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Diffstat (limited to 'src/fabric/src/fabric_view.erl')
| -rw-r--r-- | src/fabric/src/fabric_view.erl | 478 |
1 files changed, 0 insertions, 478 deletions
diff --git a/src/fabric/src/fabric_view.erl b/src/fabric/src/fabric_view.erl deleted file mode 100644 index 425f864c4..000000000 --- a/src/fabric/src/fabric_view.erl +++ /dev/null @@ -1,478 +0,0 @@ -% 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). - --export([remove_overlapping_shards/2, maybe_send_row/1, - transform_row/1, keydict/1, extract_view/4, get_shards/2, - check_down_shards/2, handle_worker_exit/3, - get_shard_replacements/2, maybe_update_others/5]). --export([fix_skip_and_limit/1]). - --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"). - -%% @doc Check if a downed node affects any of our workers --spec check_down_shards(#collector{}, node()) -> - {ok, #collector{}} | {error, any()}. -check_down_shards(Collector, BadNode) -> - #collector{callback=Callback, counters=Counters, user_acc=Acc} = Collector, - Filter = fun(#shard{node = Node}, _) -> Node == BadNode end, - BadCounters = fabric_dict:filter(Filter, Counters), - case fabric_dict:size(BadCounters) > 0 of - true -> - Reason = {nodedown, <<"progress not possible">>}, - Callback({error, Reason}, Acc), - {error, Reason}; - false -> - {ok, Collector} - end. - -%% @doc Handle a worker that dies during a stream --spec handle_worker_exit(#collector{}, #shard{}, any()) -> {error, any()}. -handle_worker_exit(Collector, _Worker, Reason) -> - #collector{callback=Callback, user_acc=Acc} = Collector, - {ok, Resp} = Callback({error, fabric_util:error_info(Reason)}, Acc), - {error, Resp}. - - --spec remove_overlapping_shards(#shard{}, [{#shard{}, any()}]) -> - [{#shard{}, any()}]. -remove_overlapping_shards(#shard{} = Shard, Counters) -> - remove_overlapping_shards(Shard, Counters, fun stop_worker/1). - - --spec remove_overlapping_shards(#shard{}, [{#shard{}, any()}], fun()) -> - [{#shard{}, any()}]. -remove_overlapping_shards(#shard{} = Shard, Counters, RemoveCb) -> - Counters1 = filter_exact_copies(Shard, Counters, RemoveCb), - filter_possible_overlaps(Shard, Counters1, RemoveCb). - - -filter_possible_overlaps(Shard, Counters, RemoveCb) -> - Ranges0 = fabric_util:worker_ranges(Counters), - #shard{range = [BShard, EShard]} = Shard, - Ranges = Ranges0 ++ [{BShard, EShard}], - {Bs, Es} = lists:unzip(Ranges), - {MinB, MaxE} = {lists:min(Bs), lists:max(Es)}, - % Use a custom sort function which prioritizes the given shard - % range when the start endpoints match. - SortFun = fun - ({B, E}, {B, _}) when {B, E} =:= {BShard, EShard} -> - % If start matches with the shard's start, shard always wins - true; - ({B, _}, {B, E}) when {B, E} =:= {BShard, EShard} -> - % If start matches with the shard's start, shard always wins - false; - ({B, E1}, {B, E2}) -> - % If start matches, pick the longest range first - E2 >= E1; - ({B1, _}, {B2, _}) -> - % Then, by default, sort by start point - B1 =< B2 - end, - Ring = mem3_util:get_ring(Ranges, SortFun, MinB, MaxE), - fabric_dict:filter(fun - (S, _) when S =:= Shard -> - % Keep the original shard - true; - (#shard{range = [B, E]} = S, _) -> - case lists:member({B, E}, Ring) of - true -> - true; % Keep it - false -> - % Duplicate range, delete after calling callback function - case is_function(RemoveCb) of - true -> RemoveCb(S); - false -> ok - end, - false - end - end, Counters). - - -filter_exact_copies(#shard{range = Range0} = Shard0, Shards, Cb) -> - fabric_dict:filter(fun - (Shard, _) when Shard =:= Shard0 -> - true; % Don't remove ourselves - (#shard{range = Range} = Shard, _) when Range =:= Range0 -> - case is_function(Cb) of - true -> Cb(Shard); - false -> ok - end, - false; - (_, _) -> - true - end, Shards). - - -stop_worker(#shard{ref = Ref, node = Node}) -> - rexi:kill(Node, Ref). - - -maybe_send_row(#collector{limit=0} = State) -> - #collector{counters=Counters, user_acc=AccIn, callback=Callback} = State, - case fabric_dict:any(0, Counters) of - true -> - % we still need to send the total/offset header - {ok, State}; - false -> - erase(meta_sent), - {_, Acc} = Callback(complete, AccIn), - {stop, State#collector{user_acc=Acc}} - end; -maybe_send_row(State) -> - #collector{ - callback = Callback, - counters = Counters, - skip = Skip, - limit = Limit, - user_acc = AccIn - } = State, - case fabric_dict:any(0, Counters) of - true -> - {ok, State}; - false -> - try get_next_row(State) of - {_, NewState} when Skip > 0 -> - maybe_send_row(NewState#collector{skip=Skip-1}); - {Row0, NewState} -> - Row1 = possibly_embed_doc(NewState, Row0), - Row2 = detach_partition(Row1), - Row3 = transform_row(Row2), - case Callback(Row3, AccIn) of - {stop, Acc} -> - {stop, NewState#collector{user_acc=Acc, limit=Limit-1}}; - {ok, Acc} -> - maybe_send_row(NewState#collector{user_acc=Acc, limit=Limit-1}) - end - catch complete -> - erase(meta_sent), - {_, Acc} = Callback(complete, AccIn), - {stop, State#collector{user_acc=Acc}} - end - end. - -%% if include_docs=true is used when keys and -%% the values contain "_id" then use the "_id"s -%% to retrieve documents and embed in result -possibly_embed_doc(_State, - #view_row{id=reduced}=Row) -> - Row; -possibly_embed_doc(_State, - #view_row{value=undefined}=Row) -> - Row; -possibly_embed_doc(#collector{db_name=DbName, query_args=Args}, - #view_row{key=_Key, id=_Id, value=Value, doc=_Doc}=Row) -> - #mrargs{include_docs=IncludeDocs} = Args, - case IncludeDocs andalso is_tuple(Value) of - true -> - {Props} = Value, - Rev0 = couch_util:get_value(<<"_rev">>, Props), - case couch_util:get_value(<<"_id">>,Props) of - null -> Row#view_row{doc=null}; - undefined -> Row; - IncId -> - % use separate process to call fabric:open_doc - % to not interfere with current call - {Pid, Ref} = spawn_monitor(fun() -> - exit( - case Rev0 of - undefined -> - case fabric:open_doc(DbName, IncId, []) of - {ok, NewDoc} -> - Row#view_row{doc=couch_doc:to_json_obj(NewDoc,[])}; - {not_found, _} -> - Row#view_row{doc=null}; - Else -> - Row#view_row{doc={error, Else}} - end; - Rev0 -> - Rev = couch_doc:parse_rev(Rev0), - case fabric:open_revs(DbName, IncId, [Rev], []) of - {ok, [{ok, NewDoc}]} -> - Row#view_row{doc=couch_doc:to_json_obj(NewDoc,[])}; - {ok, [{{not_found, _}, Rev}]} -> - Row#view_row{doc=null}; - Else -> - Row#view_row{doc={error, Else}} - end - end) end), - receive {'DOWN',Ref,process,Pid, Resp} -> - Resp - end - end; - _ -> Row - end. - -detach_partition(#view_row{key={p, _Partition, Key}} = Row) -> - Row#view_row{key = Key}; -detach_partition(#view_row{} = Row) -> - Row. - -keydict(undefined) -> - undefined; -keydict(Keys) -> - {Dict,_} = lists:foldl(fun(K, {D,I}) -> {dict:store(K,I,D), I+1} end, - {dict:new(),0}, Keys), - Dict. - -%% internal %% - -get_next_row(#collector{rows = []}) -> - throw(complete); -get_next_row(#collector{reducer = RedSrc} = St) when RedSrc =/= undefined -> - #collector{ - query_args = #mrargs{direction = Dir}, - keys = Keys, - rows = RowDict, - lang = Lang, - counters = Counters0, - collation = Collation - } = St, - {Key, RestKeys} = find_next_key(Keys, Dir, Collation, RowDict), - case dict:find(Key, RowDict) of - {ok, Records} -> - NewRowDict = dict:erase(Key, RowDict), - Counters = lists:foldl(fun(#view_row{worker={Worker,From}}, CntrsAcc) -> - case From of - {Pid, _} when is_pid(Pid) -> - gen_server:reply(From, ok); - Pid when is_pid(Pid) -> - rexi:stream_ack(From) - end, - fabric_dict:update_counter(Worker, -1, CntrsAcc) - end, Counters0, Records), - Wrapped = [[V] || #view_row{value=V} <- Records], - {ok, [Reduced]} = couch_query_servers:rereduce(Lang, [RedSrc], Wrapped), - {ok, Finalized} = couch_query_servers:finalize(RedSrc, Reduced), - NewSt = St#collector{keys=RestKeys, rows=NewRowDict, counters=Counters}, - {#view_row{key=Key, id=reduced, value=Finalized}, NewSt}; - error -> - get_next_row(St#collector{keys=RestKeys}) - end; -get_next_row(State) -> - #collector{rows = [Row|Rest], counters = Counters0} = State, - {Worker, From} = Row#view_row.worker, - rexi:stream_ack(From), - Counters1 = fabric_dict:update_counter(Worker, -1, Counters0), - {Row, State#collector{rows = Rest, counters=Counters1}}. - -%% TODO: rectify nil <-> undefined discrepancies -find_next_key(nil, Dir, Collation, RowDict) -> - find_next_key(undefined, Dir, Collation, RowDict); -find_next_key(undefined, Dir, Collation, RowDict) -> - CmpFun = fun(A, B) -> compare(Dir, Collation, A, B) end, - case lists:sort(CmpFun, dict:fetch_keys(RowDict)) of - [] -> - throw(complete); - [Key|_] -> - {Key, nil} - end; -find_next_key([], _, _, _) -> - throw(complete); -find_next_key([Key|Rest], _, _, _) -> - {Key, Rest}. - -transform_row(#view_row{value={[{reduce_overflow_error, Msg}]}}) -> - {row, [{key,null}, {id,error}, {value,reduce_overflow_error}, {reason,Msg}]}; -transform_row(#view_row{key=Key, id=reduced, value=Value}) -> - {row, [{key,Key}, {value,Value}]}; -transform_row(#view_row{key=Key, id=undefined}) -> - {row, [{key,Key}, {id,error}, {value,not_found}]}; -transform_row(#view_row{key=Key, id=Id, value=Value, doc=undefined}) -> - {row, [{id,Id}, {key,Key}, {value,Value}]}; -transform_row(#view_row{key=Key, id=_Id, value=_Value, doc={error,Reason}}) -> - {row, [{id,error}, {key,Key}, {value,Reason}]}; -transform_row(#view_row{key=Key, id=Id, value=Value, doc=Doc}) -> - {row, [{id,Id}, {key,Key}, {value,Value}, {doc,Doc}]}. - -compare(_, _, A, A) -> true; -compare(fwd, <<"raw">>, A, B) -> A < B; -compare(rev, <<"raw">>, A, B) -> B < A; -compare(fwd, _, A, B) -> couch_ejson_compare:less_json(A, B); -compare(rev, _, A, B) -> couch_ejson_compare:less_json(B, A). - -extract_view(Pid, ViewName, [], _ViewType) -> - couch_log:error("missing_named_view ~p", [ViewName]), - exit(Pid, kill), - exit(missing_named_view); -extract_view(Pid, ViewName, [View|Rest], ViewType) -> - case lists:member(ViewName, view_names(View, ViewType)) of - true -> - if ViewType == reduce -> - {index_of(ViewName, view_names(View, reduce)), View}; - true -> - View - end; - false -> - extract_view(Pid, ViewName, Rest, ViewType) - end. - -view_names(View, Type) when Type == red_map; Type == reduce -> - [Name || {Name, _} <- View#mrview.reduce_funs]; -view_names(View, map) -> - View#mrview.map_names. - -index_of(X, List) -> - index_of(X, List, 1). - -index_of(_X, [], _I) -> - not_found; -index_of(X, [X|_Rest], I) -> - I; -index_of(X, [_|Rest], I) -> - index_of(X, Rest, I+1). - -get_shards(Db, #mrargs{} = Args) -> - DbPartitioned = fabric_util:is_partitioned(Db), - Partition = couch_mrview_util:get_extra(Args, partition), - if DbPartitioned orelse Partition == undefined -> ok; true -> - throw({bad_request, <<"partition specified on non-partitioned db">>}) - end, - DbName = fabric:dbname(Db), - % Decide which version of mem3:shards/1,2 or - % mem3:ushards/1,2 to use for the current - % request. - case {Args#mrargs.stable, Partition} of - {true, undefined} -> - {mem3:ushards(DbName), []}; - {true, Partition} -> - Shards = mem3:ushards(DbName, couch_partition:shard_key(Partition)), - {Shards, [{any, Shards}]}; - {false, undefined} -> - {mem3:shards(DbName), []}; - {false, Partition} -> - Shards = mem3:shards(DbName, couch_partition:shard_key(Partition)), - {Shards, [{any, Shards}]} - end. - -maybe_update_others(DbName, DDoc, ShardsInvolved, ViewName, - #mrargs{update=lazy} = Args) -> - ShardsNeedUpdated = mem3:shards(DbName) -- ShardsInvolved, - lists:foreach(fun(#shard{node=Node, name=ShardName}) -> - rpc:cast(Node, fabric_rpc, update_mrview, [ShardName, DDoc, ViewName, Args]) - end, ShardsNeedUpdated); -maybe_update_others(_DbName, _DDoc, _ShardsInvolved, _ViewName, _Args) -> - ok. - -get_shard_replacements(DbName, UsedShards0) -> - % We only want to generate a replacements list from shards - % that aren't already used. - AllLiveShards = mem3:live_shards(DbName, [node() | nodes()]), - UsedShards = [S#shard{ref=undefined} || S <- UsedShards0], - get_shard_replacements_int(AllLiveShards -- UsedShards, UsedShards). - -get_shard_replacements_int(UnusedShards, UsedShards) -> - % If we have more than one copy of a range then we don't - % want to try and add a replacement to any copy. - RangeCounts = lists:foldl(fun(#shard{range=R}, Acc) -> - dict:update_counter(R, 1, Acc) - end, dict:new(), UsedShards), - - % For each seq shard range with a count of 1, find any - % possible replacements from the unused shards. The - % replacement list is keyed by range. - lists:foldl(fun(#shard{range = [B, E] = Range}, Acc) -> - case dict:find(Range, RangeCounts) of - {ok, 1} -> - Repls = mem3_util:non_overlapping_shards(UnusedShards, B, E), - % Only keep non-empty lists of replacements - if Repls == [] -> Acc; true -> - [{Range, Repls} | Acc] - end; - _ -> - Acc - end - end, [], UsedShards). - --spec fix_skip_and_limit(#mrargs{}) -> {CoordArgs::#mrargs{}, WorkerArgs::#mrargs{}}. -fix_skip_and_limit(#mrargs{} = Args) -> - {CoordArgs, WorkerArgs} = case couch_mrview_util:get_extra(Args, partition) of - undefined -> - #mrargs{skip=Skip, limit=Limit}=Args, - {Args, Args#mrargs{skip=0, limit=Skip+Limit}}; - _Partition -> - {Args#mrargs{skip=0}, Args} - end, - %% the coordinator needs to finalize each row, so make sure the shards don't - {CoordArgs, remove_finalizer(WorkerArgs)}. - -remove_finalizer(Args) -> - couch_mrview_util:set_extra(Args, finalizer, null). - - -remove_overlapping_shards_test() -> - Cb = undefined, - - Shards = mk_cnts([[0, 10], [11, 20], [21, ?RING_END]], 3), - - % Simple (exact) overlap - Shard1 = mk_shard("node-3", [11, 20]), - Shards1 = fabric_dict:store(Shard1, nil, Shards), - R1 = remove_overlapping_shards(Shard1, Shards1, Cb), - ?assertEqual([{0, 10}, {11, 20}, {21, ?RING_END}], - fabric_util:worker_ranges(R1)), - ?assert(fabric_dict:is_key(Shard1, R1)), - - % Split overlap (shard overlap multiple workers) - Shard2 = mk_shard("node-3", [0, 20]), - Shards2 = fabric_dict:store(Shard2, nil, Shards), - R2 = remove_overlapping_shards(Shard2, Shards2, Cb), - ?assertEqual([{0, 20}, {21, ?RING_END}], - fabric_util:worker_ranges(R2)), - ?assert(fabric_dict:is_key(Shard2, R2)). - - -get_shard_replacements_test() -> - Unused = [mk_shard(N, [B, E]) || {N, B, E} <- [ - {"n1", 11, 20}, {"n1", 21, ?RING_END}, - {"n2", 0, 4}, {"n2", 5, 10}, {"n2", 11, 20}, - {"n3", 0, 21, ?RING_END} - ]], - Used = [mk_shard(N, [B, E]) || {N, B, E} <- [ - {"n2", 21, ?RING_END}, - {"n3", 0, 10}, {"n3", 11, 20} - ]], - Res = lists:sort(get_shard_replacements_int(Unused, Used)), - % Notice that [0, 10] range can be replaced by spawning the [0, 4] and [5, - % 10] workers on n1 - Expect = [ - {[0, 10], [mk_shard("n2", [0, 4]), mk_shard("n2", [5, 10])]}, - {[11, 20], [mk_shard("n1", [11, 20]), mk_shard("n2", [11, 20])]}, - {[21, ?RING_END], [mk_shard("n1", [21, ?RING_END])]} - ], - ?assertEqual(Expect, Res). - - -mk_cnts(Ranges, NoNodes) -> - orddict:from_list([{Shard,nil} - || Shard <- - lists:flatten(lists:map( - fun(Range) -> - mk_shards(NoNodes,Range,[]) - end, Ranges))] - ). - -mk_shards(0,_Range,Shards) -> - Shards; -mk_shards(NoNodes,Range,Shards) -> - Name ="node-" ++ integer_to_list(NoNodes), - mk_shards(NoNodes-1,Range, [mk_shard(Name, Range) | Shards]). - - -mk_shard(Name, Range) -> - Node = list_to_atom(Name), - BName = list_to_binary(Name), - #shard{name = BName, node = Node, range = Range}. |