Chapter 63. Log
Log Component
The log: component logs message exchanges to the underlying logging mechanism.
URI format
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.
Also a log in the DSL
In Camel 2.2 onwards there is a
log directly in the DSL, but it has a different purpose. Its meant for lightweight and human logs. See more details at section "LogEIP" in "Implementing Enterprise Integration Patterns".
Options
| 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
|
Camel 2.6: If specified will group message stats by this time interval (in millis) |
groupDelay
|
0
|
Integer
|
Camel 2.6: Set the initial delay for stats (in millis) |
groupActiveOnly
|
true
|
boolean
|
Camel 2.6: If true, will hide stats when no new messages have been received for a time interval, if false, show stats regardless of message traffic |
Formatting
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
|
Camel 2.3: 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
|
Camel 2.1: 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 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.
|
Logging stream bodies
For older versions of Camel that do not support the showFiles or showStreams properties above, 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);
Regular logger sample
In the route below we log the incoming orders at
DEBUG level before the order is processed:
from("activemq:orders").to("log:com.mycompany.order?level=DEBUG").to("bean:processOrder");
Or using Spring XML to define the route:
<route>
<from uri="activemq:orders"/>
<to uri="log:com.mycompany.order?level=DEBUG"/>
<to uri="bean:processOrder"/>
</route>Regular logger with formatter sample
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");Throughput logger with groupSize sample
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");Throughput logger with groupInterval sample
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"
