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
170
171
172
|
local id = require "util.id";
-- Library configuration (see configure())
local auto_inject_traceback = false;
local display_tracebacks = false;
local error_mt = { __name = "error" };
function error_mt:__tostring()
if display_tracebacks and self.context.traceback then
return ("error<%s:%s:%s:%s>"):format(self.type, self.condition, self.text or "", self.context.traceback);
end
return ("error<%s:%s:%s>"):format(self.type, self.condition, self.text or "");
end
local function is_error(e)
return getmetatable(e) == error_mt;
end
local function configure(opt)
if opt.display_tracebacks ~= nil then
display_tracebacks = opt.display_tracebacks;
end
if opt.auto_inject_traceback ~= nil then
auto_inject_traceback = opt.auto_inject_traceback;
end
end
-- Do we want any more well-known fields?
-- Or could we just copy all fields from `e`?
-- Sometimes you want variable details in the `text`, how to handle that?
-- Translations?
-- Should the `type` be restricted to the stanza error types or free-form?
-- What to set `type` to for stream errors or SASL errors? Those don't have a 'type' attr.
local function new(e, context, registry, source)
if is_error(e) then return e; end
local template = registry and registry[e];
if not template then
if type(e) == "table" then
template = {
code = e.code;
type = e.type;
condition = e.condition;
text = e.text;
extra = e.extra;
};
else
template = {};
end
end
context = context or {};
if auto_inject_traceback then
context.traceback = debug.traceback("error stack", 2);
end
local error_instance = setmetatable({
instance_id = id.short();
type = template.type or "cancel";
condition = template.condition or "undefined-condition";
text = template.text;
code = template.code;
extra = template.extra;
context = context;
source = source;
}, error_mt);
return error_instance;
end
-- compact --> normal form
local function expand_registry(namespace, registry)
local mapped = {}
for err,template in pairs(registry) do
local e = {
type = template[1];
condition = template[2];
text = template[3];
};
if namespace and template[4] then
e.extra = { namespace = namespace, condition = template[4] };
end
mapped[err] = e;
end
return mapped;
end
local function init(source, namespace, registry)
if type(namespace) == "table" then
-- registry can be given as second argument if namespace is not used
registry, namespace = namespace, nil;
end
local _, protoerr = next(registry, nil);
if protoerr and type(next(protoerr)) == "number" then
registry = expand_registry(namespace, registry);
end
local function wrap(e, context)
if is_error(e) then
return e;
end
local err = new(registry[e] or {
type = "cancel", condition = "undefined-condition"
}, context, registry, source);
err.context.wrapped_error = e;
return err;
end
return {
source = source;
registry = registry;
new = function (e, context)
return new(e, context, registry, source);
end;
coerce = function (ok, err, ...)
if ok then
return ok, err, ...;
end
return nil, wrap(err);
end;
wrap = wrap;
};
end
local function coerce(ok, err, ...)
if ok or is_error(err) then
return ok, err, ...;
end
local new_err = new({
type = "cancel", condition = "undefined-condition"
}, { wrapped_error = err });
return ok, new_err, ...;
end
local function from_stanza(stanza, context, source)
local error_type, condition, text, extra_tag = stanza:get_error();
local error_tag = stanza:get_child("error");
context = context or {};
context.stanza = stanza;
context.by = error_tag.attr.by or stanza.attr.from;
local uri;
if condition == "gone" or condition == "redirect" then
uri = error_tag:get_child_text(condition, "urn:ietf:params:xml:ns:xmpp-stanzas");
end
return new({
type = error_type or "cancel";
condition = condition or "undefined-condition";
text = text;
extra = (extra_tag or uri) and {
uri = uri;
tag = extra_tag;
} or nil;
}, context, nil, source);
end
return {
new = new;
init = init;
coerce = coerce;
is_error = is_error;
is_err = is_error; -- COMPAT w/ older 0.12 trunk
from_stanza = from_stanza;
configure = configure;
}
|