| % 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(fabric_view_map). |
| |
| -export([go/6]). |
| |
| -include_lib("fabric/include/fabric.hrl"). |
| -include_lib("mem3/include/mem3.hrl"). |
| -include_lib("couch/include/couch_db.hrl"). |
| -include_lib("couch_mrview/include/couch_mrview.hrl"). |
| |
| go(DbName, GroupId, View, Args, Callback, Acc0) when is_binary(GroupId) -> |
| {ok, DDoc} = fabric:open_doc(DbName, <<"_design/", GroupId/binary>>, []), |
| go(DbName, DDoc, View, Args, Callback, Acc0); |
| |
| go(DbName, DDoc, View, Args, Callback, Acc0) -> |
| Shards = fabric_view:get_shards(DbName, Args), |
| Workers = fabric_util:submit_jobs(Shards, map_view, [DDoc, View, Args]), |
| #mrargs{limit = Limit, skip = Skip, keys = Keys} = Args, |
| State = #collector{ |
| db_name=DbName, |
| query_args = Args, |
| callback = Callback, |
| counters = fabric_dict:init(Workers, 0), |
| skip = Skip, |
| limit = Limit, |
| keys = fabric_view:keydict(Keys), |
| sorted = Args#mrargs.sorted, |
| user_acc = Acc0 |
| }, |
| RexiMon = fabric_util:create_monitors(Workers), |
| try rexi_utils:recv(Workers, #shard.ref, fun handle_message/3, |
| State, infinity, 1000 * 60 * 60) of |
| {ok, NewState} -> |
| {ok, NewState#collector.user_acc}; |
| {timeout, NewState} -> |
| Callback({error, timeout}, NewState#collector.user_acc); |
| {error, Resp} -> |
| {ok, Resp} |
| after |
| rexi_monitor:stop(RexiMon), |
| fabric_util:cleanup(Workers) |
| end. |
| |
| handle_message({rexi_DOWN, _, {_, NodeRef}, _}, _, State) -> |
| fabric_view:remove_down_shards(State, NodeRef); |
| |
| handle_message({rexi_EXIT, Reason}, Worker, State) -> |
| #collector{callback=Callback, counters=Counters0, user_acc=Acc} = State, |
| Counters = fabric_dict:erase(Worker, Counters0), |
| case fabric_view:is_progress_possible(Counters) of |
| true -> |
| {ok, State#collector{counters = Counters}}; |
| false -> |
| {ok, Resp} = Callback({error, fabric_util:error_info(Reason)}, Acc), |
| {error, Resp} |
| end; |
| |
| handle_message({total_and_offset, Tot, Off}, {Worker, From}, State) -> |
| #collector{ |
| callback = Callback, |
| counters = Counters0, |
| total_rows = Total0, |
| offset = Offset0, |
| user_acc = AccIn |
| } = State, |
| case fabric_dict:lookup_element(Worker, Counters0) of |
| undefined -> |
| % this worker lost the race with other partition copies, terminate |
| gen_server:reply(From, stop), |
| {ok, State}; |
| 0 -> |
| gen_server:reply(From, ok), |
| Counters1 = fabric_dict:update_counter(Worker, 1, Counters0), |
| Counters2 = fabric_view:remove_overlapping_shards(Worker, Counters1), |
| Total = Total0 + Tot, |
| Offset = Offset0 + Off, |
| case fabric_dict:any(0, Counters2) of |
| true -> |
| {ok, State#collector{ |
| counters = Counters2, |
| total_rows = Total, |
| offset = Offset |
| }}; |
| false -> |
| FinalOffset = erlang:min(Total, Offset+State#collector.skip), |
| {Go, Acc} = Callback({total_and_offset, Total, FinalOffset}, AccIn), |
| {Go, State#collector{ |
| counters = fabric_dict:decrement_all(Counters2), |
| total_rows = Total, |
| offset = FinalOffset, |
| user_acc = Acc |
| }} |
| end |
| end; |
| |
| handle_message(#view_row{}, {_, _}, #collector{limit=0} = State) -> |
| #collector{callback=Callback} = State, |
| {_, Acc} = Callback(complete, State#collector.user_acc), |
| {stop, State#collector{user_acc=Acc}}; |
| |
| handle_message(#view_row{} = Row, {_,From}, #collector{sorted=false} = St) -> |
| #collector{callback=Callback, user_acc=AccIn, limit=Limit} = St, |
| {Go, Acc} = Callback(fabric_view:transform_row(Row), AccIn), |
| rexi:stream_ack(From), |
| {Go, St#collector{user_acc=Acc, limit=Limit-1}}; |
| |
| handle_message(#view_row{} = Row, {Worker, From}, State) -> |
| #collector{ |
| query_args = #mrargs{direction=Dir}, |
| counters = Counters0, |
| rows = Rows0, |
| keys = KeyDict |
| } = State, |
| Rows = merge_row(Dir, KeyDict, Row#view_row{worker={Worker, From}}, Rows0), |
| Counters1 = fabric_dict:update_counter(Worker, 1, Counters0), |
| State1 = State#collector{rows=Rows, counters=Counters1}, |
| fabric_view:maybe_send_row(State1); |
| |
| handle_message(complete, Worker, State) -> |
| Counters = fabric_dict:update_counter(Worker, 1, State#collector.counters), |
| fabric_view:maybe_send_row(State#collector{counters = Counters}). |
| |
| merge_row(fwd, undefined, Row, Rows) -> |
| lists:merge(fun(#view_row{key=KeyA, id=IdA}, #view_row{key=KeyB, id=IdB}) -> |
| couch_view:less_json([KeyA, IdA], [KeyB, IdB]) |
| end, [Row], Rows); |
| merge_row(rev, undefined, Row, Rows) -> |
| lists:merge(fun(#view_row{key=KeyA, id=IdA}, #view_row{key=KeyB, id=IdB}) -> |
| couch_view:less_json([KeyB, IdB], [KeyA, IdA]) |
| end, [Row], Rows); |
| merge_row(_, KeyDict, Row, Rows) -> |
| lists:merge(fun(#view_row{key=A, id=IdA}, #view_row{key=B, id=IdB}) -> |
| if A =:= B -> IdA < IdB; true -> |
| dict:fetch(A, KeyDict) < dict:fetch(B, KeyDict) |
| end |
| end, [Row], Rows). |