5.7. Message History
Overview
The Message History from EIP pattern enables you to analyze and debug the flow of messages in a loosely coupled system. If you attach a message history to the message, it displays a list of all applications that the message passed through since its origination.
In Apache Camel, using the getTracedRouteNodes method, you can trace a message flow using the Tracer or access information using the Java API from UnitOfWork.
Limiting Character Length in Logs
When you run Apache Camel with logging mechanism, it enables you to log the messages and its content from time to time.
Some messages may contain very big payloads. By default, Apache Camel will clip the log message and show only the first 1000 characters. For example, it displays the following log as:
[DEBUG ProducerCache - >>>> Endpoint[direct:start] Exchange[Message: 01234567890123456789... [Body clipped after 20 characters, total length is 1000]
You can customize the limit when Apache Camel clips the body in the log. You can also set zero or a negative value, such as -1, means the message body is not logged.
- Customizing the Limit using Java DSL
- You can set the limit in Camel properties using Java DSL. For example,
context.getProperties().put(Exchange.LOG_DEBUG_BODY_MAX_CHARS, "500");
- Customizing the Limit using Spring DSL
- You can set the limit in Camel properties using Spring DSL. For example,
<camelContext> <properties> <property key="CamelLogDebugBodyMaxChars" value="500"/> </properties> </camelContext>
