Ask HN | http compliance if post with content-length:0

3 pointswaxzce3 comments

Hi

I have a corner case :-)

A library client do a POST request on my server, with 2 headers : > Content-type: application/json > Content-length: 0

So ATM the server response is 400 (bad request) because json is invalid

So the question is : When the content-length of a request is 0, should we parse the body or not ?

To my mind, as long as the Content-type header is set, the server should try to parse the body accordingly.

In the case of JSON, an empty body cannot be a JSON representation, but for other formats an empty body can have a meaning.

For instance for a plain text content-type, no string != empty string

What does it matter?

What you should do is have the error messages be the same for detecting a length 0 submission and of attempting to parse the empty string as JSON.

You can think of the check for length==0 and length==1 as a sort of optimization (no JSON document can be 1 byte long), rather than a corner case.