Announcing OpenFunction 0.8.0: Speed up function launching with Dapr Proxy

One of the unique features of OpenFunction is its simple integration with various backend services (BaaS) through Dapr. Currently, OpenFunction supports Dapr pub/sub and bindings building blocks, and more will be added in the future.

In OpenFunction v0.7.0 and versions prior to v0.7.0, OpenFunction integrates with BaaS by injecting a dapr sidecar container into each function instance’s pod, which leads to the following problems:

  • The entire function instance’s launch time is slowed down by the launching of the dapr sidecar container.
  • The dapr sidecar container may consume more resources than the function container itself.

To address the problems above, OpenFunction introduces the Dapr Standalone Mode in v0.8.0.

Dapr Standalone Mode

In Dapr standalone mode, one Dapr Proxy service will be created for each function which is then shared by all instances of this function. This way, there is no need to launch a seperate Dapr sidecar container for each function instance anymore which reduces the function launching time significantly.

Choose the appropriate Dapr Service Mode

So now you’ve 2 options to integrate with BaaS:

  • Dapr Sidecar Mode
  • Dapr Standalone Mode

You can choose the appropriate Dapr Service Mode for your functions. The Dapr Standalone Mode is the recommened and default mode. You can use Dapr Sidecar Mode if your function doesn’t scale frequently or you’ve difficulty to use the Dapr Standalone Mode.

You can control how to integrate with BaaS with 2 flags, both can be set in function’s spec.serving.annotations:

  • can be set to true or false
  • can be set to standalone or sidecar
  • When is set to true, users can choose the Dapr Service Mode by setting to standalone or sidecar.
  • When is set to false, the value of will be ignored and neither Dapr Sidecar nor Dapr Proxy Service will be launched.

There’re default values for both of these two flags if they’re not set.

  • The value of will be set to true if it’s not defined in spec.serving.annotations and the function definition contains either spec.serving.inputs or spec.serving.outputs. Otherwise it will be set to false.
  • The default value of is standalone if not set.

Below you can find a function example to set these two flags:

kind: Function
  name: cron-input-kafka-output
    annotations: "true" "standalone"
        - name: function # DO NOT change this
          imagePullPolicy: IfNotPresent 
    runtime: "async"
      - name: cron
        component: cron
      - name: sample
        component: kafka-server
        operation: "create"

Here you can find more information about OpenFunction v0.8.0.

Announcing General Availability of OpenFunction 0.7.0

OpenFunction is a cloud-native open-source FaaS (Function as a Service) platform aiming to let you focus on your business logic only. Today, we are thrilled to announce the general availability of OpenFunction 0.7.0.

Thanks to your contributions and feedback, OpenFunction 0.7.0 brings more exciting features like OpenFunction Gateway, async and sync functions of Java and Node.js, and Helm installation. Meantime, OpenFunction dependencies have been upgraded for better user experience.

OpenFunction Gateway

Starting from OpenFunction 0.5.0, OpenFunction uses Kubernetes Ingress to provide a unified entry for sync functions, and an Nginx ingress controller must be installed.

With the maturity of the Kubernetes Gateway API, we decided to implement OpenFunction Gateway based on the Kubernetes Gateway API to replace the previous ingress-based domain method in OpenFunction 0.7.0.

OpenFunction Gateway provides a more powerful and more flexible function gateway, including the following features:

  • Enable users to switch to any gateway implementations that support Kubernetes Gateway API such as Contour, Istio, Apache APISIX, Envoy Gateway (in the future) and more in an easier and vendor-neutral way.

  • Users can choose to install a default gateway implementation (Contour) and then define a new or use any existing gateway implementations in their environment and then reference an existing

  • Allow users to customize their own function access pattern like hostTemplate: "{{.Name}}.{{.Namespace}}.{{.Domain}}" for host-based access.

  • Allow users to customize their own function access pattern like pathTemplate: "{{.Namespace}}/{{.Name}}" for path-based access.

  • Allow users to customize each function’s route rules (host-based, path-based or both) in the function definition and default route rules are provided for each function if there’re no customized route rules defined.

  • Access functions from outside of the cluster. You only need to configure a valid domain name in OpenFunction Gateway. Both Magic DNS and Real DNS are supported.

  • Send traffic to Knative service revisions directly without going through Knative’s own gateway anymore. You will need only OpenFunction Gateway since OpenFunction 0.7.0 to access OpenFunction sync functions, and you can ignore Knative’s domain config errors if you do not need to access Knative service directly.

In upcoming releases, OpenFunction will support traffic splitting between function revisions.

Support for multiple programming languages

The OpenFunction community has been striving to support more programming languages:

  • Go

    functions-framework-go 0.4.0 supports the ability to define multiple sub-functions in one function and call the sub-functions through different Paths and Methods.

  • Java

    functions-framework-java supports async and sync functions.

  • Node.js

    functions-framework-nodejs 0.5.0 supports async and sync functions, and the async functions can be triggered by the sync functions.

    OpenFunction will introduce more features in functions-framework-nodejs 0.6.0, such as add-ons and integration with SkyWalking.

OpenFunction will support more programming languages, such as Python and Dotnet.

Use Helm to install OpenFunction and its dependencies

Previously, we use CLI to install OpenFunction and its dependencies. Now, this method has been depreciated.

In OpenFunction 0.7.0., we use Helm to install OpenFunction and its dependencies, which is more cloud-native and solves the problem that some users are unable to access Google Container Registry (


helm repo add openfunction
helm repo update
helm install openfunction openfunction/openfunction -n openfunction --create-namespace

Upgrade dependencies

ComponentsOpenFunction 0.6.0OpenFunction 0.7.0
Knative Serving1.
Tekton Pipelines0.

Announcing OpenFunction 0.6.0: FaaS observability, HTTP trigger, and more

OpenFunction is a cloud-native open source FaaS platform aiming to let you focus on your business logic. The OpenFunction community has been hard at work over the past several months preparing for the OpenFunction 0.6.0 release. Today, we proudly announce OpenFunction 0.6.0 is officially available. Thanks to the community for helping drive the new features, enhancements, and bug fixes.

OpenFunction 0.6.0 brings notable features including function plugin, distributed tracing for functions, control autoscaling behavior, HTTP trigger to async function, etc. Meanwhile, asynchronous runtime definition has also been refactored. The core API has been upgraded from v1alpha1 to v1beta1.

Distributed tracing for serverless functions

When trying to understand and diagnose the distributed systems and microservices, one of the most effective methods is the stack trace. Distributed tracing provides a holistic view of the way that messages flow and distributed transaction monitoring for Serverless functions. The OpenFunction team collaborates with the Apache SkyWalking community to add FaaS observability which allows you to visualize function dependencies and track function invocations on SkyWalking UI.


Going forward, OpenFunction will add more capabilities for serverless functions in logging, metrics, and tracing. You will be able to use Apache SkyWalking and OpenFunction to set up a full-stack APM for your serverless workloads out-of-the-box. Moreover, OpenFunction will support OpenTelemetry that allows you to leverage Jaeger or Zipkin as an alternative.

Support Dapr pub/sub and bindings

Dapr bindings allows you to trigger your applications or services with events coming in from external systems, or interface with external systems. OpenFunction 0.6.0 adds Dapr output bindings to its synchronous functions which enables HTTP triggers for asynchronous functions. For example, synchronous functions backed by the Knative runtime can now interact with middlewares defined by Dapr output binding or pub/sub, and an asynchronous function will be triggered by the events sent from the synchronous function. See this guide for the quickstart sample.

​​Asynchronous function introduces Dapr pub/sub to provide a platform-agnostic API to send and receive messages. A typical use case is that you can leverage synchronous functions to receive an event in plain JSON or Cloud Events format, and then send the received event to a Dapr output binding or pub/sub component, most likely a message queue (e.g. Kafka, NATS Streaming, GCP PubSub). Finally, the asynchronous function could be triggered from the message queue. See this guide for the quickstart sample.


Control autoscaling behavior for functions

OpenFunction 0.6.0 integrates KEDA ScaledObject spec which is used to define how KEDA should scale your application and what the triggers are. You just need to define the lower and upper bound in the function CRD without changing your code.

Meanwhile, the OpenFunction community is also developing the ability to control the concurrency and the number of simultaneous requests, which inherits the definition from Dapr and Knative. A typical use case in distributed computing is to only allow for a given number of requests to execute concurrently. You will be able to control how many requests and events will invoke your application simultaneously. This feature will be totally supported in the next release, stay tune! If you are interested in this feature, check out the active discussion for detailed context.

Learn by doing

Benjamin Huo, the founder of OpenFunction, has presented two typical use cases of OpenFunction 0.6.0 in Dapr community meeting:

  1. HTTP trigger for asynchronous functions with OpenFunction and Kafka
  2. Elastic Kubernetes log alerts with OpenFunction and Kafka

Watch this video and follow with the hands-on guides to practice.

You can learn more about OpenFunction 0.6.0 from release notes. Get started with OpenFunction by following the Quick Start and samples.

Release v0.4.0

@wanjunlei wanjunlei released this on 2021.10.19

Release: v0.4.0

Release notes:


  • Upgrade from v1alpha1 to v1alpha2. #115
  • Make event handlers self driven. #115


  • Update dependent Dapr version to v1.3.1. #123
  • Update dependent Tekton pipeline version to 0.28.1. #131
  • Update dependent Knative serving version to 0.26.0. #131
  • Update dependent Shipwright build version to 0.6.0. #131
  • Update go version to 1.16. #131
  • Now Function supports environment variables with commas. #131


  • Fix bug rerun serving failed. #132


  • Use installation script to deploy OpenFunction and deprecate the installation guide. #122


  • Add OpenFunction Website. #1


  • Add OpenFunction CLI. #11


  • Upgrade the functions-framework-go from v0.0.0-20210628081257-4137e46a99a6 to v0.0.0-20210922063920-81a7b2951b8a. #17
  • Add Ruby builder. #11


  • Supports multiple input sources && Replace int return with ctx.Return. #13


  • Support OpenFunction type function. #7


  • Add handler functions. #7


Thanks to these contributors who contributed to v0.4.0!

@wanjunlei @benjaminhuo @tpiperatgod @linxuyalun @penghuima @lizzzcai

Release v0.3.1

@wanjunlei wanjunlei released this on 2021.8.27

Release: v0.3.1

Release notes:

  • Delete the old serving CR only after the new serving CR is running. #107

Release v0.3.0

@tpiperatgod tpiperatgod released this on 2021.8.19

Release: v0.3.0

Release notes:

Release v0.2.0

@benjaminhuo benjaminhuo released this on 2021.5.17

Release: v0.2.0

Release notes:

  • Support OpenFunctionAsync serving runtime(backed by Dapr + KEDA + Deployment/Job)
  • Functions framework supports async function now
  • Customized go function framework & builders for both Knative and OpenFunctionAsync serving runtime

Release v0.1.0

@benjaminhuo benjaminhuo released this on 2021.5.17

Release: v0.1.0

Release notes:

  • Add Function, Builder, and Serving CRDs and corresponding controllers
  • Support using existing function framework & buildpacks such as Google Cloud Functions to build functions
  • Support Tekton and Cloud Native Buildpacks as Builder backend
  • Support Knative as Serving backend
  • Optimize and localize existing function framework & buildpacks