1 files changed, 107 insertions, 0 deletions
diff --git a/src/couchdb/couch_httpd_external.erl b/src/couchdb/couch_httpd_external.erl
new file mode 100644
index 00000000..7ed3d51a
--- /dev/null
+++ b/src/couchdb/couch_httpd_external.erl
@@ -0,0 +1,107 @@
+% 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(couch_httpd_external).
+
+-export([handle_external_req/2]).
+
+-import(couch_httpd,[send_error/4]).
+
+-include("couch_db.hrl").
+
+-record(extern_resp_args, {
+    code = 200,
+    data = <<>>,
+    ctype = "application/json",
+    headers = []
+}).
+
+handle_external_req(#httpd{mochi_req=Req, 
+                        method=Verb,
+                        path_parts=[_DbName, _External, UrlName | Path]
+                    }=HttpReq, Db) ->
+    ReqBody = Req:recv_body(),
+    ParsedForm = case Req:get_primary_header_value("content-type") of
+        "application/x-www-form-urlencoded" ++ _ ->
+            mochiweb_util:parse_qs(ReqBody);
+        _ ->
+            []
+    end,
+    Response = couch_external_manager:execute(binary_to_list(UrlName), 
+        Db, Verb, Path, Req:parse_qs(), ReqBody, ParsedForm,
+        Req:parse_cookie()),
+        
+    case Response of
+    {unknown_external_server, Msg} ->
+        send_error(HttpReq, 404, <<"external_server_error">>, Msg);
+    _ ->
+        send_external_response(Req, Response)
+    end;
+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">>).
+
+send_external_response(Req, Response) ->
+    #extern_resp_args{
+        code = Code,
+        data = Data,
+        ctype = CType,
+        headers = Headers
+    } = parse_external_response(Response),
+    ?LOG_DEBUG("External Response ~p",[Response]),
+    Resp = Req:respond({Code, 
+        default_or_content_type(CType, Headers), chunked}),
+    Resp:write_chunk(Data),
+    Resp:write_chunk(""),
+    {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};
+            {<<"json">>, Value} ->
+                Args#extern_resp_args{
+                    data=?JSON_ENCODE(Value),
+                    ctype="application/json"};
+            {<<"body">>, Value} ->
+                Args#extern_resp_args{data=Value, ctype="text/html"};
+            {<<"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: ~s = ~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.