1logger_filters(3) Erlang Module Definition logger_filters(3)
2
6 logger_filters - Filters to use with Logger.
7
9 All functions exported from this module can be used as primary or han‐
10 dler filters. See logger:add_primary_filter/2 and logger:add_han‐
11 dler_filter/3 for more information about how filters are added.
12 Filters are removed with logger:remove_primary_filter/1 and log‐
14 ger:remove_handler_filter/2.
15
17 domain(LogEvent, Extra) -> logger:filter_return()
18 Types:
20 LogEvent = logger:log_event()
22 Extra = {Action, Compare, MatchDomain}
23 Action = log | stop
24 Compare = super | sub | equal | not_equal | undefined
25 MatchDomain = [atom()]
26 This filter provides a way of filtering log events based on a
28 domain field in Metadata. This field is optional, and the pur‐
29 pose of using it is to group log events from, for example, a
30 specific functional area. This allows filtering or other spe‐
31 cialized treatment in a Logger handler.
32 A domain field must be a list of atoms, creating smaller and
34 more specialized domains as the list grows longer. The greatest
35 domain is [], which comprises all possible domains.
36 For example, consider the following domains:
38 D1 = [otp]
40 D2 = [otp, sasl]
41 D1 is the greatest of the two, and is said to be a super-domain
43 of D2. D2 is a sub-domain D1. Both D1 and D2 are sub-domains of
44 [].
45 The above domains are used for logs originating from Erlang/OTP.
47 D1 specifies that the log event comes from Erlang/OTP in gen‐
48 eral, and D2 indicates that the log event is a so called SASL
49 report.
50 The Extra parameter to the domain/2 function is specified when
52 adding the filter via logger:add_primary_filter/2 or log‐
53 ger:add_handler_filter/3.
54 The filter compares the value of the domain field in the log
56 event's metadata (Domain) against MatchDomain. The filter
57 matches if the value of Compare is:
58 sub:
60 and Domain is equal to or a sub-domain of MatchDomain, that
61 is, if MatchDomain is a prefix of Domain.
62 super:
64 and Domain is equal to or a super-domain of MatchDomain,
65 that is, if Domain is a prefix of MatchDomain.
66 equal:
68 and Domain is equal to MatchDomain.
69 not_equal:
71 and Domain differs from MatchDomain, or if there is no
72 domain field in metadata.
73 undefined:
75 and there is no domain field in metadata. In this case
76 MatchDomain must be set to [].
77 If the filter matches and Action is log, the log event is
79 allowed. If the filter matches and Action is stop, the log event
80 is stopped.
81 If the filter does not match, it returns ignore, meaning that
83 other filters, or the value of the configuration parameter fil‐
84 ter_default, decide if the event is allowed or not.
85 Log events that do not contain any domain field, match only when
87 Compare is equal to undefined or not_equal.
88 Example: stop all events with domain [otp, sasl | _]
90 logger:set_handler_config(h1, filter_default, log). % this is the default
92 Filter = {fun logger_filters:domain/2, {stop, sub, [otp, sasl]}}.
93 logger:add_handler_filter(h1, no_sasl, Filter).
94 ok
95 level(LogEvent, Extra) -> logger:filter_return()
97 Types:
99 LogEvent = logger:log_event()
101 Extra = {Action, Operator, MatchLevel}
102 Action = log | stop
103 Operator = neq | eq | lt | gt | lteq | gteq
104 MatchLevel = logger:level()
105 This filter provides a way of filtering log events based on the
107 log level. It matches log events by comparing the log level with
108 a specified MatchLevel
109 The Extra parameter is specified when adding the filter via log‐
111 ger:add_primary_filter/2 or logger:add_handler_filter/3.
112 The filter compares the value of the event's log level (Level)
114 to MatchLevel by calling logger:compare_levels(Level, Match‐
115 Level). The filter matches if the value of Operator is:
116 neq:
118 and the compare function returns lt or gt.
119 eq:
121 and the compare function returns eq.
122 lt:
124 and the compare function returns lt.
125 gt:
127 and the compare function returns gt.
128 lteq:
130 and the compare function returns lt or eq.
131 gteq:
133 and the compare function returns gt or eq.
134 If the filter matches and Action is log, the log event is
136 allowed. If the filter matches and Action is stop, the log event
137 is stopped.
138 If the filter does not match, it returns ignore, meaning that
140 other filters, or the value of the configuration parameter fil‐
141 ter_default, will decide if the event is allowed or not.
142 Example: only allow debug level log events
144 logger:set_handler_config(h1, filter_default, stop).
146 Filter = {fun logger_filters:level/2, {log, eq, debug}}.
147 logger:add_handler_filter(h1, debug_only, Filter).
148 ok
149 progress(LogEvent, Extra) -> logger:filter_return()
151 Types:
153 LogEvent = logger:log_event()
155 Extra = log | stop
156 This filter matches all progress reports from supervisor and
158 application_controller.
159 If Extra is log, the progress reports are allowed. If Extra is
161 stop, the progress reports are stopped.
162 The filter returns ignore for all other log events.
164 remote_gl(LogEvent, Extra) -> logger:filter_return()
166 Types:
168 LogEvent = logger:log_event()
170 Extra = log | stop
171 This filter matches all events originating from a process that
173 has its group leader on a remote node.
174 If Extra is log, the matching events are allowed. If Extra is
176 stop, the matching events are stopped.
177 The filter returns ignore for all other log events.
179
181 logger(3)
182Ericsson AB kernel 7.3 logger_filters(3)