如何正确地将节点js中的Error对象转换为字符串？

Question

This error throws up whenever I enter a duplicate entry in mysql.

{ [Error: ER_DUP_ENTRY: Duplicate entry 'sample@gmail.com' for key 'email '] code: 'ER_DUP_ENTRY', errno: 1062, sqlState: '23000', index: 0 }

What I want to do is turn this Error object into a string. I tried using JSON.stringify() and when I printed it on the console, only the last part got converted into a string :

{"code":"ER_DUP_ENTRY","errno":1062,"sqlState":"23000","index":0}

I need to convert the first part as well of the error, the one inside the [ ] so that I am able to diagnose duplicates properly. How do I retrieve that part whenever I convert an Error object into a string?

Answer 1

I thought I had to use JSON for this problem because of the way the Error object was formatted. How I solved this one was just to use

err.toString()

Answer 2

For future reference, just in case you wish to extract the Error messsage. Use error.message to extract the message. Here is a reference: https://nodejs.org/api/errors.html#errors_error_message

Answer 3

To get the full stack use stack property of the Error object:

console.log(error.stack)

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error/stack