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authorAdam Kocoloski <adam@cloudant.com>2010-10-25 15:46:05 -0400
committerAdam Kocoloski <adam@cloudant.com>2010-10-25 21:45:32 -0400
commitebac05f686b56791511cb9b599dfb5a742dcfc96 (patch)
tree00a789cd058f98fa014d927f094f9e6e9f91f6f2 /apps/mem3/src/mem3_nodes.erl
parent952a85381ff4b5b34426000b1dee73c9e74becdd (diff)
use get-deps to pull down individual cloudant projects
Diffstat (limited to 'apps/mem3/src/mem3_nodes.erl')
-rw-r--r--apps/mem3/src/mem3_nodes.erl134
1 files changed, 0 insertions, 134 deletions
diff --git a/apps/mem3/src/mem3_nodes.erl b/apps/mem3/src/mem3_nodes.erl
deleted file mode 100644
index f9320598..00000000
--- a/apps/mem3/src/mem3_nodes.erl
+++ /dev/null
@@ -1,134 +0,0 @@
-% 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(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,
- erlang:send_after(5000, self(), 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}.