Apache Camel 4.x Upgrade Guide

camel validate source and camel overview now use the same rules for a direct:, seda: or disruptor: endpoint that a route sends to and no route consumes, so they report the same endpoints on the same project:

So camel validate can report an endpoint it did not report before.

When a route marks the exchange rollback only (for example with markRollbackOnly() or markRollbackOnlyLast()) there is no exception on the exchange, and these consumers treated it as a success. The JPA consumer deleted the entity (or called its @Consumed method) and committed the poll, and the transacted (transacted=true) Hazelcast SEDA consumer committed its transaction, so the message was removed from the queue. Now a rollback only exchange is not consumed: the JPA consumer leaves the entity in the table, so the next poll consumes it again, as long as it still matches the query. With transacted=false the other entities of the poll are still consumed (without logging a WARN), and so is what a @PreConsumed method changed before routing; with transacted=true the whole poll is rolled back, as for a failed exchange. The Hazelcast SEDA consumer rolls back its transaction, so the message stays in the queue.

A message that the route marks rollback only every time was removed before, and is now consumed again at every poll (JPA), or taken from the queue again at once, without a delay (transacted Hazelcast SEDA, as for a failed exchange). Handle such a message in the route instead, for example by moving it aside, rather than marking it rollback only every time.

A hashicorp: property without an engine, such as {{hashicorp:mysecret}} or {{hashicorp:mysecret#field}}, now reads the secret from the secret engine. Before, it read from the engine of the hashicorp: property resolved before it (or from a null engine), and {{hashicorp:mysecret#field}} always resolved to no value. Properties with an engine, such as {{hashicorp:secret:mysecret#field}}, are not affected.

A hashicorp: property without an engine and with a version, such as {{hashicorp:mysecret@2}}, now reads version 2 of the secret mysecret in the secret engine. Before, the @2 was kept as part of the secret name.

A hashicorp: property with a field of a secret that does not exist, such as {{hashicorp:secret:missing#field}}, now resolves to no value, as it already did without a field, so its default value or an optional placeholder ({{?hashicorp:secret:missing#field}}) applies. Before, without a default value, it failed with a NullPointerException.

The validate and route-coverage goals read Java routes with the Java DSL parser of camel-java-io instead of camel-route-parser (Roaster). XML routes are read as before. The parser reads every configure() method of a source file, including those of a route builder created inside a test, so validate can find and validate endpoints it did not see before. An endpoint uri that is only a method call, such as from(inboxQueue()), is not validated (it was validated as a property placeholder without a component before); with logUnparseable=true it is logged.

The route-parser plugin (camel route-parser) and its camel-jbang-plugin-route-parser artifact are removed. Use camel cmd route-structure MyRoute.java instead: it prints the structure of the routes of a Java source, read without compiling it, and of YAML and XML sources too. If you installed the plugin, remove it with camel plugin delete route-parser.