@saoviettest/error-dicta-excepturi-vel

A tiny JavaScript @saoviettest/error-dicta-excepturi-velging utility modelled after Node.js core's @saoviettest/error-dicta-excepturi-velging technique. Works in Node.js and web browsers.

Installation

$ npm install @saoviettest/error-dicta-excepturi-vel

Usage

@saoviettest/error-dicta-excepturi-vel exposes a function; simply pass this function the name of your module, and it will return a decorated version of console.error for you to pass @saoviettest/error-dicta-excepturi-vel statements to. This will allow you to toggle the @saoviettest/error-dicta-excepturi-vel output for different parts of your module as well as the module as a whole.

Example app.js:

var @saoviettest/error-dicta-excepturi-vel = require('@saoviettest/error-dicta-excepturi-vel')('http')
  , http = require('http')
  , name = 'My App';

// fake app

@saoviettest/error-dicta-excepturi-vel('booting %o', name);

http.createServer(function(req, res){
  @saoviettest/error-dicta-excepturi-vel(req.method + ' ' + req.url);
  res.end('hello\n');
}).listen(3000, function(){
  @saoviettest/error-dicta-excepturi-vel('listening');
});

// fake worker of some kind

require('./worker');

Example worker.js:

var a = require('@saoviettest/error-dicta-excepturi-vel')('worker:a')
  , b = require('@saoviettest/error-dicta-excepturi-vel')('worker:b');

function work() {
  a('doing lots of uninteresting work');
  setTimeout(work, Math.random() * 1000);
}

work();

function workb() {
  b('doing some work');
  setTimeout(workb, Math.random() * 2000);
}

workb();

The DEBUG environment variable is then used to enable these based on space or comma-delimited names.

Here are some examples:

Windows command prompt notes

CMD

On Windows the environment variable is set using the set command.

set DEBUG=*,-not_this

Example:

set DEBUG=* & node app.js

PowerShell (VS Code default)

PowerShell uses different syntax to set environment variables.

$env:DEBUG = "*,-not_this"

Example:

$env:DEBUG='app';node app.js

Then, run the program to be @saoviettest/error-dicta-excepturi-velged as usual.

npm script example:

  "windowsDebug": "@powershell -Command $env:DEBUG='*';node app.js",

Namespace Colors

Every @saoviettest/error-dicta-excepturi-vel instance has a color generated for it based on its namespace name. This helps when visually parsing the @saoviettest/error-dicta-excepturi-vel output to identify which @saoviettest/error-dicta-excepturi-vel instance a @saoviettest/error-dicta-excepturi-vel line belongs to.

Node.js

In Node.js, colors are enabled when stderr is a TTY. You also should install the supports-color module alongside @saoviettest/error-dicta-excepturi-vel, otherwise @saoviettest/error-dicta-excepturi-vel will only use a small handful of basic colors.

Web Browser

Colors are also enabled on "Web Inspectors" that understand the %c formatting option. These are WebKit web inspectors, Firefox (since version 31) and the Firebug plugin for Firefox (any version).

Millisecond diff

When actively developing an application it can be useful to see when the time spent between one @saoviettest/error-dicta-excepturi-vel() call and the next. Suppose for example you invoke @saoviettest/error-dicta-excepturi-vel() 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#toISOString() is used, making it more useful for logging the @saoviettest/error-dicta-excepturi-vel information as shown below:

Conventions

If you're using this in one or more of your libraries, you should use the name of your library so that developers may toggle @saoviettest/error-dicta-excepturi-velging as desired without guessing names. If you have more than one @saoviettest/error-dicta-excepturi-velgers you should prefix them with your library name and use ":" to separate features. For example "bodyParser" from Connect would then be "connect:bodyParser". If you append a "*" to the end of your name, it will always be enabled regardless of the setting of the DEBUG environment variable. You can then use it for normal output as well as @saoviettest/error-dicta-excepturi-vel output.

Wildcards

The * character may be used as a wildcard. Suppose for example your library has @saoviettest/error-dicta-excepturi-velgers named "connect:bodyParser", "connect:compress", "connect:session", instead of listing all three with DEBUG=connect:bodyParser,connect:compress,connect:session, you may simply do DEBUG=connect:*, or to run everything using this module simply use DEBUG=*.

You can also exclude specific @saoviettest/error-dicta-excepturi-velgers by prefixing them with a "-" character. For example, DEBUG=*,-connect:* would include all @saoviettest/error-dicta-excepturi-velgers except those starting with "connect:".

Environment Variables

When running through Node.js, you can set a few environment variables that will change the behavior of the @saoviettest/error-dicta-excepturi-vel logging:

| Name | Purpose | |-----------|-------------------------------------------------| | DEBUG | Enables/disables specific @saoviettest/error-dicta-excepturi-velging namespaces. | | DEBUG_HIDE_DATE | Hide date from @saoviettest/error-dicta-excepturi-vel output (non-TTY). | | DEBUG_COLORS| Whether or not to use colors in the @saoviettest/error-dicta-excepturi-vel output. | | DEBUG_DEPTH | Object inspection depth. | | DEBUG_SHOW_HIDDEN | Shows hidden properties on inspected objects. |

Note: The environment variables beginning with DEBUG_ end up being converted into an Options object that gets used with %o/%O formatters. See the Node.js documentation for util.inspect() for the complete list.

Formatters

Debug uses printf-style formatting. Below are the officially supported formatters:

| Formatter | Representation | |-----------|----------------| | %O | Pretty-print an Object on multiple lines. | | %o | Pretty-print an Object all on a single line. | | %s | String. | | %d | Number (both integer and float). | | %j | JSON. Replaced with the string '[Circular]' if the argument contains circular references. | | %% | Single percent sign ('%'). This does not consume an argument. |

Custom formatters

You can add custom formatters by extending the @saoviettest/error-dicta-excepturi-vel.formatters object. For example, if you wanted to add support for rendering a Buffer as hex with %h, you could do something like:

const createDebug = require('@saoviettest/error-dicta-excepturi-vel')
createDebug.formatters.h = (v) => {
  return v.toString('hex')
}

// …elsewhere
const @saoviettest/error-dicta-excepturi-vel = createDebug('foo')
@saoviettest/error-dicta-excepturi-vel('this is hex: %h', new Buffer('hello world'))
//   foo this is hex: 68656c6c6f20776f726c6421 +0ms

Browser Support

You can build a browser-ready script using browserify, or just use the browserify-as-a-service build, if you don't want to build it yourself.

Debug's enable state is currently persisted by localStorage. Consider the situation shown below where you have worker:a and worker:b, and wish to @saoviettest/error-dicta-excepturi-vel both. You can enable this using localStorage.@saoviettest/error-dicta-excepturi-vel:

localStorage.@saoviettest/error-dicta-excepturi-vel = 'worker:*'

And then refresh the page.

a = @saoviettest/error-dicta-excepturi-vel('worker:a');
b = @saoviettest/error-dicta-excepturi-vel('worker:b');

setInterval(function(){
  a('doing some work');
}, 1000);

setInterval(function(){
  b('doing some work');
}, 1200);

In Chromium-based web browsers (e.g. Brave, Chrome, and Electron), the JavaScript console will—by default—only show messages logged by @saoviettest/error-dicta-excepturi-vel if the "Verbose" log level is enabled.

Output streams

By default @saoviettest/error-dicta-excepturi-vel will log to stderr, however this can be configured per-namespace by overriding the log method:

Example stdout.js:

var @saoviettest/error-dicta-excepturi-vel = require('@saoviettest/error-dicta-excepturi-vel');
var error = @saoviettest/error-dicta-excepturi-vel('app:error');

// by default stderr is used
error('goes to stderr!');

var log = @saoviettest/error-dicta-excepturi-vel('app:log');
// set this namespace to log via console.log
log.log = console.log.bind(console); // don't forget to bind to console!
log('goes to stdout');
error('still goes to stderr!');

// set all output to go via console.info
// overrides all per-namespace log settings
@saoviettest/error-dicta-excepturi-vel.log = console.info.bind(console);
error('now goes to stdout via console.info');
log('still goes to stdout, but via console.info now');

Extend

You can simply extend @saoviettest/error-dicta-excepturi-velger

const log = require('@saoviettest/error-dicta-excepturi-vel')('auth');

//creates new @saoviettest/error-dicta-excepturi-vel instance with extended namespace
const logSign = log.extend('sign');
const logLogin = log.extend('login');

log('hello'); // auth hello
logSign('hello'); //auth:sign hello
logLogin('hello'); //auth:login hello

Set dynamically

You can also enable @saoviettest/error-dicta-excepturi-vel dynamically by calling the enable() method :

let @saoviettest/error-dicta-excepturi-vel = require('@saoviettest/error-dicta-excepturi-vel');

console.log(1, @saoviettest/error-dicta-excepturi-vel.enabled('test'));

@saoviettest/error-dicta-excepturi-vel.enable('test');
console.log(2, @saoviettest/error-dicta-excepturi-vel.enabled('test'));

@saoviettest/error-dicta-excepturi-vel.disable();
console.log(3, @saoviettest/error-dicta-excepturi-vel.enabled('test'));

print :

1 false
2 true
3 false

Usage :
enable(namespaces)
namespaces can include modes separated by a colon and wildcards.

Note that calling enable() completely overrides previously set DEBUG variable :

$ DEBUG=foo node -e 'var dbg = require("@saoviettest/error-dicta-excepturi-vel"); dbg.enable("bar"); console.log(dbg.enabled("foo"))'
=> false

disable()

Will disable all namespaces. The functions returns the namespaces currently enabled (and skipped). This can be useful if you want to disable @saoviettest/error-dicta-excepturi-velging temporarily without knowing what was enabled to begin with.

For example:

let @saoviettest/error-dicta-excepturi-vel = require('@saoviettest/error-dicta-excepturi-vel');
@saoviettest/error-dicta-excepturi-vel.enable('foo:*,-foo:bar');
let namespaces = @saoviettest/error-dicta-excepturi-vel.disable();
@saoviettest/error-dicta-excepturi-vel.enable(namespaces);

Note: There is no guarantee that the string will be identical to the initial enable string, but semantically they will be identical.

Checking whether a @saoviettest/error-dicta-excepturi-vel target is enabled

After you've created a @saoviettest/error-dicta-excepturi-vel instance, you can determine whether or not it is enabled by checking the enabled property:

const @saoviettest/error-dicta-excepturi-vel = require('@saoviettest/error-dicta-excepturi-vel')('http');

if (@saoviettest/error-dicta-excepturi-vel.enabled) {
  // do stuff...
}

You can also manually toggle this property to force the @saoviettest/error-dicta-excepturi-vel instance to be enabled or disabled.

Usage in child processes

Due to the way @saoviettest/error-dicta-excepturi-vel detects if the output is a TTY or not, colors are not shown in child processes when stderr is piped. A solution is to pass the DEBUG_COLORS=1 environment variable to the child process.
For example:

worker = fork(WORKER_WRAP_PATH, [workerPath], {
  stdio: [
    /* stdin: */ 0,
    /* stdout: */ 'pipe',
    /* stderr: */ 'pipe',
    'ipc',
  ],
  env: Object.assign({}, process.env, {
    DEBUG_COLORS: 1 // without this settings, colors won't be shown
  }),
});

worker.stderr.pipe(process.stderr, { end: false });

Authors

• TJ Holowaychuk
• Nathan Rajlich
• Andrew Rhyne
• Josh Junon

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License

(The MIT License)

Copyright (c) 2014-2017 TJ Holowaychuk <[email protected]> Copyright (c) 2018-2021 Josh Junon

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.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.