Preserve Stack Traces In Node.js

I'm trying to preserve the call stack when handling errors that comes from e.g. net.js. The example below works but requires me to pre-allocate an error object for every call which

Solution 1:

You do have to acquire the stack trace up front, at the point of your new Error() call. You don't have to create an actual Error object; you can also use the V8 stack trace API to do it:

var stackHolder = {};
Error.captureStackTrace(stackHolder, nameOfCurrentFunction);

and now the stack is available as stackHolder.stack.

V8 lazy-formats the stack so this isn't as expensive as you might think; that stack property is actually a property getter which the first time it's run does the formatting work and then replaces itself with the output. (From the docs linked above: "For efficiency stack traces are not formatted when they are captured but on demand, the first time the stack property is accessed.")

Solution 2:

Just use one of existing long stack traces library, for example this one