JSON.parse() not failing when it should fail

Question

I have the following NodeJS code:

const msg = Buffer.from([ 34, 115, 106, 100, 104, 34 ]);
const a = JSON.parse(msg.toString('utf-8'))
console.log(a);

The msg buffer is basically the string "sjdh" when using .toString('utf-8') on it.
How come when I run this, JSON.parse is able to parse what is essentially the string "sjdh" and returns it as a result to a?

Does this answer your question? [Can JSON start with "\["?](https://stackoverflow.com/questions/5034444/can-json-start-with) — Tim Biegeleisen, Feb 23 '23 at 15:30
An array is valid JSON, according to the docs and duplicate above. — Tim Biegeleisen, Feb 23 '23 at 15:30
Why is it an array though? Isn't the buffer being converted to a plain string "sdjh" when using .toString('utf-8')? — HarelDanieli, Feb 23 '23 at 15:30

Konrad · Accepted Answer · 2023-02-23T15:35:29.740

1

Some types are allowed to not be wrapped in an object or array by JSON.parse

Read more here What is the minimum valid JSON?

console.log(JSON.parse('"asdad"'))
console.log(JSON.parse('null'))

edited Feb 23 '23 at 15:35

answered Feb 23 '23 at 15:32

Konrad

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I see! Interesting, so it treats it as a single JSON string which is why it's valid. Well then how should I avoid this? Remove the " characters after using .toString()? – HarelDanieli Feb 23 '23 at 15:33
1

https://stackoverflow.com/a/3710506 you can also just check after parsing if it's an array or object – Konrad Feb 23 '23 at 15:38

JSON.parse() not failing when it should fail

1 Answers1