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Diffstat (limited to 'apps/chttpd/src/chttpd_show.erl')
| -rw-r--r-- | apps/chttpd/src/chttpd_show.erl | 311 |
1 files changed, 311 insertions, 0 deletions
diff --git a/apps/chttpd/src/chttpd_show.erl b/apps/chttpd/src/chttpd_show.erl new file mode 100644 index 00000000..fba7f040 --- /dev/null +++ b/apps/chttpd/src/chttpd_show.erl @@ -0,0 +1,311 @@ +% 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_show). + +-export([handle_doc_show_req/3, handle_doc_update_req/3, handle_view_list_req/3]). + +-include_lib("couch/include/couch_db.hrl"). + +-import(chttpd, + [send_json/2,send_json/3,send_json/4,send_method_not_allowed/2, + start_json_response/2,send_chunk/2,last_chunk/1,send_chunked_error/2, + start_chunked_response/3, send_error/4]). + +-record(lacc, { + req, + resp = nil, + qserver, + lname, + db, + etag +}). + +% /db/_design/foo/_show/bar/docid +% show converts a json doc to a response of any content-type. +% it looks up the doc an then passes it to the query server. +% then it sends the response from the query server to the http client. + +maybe_open_doc(Db, DocId) -> + case fabric:open_doc(Db, DocId, [conflicts]) of + {ok, Doc} -> + Doc; + {not_found, _} -> + nil + end. + +handle_doc_show_req(#httpd{ + path_parts=[_, _, _, _, ShowName, DocId] + }=Req, Db, DDoc) -> + + % open the doc + Doc = maybe_open_doc(Db, DocId), + + % we don't handle revs here b/c they are an internal api + % returns 404 if there is no doc with DocId + handle_doc_show(Req, Db, DDoc, ShowName, Doc, DocId); + +handle_doc_show_req(#httpd{ + path_parts=[_, _, _, _, ShowName, DocId|Rest] + }=Req, Db, DDoc) -> + + DocParts = [DocId|Rest], + DocId1 = ?l2b(string:join([?b2l(P)|| P <- DocParts], "/")), + + % open the doc + Doc = maybe_open_doc(Db, DocId1), + + % we don't handle revs here b/c they are an internal api + % pass 404 docs to the show function + handle_doc_show(Req, Db, DDoc, ShowName, Doc, DocId1); + +handle_doc_show_req(#httpd{ + path_parts=[_, _, _, _, ShowName] + }=Req, Db, DDoc) -> + % with no docid the doc is nil + handle_doc_show(Req, Db, DDoc, ShowName, nil); + +handle_doc_show_req(Req, _Db, _DDoc) -> + send_error(Req, 404, <<"show_error">>, <<"Invalid path.">>). + +handle_doc_show(Req, Db, DDoc, ShowName, Doc) -> + handle_doc_show(Req, Db, DDoc, ShowName, Doc, null). + +handle_doc_show(Req, Db, DDoc, ShowName, Doc, DocId) -> + % get responder for ddoc/showname + CurrentEtag = show_etag(Req, Doc, DDoc, []), + chttpd:etag_respond(Req, CurrentEtag, fun() -> + JsonReq = chttpd_external:json_req_obj(Req, Db, DocId), + JsonDoc = couch_query_servers:json_doc(Doc), + [<<"resp">>, ExternalResp] = + couch_query_servers:ddoc_prompt(DDoc, [<<"shows">>, ShowName], + [JsonDoc, JsonReq]), + JsonResp = apply_etag(ExternalResp, CurrentEtag), + chttpd_external:send_external_response(Req, JsonResp) + end). + + +show_etag(#httpd{user_ctx=UserCtx}=Req, Doc, DDoc, More) -> + Accept = chttpd:header_value(Req, "Accept"), + DocPart = case Doc of + nil -> nil; + Doc -> chttpd:doc_etag(Doc) + end, + couch_httpd:make_etag({couch_httpd:doc_etag(DDoc), DocPart, Accept, + UserCtx#user_ctx.roles, More}). + +% /db/_design/foo/update/bar/docid +% updates a doc based on a request +% handle_doc_update_req(#httpd{method = 'GET'}=Req, _Db, _DDoc) -> +% % anything but GET +% send_method_not_allowed(Req, "POST,PUT,DELETE,ETC"); + +handle_doc_update_req(#httpd{ + path_parts=[_, _, _, _, UpdateName, DocId] + }=Req, Db, DDoc) -> + Doc = maybe_open_doc(Db, DocId), + send_doc_update_response(Req, Db, DDoc, UpdateName, Doc, DocId); + +handle_doc_update_req(#httpd{ + path_parts=[_, _, _, _, UpdateName] + }=Req, Db, DDoc) -> + send_doc_update_response(Req, Db, DDoc, UpdateName, nil, null); + +handle_doc_update_req(Req, _Db, _DDoc) -> + send_error(Req, 404, <<"update_error">>, <<"Invalid path.">>). + +send_doc_update_response(Req, Db, DDoc, UpdateName, Doc, DocId) -> + JsonReq = chttpd_external:json_req_obj(Req, Db, DocId), + JsonDoc = couch_query_servers:json_doc(Doc), + Cmd = [<<"updates">>, UpdateName], + case couch_query_servers:ddoc_prompt(DDoc, Cmd, [JsonDoc, JsonReq]) of + [<<"up">>, {NewJsonDoc}, JsonResp] -> + case chttpd:header_value(Req, "X-Couch-Full-Commit", "false") of + "true" -> + Options = [full_commit, {user_ctx, Req#httpd.user_ctx}]; + _ -> + Options = [{user_ctx, Req#httpd.user_ctx}] + end, + NewDoc = couch_doc:from_json_obj({NewJsonDoc}), + Code = 201, + {ok, _NewRev} = fabric:update_doc(Db, NewDoc, Options); + [<<"up">>, _Other, JsonResp] -> + Code = 200 + end, + JsonResp2 = json_apply_field({<<"code">>, Code}, JsonResp), + % todo set location field + chttpd_external:send_external_response(Req, JsonResp2). + + +% view-list request with view and list from same design doc. +handle_view_list_req(#httpd{method='GET', + path_parts=[_, _, DesignName, _, ListName, ViewName]}=Req, Db, DDoc) -> + handle_view_list(Req, Db, DDoc, ListName, {DesignName, ViewName}, nil); + +% view-list request with view and list from different design docs. +handle_view_list_req(#httpd{method='GET', + path_parts=[_, _, _, _, ListName, DesignName, ViewName]}=Req, Db, DDoc) -> + handle_view_list(Req, Db, DDoc, ListName, {DesignName, ViewName}, nil); + +handle_view_list_req(#httpd{method='GET'}=Req, _Db, _DDoc) -> + send_error(Req, 404, <<"list_error">>, <<"Invalid path.">>); + +handle_view_list_req(#httpd{method='POST', + path_parts=[_, _, DesignName, _, ListName, ViewName]}=Req, Db, DDoc) -> + ReqBody = couch_httpd:body(Req), + {Props2} = ?JSON_DECODE(ReqBody), + Keys = proplists:get_value(<<"keys">>, Props2, nil), + handle_view_list(Req#httpd{req_body=ReqBody}, Db, DDoc, ListName, + {DesignName, ViewName}, Keys); + +handle_view_list_req(#httpd{method='POST', + path_parts=[_, _, _, _, ListName, DesignName, ViewName]}=Req, Db, DDoc) -> + ReqBody = couch_httpd:body(Req), + {Props2} = ?JSON_DECODE(ReqBody), + Keys = proplists:get_value(<<"keys">>, Props2, nil), + handle_view_list(Req#httpd{req_body=ReqBody}, Db, DDoc, ListName, + {DesignName, ViewName}, Keys); + +handle_view_list_req(#httpd{method='POST'}=Req, _Db, _DDoc) -> + send_error(Req, 404, <<"list_error">>, <<"Invalid path.">>); + +handle_view_list_req(Req, _Db, _DDoc) -> + send_method_not_allowed(Req, "GET,POST,HEAD"). + +handle_view_list(Req, Db, DDoc, LName, {ViewDesignName, ViewName}, Keys) -> + {ok, VDoc} = fabric:open_doc(Db, <<"_design/", ViewDesignName/binary>>, []), + Group = couch_view_group:design_doc_to_view_group(Db, VDoc), + IsReduce = chttpd_view:get_reduce_type(Req), + ViewType = chttpd_view:extract_view_type(ViewName, Group#group.views, + IsReduce), + QueryArgs = chttpd_view:parse_view_params(Req, Keys, ViewType), + CB = fun list_callback/2, + Etag = couch_uuids:new(), + chttpd:etag_respond(Req, Etag, fun() -> + couch_query_servers:with_ddoc_proc(DDoc, fun(QServer) -> + Acc0 = #lacc{ + lname = LName, + req = Req, + qserver = QServer, + db = Db, + etag = Etag + }, + fabric:query_view(Db, VDoc, ViewName, CB, Acc0, QueryArgs) + end) + end). + +list_callback({total_and_offset, Total, Offset}, #lacc{resp=nil} = Acc) -> + start_list_resp({[{<<"total_rows">>, Total}, {<<"offset">>, Offset}]}, Acc); +list_callback({total_and_offset, _, _}, Acc) -> + % a sorted=false view where the message came in late. Ignore. + {ok, Acc}; +list_callback({row, Row}, #lacc{resp=nil} = Acc) -> + % first row of a reduce view, or a sorted=false view + {ok, NewAcc} = start_list_resp({[]}, Acc), + send_list_row(Row, NewAcc); +list_callback({row, Row}, Acc) -> + send_list_row(Row, Acc); +list_callback(complete, Acc) -> + #lacc{qserver = {Proc, _}, resp = Resp0} = Acc, + if Resp0 =:= nil -> + {ok, #lacc{resp = Resp}} = start_list_resp({[]}, Acc); + true -> + Resp = Resp0 + end, + [<<"end">>, Chunk] = couch_query_servers:proc_prompt(Proc, [<<"list_end">>]), + send_non_empty_chunk(Resp, Chunk), + couch_httpd:last_chunk(Resp), + {ok, Resp}; +list_callback({error, Reason}, {_, Resp}) -> + chttpd:send_chunked_error(Resp, {error, Reason}). + +start_list_resp(Head, Acc) -> + #lacc{ + req = Req, + db = Db, + qserver = QServer, + lname = LName, + etag = Etag + } = Acc, + + % use a separate process because we're already in a receive loop, and + % json_req_obj calls fabric:get_db_info() + spawn_monitor(fun() -> exit(chttpd_external:json_req_obj(Req, Db)) end), + receive {'DOWN', _, _, _, JsonReq} -> ok end, + + [<<"start">>,Chunk,JsonResp] = couch_query_servers:ddoc_proc_prompt(QServer, + [<<"lists">>, LName], [Head, JsonReq]), + JsonResp2 = apply_etag(JsonResp, Etag), + #extern_resp_args{ + code = Code, + ctype = CType, + headers = ExtHeaders + } = couch_httpd_external:parse_external_response(JsonResp2), + JsonHeaders = couch_httpd_external:default_or_content_type(CType, ExtHeaders), + {ok, Resp} = start_chunked_response(Req, Code, JsonHeaders), + send_non_empty_chunk(Resp, Chunk), + {ok, Acc#lacc{resp=Resp}}. + +send_list_row(Row, #lacc{qserver = {Proc, _}, resp = Resp} = Acc) -> + try couch_query_servers:proc_prompt(Proc, [<<"list_row">>, Row]) of + [<<"chunks">>, Chunk] -> + send_non_empty_chunk(Resp, Chunk), + {ok, Acc}; + [<<"end">>, Chunk] -> + send_non_empty_chunk(Resp, Chunk), + couch_httpd:last_chunk(Resp), + {stop, Resp} + catch Error -> + chttpd:send_chunked_error(Resp, Error), + {stop, Resp} + end. + +send_non_empty_chunk(_, []) -> + ok; +send_non_empty_chunk(Resp, Chunk) -> + send_chunk(Resp, Chunk). + +% Maybe this is in the proplists API +% todo move to couch_util +json_apply_field(H, {L}) -> + json_apply_field(H, L, []). +json_apply_field({Key, NewValue}, [{Key, _OldVal} | Headers], Acc) -> + % drop matching keys + json_apply_field({Key, NewValue}, Headers, Acc); +json_apply_field({Key, NewValue}, [{OtherKey, OtherVal} | Headers], Acc) -> + % something else is next, leave it alone. + json_apply_field({Key, NewValue}, Headers, [{OtherKey, OtherVal} | Acc]); +json_apply_field({Key, NewValue}, [], Acc) -> + % end of list, add ours + {[{Key, NewValue}|Acc]}. + +apply_etag({ExternalResponse}, CurrentEtag) -> + % Here we embark on the delicate task of replacing or creating the + % headers on the JsonResponse object. We need to control the Etag and + % Vary headers. If the external function controls the Etag, we'd have to + % run it to check for a match, which sort of defeats the purpose. + case couch_util:get_value(<<"headers">>, ExternalResponse, nil) of + nil -> + % no JSON headers + % add our Etag and Vary headers to the response + {[{<<"headers">>, {[{<<"Etag">>, CurrentEtag}, {<<"Vary">>, <<"Accept">>}]}} | ExternalResponse]}; + JsonHeaders -> + {[case Field of + {<<"headers">>, JsonHeaders} -> % add our headers + JsonHeadersEtagged = json_apply_field({<<"Etag">>, CurrentEtag}, JsonHeaders), + JsonHeadersVaried = json_apply_field({<<"Vary">>, <<"Accept">>}, JsonHeadersEtagged), + {<<"headers">>, JsonHeadersVaried}; + _ -> % skip non-header fields + Field + end || Field <- ExternalResponse]} + end. + |