Doc inconsistencies around responses and basic function template

[digerata]

Further:

How do you use JSON sent to a function?

Do you read it from the body?

let body = JSON.parse(req.body);

No, that kills the function. (Also, in my testing, it kills it so hard that 9 of 10 console.log statements are not shown in the cli logs. Which, again, is problematic if you are use logging to debug problems.)

So what is req.body? Can I just output the value?

console.log(req.body);

Yields exactly nothing. A blank. Even if the body did actually have content.

So from here one would search something like “netlify function request body is always blank” and you would get a list of forum posts here that talk about a bug in the CLI or improperly formatted JSON. A lot of posts that lead you to believe there is something wrong outside of your function code.

But that’s wrong. Buried in one of those posts is:

Function body is apparently readablestream?

I have a fetch request like this: fetch('/.netlify/functions/get-image', { method: 'POST', headers: { 'Content-Type': 'application/json', }, body: JSON.stringify({test: 'test'}) }) And a function called get-image.js like this: export default async (request, context) => { console.log(request.body); } The request.body is always a ReadableStream instead of JSON. This happens on dev and prod. I can get it working with await request.json(), but I’m unsure why this is …

And reading there, you finally find the answer:

req.json()

The answer refers to a Netlify blog post describing the change. Why isn’t this referring to the docs instead? Blog posts aren’t coming up in searches for dev issues.