Javascript - How to convert buffer to a string?

Question

This is example of converting String to a Buffer and back to String:

let bufferOne = Buffer.from('This is a buffer example.');
console.log(bufferOne);

// Output: <Buffer 54 68 69 73 20 69 73 20 61 20 62 75 66 66 65 72 20 65 78 61 6d 70 6c 65 2e>

let json = JSON.stringify(bufferOne);
let bufferOriginal = Buffer.from(JSON.parse(json).data);
console.log(bufferOriginal.toString('utf8'));
// Output: This is a buffer example.

Now imagine someone just give you only this string as a starting point:
<Buffer 54 68 69 73 20 69 73 20 61 20 62 75 66 66 65 72 20 65 78 61 6d 70 6c 65 2e>
- how would you convert it to regular value of this 'buffer' string?

I tried with:

   let buffer = '<Buffer 54 68 69 73 20 69 73 20 61 20 62 75 66 66 65 72 20 65 78 61 6d 70 6c 65 2e>'
    json = JSON.stringify(buffer);
    console.log(json);

Gives output:

"<Buffer 54 68 69 73 20 69 73 20 61 20 62 75 66 66 65 72 20 65 78 61 6d 70 6c 65 2e>"

Solution 1

No native way for that, but I wrote a sample method for you:

function bufferFromBufferString(bufferStr) {
    return Buffer.from(
        bufferStr
            .replace(/[<>]/g, '') // remove < > symbols from str
            .split(' ') // create an array splitting it by space
            .slice(1) // remove Buffer word from an array
            .reduce((acc, val) => 
                acc.concat(parseInt(val, 16)), [])  // convert all strings of numbers to hex numbers
     )
}

result:

const newBuffer = bufferFromBufferString('<Buffer 54 68 69 73 20 69 73 20 61 20 62 75 66 66 65 72 20 65 78 61 6d 70 6c 65 2e>')
> newBuffer
<Buffer 54 68 69 73 20 69 73 20 61 20 62 75 66 66 65 72 20 65 78 61 6d 70 6c 65 2e>
> newBuffer.toString()
'This is a buffer example.'

Solution 2

Automatically converted when concatenated with an empty string:

console.log('' + bufferOne)

Comments

[Krishna Prashatt]

Your buffer variable is already a string!

[Alexander Santos]

This doesn't really replies the question. I know it's already string, but he needs to do as the best answer states (Convert from the Buffer-string-like representation to string).

[A1rPun]

Better use toString