From the RFC:
The HEAD method is identical to GET except that the server MUST NOT
return a message-body in the response. The metainformation contained
in the HTTP headers in response to a HEAD request SHOULD be identical
to the information sent in response to a GET request.
Replaces the 'Connection' interpretation in cowboy_http_protocol
from raw value to the parsed value, looking for a single token
matching close/keep-alive instead of the whole raw value (which
could contain more than one token, for example with Firefox 6+
using websocket).
Introduce the functions cowboy_http_req:parse_header/2 and /3
to semantically parse the header values and return a proper
Erlang term.
The issue was that we were calling erlang:hibernate before a
receive .. after .. end call. Erlang hibernates the process before
reaching the receive instruction and we therefore couldn't enter
the after clause when hibernating.
This is now fixed by using erlang:send_after instead and receiving
that message instead of using an after clause.
To this end we are formatting the header names just like OTP does
except we do it for names of up to 32 characters, as there are
widely used header names of more than 20 characters, the limit that
OTP follows currently. An example of such header name would be
Sec-Websocket-Version.
The formatting itself is fairly simple: an uppercase character at
the start and after dashes, everything else lowercase.
Also sends a message 'shoot' that can be received by the protocol
to make sure Cowboy has had enough time to fully initialize the
socket. This message should be received before any socket-related
operations are performed.
WebSocket request connections are now moved from the pool 'default'
to the pool 'websocket', meaning we can have a lot of running
WebSockets despite having a low 'max_connections' setting.
Improves the readability of websocket handler code by having
two functions: websocket_handle/3 handles the packets received
from the socket, removing the tuple construct that was otherwise
needed, so only websocket_handle(Data, Req, State) is needed now;
websocket_info/3 handles the messages that the websocket handler
process received, as websocket_info(Info, Req, State).
Both functions return values are handled identically by Cowboy
so nothing changes on that end.
This ensures that an error thrown in handler_terminate/4 will be
shown after the error from handler_call/6, in the expected order.
As we already call WebSocketHandler:terminate/3, this should
fix issue #23.
