Allows to limit the size of request and header lines, thus preventing
Cowboy from infinitely reading from the socket and never finding an
end of line.
Defaults to 4096 bytes.
Now init/3 can return one of the following values to enable loops:
- {loop, Req, State}
- {loop, Req, State, hibernate}
- {loop, Req, State, Timeout}
- {loop, Req, State, Timeout, hibernate}
Returning one of these tuples will activate looping in the HTTP handler.
When looping, handle/2 is never called. Instead, Cowboy will listen
for Erlang messages and forward them to the info/3 function of the
handler. If a timeout is defined, Cowboy will also close the connection
when no message has been received for Timeout milliseconds.
The info/3 function is defined as info(Msg, Req, State). It can return
either of the following tuples:
- {ok, Req, State}
- {loop, Req, State}
- {loop, Req, State, hibernate}
The first one ends the connection, calling terminate/2 before closing.
The others continue the loop.
Loops are useful when writing long-polling handlers that need to wait
and don't expect to receive anything. Therefore it is recommended to
set a timeout to close the connection if nothing arrives after a while
and to enable hibernate everywhere.
Normal HTTP handlers shouldn't need to use this and as such info/3
was made optional.
This change allows application developers to refuse websocket upgrades
by returning {shutdown, Req}. The application can also send a reply
with a custom error before returning from websocket_init/3, otherwise
an error 400 is sent.
Note that right now Cowboy closes the connection immediately. Also note
that neither terminate/3 nor websocket_terminate/3 will be called when
the connection is shutdown by websocket_init/3.
Now Cowboy checks headers sent to the client for the 'Connection'
header value, parses it, and checks whether it contains a 'close'
or 'keep-alive' value. It makes sure to close or keep the connection
alive depending on the value found there, if any.
Also change chunked replies to not close the connection by default
unless the application requests it.
If the websocket frame handling code in cowboy_http_websocket receives
only 1 byte at a time, it fails with a badmatch in
cowboy_http_websocket:websocket_data/4. This commit fixes the problem
and introduces a test of the correct behaviour.
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.
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.
Browsers get mad that the returned location address is not the same
as what they sent, since the :(80|443) is stripped.
Add a simple eunit test due to existing ct websockets tests not
covering this case.
The server now does a single recv (or more, but only if needed)
which is then sent to erlang:decode_packet/3 multiple times. Since
most requests are smaller than the default MTU on many platforms,
we benefit from this greatly.
In the case of requests with a body, the server usually read at
least part of the body on the first recv. This is bufferized
properly and used when later retrieving the body.
In the case of pipelined requests, we can end up reading many
requests in a single recv, which are then handled properly using
only the buffer containing the received data.
Now the server defines default headers that can be overwritten by the
handler simply by passing them to the reply/4 function. Default headers
include, for now, Connection and Content-Length headers. Note that it isn't
enough to change the Connection header to close a keep-alive connection
server-side.
