diff options
author | Loïc Hoguin <[email protected]> | 2017-04-27 15:23:57 +0200 |
---|---|---|
committer | Loïc Hoguin <[email protected]> | 2017-04-27 15:23:57 +0200 |
commit | 32db544782f2528ed0916eecb200f75924dcc407 (patch) | |
tree | ef8746ab021a8172ac84e9f72062922ec4263619 /src/gun_sse.erl | |
parent | e8c08c95b896bf9d2dd299e5fdbff50f714e8749 (diff) | |
download | gun-32db544782f2528ed0916eecb200f75924dcc407.tar.gz gun-32db544782f2528ed0916eecb200f75924dcc407.tar.bz2 gun-32db544782f2528ed0916eecb200f75924dcc407.zip |
Add content handlers and built-in SSE support
Content handlers are a chain of modules implementing callbacks
that receive the body of responses and may modify it (for example
for decompressing the content) or act upon it (like sending a
message to the owner process.
The gun_sse content handler module can be used to translate
text/event-stream events on the fly and deliver them to the
owner process as a {gun_sse...} message.
This feature is currently not documented and is only tested
against a public server. It requires an up to date Cowlib.
Diffstat (limited to 'src/gun_sse.erl')
-rw-r--r-- | src/gun_sse.erl | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/src/gun_sse.erl b/src/gun_sse.erl new file mode 100644 index 0000000..4fe7419 --- /dev/null +++ b/src/gun_sse.erl @@ -0,0 +1,49 @@ +%% Copyright (c) 2017, Loïc Hoguin <[email protected]> +%% +%% Permission to use, copy, modify, and/or distribute this software for any +%% purpose with or without fee is hereby granted, provided that the above +%% copyright notice and this permission notice appear in all copies. +%% +%% THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES +%% WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF +%% MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR +%% ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES +%% WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN +%% ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF +%% OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + +-module(gun_sse). +-behavior(gun_content_handler). + +-export([init/5]). +-export([handle/3]). + +-record(state, { + reply_to :: pid(), + stream_ref :: reference(), + sse_state :: cow_sse:state() +}). + +%% @todo In the future we want to allow different media types. +%% @todo For text/event-stream specifically, the parameters must be ignored. + +-spec init(pid(), reference(), _, cow_http:headers(), _) + -> {ok, #state{}} | disable. +init(ReplyTo, StreamRef, _, Headers, _) -> + case lists:keyfind(<<"content-type">>, 1, Headers) of + {_, <<"text/event-stream">>} -> + {ok, #state{reply_to=ReplyTo, stream_ref=StreamRef, + sse_state=cow_sse:init()}}; + _ -> + disable + end. + +-spec handle(_, binary(), State) -> {done, State} when State::#state{}. +handle(IsFin, Data, State=#state{reply_to=ReplyTo, stream_ref=StreamRef, sse_state=SSE0}) -> + case cow_sse:parse(Data, SSE0) of + {event, Event, SSE} -> + ReplyTo ! {gun_sse, self(), StreamRef, Event}, + handle(IsFin, <<>>, State#state{sse_state=SSE}); + {more, SSE} -> + {done, State#state{sse_state=SSE}} + end. |