`, and `fatal`.
The same configurations can be done by:
var configData = { "console": true, "color": true, "level": ">= info" };
gracelog.config(configData);
***
### Buffering
Log module buffers log data in memory before outputting into file/remote/console.
The defualt buffer size is 8kb (8129 bytes) and default bufferFlushInterval is 5 seconds (5000 ms).
***
#### file
If the path to file is set, gracelog will log into files.
Log files are auto-rotated by YYYY/MM/DD.
`"file": "path to log file directory" or false/null`
#### remote
If the configurations for `remote` logging is provided, gracelog sends log data via UDP protocol.
**Configurations**
var gracelog = require('gracelog'); var configData = { remote: { host: 'localhost', port: 8000 } }; gracelog.config(configData);
#### console
If set to true, gracelog will send log to stdout/stderr stream of your application's process.
Log module uses console object of node.js. This is a blocking operation. It is better to turn this option off in production.
`"console": true or false`
#### color
If set to true, gracelog will color log text.
Each log level has different color.
`"color": true or false`
#### showHidden
If set to true, gracelog will log hidden properties of objects.
`"showHidden": true or false`
#### depth
Decides how far log module should recursively display objects.
`"depth": <integer>`
#### level
Log module has 6 log levels. If set to false, gracelog will ignored that level.
Each log level can be configured.
"level": ">= verbose"
Or
"level": [ "verbose", "sys", "debug", "info", "warn", "error", "fatal" ]
Or
"level": { "verbose": , "sys": , "debug": , "info": , "warn": , "error": , "fatal": }
***
## Events: *output*
gracelog.on('output', function (address, name, level, messageObj) { // address: IP address of the server // name: the name that was set on gracelog.create() // level: verbose, debug, info, warn, error, or fatal // messageObj: { message, timestamp } });
***
### .clean(callback [function])
Cleans up logging data.
Useful to invoke this function before exiting an application process.
### .setPrefix(prefix [string])
Sets a prefix for each logging.
### .forceFlush(callback [function])
Forcefully flushes all buffered log data and write immediately.
### .create(logName [*string])
Returns an instance of logger object.
If `logName` is not provided, it will default to the file name (full path) of script calling it.
### .isEnabled(levelName [string])
Returns Boolean. If given log level name is enabled, it returns true.
***
## Logger Object
### API: *createTable*
Creates a table data for logging from a javascript object.
var tableData = logger.createTable(sqlResult); logger.debug(tableData);
### API: *verbose*
<pre>
void verbose(mixed data, [...])
</pre>
### API: *sys*
<pre>
void sys(mixed data, [...])
</pre>
### API: *debug*
<pre>
void debug(mixed data, [...])
</pre>
### API: *table*
<pre>
void table(mixed data, [...])
</pre>
Outputs log at `debug` level and converts objects into tables.
Example:
var test = { one: { name: 'testOne', value: 1, language: '日本語', }, two: { name: 'testTwo<2>', language: 'こんにちは', ident: '02' }, three: { name: 'testThree<3>', value: 3, language: 'ありがとうございます', list: ['A', 'B', 'C'], map: { c: 'c', d: 'd' } }, five: { name: '魏民以夜光為怪石', language: 'chinese' }, six: { name: 'korean', value: -200, language: '해빛', list: [10, 20, 30] } }; logger.table(test);
The output of the above code would be:
**NOTE:** Spacing is off in this example, but the actual output would have correct spacing.
+---------+--------------------+-----------------------------------------+------------------------+--------+----------+-----------------+ | (index) | name | value | language | ident | list | map | +---------+--------------------+-----------------------------------------+------------------------+--------+----------+-----------------+ | one | "testOne" | 1 | "日本語" | | | | +---------+--------------------+-----------------------------------------+------------------------+--------+----------+-----------------+ | two | "testTwo<2>" | | "こんにちは" | "02" | | | +---------+--------------------+-----------------------------------------+------------------------+--------+----------+-----------------+ | three | "testThree<3>" | 3 | "ありがとうございます" | | A,B,C | [object Object] | +---------+--------------------+-----------------------------------------+------------------------+--------+----------+-----------------+ | five | "魏民以夜光為怪石" | | "chinese" | | | | +---------+--------------------+-----------------------------------------+------------------------+--------+----------+-----------------+ | six | "korean" | -200 | "해빛" | | 10,20,30 | | +---------+--------------------+-----------------------------------------+------------------------+--------+----------+-----------------+
### API: *trace*
`.trace()` outputs a stack trace for debugging.
### API: *info*
<pre>
void info(mixed data, [...])
</pre>
### API: *warn*
<pre>
void warn(mixed data, [...])
</pre>
### API: *warning*
Alias of warn
<pre>
void warning(mixed data, [...])
</pre>
### API: *error*
<pre>
void error(mixed data, [...])
</pre>
### API: *fatal*
<pre>
void fatal(mixed data, [...])
</pre>
***