diff options
Diffstat (limited to 'src/mem3_nodes.erl')
-rw-r--r-- | src/mem3_nodes.erl | 120 |
1 files changed, 0 insertions, 120 deletions
diff --git a/src/mem3_nodes.erl b/src/mem3_nodes.erl deleted file mode 100644 index 6cbf3d9a..00000000 --- a/src/mem3_nodes.erl +++ /dev/null @@ -1,120 +0,0 @@ --module(mem3_nodes). --behaviour(gen_server). --export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2, - code_change/3]). - --export([start_link/0, get_nodelist/0]). - --include("mem3.hrl"). --include_lib("couch/include/couch_db.hrl"). - --record(state, {changes_pid, update_seq, nodes}). - -start_link() -> - gen_server:start_link({local, ?MODULE}, ?MODULE, [], []). - -get_nodelist() -> - gen_server:call(?MODULE, get_nodelist). - -init([]) -> - {Nodes, UpdateSeq} = initialize_nodelist(), - {Pid, _} = spawn_monitor(fun() -> listen_for_changes(UpdateSeq) end), - {ok, #state{changes_pid = Pid, update_seq = UpdateSeq, nodes = Nodes}}. - -handle_call(get_nodelist, _From, State) -> - {reply, State#state.nodes, State}; -handle_call({add_node, Node}, _From, #state{nodes=Nodes} = State) -> - gen_event:notify(mem3_events, {add_node, Node}), - {reply, ok, State#state{nodes = lists:umerge([Node], Nodes)}}; -handle_call({remove_node, Node}, _From, #state{nodes=Nodes} = State) -> - gen_event:notify(mem3_events, {remove_node, Node}), - {reply, ok, State#state{nodes = lists:delete(Node, Nodes)}}; -handle_call(_Call, _From, State) -> - {noreply, State}. - -handle_cast(_Msg, State) -> - {noreply, State}. - -handle_info({'DOWN', _, _, Pid, Reason}, #state{changes_pid=Pid} = State) -> - ?LOG_INFO("~p changes listener died ~p", [?MODULE, Reason]), - StartSeq = State#state.update_seq, - Seq = case Reason of {seq, EndSeq} -> EndSeq; _ -> StartSeq end, - timer:send_after(5000, start_listener), - {noreply, State#state{update_seq = Seq}}; -handle_info(start_listener, #state{update_seq = Seq} = State) -> - {NewPid, _} = spawn_monitor(fun() -> listen_for_changes(Seq) end), - {noreply, State#state{changes_pid=NewPid}}; -handle_info(_Info, State) -> - {noreply, State}. - -terminate(_Reason, _State) -> - ok. - -code_change(_OldVsn, State, _Extra) -> - {ok, State}. - -%% internal functions - -initialize_nodelist() -> - DbName = couch_config:get("mem3", "nodedb", "nodes"), - {ok, Db} = ensure_exists(DbName), - {ok, _, Nodes0} = couch_btree:fold(Db#db.id_tree, fun first_fold/3, [], []), - % add self if not already present - case lists:member(node(), Nodes0) of - true -> - Nodes = Nodes0; - false -> - Doc = #doc{id = couch_util:to_binary(node())}, - {ok, _} = couch_db:update_doc(Db, Doc, []), - Nodes = [node() | Nodes0] - end, - couch_db:close(Db), - {lists:sort(Nodes), Db#db.update_seq}. - -first_fold(#full_doc_info{id = <<"_design/", _/binary>>}, _, Acc) -> - {ok, Acc}; -first_fold(#full_doc_info{deleted=true}, _, Acc) -> - {ok, Acc}; -first_fold(#full_doc_info{id=Id}, _, Acc) -> - {ok, [mem3_util:to_atom(Id) | Acc]}. - -listen_for_changes(Since) -> - DbName = ?l2b(couch_config:get("mem3", "nodedb", "nodes")), - {ok, Db} = ensure_exists(DbName), - Args = #changes_args{ - feed = "continuous", - since = Since, - heartbeat = true, - include_docs = true - }, - ChangesFun = couch_changes:handle_changes(Args, nil, Db), - ChangesFun(fun changes_callback/2). - -ensure_exists(DbName) when is_list(DbName) -> - ensure_exists(list_to_binary(DbName)); -ensure_exists(DbName) -> - Options = [{user_ctx, #user_ctx{roles=[<<"_admin">>]}}], - case couch_db:open(DbName, Options) of - {ok, Db} -> - {ok, Db}; - _ -> - couch_server:create(DbName, Options) - end. - -changes_callback(start, _) -> - {ok, nil}; -changes_callback({stop, EndSeq}, _) -> - exit({seq, EndSeq}); -changes_callback({change, {Change}, _}, _) -> - Node = couch_util:get_value(<<"id">>, Change), - case Node of <<"_design/", _/binary>> -> ok; _ -> - case couch_util:get_value(deleted, Change, false) of - false -> - gen_server:call(?MODULE, {add_node, mem3_util:to_atom(Node)}); - true -> - gen_server:call(?MODULE, {remove_node, mem3_util:to_atom(Node)}) - end - end, - {ok, couch_util:get_value(<<"seq">>, Change)}; -changes_callback(timeout, _) -> - {ok, nil}. |