small node.js debugging utility modeled after node core's debugging technique with log levels and output mechanisms.
$ npm install seismograph
With seismograph you simply invoke the exported function to generate your log function, passing it a name which will determine if a noop function is returned, or a decorated console.error, so all of the console format string goodies you're used to work fine. A unique color is selected per-function for visibility.
var log = require('seismograph')('http');
var http = require('http');
var name = 'My App';
// fake app
log.info('booting %s', name);
log.info(req.method + ' ' + req.url);
// fake worker of some kindrequire('./worker');
var log = require('seismograph')('worker');
log.debug('doing some work');
The DEBUG environment variable is then used to prioritize these based on space or comma-delimited names.
When actively developing an application it can be useful to see when the time spent between one log call and the next. Suppose for example you invoke log.info() before requesting a resource, and after as well, the "+NNNms" will show you how much time was spent between calls.
When stdout is not a TTY, Date#toUTCString() is used by default, making it more useful for logging the debug information.
The * character may be used as a wildcard. Suppose for example your application has debug logs named "worker:login", "worker:logout", "worker:credit", instead of listing all three with DEBUG=worker:login,worker:logout,worker:credit, you may simply do DEBUG=worker:*, or to run everything using this module simply use DEBUG=*.
You can also exclude specific debuggers by prefixing them with a "-" character. For example, DEBUG='* -worker:*' would include all debuggers except those starting with "worker:".
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
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