GET request with curl. No errors, but Content-Length equals 0

Question

Simple GET request with curl returns empty body (Content-Length: 0):

curl -v https://www.flyorientthai.com/booking/en/index.php

On the other hand wget can handle that url just fine:

wget https://www.flyorientthai.com/booking/en/index.php

What's wrong with curl?

Donnetta

Maybe server requires certain HTTP headers that curl doesn't normally send but wget does – Perreault

@MJafarMash you're absolutely right :) 'Connection: Keep-Alive' header was missing with curl request and turned out it was critical. – Donnetta

What kind of broken server is this. Keep-Alive is implicit with HTTP/1.1, so this header would be redundant. But yes, using curl -v -H "Connection: keep-alive" gives the expected response while without the header not. – Turanian

Answer 1

Turned out 'Connection: Keep-Alive' header is required. It's added by default to request with wget but not with curl.

Donnetta

Answer 2

For anyone using "Copy as cURL" in the Chrome developer tools network tab to generate a curl command — one of the lines in the generated curl command is a header that looks something like...

-H 'If-None-Match: W/"18f6a6-6p8AL7X/p71IhN/WztZm60Aue4k"'

That causes the server to return an empty 304 response if nothing's changed. Just whip it out.

Statecraft

Answer 3

Let's try "Content-Type: application/x-www-form-urlencodeds"

Argillite