413 - Request Entity Too Large

Question

I can upload small drafts OK using the metadata endpoint (https://www.googleapis.com/gmail/v1/users/me/drafts), e.g.:

{\"message\":{\"raw\":\"TUlNRS1WZXJzaW9         


        

Answer 1

You need to use the /upload "media upload" path to upload anything over a few MB. The URL and POST format are slightly different:

You'd do:

1. POST https://www.googleapis.com/upload/gmail/v1/users/userId/drafts
2. add a HTTP header like "Content-type: multipart/related; boundary=\"part_boundary\""
3. POST body looks more like:

--part_boundary
Content-Type: application/json; charset=UTF-8

{
}

--part_boundary
Content-Type: message/rfc822

From: script@example.org
To: user@example.com
Subject: test

body here

--part_boundary--

See this for more info (which then links to this).