JavaScript improved error handling

javascript-improved-error-handling.js

const os = require('os');

class ServerError extends Error {
  constructor(message, innerError) {
    super();
    this.name = this.constructor.name;
    this.innerError = innerError;

    // Borrowed from: https://stackoverflow.com/questions/35392675/how-to-override-error-stack-getter
    Object.defineProperty(this, 'message', {
      get: () => {
        if (this.innerError) {
          return `${this._message}: ${this.innerError.name} - ${this.innerError.message}`;
        }
        return this._message;
      },
      set: value => this._message = value
    });
    this.message = message;

    Object.defineProperty(this, 'stack', {
      get: () => {
        const lines = (this.innerError ? this.innerError.stack : this._stack).split(os.EOL);
        while (lines[0].startsWith('Error') || lines[0].startsWith('    at new ')) {
          lines.splice(0, 1);
        }
        return lines.join(os.EOL);
      },
      set: value => this._stack = value
    });
    this.stack = new Error().stack;
  }
}

class DatabaseError extends ServerError {
}

function dbFunction() {
  try {
    throw new Error('Mongo was throwing an error');
  } catch (err) {
    throw new DatabaseError('Unexpected error while doing something with the database.', err);
  }
}

function callDbFunction() {
  try {
    dbFunction();
  } catch (err) {
    throw new ServerError('Something went wrong in the server', err);
  }
}

function letsThrowNormalError() {
  throw new Error('This is a simple error');
}

function handleAnyError() {
  try {
    letsThrowNormalError();
  } catch (err) {
    throw new ServerError('A normal error occurred', err);
  }
}

function serverFunction() {
  throw new ServerError('Our server won\'t work anymore.');
}

try {
  callDbFunction();
  // handleAnyError();
  // serverFunction();
} catch (err) {
  console.error(err.name, err.message, os.EOL, err.stack);
  // console.log(err);
}