What is it?

exception-formatter is an NPM package that takes exceptions or stack traces that would normally look like this:

and makes them look like this:

or, in HTML, like this:

Features

• Automatically highlights your code (as opposed to included modules or node.js system libraries) since your code is likely where the problem is.
• Strips leading project paths to make exceptions more readable.
• Can read longjohn and streamline async stacks.

Installation

npm install --save exception-formatter

Usage

exceptionFormatter = require('exception-formatter');
console.log( exceptionFormatter(err, options) );

Where err is either an Error, a {stack} object, or a string containing a stack trace. options is an optional parameter containing the following:

• options.format - one of 'ascii', 'ansi', 'html'. 'ascii' and 'ansi' are identical, except that 'ansi' will use ANSI color codes to highlight lines.
• options.maxLines - The maximum number of lines to print from the exception. 0 or null for unlimited (the default.) "auto" to truncate after the last line in your source code.
• options.basepath - this is your project's root folder. If you're writing code in src/myFile.js, then this should be path.resolve(__dirname, '..'). This path will be stripped from the start of every filename in the exception, and is also used to help decide which code is "your code" and which is not. If this is not provided, then process.cwd() is used by default.
• options.basepathReplacement - String used to replace the basepath. Defaults to "./".
• options.colors - (Only for format = 'ansi') If true (the default) then lines which are "your code" will be bolded and colorized. If false, then lines will only be bolded.
• options.inlineStyle - (Only for format = 'html') If this option is true, then each line will be styled with inline style attributes. If false, each line will be given a class instead and you can do your own styling. Note that inline styline is usually required if you want to email an exception, since email clients will generally ignore style sheets.

"Your Code"

exception-formatter will mark code as "your code" if it is in options.basepath, and if it does not contain node_modules anywhere in it's path.