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Diffstat (limited to 'src/rabbit_mnesia_rename.erl')
| -rw-r--r-- | src/rabbit_mnesia_rename.erl | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/src/rabbit_mnesia_rename.erl b/src/rabbit_mnesia_rename.erl new file mode 100644 index 00000000..ef3854de --- /dev/null +++ b/src/rabbit_mnesia_rename.erl @@ -0,0 +1,160 @@ +%% The contents of this file are subject to the Mozilla Public License +%% Version 1.1 (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.mozilla.org/MPL/ +%% +%% Software distributed under the License is distributed on an "AS IS" +%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See +%% the License for the specific language governing rights and +%% limitations under the License. +%% +%% The Original Code is RabbitMQ. +%% +%% The Initial Developer of the Original Code is GoPivotal, Inc. +%% Copyright (c) 2007-2014 GoPivotal, Inc. All rights reserved. +%% + +-module(rabbit_mnesia_rename). +-include("rabbit.hrl"). + +-export([rename/3]). +-export([maybe_complete_rename/1]). + +-define(CONVERT_TABLES, [schema, rabbit_durable_queue]). + +%%---------------------------------------------------------------------------- + +-ifdef(use_specs). + +-spec(rename/3 :: (node(), node(), [node()]) -> 'ok'). +-spec(maybe_complete_rename/1 :: ([node()]) -> 'ok'). + +-endif. + +%%---------------------------------------------------------------------------- + +rename(FromNode, ToNode, Others) -> + NodeMap = dict:from_list(split_others([FromNode, ToNode | Others])), + try + rabbit_control_main:become(FromNode), + rabbit_log:info("Renaming node ~s to ~s~n", [FromNode, ToNode]), + start_mnesia(), + Nodes = rabbit_mnesia:cluster_nodes(all), + case {lists:member(FromNode, Nodes), lists:member(ToNode, Nodes)} of + {true, false} -> ok; + {false, _} -> exit({node_not_in_cluster, FromNode}); + {_, true} -> exit({node_already_in_cluster, ToNode}) + end, + rabbit_table:force_load(), + rabbit_table:wait_for_replicated(), + FromBackup = from_backup_name(), + ToBackup = to_backup_name(), + io:format(" * Backing up to '~s'~n", [FromBackup]), + ok = mnesia:backup(FromBackup), + stop_mnesia(), + io:format(" * Converting backup '~s'~n", [ToBackup]), + convert_backup(NodeMap, FromBackup, ToBackup), + ok = rabbit_file:write_term_file(rename_config_name(), + [{FromNode, ToNode}]), + io:format(" * Converting config files~n", []), + convert_config_file(NodeMap, + rabbit_node_monitor:running_nodes_filename()), + convert_config_file(NodeMap, + rabbit_node_monitor:cluster_status_filename()), + ok + after + stop_mnesia() + end. + +split_others([]) -> []; +split_others([_]) -> exit(even_list_needed); +split_others([A, B | T]) -> [{A, B} | split_others(T)]. + +maybe_complete_rename(AllNodes) -> + case rabbit_file:read_term_file(rename_config_name()) of + {ok, [{FromNode, ToNode}]} -> + case rabbit_upgrade:nodes_running(AllNodes) of + [] -> complete_rename_primary(); + _ -> complete_rename_secondary(FromNode, ToNode, AllNodes) + end; + _ -> + ok + end. + +complete_rename_primary() -> + %% We are alone, restore the backup we previously took + ToBackup = to_backup_name(), + io:format(" * Loading backup '~s'~n", [ToBackup]), + ok = mnesia:install_fallback(ToBackup, [{scope, local}]), + start_mnesia(), + stop_mnesia(), + rabbit_file:delete(rename_config_name()), + rabbit_file:delete(from_backup_name()), + rabbit_file:delete(to_backup_name()), + rabbit_mnesia:force_load_next_boot(), + ok. + +complete_rename_secondary(FromNode, ToNode, AllNodes) -> + rabbit_upgrade:secondary_upgrade(AllNodes), + rename_remote_node(FromNode, ToNode), + rabbit_file:delete(rename_config_name()), + rabbit_file:delete(from_backup_name()), + rabbit_file:delete(to_backup_name()), + ok. + +from_backup_name() -> rabbit_mnesia:dir() ++ "/rename-backup-from". +to_backup_name() -> rabbit_mnesia:dir() ++ "/rename-backup-to". +rename_config_name() -> rabbit_mnesia:dir() ++ "/rename-pending.config". + +start_mnesia() -> rabbit_misc:ensure_ok(mnesia:start(), cannot_start_mnesia). +stop_mnesia() -> stopped = mnesia:stop(). + +convert_backup(NodeMap, FromBackup, ToBackup) -> + mnesia:traverse_backup( + FromBackup, ToBackup, + fun + (Row, Acc) -> + case lists:member(element(1, Row), ?CONVERT_TABLES) of + true -> {[update_term(NodeMap, Row)], Acc}; + false -> {[Row], Acc} + end + end, switched). + +convert_config_file(NodeMap, Path) -> + {ok, Term} = rabbit_file:read_term_file(Path), + ok = rabbit_file:write_term_file(Path, update_term(NodeMap, Term)). + +lookup_node(OldNode, NodeMap) -> + case dict:find(OldNode, NodeMap) of + {ok, NewNode} -> NewNode; + error -> OldNode + end. + +update_term(NodeMap, L) when is_list(L) -> + [update_term(NodeMap, I) || I <- L]; +update_term(NodeMap, T) when is_tuple(T) -> + list_to_tuple(update_term(NodeMap, tuple_to_list(T))); +update_term(NodeMap, Node) when is_atom(Node) -> + lookup_node(Node, NodeMap); +update_term(NodeMap, Pid) when is_pid(Pid) -> + rabbit_misc:pid_change_node(Pid, lookup_node(node(Pid), NodeMap)); +update_term(_NodeMap, Term) -> + Term. + +%%---------------------------------------------------------------------------- + +rename_remote_node(FromNode, ToNode) -> + All = rabbit_mnesia:cluster_nodes(all), + Running = rabbit_mnesia:cluster_nodes(running), + case {lists:member(FromNode, Running), lists:member(ToNode, All)} of + {false, true} -> ok; + {true, _} -> exit({old_node_running, FromNode}); + {_, false} -> exit({new_node_not_in_cluster, ToNode}) + end, + mnesia:del_table_copy(schema, FromNode), + NodeMap = dict:from_list([{FromNode, ToNode}]), + {atomic, ok} = mnesia:transform_table( + rabbit_durable_queue, + fun (Q) -> update_term(NodeMap, Q) end, + record_info(fields, amqqueue)), + ok. |