diff options
Diffstat (limited to 'src/chttpd_external.erl')
| -rw-r--r-- | src/chttpd_external.erl | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/src/chttpd_external.erl b/src/chttpd_external.erl new file mode 100644 index 00000000..d096bff9 --- /dev/null +++ b/src/chttpd_external.erl @@ -0,0 +1,166 @@ +% Licensed under the Apache License, Version 2.0 (the "License"); you may not +% use this file except in compliance with the License. You may obtain a copy of +% the License at +% +% http://www.apache.org/licenses/LICENSE-2.0 +% +% Unless required by applicable law or agreed to in writing, software +% distributed under the License is distributed on an "AS IS" BASIS, WITHOUT +% WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the +% License for the specific language governing permissions and limitations under +% the License. + +-module(chttpd_external). + +-export([handle_external_req/2, handle_external_req/3]). +-export([send_external_response/2, json_req_obj/2]). +-export([default_or_content_type/2, parse_external_response/1]). + +-import(chttpd,[send_error/4]). + +-include("chttpd.hrl"). + +% handle_external_req/2 +% for the old type of config usage: +% _external = {chttpd_external, handle_external_req} +% with urls like +% /db/_external/action/design/name +handle_external_req(#httpd{ + path_parts=[_DbName, _External, UrlName | _Path] + }=HttpReq, Db) -> + process_external_req(HttpReq, Db, UrlName); +handle_external_req(#httpd{path_parts=[_, _]}=Req, _Db) -> + send_error(Req, 404, <<"external_server_error">>, <<"No server name specified.">>); +handle_external_req(Req, _) -> + send_error(Req, 404, <<"external_server_error">>, <<"Broken assumption">>). + +% handle_external_req/3 +% for this type of config usage: +% _action = {chttpd_external, handle_external_req, <<"action">>} +% with urls like +% /db/_action/design/name +handle_external_req(HttpReq, Db, Name) -> + process_external_req(HttpReq, Db, Name). + +process_external_req(HttpReq, Db, Name) -> + + Response = couch_external_manager:execute(binary_to_list(Name), + json_req_obj(HttpReq, Db)), + + case Response of + {unknown_external_server, Msg} -> + send_error(HttpReq, 404, <<"external_server_error">>, Msg); + _ -> + send_external_response(HttpReq, Response) + end. + +json_req_obj(#httpd{mochi_req=Req, + method=Verb, + path_parts=Path, + req_body=ReqBody + }, Db) -> + Body = case ReqBody of + undefined -> Req:recv_body(); + Else -> Else + end, + ParsedForm = case Req:get_primary_header_value("content-type") of + "application/x-www-form-urlencoded" ++ _ -> + mochiweb_util:parse_qs(Body); + _ -> + [] + end, + Headers = Req:get(headers), + Hlist = mochiweb_headers:to_list(Headers), + Customer = cloudant_util:customer_name( + Req:get_header_value("X-Cloudant-User"), Req:get_header_value("Host")), + {ok, Info} = ?COUCH:get_db_info(Db, Customer), + + % send correct path to customer - BugzID 6849 + CustomerBin = list_to_binary(Customer), + Len = byte_size(CustomerBin), + FixedPath = case Path of + [<<CustomerBin:Len/binary, "/", DbName/binary>> | Rest] -> + [DbName | Rest]; + NoCustomer -> + NoCustomer + end, + + % add headers... + {[{<<"info">>, {Info}}, + {<<"verb">>, Verb}, + {<<"path">>, FixedPath}, + {<<"query">>, to_json_terms(Req:parse_qs())}, + {<<"headers">>, to_json_terms(Hlist)}, + {<<"body">>, Body}, + {<<"form">>, to_json_terms(ParsedForm)}, + {<<"cookie">>, to_json_terms(Req:parse_cookie())}, + {<<"userCtx">>, couch_util:json_user_ctx(Db)}]}. + +to_json_terms(Data) -> + to_json_terms(Data, []). +to_json_terms([], Acc) -> + {lists:reverse(Acc)}; +to_json_terms([{Key, Value} | Rest], Acc) when is_atom(Key) -> + to_json_terms(Rest, [{list_to_binary(atom_to_list(Key)), list_to_binary(Value)} | Acc]); +to_json_terms([{Key, Value} | Rest], Acc) -> + to_json_terms(Rest, [{list_to_binary(Key), list_to_binary(Value)} | Acc]). + + +send_external_response(#httpd{mochi_req=MochiReq}, Response) -> + #extern_resp_args{ + code = Code, + data = Data, + ctype = CType, + headers = Headers + } = parse_external_response(Response), + Resp = MochiReq:respond({Code, + default_or_content_type(CType, Headers ++ chttpd:server_header()), Data}), + {ok, Resp}. + +parse_external_response({Response}) -> + lists:foldl(fun({Key,Value}, Args) -> + case {Key, Value} of + {"", _} -> + Args; + {<<"code">>, Value} -> + Args#extern_resp_args{code=Value}; + {<<"stop">>, true} -> + Args#extern_resp_args{stop=true}; + {<<"json">>, Value} -> + Args#extern_resp_args{ + data=?JSON_ENCODE(Value), + ctype="application/json"}; + {<<"body">>, Value} -> + Args#extern_resp_args{data=Value, ctype="text/html; charset=utf-8"}; + {<<"base64">>, Value} -> + Args#extern_resp_args{ + data=couch_util:decodeBase64(Value), + ctype="application/binary" + }; + {<<"headers">>, {Headers}} -> + NewHeaders = lists:map(fun({Header, HVal}) -> + {binary_to_list(Header), binary_to_list(HVal)} + end, Headers), + Args#extern_resp_args{headers=NewHeaders}; + _ -> % unknown key + Msg = lists:flatten(io_lib:format("Invalid data from external server: ~p", [{Key, Value}])), + throw({external_response_error, Msg}) + end + end, #extern_resp_args{}, Response). + +default_or_content_type(DefaultContentType, Headers) -> + {ContentType, OtherHeaders} = lists:partition( + fun({HeaderName, _}) -> + HeaderName == "Content-Type" + end, Headers), + + % XXX: What happens if we were passed multiple content types? We add another? + case ContentType of + [{"Content-Type", SetContentType}] -> + TrueContentType = SetContentType; + _Else -> + TrueContentType = DefaultContentType + end, + + HeadersWithContentType = lists:append(OtherHeaders, [{"Content-Type", TrueContentType}]), + HeadersWithContentType. |