debug-trace

debug-trace

This fork of console-trace adds the following features:

• work with callsite >= version 1.0.0
• work with https://github.com/visionmedia/debug (and print the caller of debug instead of console)
• provide an easy to override formatting function console.format e.g.:

  // overridable console string prefix formatting function
  console.format = function (c) {
    return c.getDate() + ": [" + c.filename + ":" + c.getLineNumber() + "] " + c.functionName;
  };

Available methods from V8 JavaScript stack trace API

• getThis: returns the value of this
• getTypeName: returns the type of this as a string. This is the name of the function stored in the constructor field of this, if available, otherwise the object's [[Class]] internal property.
• getFunction: returns the current function
• getFunctionName: returns the name of the current function, typically its name property. If a name property is not available an attempt will be made to try to infer a name from the function's context.
• getMethodName: returns the name of the property of this or one of its prototypes that holds the current function
• getFileName: if this function was defined in a script returns the name of the script
• getLineNumber: if this function was defined in a script returns the current line number
• getColumnNumber: if this function was defined in a script returns the current column number
• getEvalOrigin: if this function was created using a call to eval returns a CallSite object representing the location where eval was called
• isToplevel: is this a toplevel invocation, that is, is this the global object?
• isEval: does this call take place in code defined by a call to eval?
• isNative: is this call in native V8 code?
• isConstructor: is this a constructor call?

Additional method

• getDate(): actual date formatted like this: "2016-10-04 07:18:46.719"

Additional properties

• filename: getFileName without the base path: console.traceOptions.cwd
• method: console method name like log, error ect.
• functionName: call.getFunctionName() || 'anonymous'

Extends the native Node.JS console object to prefix logging functions with the CallSite information.

To read more about runtime stack trace introspection you can refer to this article.

Installation

$ npm install debug-trace

Syntax:

require('debug-trace')([options])

Available Options:

• always - (Boolean: defaults to false) always print the callsite info even without accessing methods from the t or traced getters.
• cwd - (String: defaults to process.cwd()) the path that will be stripped from the callsite info
• colors - (Boolean|Object: defaults to undefined) terminal colors support flag or a custom color object
• right - (Boolean: defaults to false) callsite alignment flag, when true prints infos on the right
• overwriteDebugLog - (Function: defaults to console.log) overwrites debug module log function, can be turned off with overwriteDebugLog: false
• patchOutput - (Boolean: defaults to true) monkey patches process.stdout.write and process.stderr.write with console.log and console.error in case it is called from debug (function with the name log)

Examples:

require('debug-trace')

You can add the t or traced getter to your calls to obtain a stacktrace:

console.t.log('a');
console.traced.log('a');

You can also make every console call trace:

require('debug-trace')({
  always: true,
})

...

console.log('a');     // tracing
console.error('a');   // tracing

You can align the callsite infos to the right

require('debug-trace')({
  always: true,
  right: true
})

...

console.log('a');     // tracing right
console.error('a');   // tracing right

You can change defaults colors too

require('./debug-trace')({
  always: true,
  colors: {
    warn: '35',
    info: '32'
  }
})

...

console.warn('a');    // magenta
console.info('a');    // green

To customize the string that's prefixed to the calls, override the console.traceFormat function.

Beyond console

If you have more sophisticated logging needs, or don't wish to extend console, I suggest you look at tracer.

Credits

I only added some functionality to the original console-trace:

• Guillermo Rauch
• Kilian Ciuffolo
• Nicholas Manousos

License

MIT License