more work on mem3 init, handling different types of joins, requiring more human-intervention, reworking startargs to strip out most everything

6 files changed, 114 insertions, 79 deletions

diff --git a/ebin/dynomite.app b/ebin/dynomite.app
index b339496a..e6e71af2 100644
--- a/ebin/dynomite.app
+++ b/ebin/dynomite.app
@@ -18,6 +18,7 @@
       dynomite_prof,
       dynomite_sup,
       lib_misc,
+      mem3,
       mem_utils,
       membership2,
       node,
diff --git a/include/common.hrl b/include/common.hrl
index 608a23ad..6d92d9fa 100644
--- a/include/common.hrl
+++ b/include/common.hrl
@@ -44,4 +44,7 @@
 -record(mem, {header=3,
               node,
               nodes,
-              clock}).
+              clock,
+              ets,
+              test=false
+             }).
diff --git a/src/dynomite_app.erl b/src/dynomite_app.erl
index b31b2e57..417f4c76 100644
--- a/src/dynomite_app.erl
+++ b/src/dynomite_app.erl
@@ -40,17 +40,9 @@
 
 %% @doc start required apps, join cluster, start dynomite supervisor
 start(_Type, _StartArgs) ->
-    % get process_dict hack for startargs (i.e. not from .app file)
-    PdStartArgs = case erase(startargs) of
-    undefined ->
-        [];
-    Args ->
-        Args
-    end,
-
     % start dynomite supervisor
     ok = start_node(),
-    case dynomite_sup:start_link(PdStartArgs) of
+    case dynomite_sup:start_link() of
     {ok, Supervisor} ->
         {ok, Supervisor};
     Error ->
diff --git a/src/dynomite_sup.erl b/src/dynomite_sup.erl
index 1bf0de22..b60824ac 100644
--- a/src/dynomite_sup.erl
+++ b/src/dynomite_sup.erl
@@ -1,20 +1,10 @@
-%%%-------------------------------------------------------------------
-%%% File:      dynomite_sup.erl
-%%% @author    Cliff Moon <cliff@powerset.com> []
-%%% @copyright 2008 Cliff Moon
-%%% @doc
-%%%
-%%% @end
-%%%
-%%% @since 2008-06-27 by Cliff Moon
-%%%-------------------------------------------------------------------
 -module(dynomite_sup).
--author('cliff@powerset.com').
+-author('brad@cloudant.com').
 
 -behaviour(supervisor).
 
 %% API
--export([start_link/1]).
+-export([start_link/0]).
 
 %% Supervisor callbacks
 -export([init/1]).
@@ -31,8 +21,8 @@
 %% @doc Starts the supervisor
 %% @end
 %%--------------------------------------------------------------------
-start_link(Hints) ->
-    supervisor:start_link(?MODULE, [Hints]).
+start_link() ->
+    supervisor:start_link(?MODULE, []).
 
 %%====================================================================
 %% Supervisor callbacks
@@ -47,11 +37,9 @@ start_link(Hints) ->
 %% specifications.
 %% @end
 %%--------------------------------------------------------------------
-init(Args) ->
-    Node = node(),
-    Nodes = running_nodes() ++ [node()],
+init(_Args) ->
     Membership = {membership,
-                  {mem3, start_link, [Node, Nodes, Args]},
+                  {mem3, start_link, []},
                   permanent,
                   1000,
                   worker,
@@ -68,18 +56,3 @@ init(Args) ->
 %%====================================================================
 %% Internal functions
 %%====================================================================
-
-%% @doc get a list of running nodes visible to this local node
-running_nodes() ->
-    [Node || Node <- nodes([this,visible]), running(Node)].
-
-%% @doc monitor the membership server on Node from here
-running(Node) ->
-    Ref = erlang:monitor(process, {membership, Node}),
-    R = receive
-            {'DOWN', Ref, _, _, _} -> false
-        after 1 ->
-                true
-        end,
-    erlang:demonitor(Ref),
-    R.
diff --git a/src/mem3.erl b/src/mem3.erl
index 6f53ed23..1018af29 100644
--- a/src/mem3.erl
+++ b/src/mem3.erl
@@ -5,8 +5,8 @@
 -behaviour(gen_server).
 
 %% API
--export([start_link/2, start_link/3, stop/0, stop/1]).
--export([clock/0, state/0]).
+-export([start_link/0, start_link/1, stop/0, stop/1]).
+-export([join/2, clock/0, state/0]).
 
 %% gen_server callbacks
 -export([init/1, handle_call/3, handle_cast/2, handle_info/2,
@@ -21,12 +21,12 @@
 %% API
 %%====================================================================
 
-start_link(Node, ErlNodes) ->
-    start_link(Node, ErlNodes, []).
+start_link() ->
+    start_link([]).
 
 
-start_link(Node, ErlNodes, Args) ->
-    gen_server:start_link({local, ?MODULE}, ?MODULE, [Node, ErlNodes, Args], []).
+start_link(Args) ->
+    gen_server:start_link({local, ?MODULE}, ?MODULE, Args, []).
 
 
 stop() ->
@@ -37,6 +37,10 @@ stop(Server) ->
     gen_server:cast(Server, stop).
 
 
+join(JoinType, Nodes) ->
+    gen_server:call(?MODULE, {join, JoinType, Nodes}).
+
+
 clock() ->
     gen_server:call(?MODULE, clock).
 
@@ -50,20 +54,23 @@ state() ->
 %%====================================================================
 
 %% start up membership server
-init([Node, Nodes, Args]) ->
+init(Args) ->
     process_flag(trap_exit,true),
-    showroom_log:message(info, "membership: membership server starting...", []),
-    net_kernel:monitor_nodes(true),
-    Options = lists:flatten(Args),
     Config = configuration:get_config(),
-    OldState = read_latest_state_file(Config),
-    State = handle_init(Node, Nodes, Options, OldState, Config),
-    {ok, State}.
+    OldState = case Args of
+    test -> nil;
+    _ -> read_latest_state_file(Config)
+    end,
+    State = handle_init(OldState),
+    {ok, State#mem{test=(Args == test)}}.
+
 
 
 %% new node joining to this node
-handle_call({join, _JoiningNode, _Options}, _From, State) ->
-    {reply, ok, State};
+handle_call({join, JoinType, ExtNodes}, _From, State) ->
+    Config = configuration:get_config(),
+    Reply = handle_join(JoinType, ExtNodes, State, Config),
+    {reply, Reply, State};
 
 %% clock
 handle_call(clock, _From, State = #mem{clock=Clock}) ->
@@ -114,7 +121,7 @@ terminate(_Reason, _State) ->
 
 % ignored code change
 code_change(OldVsn, State, _Extra) ->
-    io:format("Unknown Old Version!~nOldVsn: ~p~nState : ~p~n", [OldVsn, State]),
+    io:format("Unknown Old Version~nOldVsn: ~p~nState : ~p~n", [OldVsn, State]),
     {ok, State}.
 
 
@@ -122,35 +129,50 @@ code_change(OldVsn, State, _Extra) ->
 %%% Internal functions
 %%--------------------------------------------------------------------
 
-% we could be:
-%  1. starting fresh node into a fresh cluster (we're one of first nodes)
-%  2. starting fresh node into an existing cluster (need to join)
-%  3. rejoining a cluster after some downtime
+% we could be automatically:
+%  1. rejoining a cluster after some downtime
+%
+% we could be manually:
+%  2. beginning a cluster with only this node
+%  3. joining a cluster as a new node
 %  4. replacing a node in an existing cluster
 
-handle_init(Node, [], nil, Options, Config) ->
-    % no other erlang nodes, no old state
-    Hints = proplists:get_value(hints, Options),
-    Map = create_map(Config, [{Node, Hints}]),
-    ?debugFmt("~nmap: ~p~n", [Map]);
-
-handle_init(_Node, [], _OldState, _Options, _Config) ->
-    % no other erlang nodes, old state
-    % network partition?
+handle_init(nil) ->
+    showroom_log:message(info, "membership: membership server starting...", []),
+    net_kernel:monitor_nodes(true),
+    Table = init_ets_table(),
+    Node = node(),
+    Nodes = [{Node, []}],
+    Clock = vector_clock:create(Node),
+    #mem{node=Node, nodes=Nodes, clock=Clock, ets=Table};
+
+handle_init(_OldState) ->
+    ?debugHere,
+    % there's an old state, let's try to rejoin automatically
+    % TODO implement me
+    Table = init_ets_table(),
+    #mem{ets=Table}.
+
+
+%% handle join activities
+handle_join(first, ExtNodes, State, Config) ->
+    Map = create_map(Config, ExtNodes),
+    ?debugFmt("~nmap: ~p~n", [Map]),
+    State#mem{};
+
+handle_join(new, _ExtNodes, _State, _Config) ->
     ok;
 
-handle_init(_Node, _ErlNodes, nil, _Options, _Config) ->
-    % other erlang nodes, no old state
+handle_join(replace, [_OldNode | _], _State, _Config) ->
     ok;
 
-handle_init(_Node, _ErlNodes, _OldState, _Options, _Config) ->
-    % other erlang nodes, old state
-    % network partition?
-    ok.
+handle_join(JoinType, _, _, _) ->
+    showroom_log:message(info, "membership: unknown join type: ~p", [JoinType]),
+    {error, {unknown_join_type, JoinType}}.
 
 
+%% @doc find the latest state file on disk
 find_latest_state_filename(Config) ->
-    ?debugFmt("~nConfig: ~p~n", [Config]),
     Dir = Config#config.directory,
     case file:list_dir(Dir) of
     {ok, Filenames} ->
@@ -202,3 +224,9 @@ make_fullmap(PMap) ->
         [{Node, Part, primary} | PartnerList]
     end, PMap),
   NodeParts.
+
+
+init_ets_table() ->
+    Table = list_to_atom(lists:concat(["mem_", atom_to_list(node())])),
+    ets:new(Table, [public, set, named_table]),
+    Table.
diff --git a/test/mem3_test.erl b/test/mem3_test.erl
new file mode 100644
index 00000000..6286936e
--- /dev/null
+++ b/test/mem3_test.erl
@@ -0,0 +1,38 @@
+-module(mem3_test).
+
+-include("../include/common.hrl").
+-include_lib("eunit/include/eunit.hrl").
+
+%% TEST SETUP
+
+all_tests_test_() ->
+    {"membership3 tests",
+     [
+      {setup,
+       fun test_setup/0,
+       fun test_teardown/1,
+       fun(Pid) ->
+           {with, Pid,
+            [
+             fun init/1
+            ]}
+       end}
+     ]
+    }.
+
+
+test_setup() ->
+    {ok, Pid} = mem3:start_link(test),
+    Pid.
+
+
+test_teardown(Pid) ->
+    exit(Pid, shutdown).
+
+
+%% TESTS
+
+init(_Pid) ->
+    State = #mem{test=Test} = mem3:state(),
+    ?debugFmt("~nState: ~p~n", [State]),
+    ?assertEqual(true, Test).