log:loggingCategory[?options]
Where loggingCategory is the name of the logging
category to use. You can append query options to the URI in the following format,
?option=value&option=value&...
For example, a log endpoint typically specifies the logging level using the
level
option, as follows:
log:org.apache.camel.example?level=DEBUG
The default logger logs every exchange (regular logging). But
Apache Camel also ships with the Throughput
logger, which is used
whenever the groupSize
option is specified.
![]() | Note |
---|---|
In Apache Camel 2.2 onwards there is a
|
Option | Default | Type | Description |
---|---|---|---|
level
|
INFO
|
String
|
Logging level to use. Possible values: ERROR ,
WARN , INFO , DEBUG ,
TRACE , OFF
|
marker
|
null
|
String
|
Camel 2.9: An optional Marker name to use. |
groupSize
|
null
|
Integer
|
An integer that specifies a group size for throughput logging. |
groupInterval
|
null
|
Integer
|
If specified will group message stats by this time interval (in millis) |
groupDelay
|
0
|
Integer
|
Set the initial delay for stats (in millis) |
groupActiveOnly
|
true
|
boolean
|
If true, will hide stats when no new messages have been received for a time interval, if false, show stats regardless of message traffic |
The log formats the execution of exchanges to log lines. By default, the log uses
LogFormatter
to format the log output, where
LogFormatter
has the following options:
Option | Default | Description |
---|---|---|
showAll
|
false
|
Quick option for turning all options on (multiline, maxChars has to be manually set if to be used). |
showExchangeId
|
false
|
Show the unique exchange ID. |
showExchangePattern
|
true
|
Shows the Message Exchange Pattern (or MEP for short). |
showProperties
|
false
|
Show the exchange properties. |
showHeaders
|
false
|
Show the In message headers. |
showBodyType
|
true
|
Show the In body Java type. |
showBody
|
true
|
Show the In body. |
showOut
|
false
|
If the exchange has an Out message, show the Out message. |
showException
|
false
|
Apache Camel 2.0: If the exchange has an exception, show the exception message (no stack trace). |
showCaughtException
|
false
|
Apache Camel 2.0: If the exchange has a caught
exception, show the exception message (no stack trace). A caught exception is
stored as a property on the exchange and for instance a
doCatch can catch exceptions. See Try Catch Finally. |
showStackTrace
|
false
|
Apache Camel 2.0: Show the stack trace, if an
exchange has an exception. Only effective if one of showAll ,
showException or showCaughtException
are enabled. |
showFiles
|
false
|
Camel 2.9: Whether Camel should show file bodies or not (eg such as java.io.File). |
showFuture
|
false
|
Whether Camel should show java.util.concurrent.Future bodies
or not. If enabled Camel could potentially wait until the
Future task is done. Will by default not wait. |
showStreams
|
false
|
Camel 2.8: Whether Camel should show stream bodies or not (eg such as java.io.InputStream). Beware if you enable this option then you may not be able later to access the message body as the stream have already been read by this logger. To remedy this you will have to use Stream Caching. |
multiline
|
false
|
If true , each piece of information is logged on a new line.
|
maxChars
|
Limits the number of characters logged per line. The default value is
10000 from Camel 2.9
onwards. |
![]() | Note |
---|---|
For older versions of Camel that do not support the showFiles or showStreams properties, you can set the following property instead on the CamelContext to log both stream and file bodies: camelContext.getProperties().put(Exchange.LOG_DEBUG_BODY_STREAMS, true); |
In the route below we log the incoming orders at DEBUG
level before
the order is processed:
<route> <from uri="activemq:orders"/> <to uri="log:com.mycompany.order?level=DEBUG"/> <to uri="bean:processOrder"/> </route>
In the route below we log the incoming orders at INFO
level before
the order is processed.
from("activemq:orders"). to("log:com.mycompany.order?showAll=true&multiline=true").to("bean:processOrder");
In the route below we log the throughput of the incoming orders at
DEBUG
level grouped by 10 messages.
from("activemq:orders"). to("log:com.mycompany.order?level=DEBUG&groupSize=10").to("bean:processOrder");
This route will result in message stats logged every 10s, with an initial 60s delay and stats should be displayed even if there isn't any message traffic.
from("activemq:orders") .to("log:com.mycompany.order?level=DEBUG&groupInterval=10000&groupDelay=60000&groupActiveOnly=false") .to("bean:processOrder");
The following will be logged:
"Received: 1000 new messages, with total 2000 so far. Last group took: 10000 millis which is: 100 messages per second. average: 100"
Available as of Camel 2.11
With the options outlined in the Formatting section, you can control much of the output of the logger. However, log lines will always follow this structure:
Exchange[Id:ID-machine-local-50656-1234567901234-1-2, ExchangePattern:InOut, Properties:{CamelToEndpoint=log://org.apache.camel.component.log.TEST?showAll=true, CamelCreatedTimestamp=Thu Mar 28 00:00:00 WET 2013}, Headers:{breadcrumbId=ID-machine-local-50656-1234567901234-1-1}, BodyType:String, Body:Hello World, Out: null]
This format is unsuitable in some cases, perhaps because, among other things, you need to:
Filter the headers and properties that are printed, to strike a balance between insight and verbosity.
Adjust the log message to whatever you deem most readable.
Tailor log messages for digestion by log mining systems, e.g. Splunk.
Print specific body types differently.
Whenever you require absolute customization, you can create a class that implements
the ExchangeFormatter
interface. Within the format(Exchange)
method you have access
to the full Exchange, so you can select and extract the precise information you need,
format it in a custom manner and return it. The return value will become the final log
message.
You can have the Log component pick up your custom
ExchangeFormatter
in either of two ways:
Explicitly instantiating the LogComponent in your Registry:
<bean name="log" class="org.apache.camel.component.log.LogComponent"> <property name="exchangeFormatter" ref="myCustomFormatter" /> </bean>
Convention over configuration:
Simply by registering a bean with the name logFormatter
; the Log
Component is intelligent enough to pick it up automatically.
<bean name="logFormatter" class="com.xyz.MyCustomExchangeFormatter" />
NOTE: the ExchangeFormatter
gets applied to all Log endpoints within that Camel Context. If you need different
ExchangeFormatters for different endpoints, just instantiate the LogComponent as many
times as needed, and use the relevant bean name as the endpoint prefix.
From Camel 2.11.2/2.12 onwards when using a custom log formatter, you can specify parameters in the log uri, which gets configured on the custom log formatter. Though when you do that you should define the "logForamtter" as prototype scoped so its not shared if you have different parameters, eg:
<bean name="logFormatter" class="com.xyz.MyCustomExchangeFormatter" scope="prototype"/>
And then we can have Camel routes using the log uri with different options:
<to uri="log:foo?param1=foo&aram2=100"/> ... <to uri="log:bar?param1=bar&aram2=200"/>