Re: A "Kamel" crazy idea
Awesome idea. Seeing this being viable in a platform like Apache OpenWhisk
would be great too. I keep hearing customers asking about lightweight
containers to run Camel context. :)
On Fri, Jul 13, 2018 at 5:31 AM, Antonin Stefanutti <antonin@xxxxxxxxxxxxx>
> Hi Nicola,
> I love the idea.
> I just wonder whether YAML/JSON is an expressive enough format in the long
> term. But as you’ve mentioned, starting simple would enable experimenting
> some very interesting / promising optimisations. So it seems worth taking
> that path, instead of trying to embed a complex DSL or the existing XML DSL
> into the CRD.
> Definitely +1
> > On 13 Jul 2018, at 01:30, Nicola Ferraro <ni.ferraro@xxxxxxxxx> wrote:
> > Hi Cameleers,
> > it's now passed some time since I started thinking about a new project
> > we can begin here at Apache Camel, and I'd like to have your opinion.
> > We've already been targeting cloud-native applications with Camel,
> > especially on top of Kubernetes, that is becoming "the standard" cloud
> > platform. But writing a Camel integration and running it on Kubernetes
> > requires some effort: choosing the base platform (spring-boot, karaf,
> > simple main?), adding health checks (actuator?), packaging a docker image
> > and creating the Kubernetes resources (fabric8-maven-plugin, helm?),
> > publishing the image on a docker registry, then finally deploying the
> > resources on a Kubernetes cluster.
> > The resulting integration container is then far from being optimal from a
> > resource consumption point of view: it is likely that a Camel Spring-Boot
> > application will require at least 200MB of RAM and also some CPU shares
> > because of polling threads used by many components.
> > In case people use a CI/CD pipeline, it will take also a long time to get
> > from a code update to having a Kubernetes POD up and running.
> > Apart from compilation and image push/pull time, also startup time is
> > ~10 seconds for Camel + Spring-Boot in a container with standard limits
> > resources, making it difficult to propose this combination for
> > integration" (this term is becoming increasingly more popular).
> > So, my proposal is to start to investigate a "more cloud-native" approach
> > to integration: *making Camel integrations first-class citizens in
> > Kubernetes, and making them super fast and lightweight.*
> > We can base the project on Kubernetes Custom Resource Definitions (CRD)
> > <https://kubernetes.io/docs/concepts/extend-kubernetes/
> > for example a Integration CRD and have a Kubernetes "operator"
> > <https://coreos.com/operators/> taking care of:
> > - Optimizing the integration that we want to run
> > - Packaging in a container
> > - Running it on Kubernetes
> > - Managing its entire lifecycle
> > A Kubernetes-native integration may look like:
> > -------------------
> > kind: "Integration"
> > apiVersion: "camel.apache.org/v1alpha1"
> > metadata:
> > name: "example"
> > spec:
> > replicas: 1
> > routes:
> > - id: timer
> > route:
> > - type: endpoint
> > uri: timer:tick
> > - type: endpoint
> > uri: log:info
> > -------------------
> > For those who are not familiar with Kubernetes resources, this kind of
> > YAML/JSON resource definitions are really common.
> > The example route is embedded in the Kubernetes resource declaration and
> > follows a basic "flow DSL". We may start from a basic one and evolve it
> > new requirements arrive from the community.
> > I've made a very simple (but working) POC here:
> > https://github.com/nicolaferraro/integration-operator.
> > This idea of a "Cloud-Native Camel" on Kubernetes (project codename can
> be "
> > *Kamel*", if you like it :D), will be an enabler for a lot of nice
> > For example, we can propose "Kamel" as "ideal" platform for "serverless
> > integration" (I see many people reinventing the wheel out there): the
> > operator can reduce resource consumption of a single integration by
> > optimizing the runtime and also pause/resume integrations when they are
> > used, that is the basic idea behind "serverless" (e.g. think to
> > HTTP-triggered integrations, but not only).
> > Focusing on serverless will bring more emphasis on push-based
> > (webhooks, cloud events <https://cloudevents.io/>), that are rarely
> used in
> > Camel components, that prefer a poll based approach being it simpler to
> > in classic deployments, but not so good in the cloud, where more
> > become higher direct costs for the users.
> > The presence of the simplified DSL enables also experimenting on
> > subsets of Camel" implemented in languages other than Java, for example
> > language that has a reactive approach on thread scheduling and a really
> > memory footprint, like Go.
> > But apart from this kind of experiments (that are valid IMO), the "Kamel"
> > optimizer will have free room to choose the right platform for the
> > integration that the user wants to run, including, in the future, doing
> > compilation using Graal/VM (less memory, faster startup) if the features
> > (components) used in the integration are supporting it (maybe we can add
> > AOT compilation in the roadmap for Camel 3).
> > A silly optimization: integrations starting from "timer:..." may be
> > scheduled directly with Kubernetes CronJobs, so they will consume
> > only when actually running.
> > Being the final integrations lightweight and being the DSL
> > language-independent, we may see a increased adoption of Camel also as
> > agile integration layer for not-only-java applications (both "cloud" and
> > "serverless" applications).
> > I'm the first one that would like to work on a project ilke this. I've
> > worked on many Kubernetes/Openshift based applications and frameworks in
> > the past years, also on operators and CRDs, and I think this way of
> > redesigning integrations has a lot of potential.
> > Integrations will not be necessarily limited to the simplified DSL, but
> > can add extension points for scripting and even custom libraries
> > limiting the freedom of the optimizer).
> > The most important thing: it may become a great project, since it's
> > by a great community.
> > So, what do you think? Is it crazy enough?
> > Nicola