Cbor address to bech32 type address in JS or python

Question

I have managed to retrive a user address from a dapp connector wallet using JS:

api_promise = window.cardano.{wallet}.enable();
api_promise.then(function(api) {
  addr_promise = api.getUsedAddresses();
  addr_promise.then(
    function(addr) {
      value[0];  // this is a CBOR address !
...

I get this type of (presumably CBOR) address: 012f4d0b584ecb52e4e4b8e78e4ce77a6f822e59ede3277305fd526b71824b2d2740284cf6a28e2a512cc4a00f41004c18ed728a0f7a04eb29 Apparently with some skill it could be read using this -> https://cbor.me.

# Is there any method to extract a shelley addr_34.... using JS or python?

Working implementations are available in node.js, but I'm using flask (python + JS). And I'm struggling to make it work wit packages cbor2 and bech32. For example I tried cbor2.loads(bytes(addr_str, 'utf-8')) without success.

My further goal is to query blockfrost.

Answer 1

You can also use typhonjs used by typhonwallet. It's a Pure JS library not dependent on WASM.

Install

npm i @stricahq/typhonjs

Usage

const typhonjs =  require("@stricahq/typhonjs");

const bech32Address = typhonjs.utils
  .getAddressFromHex("012f4d0b584ecb52e4e4b8e78e4ce77a6f822e59ede3277305fd526b71824b2d2740284cf6a28e2a512cc4a00f41004c18ed728a0f7a04eb29")
  .getBech32();

Answer 2

First install the npm module:

npm i @emurgo/cardano-serialization-lib-browser

Then you need a wasm loader module

class wasm {
  async load() {
    if (this._wasm) return;
    /**
     * @private
     */
    this._wasm = await import(
      "@emurgo/cardano-serialization-lib-browser/cardano_serialization_lib"
    );
  }

  get Cardano() {
    return this._wasm;
  }
}

export default new wasm();

Then import into your module/component using:

import WASMLoader from "../../utils/Loader";

Now you should be able to use wasm module to convert the CBOR address into bech32 (addr1.., stake1.. etc)

const getAddressToBech32 = async () => {
    await WASMLoader.load();
    const address = (await api.getUsedAddresses())[0];
    return WASMLoader.Cardano.Address.from_bytes(Buffer.from(address,"hex")).to_bech32();
};

Now that you have a bech32 address you should be able to use with for blockfrost API queries