stackback

What is stackback?

The stackback npm package is designed to provide an easy way to extract a stack trace from a given Error object. It parses the stack property of Error objects to return an array of call site objects, which can be used for debugging or logging purposes. This can be particularly useful in environments where understanding the sequence of function calls leading to an error is crucial for diagnosing issues.

What are stackback's main functionalities?

Extracting stack traces from Error objects

This feature allows developers to pass an Error object to the stackback function, which returns an array of call site objects representing the stack trace. Each call site object provides detailed information about each stack frame, such as the file name, line number, and column number where the error occurred. This can be invaluable for debugging by providing a clear path of execution up to the point where the error was thrown.

const stackback = require('stackback');
const error = new Error('Test Error');
const stack = stackback(error);
console.log(stack);

Other packages similar to stackback

error-stack-parser

Similar to stackback, error-stack-parser is a package that extracts stack traces from Error objects. It provides a slightly different API and may offer more detailed parsing in some cases. The choice between stackback and error-stack-parser might come down to personal preference or specific requirements regarding the format and details of the parsed stack trace.

stack-trace

The stack-trace package offers functionality to capture and analyze stack traces in Node.js applications. While it shares the core feature of extracting stack traces with stackback, stack-trace provides additional utilities for working with and manipulating stack traces, such as filtering or mapping over stack frames. This makes it a more feature-rich option, albeit potentially more complex to use for simple stack trace extraction tasks.

README

stackback

Returns an array of CallSite objects for a captured stacktrace. Useful if you want to access the frame for an error object.

use

var stackback = require('stackback');

// error generated from somewhere
var err = new Error('some sample error');

// stack is an array of CallSite objects
var stack = stackback(err);

CallSite object

From the V8 StackTrace API

The structured stack trace is an Array of CallSite objects, each of which represents a stack frame. A CallSite object defines the following methods

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?

install

npm install stackback