blob: 9f54a56c0fcb590677e23bbceabcb8eaa3763240 [file] [log] [blame]
% 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(couch_index_updater).
-behaviour(gen_server).
%% API
-export([start_link/2, run/2, is_running/1, update/2, restart/2]).
%% gen_server callbacks
-export([init/1, terminate/2, code_change/3]).
-export([handle_call/3, handle_cast/2, handle_info/2]).
-include_lib("couch/include/couch_db.hrl").
-record(st, {
idx,
mod,
pid=nil
}).
start_link(Index, Module) ->
gen_server:start_link(?MODULE, {Index, Module}, []).
run(Pid, IdxState) ->
gen_server:call(Pid, {update, IdxState}).
is_running(Pid) ->
gen_server:call(Pid, is_running).
update(Mod, State) ->
update(nil, Mod, State).
restart(Pid, IdxState) ->
gen_server:call(Pid, {restart, IdxState}).
init({Index, Module}) ->
process_flag(trap_exit, true),
{ok, #st{idx=Index, mod=Module}}.
terminate(_Reason, State) ->
couch_util:shutdown_sync(State#st.pid),
ok.
handle_call({update, _IdxState}, _From, #st{pid=Pid}=State) when is_pid(Pid) ->
{reply, ok, State};
handle_call({update, IdxState}, _From, #st{idx=Idx, mod=Mod}=State) ->
Args = [Mod:get(db_name, IdxState), Mod:get(idx_name, IdxState)],
?LOG_INFO("Starting index update for db: ~s idx: ~s", Args),
Pid = spawn_link(fun() -> update(Idx, Mod, IdxState) end),
{reply, ok, State#st{pid=Pid}};
handle_call({restart, IdxState}, _From, #st{idx=Idx, mod=Mod}=State) ->
Args = [Mod:get(db_name, IdxState), Mod:get(idx_name, IdxState)],
?LOG_INFO("Restarting index update for db: ~s idx: ~s", Args),
case is_pid(State#st.pid) of
true -> couch_util:shutdown_sync(State#st.pid);
_ -> ok
end,
Pid = spawn_link(fun() -> update(Idx, State#st.mod, IdxState) end),
{reply, ok, State#st{pid=Pid}};
handle_call(is_running, _From, #st{pid=Pid}=State) when is_pid(Pid) ->
{reply, true, State};
handle_call(is_running, _From, State) ->
{reply, false, State}.
handle_cast(_Mesg, State) ->
{stop, unknown_cast, State}.
handle_info({'EXIT', _, {updated, Pid, IdxState}}, #st{pid=Pid}=State) ->
Mod = State#st.mod,
Args = [Mod:get(db_name, IdxState), Mod:get(idx_name, IdxState)],
?LOG_INFO("Index update finished for db: ~s idx: ~s", Args),
ok = gen_server:cast(State#st.idx, {updated, IdxState}),
{noreply, State#st{pid=undefined}};
handle_info({'EXIT', _, {reset, Pid}}, #st{idx=Idx, pid=Pid}=State) ->
{ok, NewIdxState} = gen_server:call(State#st.idx, reset),
Pid2 = spawn_link(fun() -> update(Idx, State#st.mod, NewIdxState) end),
{noreply, State#st{pid=Pid2}};
handle_info({'EXIT', Pid, normal}, #st{pid=Pid}=State) ->
{noreply, State#st{pid=undefined}};
handle_info({'EXIT', Pid, {{nocatch, Error}, _Trace}}, State) ->
handle_info({'EXIT', Pid, Error}, State);
handle_info({'EXIT', Pid, Error}, #st{pid=Pid}=State) ->
ok = gen_server:cast(State#st.idx, {update_error, Error}),
{noreply, State#st{pid=undefined}};
handle_info({'EXIT', Pid, _Reason}, #st{idx=Pid}=State) ->
{stop, normal, State};
handle_info({'EXIT', _Pid, normal}, State) ->
{noreply, State};
handle_info(_Mesg, State) ->
{stop, unknown_info, State}.
code_change(_OldVsn, State, _Extra) ->
{ok, State}.
update(Idx, Mod, IdxState) ->
DbName = Mod:get(db_name, IdxState),
CurrSeq = Mod:get(update_seq, IdxState),
UpdateOpts = Mod:get(update_options, IdxState),
CommittedOnly = lists:member(committed_only, UpdateOpts),
IncludeDesign = lists:member(include_design, UpdateOpts),
DocOpts = case lists:member(local_seq, UpdateOpts) of
true -> [conflicts, deleted_conflicts, local_seq];
_ -> [conflicts, deleted_conflicts]
end,
couch_util:with_db(DbName, fun(Db) ->
DbUpdateSeq = couch_db:get_update_seq(Db),
DbCommittedSeq = couch_db:get_committed_update_seq(Db),
PurgedIdxState = case purge_index(Db, Mod, IdxState) of
{ok, IdxState0} -> IdxState0;
reset -> exit({reset, self()})
end,
NumChanges = couch_db:count_changes_since(Db, CurrSeq),
LoadDoc = fun(DocInfo) ->
#doc_info{
id=DocId,
high_seq=Seq,
revs=[#rev_info{deleted=Deleted} | _]
} = DocInfo,
case {IncludeDesign, DocId} of
{false, <<"_design/", _/binary>>} ->
{nil, Seq};
_ when Deleted ->
{#doc{id=DocId, deleted=true}, Seq};
_ ->
{ok, Doc} = couch_db:open_doc_int(Db, DocInfo, DocOpts),
{Doc, Seq}
end
end,
Proc = fun(DocInfo, _, {IdxStateAcc, _}) ->
HighSeq = DocInfo#doc_info.high_seq,
case CommittedOnly and (HighSeq > DbCommittedSeq) of
true ->
{stop, {IdxStateAcc, false}};
false ->
{Doc, Seq} = LoadDoc(DocInfo),
{ok, NewSt} = Mod:process_doc(Doc, Seq, IdxStateAcc),
{ok, {NewSt, true}}
end
end,
{ok, InitIdxState} = Mod:start_update(Idx, PurgedIdxState, NumChanges),
Acc0 = {InitIdxState, true},
{ok, _, Acc} = couch_db:enum_docs_since(Db, CurrSeq, Proc, Acc0, []),
{ProcIdxSt, SendLast} = Acc,
% If we didn't bail due to hitting the last committed seq we need
% to send our last update_seq through.
{ok, LastIdxSt} = case SendLast of
true ->
Mod:process_doc(nil, DbUpdateSeq, ProcIdxSt);
_ ->
{ok, ProcIdxSt}
end,
{ok, FinalIdxState} = Mod:finish_update(LastIdxSt),
exit({updated, self(), FinalIdxState})
end).
purge_index(Db, Mod, IdxState) ->
DbPurgeSeq = couch_db:get_purge_seq(Db),
IdxPurgeSeq = Mod:get(purge_seq, IdxState),
if
DbPurgeSeq == IdxPurgeSeq ->
{ok, IdxState};
DbPurgeSeq == IdxPurgeSeq + 1 ->
{ok, PurgedIdRevs} = couch_db:get_last_purged(Db),
Mod:purge(Db, DbPurgeSeq, PurgedIdRevs, IdxState);
true ->
reset
end.