cosmetic: give rabbit.erl some structure

1 files changed, 157 insertions, 153 deletions

diff --git a/src/rabbit.erl b/src/rabbit.erl
index 2a7369c0..6ef816c0 100644
--- a/src/rabbit.erl
+++ b/src/rabbit.erl
@@ -23,7 +23,7 @@
 
 -export([start/2, stop/1]).
 
--export([log_location/1]).
+-export([log_location/1]). %% for testing
 
 %%---------------------------------------------------------------------------
 %% Boot steps.
@@ -267,20 +267,51 @@ stop(_State) ->
     ok.
 
 %%---------------------------------------------------------------------------
+%% application life cycle
 
-erts_version_check() ->
-    FoundVer = erlang:system_info(version),
-    case rabbit_misc:version_compare(?ERTS_MINIMUM, FoundVer, lte) of
-        true  -> ok;
-        false -> {error, {erlang_version_too_old,
-                          {found, FoundVer}, {required, ?ERTS_MINIMUM}}}
+application_load_order() ->
+    ok = load_applications(),
+    {ok, G} = rabbit_misc:build_acyclic_graph(
+                fun (App, _Deps) -> [{App, App}] end,
+                fun (App,  Deps) -> [{Dep, App} || Dep <- Deps] end,
+                [{App, app_dependencies(App)} ||
+                    {App, _Desc, _Vsn} <- application:loaded_applications()]),
+    true = digraph:del_vertices(
+             G, digraph:vertices(G) -- digraph_utils:reachable(?APPS, G)),
+    Result = digraph_utils:topsort(G),
+    true = digraph:delete(G),
+    Result.
+
+load_applications() ->
+    load_applications(queue:from_list(?APPS), sets:new()).
+
+load_applications(Worklist, Loaded) ->
+    case queue:out(Worklist) of
+        {empty, _WorkList} ->
+            ok;
+        {{value, App}, Worklist1} ->
+            case sets:is_element(App, Loaded) of
+                true  -> load_applications(Worklist1, Loaded);
+                false -> case application:load(App) of
+                             ok                             -> ok;
+                             {error, {already_loaded, App}} -> ok;
+                             Error                          -> throw(Error)
+                         end,
+                         load_applications(
+                           queue:join(Worklist1,
+                                      queue:from_list(app_dependencies(App))),
+                           sets:add_element(App, Loaded))
+            end
     end.
 
-boot_error(Format, Args) ->
-    io:format("BOOT ERROR: " ++ Format, Args),
-    error_logger:error_msg(Format, Args),
-    timer:sleep(1000),
-    exit({?MODULE, failure_during_boot}).
+app_dependencies(App) ->
+    case application:get_key(App, applications) of
+        undefined -> [];
+        {ok, Lst} -> Lst
+    end.
+
+%%---------------------------------------------------------------------------
+%% boot step logic
 
 run_boot_step({StepName, Attributes}) ->
     Description = case lists:keysearch(description, 1, Attributes) of
@@ -355,129 +386,46 @@ sort_boot_steps(UnsortedSteps) ->
                end])
     end.
 
-%%---------------------------------------------------------------------------
-
-log_location(Type) ->
-    case application:get_env(Type, case Type of
-                                       kernel -> error_logger;
-                                       sasl   -> sasl_error_logger
-                                   end) of
-        {ok, {file, File}} -> File;
-        {ok, false}        -> undefined;
-        {ok, tty}          -> tty;
-        {ok, silent}       -> undefined;
-        {ok, Bad}          -> throw({error, {cannot_log_to_file, Bad}});
-        _                  -> undefined
-    end.
-
-app_location() ->
-    {ok, Application} = application:get_application(),
-    filename:absname(code:where_is_file(atom_to_list(Application) ++ ".app")).
-
-home_dir() ->
-    case init:get_argument(home) of
-        {ok, [[Home]]} -> Home;
-        Other          -> Other
-    end.
-
-config_files() ->
-    case init:get_argument(config) of
-        {ok, Files} -> [filename:absname(
-                          filename:rootname(File, ".config") ++ ".config") ||
-                           File <- Files];
-        error       -> []
-    end.
+boot_error(Format, Args) ->
+    io:format("BOOT ERROR: " ++ Format, Args),
+    error_logger:error_msg(Format, Args),
+    timer:sleep(1000),
+    exit({?MODULE, failure_during_boot}).
 
 %%---------------------------------------------------------------------------
+%% boot step functions
 
-load_applications() ->
-    load_applications(queue:from_list(?APPS), sets:new()).
-
-load_applications(Worklist, Loaded) ->
-    case queue:out(Worklist) of
-        {empty, _WorkList} ->
-            ok;
-        {{value, App}, Worklist1} ->
-            case sets:is_element(App, Loaded) of
-                true  -> load_applications(Worklist1, Loaded);
-                false -> case application:load(App) of
-                             ok                             -> ok;
-                             {error, {already_loaded, App}} -> ok;
-                             Error                          -> throw(Error)
-                         end,
-                         load_applications(
-                           queue:join(Worklist1,
-                                      queue:from_list(app_dependencies(App))),
-                           sets:add_element(App, Loaded))
-            end
-    end.
+boot_delegate() ->
+    {ok, Count} = application:get_env(rabbit, delegate_count),
+    rabbit_sup:start_child(delegate_sup, [Count]).
 
-application_load_order() ->
-    ok = load_applications(),
-    {ok, G} = rabbit_misc:build_acyclic_graph(
-                fun application_graph_vertex/2, fun application_graph_edge/2,
-                [{App, app_dependencies(App)} ||
-                    {App, _Desc, _Vsn} <- application:loaded_applications()]),
-    true = digraph:del_vertices(
-             G, digraph:vertices(G) -- digraph_utils:reachable(?APPS, G)),
-    Result = digraph_utils:topsort(G),
-    true = digraph:delete(G),
-    Result.
+recover() ->
+    rabbit_binding:recover(rabbit_exchange:recover(), rabbit_amqqueue:start()).
 
-app_dependencies(App) ->
-    case application:get_key(App, applications) of
-        undefined -> [];
-        {ok, Lst} -> Lst
+maybe_insert_default_data() ->
+    case rabbit_mnesia:is_db_empty() of
+        true -> insert_default_data();
+        false -> ok
     end.
 
-application_graph_vertex(App, _Deps) -> [{App, App}].
-
-application_graph_edge(App, Deps) -> [{Dep, App} || Dep <- Deps].
+insert_default_data() ->
+    {ok, DefaultUser} = application:get_env(default_user),
+    {ok, DefaultPass} = application:get_env(default_pass),
+    {ok, DefaultTags} = application:get_env(default_user_tags),
+    {ok, DefaultVHost} = application:get_env(default_vhost),
+    {ok, [DefaultConfigurePerm, DefaultWritePerm, DefaultReadPerm]} =
+        application:get_env(default_permissions),
+    ok = rabbit_vhost:add(DefaultVHost),
+    ok = rabbit_auth_backend_internal:add_user(DefaultUser, DefaultPass),
+    ok = rabbit_auth_backend_internal:set_tags(DefaultUser, DefaultTags),
+    ok = rabbit_auth_backend_internal:set_permissions(DefaultUser, DefaultVHost,
+                                                      DefaultConfigurePerm,
+                                                      DefaultWritePerm,
+                                                      DefaultReadPerm),
+    ok.
 
 %%---------------------------------------------------------------------------
-
-print_banner() ->
-    {ok, Product} = application:get_key(id),
-    {ok, Version} = application:get_key(vsn),
-    ProductLen = string:len(Product),
-    io:format("~n"
-              "+---+   +---+~n"
-              "|   |   |   |~n"
-              "|   |   |   |~n"
-              "|   |   |   |~n"
-              "|   +---+   +-------+~n"
-              "|                   |~n"
-              "| ~s  +---+   |~n"
-              "|           |   |   |~n"
-              "| ~s  +---+   |~n"
-              "|                   |~n"
-              "+-------------------+~n"
-              "~s~n~s~n~s~n~n",
-              [Product, string:right([$v|Version], ProductLen),
-               ?PROTOCOL_VERSION,
-               ?COPYRIGHT_MESSAGE, ?INFORMATION_MESSAGE]),
-    Settings = [{"node",           node()},
-                {"app descriptor", app_location()},
-                {"home dir",       home_dir()},
-                {"config file(s)", config_files()},
-                {"cookie hash",    rabbit_misc:cookie_hash()},
-                {"log",            log_location(kernel)},
-                {"sasl log",       log_location(sasl)},
-                {"database dir",   rabbit_mnesia:dir()},
-                {"erlang version", erlang:system_info(version)}],
-    DescrLen = 1 + lists:max([length(K) || {K, _V} <- Settings]),
-    Format = fun (K, V) ->
-                     io:format("~-" ++ integer_to_list(DescrLen) ++ "s: ~s~n",
-                               [K, V])
-             end,
-    lists:foreach(fun ({"config file(s)" = K, []}) ->
-                          Format(K, "(none)");
-                      ({"config file(s)" = K, [V0 | Vs]}) ->
-                          Format(K, V0), [Format("", V) || V <- Vs];
-                      ({K, V}) ->
-                          Format(K, V)
-                  end, Settings),
-    io:nl().
+%% logging
 
 ensure_working_log_handlers() ->
     Handlers = gen_event:which_handlers(error_logger),
@@ -516,35 +464,19 @@ ensure_working_log_handler(OldFHandler, NewFHandler, TTYHandler,
                      end
     end.
 
-boot_delegate() ->
-    {ok, Count} = application:get_env(rabbit, delegate_count),
-    rabbit_sup:start_child(delegate_sup, [Count]).
-
-recover() ->
-    rabbit_binding:recover(rabbit_exchange:recover(), rabbit_amqqueue:start()).
-
-maybe_insert_default_data() ->
-    case rabbit_mnesia:is_db_empty() of
-        true -> insert_default_data();
-        false -> ok
+log_location(Type) ->
+    case application:get_env(Type, case Type of
+                                       kernel -> error_logger;
+                                       sasl   -> sasl_error_logger
+                                   end) of
+        {ok, {file, File}} -> File;
+        {ok, false}        -> undefined;
+        {ok, tty}          -> tty;
+        {ok, silent}       -> undefined;
+        {ok, Bad}          -> throw({error, {cannot_log_to_file, Bad}});
+        _                  -> undefined
     end.
 
-insert_default_data() ->
-    {ok, DefaultUser} = application:get_env(default_user),
-    {ok, DefaultPass} = application:get_env(default_pass),
-    {ok, DefaultTags} = application:get_env(default_user_tags),
-    {ok, DefaultVHost} = application:get_env(default_vhost),
-    {ok, [DefaultConfigurePerm, DefaultWritePerm, DefaultReadPerm]} =
-        application:get_env(default_permissions),
-    ok = rabbit_vhost:add(DefaultVHost),
-    ok = rabbit_auth_backend_internal:add_user(DefaultUser, DefaultPass),
-    ok = rabbit_auth_backend_internal:set_tags(DefaultUser, DefaultTags),
-    ok = rabbit_auth_backend_internal:set_permissions(DefaultUser, DefaultVHost,
-                                                      DefaultConfigurePerm,
-                                                      DefaultWritePerm,
-                                                      DefaultReadPerm),
-    ok.
-
 rotate_logs(File, Suffix, Handler) ->
     rotate_logs(File, Suffix, Handler, Handler).
 
@@ -567,3 +499,75 @@ log_rotation_result(ok, {error, SaslLogError}) ->
     {error, {cannot_rotate_sasl_logs, SaslLogError}};
 log_rotation_result(ok, ok) ->
     ok.
+
+%%---------------------------------------------------------------------------
+%% misc
+
+erts_version_check() ->
+    FoundVer = erlang:system_info(version),
+    case rabbit_misc:version_compare(?ERTS_MINIMUM, FoundVer, lte) of
+        true  -> ok;
+        false -> {error, {erlang_version_too_old,
+                          {found, FoundVer}, {required, ?ERTS_MINIMUM}}}
+    end.
+
+print_banner() ->
+    {ok, Product} = application:get_key(id),
+    {ok, Version} = application:get_key(vsn),
+    ProductLen = string:len(Product),
+    io:format("~n"
+              "+---+   +---+~n"
+              "|   |   |   |~n"
+              "|   |   |   |~n"
+              "|   |   |   |~n"
+              "|   +---+   +-------+~n"
+              "|                   |~n"
+              "| ~s  +---+   |~n"
+              "|           |   |   |~n"
+              "| ~s  +---+   |~n"
+              "|                   |~n"
+              "+-------------------+~n"
+              "~s~n~s~n~s~n~n",
+              [Product, string:right([$v|Version], ProductLen),
+               ?PROTOCOL_VERSION,
+               ?COPYRIGHT_MESSAGE, ?INFORMATION_MESSAGE]),
+    Settings = [{"node",           node()},
+                {"app descriptor", app_location()},
+                {"home dir",       home_dir()},
+                {"config file(s)", config_files()},
+                {"cookie hash",    rabbit_misc:cookie_hash()},
+                {"log",            log_location(kernel)},
+                {"sasl log",       log_location(sasl)},
+                {"database dir",   rabbit_mnesia:dir()},
+                {"erlang version", erlang:system_info(version)}],
+    DescrLen = 1 + lists:max([length(K) || {K, _V} <- Settings]),
+    Format = fun (K, V) ->
+                     io:format("~-" ++ integer_to_list(DescrLen) ++ "s: ~s~n",
+                               [K, V])
+             end,
+    lists:foreach(fun ({"config file(s)" = K, []}) ->
+                          Format(K, "(none)");
+                      ({"config file(s)" = K, [V0 | Vs]}) ->
+                          Format(K, V0), [Format("", V) || V <- Vs];
+                      ({K, V}) ->
+                          Format(K, V)
+                  end, Settings),
+    io:nl().
+
+app_location() ->
+    {ok, Application} = application:get_application(),
+    filename:absname(code:where_is_file(atom_to_list(Application) ++ ".app")).
+
+home_dir() ->
+    case init:get_argument(home) of
+        {ok, [[Home]]} -> Home;
+        Other          -> Other
+    end.
+
+config_files() ->
+    case init:get_argument(config) of
+        {ok, Files} -> [filename:absname(
+                          filename:rootname(File, ".config") ++ ".config") ||
+                           File <- Files];
+        error       -> []
+    end.