diff options
Diffstat (limited to 'src/cowboy_http_rest.erl')
| -rw-r--r-- | src/cowboy_http_rest.erl | 31 |
1 files changed, 20 insertions, 11 deletions
diff --git a/src/cowboy_http_rest.erl b/src/cowboy_http_rest.erl index ee67b36..8bce1d4 100644 --- a/src/cowboy_http_rest.erl +++ b/src/cowboy_http_rest.erl @@ -41,7 +41,7 @@ charset_a :: undefined | binary(), %% Cached resource calls. - etag :: undefined | no_call | binary(), + etag :: undefined | no_call | {strong | weak, binary()}, last_modified :: undefined | no_call | calendar:datetime(), expires :: undefined | no_call | calendar:datetime() }). @@ -487,14 +487,10 @@ if_match_exists(Req, State) -> if_match(Req, State, EtagsList) -> {Etag, Req2, State2} = generate_etag(Req, State), - case Etag of - no_call -> - precondition_failed(Req2, State2); - Etag -> - case lists:member(Etag, EtagsList) of - true -> if_unmodified_since_exists(Req2, State2); - false -> precondition_failed(Req2, State2) - end + case lists:member(Etag, EtagsList) of + true -> if_unmodified_since_exists(Req2, State2); + %% Etag may be `undefined' which cannot be a member. + false -> precondition_failed(Req2, State2) end. if_match_musnt_exist(Req, State) -> @@ -534,7 +530,7 @@ if_none_match_exists(Req, State) -> if_none_match(Req, State, EtagsList) -> {Etag, Req2, State2} = generate_etag(Req, State), case Etag of - no_call -> + undefined -> precondition_failed(Req2, State2); Etag -> case lists:member(Etag, EtagsList) of @@ -810,10 +806,14 @@ set_resp_etag(Req, State) -> {Req2, State2}; Etag -> {ok, Req3} = cowboy_http_req:set_resp_header( - <<"Etag">>, Etag, Req2), + <<"ETag">>, encode_etag(Etag), Req2), {Req3, State2} end. +-spec encode_etag({strong | weak, binary()}) -> iolist(). +encode_etag({strong, Etag}) -> [$",Etag,$"]; +encode_etag({weak, Etag}) -> ["W/\"",Etag,$"]. + set_resp_expires(Req, State) -> {Expires, Req2, State2} = expires(Req, State), case Expires of @@ -834,6 +834,15 @@ generate_etag(Req, State=#state{etag=undefined}) -> case call(Req, State, generate_etag) of no_call -> {undefined, Req, State#state{etag=no_call}}; + %% Previously the return value from the generate_etag/2 callback was set + %% as the value of the ETag header in the response. Therefore the only + %% valid return type was `binary()'. If a handler returns a `binary()' + %% it must be mapped to the expected type or it'll always fail to + %% compare equal to any entity tags present in the request headers. + %% @todo Remove support for binary return values after 0.6. + {Etag, Req2, HandlerState} when is_binary(Etag) -> + [Etag2] = cowboy_http:entity_tag_match(Etag), + {Etag2, Req2, State#state{handler_state=HandlerState, etag=Etag2}}; {Etag, Req2, HandlerState} -> {Etag, Req2, State#state{handler_state=HandlerState, etag=Etag}} end; |