1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
|
%%%----------------------------------------------------------------------
%%% File : mnesia_mnesia.erl
%%% Author : Christophe Romain <christophe.romain@process-one.net>
%%% Purpose : Handle configurable mnesia schema
%%% Created : 17 Nov 2016 by Christophe Romain <christophe.romain@process-one.net>
%%%
%%%
%%% ejabberd, Copyright (C) 2002-2017 ProcessOne
%%%
%%% This program is free software; you can redistribute it and/or
%%% modify it under the terms of the GNU General Public License as
%%% published by the Free Software Foundation; either version 2 of the
%%% License, or (at your option) any later version.
%%%
%%% This program is distributed in the hope that it will be useful,
%%% but WITHOUT ANY WARRANTY; without even the implied warranty of
%%% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
%%% General Public License for more details.
%%%
%%% You should have received a copy of the GNU General Public License along
%%% with this program; if not, write to the Free Software Foundation, Inc.,
%%% 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
%%%
%%%----------------------------------------------------------------------
%%% This module should be used everywhere ejabberd creates a mnesia table
%%% to make the schema customizable without code change
%%% Just apply this change in ejabberd modules
%%% s/ejabberd_mnesia:create(?MODULE, /ejabberd_mnesia:create(?MODULE, /
-module(ejabberd_mnesia).
-author('christophe.romain@process-one.net').
-export([create/3, reset/2, update/2]).
-define(STORAGE_TYPES, [disc_copies, disc_only_copies, ram_copies]).
-define(NEED_RESET, [local_content, type]).
create(Module, Name, TabDef) ->
Schema = schema(Module, Name, TabDef),
{attributes, Attrs} = lists:keyfind(attributes, 1, Schema),
case catch mnesia:table_info(Name, attributes) of
{'EXIT', _} ->
mnesia:create_table(Name, Schema);
Attrs ->
case need_reset(TabDef, Schema) of
true -> reset(Name, Schema);
false -> update(Name, Schema)
end;
OldAttrs ->
Fun = case lists:member({transform,1}, Module:module_info(exports)) of
true -> fun(Old) -> Module:transform(Old) end;
false -> fun(Old) -> transform(OldAttrs, Attrs, Old) end
end,
mnesia:transform_table(Name, Fun, Attrs)
end.
reset(Name, TabDef) ->
mnesia:delete_table(Name),
ejabberd_mnesia:create(?MODULE, Name, TabDef).
update(Name, TabDef) ->
Storage = mnesia:table_info(Name, storage_type),
NewStorage = lists:foldl(
fun({Key, _}, Acc) ->
case lists:member(Key, ?STORAGE_TYPES) of
true -> Key;
false -> Acc
end
end, Storage, TabDef),
R1 = if Storage=/=NewStorage ->
mnesia:change_table_copy_type(Name, node(), NewStorage);
true ->
{atomic, ok}
end,
Indexes = mnesia:table_info(Name, index),
NewIndexes = proplists:get_value(index, TabDef, []),
[mnesia:del_table_index(Name, Attr)
|| Attr <- Indexes--NewIndexes],
R2 = [mnesia:add_table_index(Name, Attr)
|| Attr <- NewIndexes--Indexes],
lists:foldl(
fun({atomic, ok}, Acc) -> Acc;
(Error, _Acc) -> Error
end, {atomic, ok}, [R1|R2]).
%
% utilities
%
schema(Module, Name, TabDef) ->
case parse(Module) of
{ok, CustomDefs} ->
case lists:keyfind(Name, 1, CustomDefs) of
{Name, CustomDef} -> merge(TabDef, CustomDef);
_ -> TabDef
end;
_ ->
TabDef
end.
merge(TabDef, CustomDef) ->
{CustomKeys, _} = lists:unzip(CustomDef),
CleanDef = lists:foldl(
fun(Elem, Acc) ->
case lists:member(Elem, ?STORAGE_TYPES) of
true ->
lists:foldl(
fun(Key, CleanAcc) ->
lists:keydelete(Key, 1, CleanAcc)
end, Acc, ?STORAGE_TYPES);
false ->
Acc
end
end, TabDef, CustomKeys),
lists:ukeymerge(1,
lists:ukeysort(1, CustomDef),
lists:ukeysort(1, CleanDef)).
parse(Module) ->
Path = case os:getenv("EJABBERD_SCHEMA_PATH") of
false ->
case code:priv_dir(ejabberd) of
{error, _} -> "schema"; % $SPOOL_DIR/schema
Priv -> filename:join(Priv, "schema")
end;
CustomDir ->
CustomDir
end,
File = filename:join(Path, atom_to_list(Module)++".mnesia"),
case file:consult(File) of
{ok, Terms} -> parse(Terms, []);
Error -> Error
end.
parse([], Acc) ->
{ok, lists:reverse(Acc)};
parse([{Name, Storage, TabDef}|Tail], Acc)
when is_atom(Name),
is_atom(Storage),
is_list(TabDef) ->
NewDef = case lists:member(Storage, ?STORAGE_TYPES) of
true -> [{Storage, [node()]} | TabDef];
false -> TabDef
end,
parse(Tail, [{Name, NewDef} | Acc]);
parse([Other|_], _) ->
{error, {invalid, Other}}.
need_reset(FromDef, ToDef) ->
ValuesF = [lists:keyfind(Key, 1, FromDef) || Key <- ?NEED_RESET],
ValuesT = [lists:keyfind(Key, 1, ToDef) || Key <- ?NEED_RESET],
lists:foldl(
fun({Val, Val}, Acc) -> Acc;
({_, false}, Acc) -> Acc;
({_, _}, _) -> true
end, false, lists:zip(ValuesF, ValuesT)).
transform(OldAttrs, Attrs, Old) ->
[Name|OldValues] = tuple_to_list(Old),
Before = lists:zip(OldAttrs, OldValues),
After = lists:foldl(
fun(Attr, Acc) ->
case lists:keyfind(Attr, 1, Before) of
false -> [{Attr, undefined}|Acc];
Value -> [Value|Acc]
end
end, [], lists:reverse(Attrs)),
{Attrs, NewRecord} = lists:unzip(After),
list_to_tuple([Name|NewRecord]).
|
