How to convert FetchAPI parsed Blob Results to Base64

Question

Have this module.exports file which fetches an image from an API endpoint. The API result is then parsed into a blob. After parsing the Blob object looks like this:

Blob {
  [Symbol(type)]: 'image/jpeg',
  [Symbol(buffer)]:
   <Buffer ff d8 ff db 00 43 00 08 06 06 07 06 05 08 07 07 07 09 09 08 0a 0c 14
0d 0c 0b 0b 0c 19 12 13 0f 14 1d 1a 1f 1e 1d 1a 1c 1c 20 24 2e 27 20 22 2c 23 1c
 ... > }

And here's the code:

// Pre Configuration
const fetch = require('node-fetch')

module.exports = async (req, res, photoKey) => {
    let photoUrl = null
    const apiURL = "https://media.heartenly.com/stg/CACHE/sc_thumb"
    const requestURL = `${apiURL}/${photoKey}`
    const response = await fetch(requestURL)
    const data = await response.blob()
    console.log(data)
}

Now what I want to do is to return base64 URL format of the returned blob, any ideas?

`data.toString('base64')`? or perhaps `data.buffer.toString('base64')` - I'm not familiar with blobs in nodejs — Jaromanda X, Sep 30 '18 at 10:24
here is a good answer: https://stackoverflow.com/questions/18650168/convert-blob-to-base64 — Nezir, Sep 30 '18 at 10:26
though, it's probably more like `const data = await response.buffer(); console.log(data.toString('base64'))` - because the Blob buffer seems to be hard to get at — Jaromanda X, Sep 30 '18 at 10:32

score 12 · Accepted Answer · answered Sep 30 '18 at 10:45

Looking at node-fetch, it looks impossible to get at the Blob buffer, so, the best bet is to do the following

use response.buffer instead of response.blob
use toString('base64') to get the data in base64

in other words:

const fetch = require('node-fetch');

module.exports = async (req, res, photoKey) => {
    let photoUrl = null;
    const apiURL = "https://media.heartenly.com/stg/CACHE/sc_thumb";
    const requestURL = `${apiURL}/${photoKey}`;
    const response = await fetch(requestURL);
    const data = await response.buffer()
    const b64 = data.toString('base64');
    console.log(b64);
};

How to convert FetchAPI parsed Blob Results to Base64

1 Answers1