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Diffstat (limited to 'deps/fabric/src/fabric_view_all_docs.erl')
| -rw-r--r-- | deps/fabric/src/fabric_view_all_docs.erl | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/deps/fabric/src/fabric_view_all_docs.erl b/deps/fabric/src/fabric_view_all_docs.erl new file mode 100644 index 00000000..a769aedc --- /dev/null +++ b/deps/fabric/src/fabric_view_all_docs.erl @@ -0,0 +1,181 @@ +% Copyright 2010 Cloudant +% +% 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_all_docs). + +-export([go/4]). +-export([open_doc/3]). % exported for spawn + +-include("fabric.hrl"). +-include_lib("mem3/include/mem3.hrl"). +-include_lib("couch/include/couch_db.hrl"). + +go(DbName, #view_query_args{keys=nil} = QueryArgs, Callback, Acc0) -> + Workers = fabric_util:submit_jobs(mem3:shards(DbName),all_docs,[QueryArgs]), + BufferSize = couch_config:get("fabric", "map_buffer_size", "2"), + #view_query_args{limit = Limit, skip = Skip} = QueryArgs, + State = #collector{ + query_args = QueryArgs, + callback = Callback, + buffer_size = list_to_integer(BufferSize), + counters = fabric_dict:init(Workers, 0), + skip = Skip, + limit = Limit, + user_acc = Acc0 + }, + RexiMon = fabric_util:create_monitors(Workers), + try rexi_utils:recv(Workers, #shard.ref, fun handle_message/3, + State, infinity, 5000) 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; + + +go(DbName, QueryArgs, Callback, Acc0) -> + #view_query_args{ + direction = Dir, + include_docs = IncludeDocs, + limit = Limit0, + skip = Skip0, + keys = Keys + } = QueryArgs, + {_, Ref0} = spawn_monitor(fun() -> exit(fabric:get_doc_count(DbName)) end), + Monitors0 = [spawn_monitor(?MODULE, open_doc, [DbName, Id, IncludeDocs]) || + Id <- Keys], + Monitors = if Dir=:=fwd -> Monitors0; true -> lists:reverse(Monitors0) end, + receive {'DOWN', Ref0, _, _, {ok, TotalRows}} -> + {ok, Acc1} = Callback({total_and_offset, TotalRows, 0}, Acc0), + {ok, Acc2} = doc_receive_loop(Monitors, Skip0, Limit0, Callback, Acc1), + Callback(complete, Acc2) + after 10000 -> + Callback(timeout, Acc0) + 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{} = Row, {Worker, From}, State) -> + #collector{query_args = Args, counters = Counters0, rows = Rows0} = State, + Dir = Args#view_query_args.direction, + Rows = merge_row(Dir, Row#view_row{worker=Worker}, Rows0), + Counters1 = fabric_dict:update_counter(Worker, 1, Counters0), + State1 = State#collector{rows=Rows, counters=Counters1}, + State2 = fabric_view:maybe_pause_worker(Worker, From, State1), + fabric_view:maybe_send_row(State2); + +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, Row, Rows) -> + lists:keymerge(#view_row.id, [Row], Rows); +merge_row(rev, Row, Rows) -> + lists:rkeymerge(#view_row.id, [Row], Rows). + +doc_receive_loop([], _, _, _, Acc) -> + {ok, Acc}; +doc_receive_loop(_, _, 0, _, Acc) -> + {ok, Acc}; +doc_receive_loop([{Pid,Ref}|Rest], Skip, Limit, Callback, Acc) when Skip > 0 -> + receive {'DOWN', Ref, process, Pid, #view_row{}} -> + doc_receive_loop(Rest, Skip-1, Limit-1, Callback, Acc) + after 10000 -> + timeout + end; +doc_receive_loop([{Pid,Ref}|Rest], 0, Limit, Callback, AccIn) -> + receive {'DOWN', Ref, process, Pid, #view_row{} = Row} -> + case Callback(fabric_view:transform_row(Row), AccIn) of + {ok, Acc} -> + doc_receive_loop(Rest, 0, Limit-1, Callback, Acc); + {stop, Acc} -> + {ok, Acc} + end + after 10000 -> + timeout + end. + +open_doc(DbName, Id, IncludeDocs) -> + Row = case fabric:open_doc(DbName, Id, [deleted]) of + {not_found, missing} -> + Doc = undefined, + #view_row{key=Id}; + {ok, #doc{deleted=true, revs=Revs}} -> + Doc = null, + {RevPos, [RevId|_]} = Revs, + Value = {[{rev,couch_doc:rev_to_str({RevPos, RevId})}, {deleted,true}]}, + #view_row{key=Id, id=Id, value=Value}; + {ok, #doc{revs=Revs} = Doc0} -> + Doc = couch_doc:to_json_obj(Doc0, []), + {RevPos, [RevId|_]} = Revs, + Value = {[{rev,couch_doc:rev_to_str({RevPos, RevId})}]}, + #view_row{key=Id, id=Id, value=Value} + end, + exit(if IncludeDocs -> Row#view_row{doc=Doc}; true -> Row end). |