VM component

The vm component is a seda queue shared by every CamelContext in the same process, so separately deployed route sets can pass messages in memory.

Scheme: vm: · Crate: cameleer-core · Cargo feature: none, always included (build features) · Consumer: yes · Producer: yes · Apache Camel: VM

When to use it

• Connect two CamelContexts embedded in one Rust program (for example a plugin's routes and the host's routes).
• Feed a shared audit or metrics route from several independent route sets.
• Kamelet Pipes map Knative Channel and Broker references to vm:<name>, an in-process channel.

URI format

vm:name[?options]

Example

- route:
    id: audit-publisher
    from:
      uri: direct:audit
      steps:
        - to: vm:audit
- route:
    id: audit-writer
    from:
      uri: vm:audit
      parameters:
        concurrentConsumers: 1
      steps:
        - log: "audit: ${body}"
        - to: log:audit

Any context in the process that sends to vm:audit reaches the audit-writer route.

Rust DSL

use cameleer_core::prelude::*;

pub fn routes(ctx: &CamelContext) -> Result<()> {
    ctx.add_routes(|b| {
        b.from("direct:audit").route_id("audit-publisher").to("vm:audit");
        b.from("vm:audit?concurrentConsumers=1")
            .route_id("audit-writer")
            .log("audit: ${body}")
            .to("log:audit");
    })
}

Options

vm takes exactly the same options as seda: size, concurrentConsumers, waitForTaskToComplete, timeout, multipleConsumers, blockWhenFull, discardWhenFull, offerTimeout, pollTimeout, purgeWhenStopping, failIfNoConsumers, discardIfNoConsumers, limitConcurrentConsumers.

Message headers

None added. The consumer gets a copy of the exchange with the property CamelCorrelationId.

Run it with Docker

docker run --rm -v "$PWD:/routes:ro" pmsudhi/cameleer run /routes/audit.camel.yaml

The container runs one context, so vm behaves like seda there.

Common questions

What is the difference between vm and seda?

A seda queue is visible only inside its own CamelContext. A vm queue with the same name is the same queue for every context in the process.

Can vm connect two separate processes or containers?

No. It is in memory. Use a broker (kafka, amqp, paho) between processes.

Related

• seda, direct, kamelet
• Apache Camel VM component

Found a problem?

If something on this page doesn't match what Cameleer does, or you hit a bug while building with it, please help fix it, whether you are a person or a coding agent: open an issue that describes what you saw, then fork the repository, fix it, add or update a test, run cargo test --workspace, and open a pull request. CONTRIBUTING.md explains the ground rules.