eccrypto | JavaScript Elliptic curve cryptography library | Cryptography library

I want to encrypt and decrypt the message based on ECIES using this library JavaScript Elliptic curve cryptography library. I want to import my private key and get the public key from it because I do not have a new private key generated each time I run the code.

The code:

There is a lot of code involved in this process, so I will explain the best way possible to narrow down the problem. First, the user signs up and sends an object with other nested objects and arrays to the middleware. The middleware...

Intro:

Hello Community. I have been trying to encrypt a message with the https://www.npmjs.com/package/eccrypto ~ eccrypto.encrypt() function then .toString('hex') the value after encrypting but when I return the hexed value, it gives me [object object]. Why does this happen? I am new to javascript and eccrypto and any insight will be appreciated.

Relevant Code:

Intro:

So I am new to JavaScript and I would like to know how I can use the return from an async function without using .then or anything of that sort (if not, then is it possible to use this in a way that I can access the return in scope of the signupData() function). So I am encrypting things with ECIES scheme using Secp256k1 keys to be sent to the API for later usage, however, I think the .encrypt under the encryptMes section in the post invokes a promise. Below is relevant code:

signup.html

I am using react in javascript and I try to encrypt array elements using a loop, then I want to push each result in an element of the new array, I use this code:

I've been having a really hard time figuring out how to store a Secp256k1 privateKey from multiple libraries (currently on this one for ECIES encryption: https://npm.io/package/@toruslabs/eccrypto).

I have tried encoding and decoding with base64, many implementations of functions that copy array buffer for input encoded string to localStoarge and corresponding output Uint8Array from localStorage, I tried it with IndexedDB, JSON.stringify and parse do not work with binary data, and so many more variations.

When I go through the array buffer elements individually to copy it into a new Uint8Array, I get a similar private key, but with two missing key/field's (parent and offset) which I believe is why every library I have tried so far returns something a long the lines of "bad private key" when I try generating the public key from them.

I am exhausted and I would like some professional insight for my lack of skill in this particular subject. So how can I store (in any way as long as it's client/local) a Secp256k1 private key in a way that if I call it from that persistent client sided data base, they can be used to generate the public keys?

It's been a few hours since I began reading about IndexedDB and I am having some issues. This is code I followed from https://medium.com/@AndyHaskell2013/build-a-basic-web-app-with-indexeddb-8ab4f83f8bda and https://gist.github.com/JamesMessinger/a0d6389a5d0e3a24814b and it's just put together poorly for comprehension's sake. So what I am trying to do is store a secret key into IndexedDB so that I can use it to encrypt things with the ECIES scheme.

Relevant code (sequential order):

My skills in javascript are minimal and I am unsure of how to get the original Uint8Array(32) after it's been sent to localStorage, decoded and converted back to Uint8Array(32). Below you will see that I tried stringifying a private key then base64 encoding it so that it gets sent to localStorage for later usage:

I am using eccrypto library in javascript for encryption using the ECIES algorithm (curve- secp256k1). The cipher generated by encryption in JS code could not be decrypted in Kotlin.

Here is the Javascript code.