url
  http://example.com/index.html
method
  POST
expected
  abcdefghijklmnopqrstuvwxyz1234567890abcdef
expected_url
  http://example.com/index2.html
----------
POST /index.html HTTP/1.1
Host: example.com
Connection: close
Content-Length: 0
User-Agent: HTTP-Tiny/VERSION

----------
HTTP/1.1 303 See Other
Date: Thu, 03 Feb 1994 00:00:00 GMT
Content-Type: text/html
Content-Length: 53
Location: http://example.com/index2.html

<a href="http://example.com/index2.html">redirect</a>

----------
GET /index2.html HTTP/1.1
Host: example.com
Connection: close
User-Agent: HTTP-Tiny/VERSION

----------
HTTP/1.1 200 OK
Date: Thu, 03 Feb 1994 00:00:00 GMT
Content-Type: text/plain
Content-Length: 42

abcdefghijklmnopqrstuvwxyz1234567890abcdef

