How to insert a new contact using Google CardDAV API?

Google CardDAV API Developer's Guide is very brief when it comes to contact manipulation. The only hint about how to insert a new contact is this:

Client applications issue a POST request with the new contact in VCard 3.0 format. The response will contain the ID of the new contact.

This is the request I issue, but the response I get is 400 Bad Request:

POST https://www.googleapis.com/carddav/v1/principals/[email protected]/lists/default/ HTTP/1.1
Authorization: Bearer ya29.foobar
Content-Type: text/vcard; charset="UTF-8"
Host: www.googleapis.com
Content-Length: 77
Expect: 100-continue
Connection: Keep-Alive

BEGIN:VCARD
VERSION:3.0
FN:Foo Bar
UID:abc-def-fez-1234546578
END:VCARD

Anybody has a clue what am I missing here?

Solution

Do a PUT, not a POST. Like this:

PUT /carddav/v1/principals/[email protected]/lists/default/DEADBEEF.vcf
If-None-Match: *
Authorization: ...
Host: www.googleapis.com
Content-Type: text/vcard; charset="UTF-8"
Expect: 100-continue

BEGIN:VCARD
VERSION:3.0
PRODID:-//YouYou//Windows//EN
FN:Foo Bar
N:Bar;Foo;;;
UID:DEADBEEF
END:VCARD