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# Log Reader Binding
This binding reads and analyzes log files. Search patterns are fully configurable, therefore different kind of log files should be possible to monitor by this binding. When certain log events are recognized, openHAB rules can be used to send notification about the event e.g by email for further analysis.
# Supported Things
This binding supports one ThingType: reader
.
A reader supports 3 separate channels
- One for errors
- one for warnings
- one custom channel for other purposes.
# Thing Configuration
The reader
Thing has the following configuration parameters:
Parameter | Type | Required | Default if omitted | Description |
---|---|---|---|---|
filePath | String | yes | ${OPENHAB_LOGDIR}/openhab.log | Path to log file. ${OPENHAB_LOGDIR} is automatically replaced by the correct directory. |
refreshRate | integer | no | 1000 | Time in milliseconds between individual log reads. |
errorPatterns | String | no | ERROR+ | Search patterns separated by | character for error events. |
errorBlacklistingPatterns | String | no | Search patterns for blacklisting unwanted error events separated by | character. | |
warningPatterns | String | no | WARN+ | Search patterns separated by | character for warning events. |
warningBlacklistingPatterns | String | no | Search patterns for blacklisting unwanted warning events separated by | character. | |
customPatterns | String | no | Search patterns separated by | character for custom events. | |
customBlacklistingPatterns | String | no | Search patterns for blacklisting unwanted custom events separated by | character. |
Search patterns follows Java regular expression syntax (opens new window). Be aware that search patterns are case sensitive.
# Channels
List of channels
Channel Type ID | Item Type | Description |
---|---|---|
lastErrorEvent | String | Displays content of last [ERROR] event |
lastWarningEvent | String | Displays content of last [WARN] event |
lastCustomEvent | String | Displays content of last [CUSTOM] event |
errorEvents | Number | Displays number of [ERROR] lines matched to search pattern |
warningEvents | Number | Displays number of [WARN] lines matched to search pattern |
customEvents | Number | Displays number of [CUSTOM] lines matched to search pattern |
logRotated | DateTime | Last time when log rotated recognized |
newErrorEvent | - | Trigger channel for last [ERROR] line |
newWarningEvent | - | Trigger channel for last [WARN] line |
newCustomEvent | - | Trigger channel for last [CUSTOM] line |
# Examples
# example.things
logreader:reader:openhablog[ refreshRate=1000, errorPatterns="ERROR+", errorBlacklistingPatterns="annoying error which should be ignored|Another annoying error which should be ignored" ]
# example.items
DateTime logreaderLogRotated "Last Log Rotation [%1$tY.%1$tm.%1$te %1$tR]" <time> { channel="logreader:reader:openhablog:logRotated" }
Number logreaderErrors "Error events matched [%d]" <alarm> { channel="logreader:reader:openhablog:errorEvents" }
String logreaderLastError "Last error [%s]" { channel="logreader:reader:openhablog:lastErrorEvent" }
Number logreaderWarnings "Warning events matched [%d]" <alarm> { channel="logreader:reader:openhablog:warningEvents" }
String logreaderLastWarning "Last warning [%s]" { channel="logreader:reader:openhablog:lastWarningEvent" }
Number logreaderCustoms "Custom events matched [%d]" <alarm> { channel="logreader:reader:openhablog:customEvents" }
String logreaderLastCustom "Last Custom [%s]" { channel="logreader:reader:openhablog:lastCustomEvent" }
# example.sitemap
sitemap logreader_example label="Example" {
Frame label="openHAB Log Reader" {
Text item=logreaderErrors
Text item=logreaderLastError
Text item=logreaderWarnings
Text item=logreaderLastWarning
Text item=logreaderCustoms
Text item=logreaderLastCustom
Text item=logreaderLogRotated
}
}
# example.rules
rule "LogReader"
when
Channel "logreader:reader:openhablog:newErrorEvent" triggered
then
// do something
end
Use the rules with your Telegram Bot (need openHAB Telegram Binding installed and configured)
rule "LogReader"
when
Channel 'logreader:reader:openhablog:newErrorEvent' triggered
then
val telegramAction = getActions("telegram","telegram:telegramBot:myBot")
telegramAction.sendTelegram("*ERROR* LogReader Event!\n%s Errors are in the log! Here is the last row of it:\n`%s`", logreaderErrors.state.toString, logreaderLastError.state.toString)
end
Be careful when sending e.g. email notifications. You could easily send thousand of spam emails in short period if e.g. one binding is in error loop.
# Thing status
Check thing status for errors.
# Verbose logging
Enable DEBUG logging in karaf console to see more precise error messages:
log:set DEBUG org.openhab.binding.logreader
See openHAB2 logging docs (opens new window) for more help.