Apache Camel 3.x Upgrade Guide
This document is for helping you upgrade your Apache Camel application from Camel 3.x to 3.y. For example if you are upgrading Camel 3.0 to 3.2, then you should follow the guides from both 3.0 to 3.1 and 3.1 to 3.2.
Upgrading Camel 3.3 to 3.4
=== camel-test and JMX
The camel-test
module no longer has dependency on camel-management
out of the box.
In Camel JMX is optional and to use JMX then camel-management
must be added as dependency.
For example to use JMX during testing you the following dependency as test scope:
<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-management</artifactId>
<scope>test</scope>
</dependency>
=== Template components
The template components which allows access to the current Exchange
and CamelContext
API
from the context map available for templating has now been restricted to only the message body and headers.
This option can be enabled (allowContextMapAll=true
) for full access to the current Exchange and CamelContext.
Doing so impose a potential security risk as this opens access to the full power of CamelContext API.
This applies to the following templating components: camel-freemarker, camel-velocity, camel-mvel, camel-mustache, camel-string-template, camel-chunk, camel-robotframework.
=== Using custom language in RouteBuilder
The Java DSL RouteBuilder
allows referring to a custom language as shown below:
from("direct:start")
.filter(language("foo", "Bla bla bla"))
.to("mock:camel");
This functionality is seldom in use, as you would use the provided languages from Camel.
If using, then the language
method now requires a static import as shown below:
import static org.apache.camel.builder.Builder.language;
=== camel-spring-boot
The /actuator/camelroutes
HTTP endpoint has been removed from provided Spring Boot actuators in camel-spring-boot
.
This actuator was becoming problematic to maintain during Spring Boot upgrades due to changes in Spring Boot.
=== camel-servlet and camel-http-common
HttpRegistry
and DefaultHttpRegistry
classes from camel-servlet are moved from camel-servlet into camel-http-common.
HttpRegistryProvider
is added and used in DefaultHttpRegistry
instead of CamelServlet
.
These changes had effects on camel-atmosphere-websocket and camel-servlet and also camel-resteasy.
Users of these components where they would have custom implemetations on DefaultHttpRegistry
and using CamelServlet
class should take this change into account.
=== camel-sql
The JdbcAggregationRepository
optimistic locking feature has been fixed to work on a distributed environment and every database.
There is a new version
column that is required and must be added to the repository:
CREATE TABLE aggregation (
id varchar(255) NOT NULL,
exchange blob NOT NULL,
version BIGINT NOT NULL,
constraint aggregation_pk PRIMARY KEY (id)
);
CREATE TABLE aggregation_completed (
id varchar(255) NOT NULL,
exchange blob NOT NULL,
version BIGINT NOT NULL,
constraint aggregation_completed_pk PRIMARY KEY (id)
);