Log
Since Camel 1.1
The log: component logs message exchanges to the underlying logging mechanism.
Camel uses sfl4j which allows you to configure logging via, among others:
-
Log4j
-
Logback
-
Java Util Logging
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&…
INFO:*Using Logger instance from the Registry*
As of Camel 2.12.4/2.13.1, if there’s single instance
of org.slf4j.Logger
found in the Registry, the loggingCategory is no
longer used to create logger instance. The registered instance is used
instead. Also it is possible to reference particular Logger
instance
using ?logger=#myLogger
URI parameter. Eventually, if there’s no
registered and URI logger
parameter, the logger instance is created
using loggingCategory.
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 Camel
also ships with the Throughput
logger, which is used whenever the
groupSize
option is specified.
TIP:*Also a log in the DSL*
There is also a log
directly in the DSL, but it has a different
purpose. Its meant for lightweight and human logs. See more details at
LogEIP.
Options
The Log component supports 2 options, which are listed below.
Name | Description | Default | Type |
---|---|---|---|
exchangeFormatter (advanced) |
Sets a custom ExchangeFormatter to convert the Exchange to a String suitable for logging. If not specified, we default to DefaultExchangeFormatter. |
ExchangeFormatter |
|
resolveProperty Placeholders (advanced) |
Whether the component should resolve property placeholders on itself when starting. Only properties which are of String type can use property placeholders. |
true |
boolean |
The Log endpoint is configured using URI syntax:
log:loggerName
with the following path and query parameters:
Path Parameters (1 parameters):
Name | Description | Default | Type |
---|---|---|---|
loggerName |
Required The logger name to use |
String |
Query Parameters (26 parameters):
Name | Description | Default | Type |
---|---|---|---|
groupActiveOnly (producer) |
If true, will hide stats when no new messages have been received for a time interval, if false, show stats regardless of message traffic. |
true |
Boolean |
groupDelay (producer) |
Set the initial delay for stats (in millis) |
Long |
|
groupInterval (producer) |
If specified will group message stats by this time interval (in millis) |
Long |
|
groupSize (producer) |
An integer that specifies a group size for throughput logging. |
Integer |
|
level (producer) |
Logging level to use. The default value is INFO. |
INFO |
String |
logMask (producer) |
If true, mask sensitive information like password or passphrase in the log. |
Boolean |
|
marker (producer) |
An optional Marker name to use. |
String |
|
synchronous (advanced) |
Sets whether synchronous processing should be strictly used, or Camel is allowed to use asynchronous processing (if supported). |
false |
boolean |
maxChars (formatting) |
Limits the number of characters logged per line. |
10000 |
int |
multiline (formatting) |
If enabled then each information is outputted on a newline. |
false |
boolean |
showAll (formatting) |
Quick option for turning all options on. (multiline, maxChars has to be manually set if to be used) |
false |
boolean |
showBody (formatting) |
Show the message body. |
true |
boolean |
showBodyType (formatting) |
Show the body Java type. |
true |
boolean |
showCaughtException (formatting) |
f the exchange has a caught exception, show the exception message (no stack trace). A caught exception is stored as a property on the exchange (using the key org.apache.camel.Exchange#EXCEPTION_CAUGHT and for instance a doCatch can catch exceptions. |
false |
boolean |
showException (formatting) |
If the exchange has an exception, show the exception message (no stacktrace) |
false |
boolean |
showExchangeId (formatting) |
Show the unique exchange ID. |
false |
boolean |
showExchangePattern (formatting) |
Shows the Message Exchange Pattern (or MEP for short). |
true |
boolean |
showFiles (formatting) |
If enabled Camel will output files |
false |
boolean |
showFuture (formatting) |
If enabled Camel will on Future objects wait for it to complete to obtain the payload to be logged. |
false |
boolean |
showHeaders (formatting) |
Show the message headers. |
false |
boolean |
showOut (formatting) |
If the exchange has an out message, show the out message. |
false |
boolean |
showProperties (formatting) |
Show the exchange properties. |
false |
boolean |
showStackTrace (formatting) |
Show the stack trace, if an exchange has an exception. Only effective if one of showAll, showException or showCaughtException are enabled. |
false |
boolean |
showStreams (formatting) |
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. |
false |
boolean |
skipBodyLineSeparator (formatting) |
Whether to skip line separators when logging the message body. This allows to log the message body in one line, setting this option to false will preserve any line separators from the body, which then will log the body as is. |
true |
boolean |
style (formatting) |
Sets the outputs style to use. |
Default |
OutputStyle |
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"
Masking sensitive information like password
Since Camel 2.19
You can enable security masking for logging by setting logMask
flag to true
.
Note that this option also affects Log EIP.
To enable mask in Java DSL at CamelContext level:
camelContext.setLogMask(true);
And in XML:
<camelContext logMask="true">
You can also turn it on|off at endpoint level. To enable mask in Java DSL at endpoint level, add logMask=true option in the URI for the log endpoint:
from("direct:start").to("log:foo?logMask=true");
And in XML:
<route>
<from uri="direct:foo"/>
<to uri="log:foo?logMask=true"/>
</route>
org.apache.camel.processor.DefaultMaskingFormatter
is used for the masking by default.
If you want to use a custom masking formatter, put it into registry with the name CamelCustomLogMask
.
Note that the masking formatter must implement org.apache.camel.spi.MaskingFormatter
.
Full customization of the logging output
Since 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 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.
-
… etc.
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" />
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 "logFormatter" 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&param2=100"/>
<to uri="log:bar?param1=bar&param2=200"/>
Using Log component in OSGi
Improvement as of Camel 2.12.4/2.13.1
When using Log component inside OSGi (e.g., in Karaf), the underlying
logging mechanisms are provided by PAX logging. It searches for a bundle
which invokes org.slf4j.LoggerFactory.getLogger()
method and
associates the bundle with the logger instance. Without specifying
custom org.sfl4j.Logger
instance, the logger created by Log component
is associated with camel-core
bundle.
In some scenarios it is required that the bundle associated with logger
should be the bundle which contains route definition. To do this, either
register single instance of org.slf4j.Logger
in the Registry or
reference it using logger
URI parameter.