diff options
Diffstat (limited to 'deps/fabric/src/fabric_doc_missing_revs.erl')
-rw-r--r-- | deps/fabric/src/fabric_doc_missing_revs.erl | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/deps/fabric/src/fabric_doc_missing_revs.erl b/deps/fabric/src/fabric_doc_missing_revs.erl new file mode 100644 index 00000000..2dd04a70 --- /dev/null +++ b/deps/fabric/src/fabric_doc_missing_revs.erl @@ -0,0 +1,90 @@ +% 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_doc_missing_revs). + +-export([go/2, go/3]). + +-include("fabric.hrl"). +-include_lib("mem3/include/mem3.hrl"). + +go(DbName, AllIdsRevs) -> + go(DbName, AllIdsRevs, []). + +go(DbName, AllIdsRevs, Options) -> + Workers = lists:map(fun({#shard{name=Name, node=Node} = Shard, IdsRevs}) -> + Ref = rexi:cast(Node, {fabric_rpc, get_missing_revs, [Name, IdsRevs, + Options]}), + Shard#shard{ref=Ref} + end, group_idrevs_by_shard(DbName, AllIdsRevs)), + ResultDict = dict:from_list([{Id, {{nil,Revs},[]}} || {Id, Revs} <- AllIdsRevs]), + RexiMon = fabric_util:create_monitors(Workers), + Acc0 = {length(Workers), ResultDict, Workers}, + try + fabric_util:recv(Workers, #shard.ref, fun handle_message/3, Acc0) + after + rexi_monitor:stop(RexiMon) + end. + +handle_message({rexi_DOWN, _, {_,NodeRef},_}, _Shard, {_WorkerLen, ResultDict, Workers}) -> + NewWorkers = [W || #shard{node=Node} = W <- Workers, Node =/= NodeRef], + skip_message({fabric_dict:size(NewWorkers), ResultDict, NewWorkers}); +handle_message({rexi_EXIT, _}, Worker, {W, D, Workers}) -> + skip_message({W-1,D,lists:delete(Worker, Workers)}); +handle_message({ok, Results}, _Worker, {1, D0, _}) -> + D = update_dict(D0, Results), + {stop, dict:fold(fun force_reply/3, [], D)}; +handle_message({ok, Results}, Worker, {WaitingCount, D0, Workers}) -> + D = update_dict(D0, Results), + case dict:fold(fun maybe_reply/3, {stop, []}, D) of + continue -> + % still haven't heard about some Ids + {ok, {WaitingCount - 1, D, lists:delete(Worker,Workers)}}; + {stop, FinalReply} -> + % finished, stop the rest of the jobs + fabric_util:cleanup(lists:delete(Worker,Workers)), + {stop, FinalReply} + end. + +force_reply(Id, {{nil,Revs}, Anc}, Acc) -> + % never heard about this ID, assume it's missing + [{Id, Revs, Anc} | Acc]; +force_reply(_, {[], _}, Acc) -> + Acc; +force_reply(Id, {Revs, Anc}, Acc) -> + [{Id, Revs, Anc} | Acc]. + +maybe_reply(_, _, continue) -> + continue; +maybe_reply(_, {{nil, _}, _}, _) -> + continue; +maybe_reply(_, {[], _}, {stop, Acc}) -> + {stop, Acc}; +maybe_reply(Id, {Revs, Anc}, {stop, Acc}) -> + {stop, [{Id, Revs, Anc} | Acc]}. + +group_idrevs_by_shard(DbName, IdsRevs) -> + dict:to_list(lists:foldl(fun({Id, Revs}, D0) -> + lists:foldl(fun(Shard, D1) -> + dict:append(Shard, {Id, Revs}, D1) + end, D0, mem3:shards(DbName,Id)) + end, dict:new(), IdsRevs)). + +update_dict(D0, KVs) -> + lists:foldl(fun({K,V,A}, D1) -> dict:store(K, {V,A}, D1) end, D0, KVs). + +skip_message({0, Dict, _Workers}) -> + {stop, dict:fold(fun force_reply/3, [], Dict)}; +skip_message(Acc) -> + {ok, Acc}. |