
Security News
Create React App Officially Deprecated Amid React 19 Compatibility Issues
Create React App is officially deprecated due to React 19 issues and lack of maintenance—developers should switch to Vite or other modern alternatives.
debug-logger
Advanced tools
A thin wrapper for visionmedia/debug logger, adding levels and colored output.
visionmedia/debug is a ubitiquous logging library with 1000+ dependants. Given how widespread it is and the convenience of namespaces it is a great logger for library modules.
debug-logger
is a convenience wrapper around debug
that adds level based coloured output. Each instance of debug-logger
will lazily instantiate several instances of debug
such as namespace:info
, namespace:warn
, namespace:error
, etc. All these are configurable. debug-logger
has no dependencies besides debug
.
debug-logger
uses the same syntax as node.js console so you can use it as drop in replacement.
Check and run examples/console.parity.js for more details.
At AppsCot we use debug-logger
in waterline-orientdb.
npm install debug-logger -S
var log = require('debug-logger')('myapp');
log.trace("I'm a trace output");
log.debug("I'm a debug output");
log.log("I'm a log output");
log.info("I'm an info output");
log.warn("I'm a warn output");
log.error("I'm an error output");
var err = new Error('error message');
err.stack = 'the stack\nline2\nline3';
log.error('Something failed:', err);
var obj = {
anumber : 1234,
astring : 'str',
adate : new Date(),
aboolean : true
};
log.info("let's inspect 'obj'", obj);
debug
instances and enabled propertylog.debug.logger()("the debug instance of debug, using 'myapp:debug' namespace");
var debug = debugLogger.debug('myapp:visionmedia');
debug('Nothing tastes better than the original!');
if (log.debug.enabled()) {
// This only runs if environment variable DEBUG includes "myapp:debug" namespace
log.debug("Debug is enabled");
}
Full util.inspect
options available at nodejs.org.
var debugLogger = require('debug-logger');
debugLogger.inspectOptions = {
colors : true
};
log.info('By enabling colors we get this nice colored example:', {
anumber : 1234,
astring : 'str',
adate : new Date(),
aboolean : true
});
debugLogger.levels.error.color = debugLogger.colors.magenta;
debugLogger.levels.error.prefix = 'ERROR ';
var customColorLog = debugLogger('myapp');
customColorLog.error("I'm a 'magenta' error output");
debugLogger.levels.silly = {
color : debugLogger.colors.magenta,
prefix : 'SILLY ',
namespaceSuffix : ':silly'
};
var sillyLog = debugLogger('myapp');
sillyLog.silly("I'm a silly output");
log.log("Multiple", "arguments", "including", "objects:", { obj: 'obj'}, "makes life easier");
log.warn("util.format style string: %s, number: %d and json: %j.", "foo", 13, { obj: 'json'});
log.time('100-elements');
for (var i = 0; i < 100; i++) {
;
}
log.timeEnd('100-elements');
log.time('setTimeout');
setTimeout(function(){
var diff = log.timeEnd('setTimeout', 'debug');
log.trace('log.timeEnd returns diff so it can be reused:', diff);
}, 262);
log.dir({ foo: { bar: 1 } });
log.dir({ foo: { bar: 1 } }, { depth: 0 }, 'warn');
log.assert(1 == 0);
// More elaborate example
var log = require('..').config({
levels: {
fatal: {
color : 5, //magenta
prefix : '',
namespaceSuffix : ':fatal',
level : 6
}
}
})('myapp');
log.assert(1 == 0, 'testing %s %d', 'log.assert', 666, 'fatal');
By default trace, debug, log and info output to stdout while warn and error output to stderr. This is configurable, example:
var log = require('debug')('myapp');
log.trace("goes to stdout!");
log.debug("goes to stdout!");
log.log("goes to stdout!");
log.info("goes to stdout!");
log.warn("goes to stderr");
log.error("goes to stderr");
// outputting only to stdout
var stdout = require('debug').config({ levels: { warn: { fd: 1 }, error: { fd: 1 } } })('stdoutapp');
stdout.warn("goes to stdout!");
stdout.error("goes to stdout!");
export DEBUG_LEVEL=info
Only info level and above logs will be outputted.
More examples in the examples folder.
Assuming log is an instance of debug-logger (var log = require('debug-logger')('myapp');
).
log.trace([data][, ...])
log.debug([data][, ...])
log.log([data][, ...])
log.info([data][, ...])
log.warn([data][, ...])
log.error([data][, ...])
Prints the data prepended by log level. If the terminal supports colors, each level will have a specific color. If an Error is provided, the toString() and call stack will be outputted. If an Object is provided the toString() and util.inspect() will be outputted. Example:
myapp:debug I'm a debug output +0ms
myapp:info I'm an info output +1ms
This function can take multiple arguments in a printf()-like way, if formatting elements are not found in the first string then util.inspect is used on each argument.
log([message][, ...])
Outputs the message using the root/default debug
instance, without the level suffix. Example:
myapp I'm a root/default debug instance output +0ms
log[level].logger()
Returns the default debug
instance used by level
.
log[level].enabled()
Boolean indicating if level
's logger is enabled.
log.time(label)
Mark a time.
log.timeEnd(label[, level])
Finish timer, record output. level
will determine the logger used to output the result (defaults to 'log').
Return duration in ms.
log.dir(obj[, options][, level])
Uses util.inspect on obj and prints resulting string to the appropriate logger. This function bypasses any custom inspect() function on obj. An optional options object may be passed that alters certain aspects of the formatted string.
level
will determine the logger used to output the result (defaults to 'log').
log.assert(value[, message][, ...][, level])
Similar to console.assert().
Additionally it outputs the error using the appropriate logger set by level
(defaults to 'error').
.config(obj)
Configures debug-logger. Returns debug-logger
to allow chaining operations.
.debug
Returns visionmedia/debug module.
FAQs
A wrapper for visionmedia/debug logger, adding levels and colored output
The npm package debug-logger receives a total of 3,314 weekly downloads. As such, debug-logger popularity was classified as popular.
We found that debug-logger demonstrated a not healthy version release cadence and project activity because the last version was released a year ago. It has 1 open source maintainer collaborating on the project.
Did you know?
Socket for GitHub automatically highlights issues in each pull request and monitors the health of all your open source dependencies. Discover the contents of your packages and block harmful activity before you install or update your dependencies.
Security News
Create React App is officially deprecated due to React 19 issues and lack of maintenance—developers should switch to Vite or other modern alternatives.
Security News
Oracle seeks to dismiss fraud claims in the JavaScript trademark dispute, delaying the case and avoiding questions about its right to the name.
Security News
The Linux Foundation is warning open source developers that compliance with global sanctions is mandatory, highlighting legal risks and restrictions on contributions.