1 - Component Specifications

Learn about OpenFunction component specifications.

1.1 - Function Specifications

Learn about Function Specifications.

This document describes the specifications of the Function CRD.

Function.spec

NameTypeDescriptionRequired
imagestringImage upload path, e.g. demorepo/demofunction:v1true
buildobjectBuilder specification for the functionfalse
imageCredentialsobjectCredentials for accessing the image repository, refer to v1.LocalObjectReferencefalse
servingobjectServing specification for the functionfalse
versionstringFunction version, e.g. v1.0.0false
workloadRuntimestringWorkloadRuntime for Function. Know values: OCIContainer and WasmEdge.Default: OCIContainerfalse

Function.spec.build

↩ Parent

NameTypeDescriptionRequired
srcRepoobjectThe configuration of the source code repositorytrue
builderstringName of the Builderfalse
builderCredentialsobjectCredentials for accessing the image repository, refer to v1.LocalObjectReferencefalse
builderMaxAgestringThe maximum time of finished builders to retain.false
dockerfilestringPath to the Dockerfile instructing Shipwright when using the Dockerfile to build imagesfalse
envmap[string]stringEnvironment variables passed to the buildpacks builderfalse
failedBuildsHistoryLimitintegerThe number of failed builders to retain. Default is 1.false
shipwrightobjectSpecification of the Shipwright enginefalse
successfulBuildsHistoryLimitintegerThe number of successful finished builders to retain. Default is 0.false
timeoutstringThe maximum time for the builder to build the imagefalse

Function.spec.build.srcRepo

↩ Parent

NameTypeDescriptionRequired
bundleContainerobjectBundleContainer describes the source code bundle container to pullfalse
credentialsobjectRepository access credentials, refer to v1.LocalObjectReferencefalse
revisionstringReferencable instances in the repository, such as commit ID and branch name.false
sourceSubPathstringThe directory of the function in the repository, e.g. functions/function-a/false
urlstringSource code repository addressfalse

Function.spec.build.srcRepo.bundleContainer

↩ Parent

NameTypeDescriptionRequired
imagestringThe bundleContainer image nametrue

Function.spec.build.shipwright

↩ Parent

NameTypeDescriptionRequired
params[]objectParameters for the build strategyfalse
strategyobjectStrategy references the BuildStrategy to use to build the imagefalse
timeoutstringThe maximum amount of time the shipwright Build should take to executefalse

Function.spec.serving

↩ Parent

NameTypeDescriptionRequired
annotationsmap[string]stringAnnotations that will be added to the workloadfalse
bindingsmap[string]objectDapr bindings that the function needs to create and use.false
hooksobjectHooks that will be executed before or after the function executionfalse
labelsmap[string]stringLabels that will be added to the workloadfalse
outputs[]objectThe outputs which the function will send data tofalse
paramsmap[string]stringParameters required by the function, will be passed to the function as environment variablesfalse
pubsubmap[string]objectDapr pubsub that the function needs to create and usefalse
scaleOptionsobjectConfiguration of auto scaling.false
statesmap[string]objectDapr state store that the function needs to create and usefalse
templateobjectTemplate is a pod template which allows modifying operator generated pod template.false
timeoutstringTimeout defines the maximum amount of time the Serving should take to execute before the Serving is runningfalse
tracingobjectConfiguration of tracingfalse
triggersobjectTriggers used to trigger the function. Refer to Function Trigger.true
workloadTypestringThe type of workload used to run the function, known values are: Deployment, StatefulSet and Jobfalse

Function.spec.serving.hooks

↩ Parent

NameTypeDescriptionRequired
policystringThere are two kind of hooks, global hooks and private hooks, the global hooks define in the config file of OpenFunction Controller, the private hooks define in the Function. Policy is the relationship between the global hooks and the private hooks of the function. Known values are:
  Append: All hooks will be executed, the private pre hooks will execute after the global pre hooks , and the private post hooks will execute before the global post hooks. this is the default policy.
  Override: Only execute the private hooks.
false
post[]stringThe hooks will be executed after the function executionfalse
pre[]stringThe hooks will be executed before the function executionfalse

Function.spec.serving.outputs[index]

↩ Parent

NameTypeDescriptionRequired
daprobjectDapr output, refer to a exist component or a component defined in bindings or pubsubfalse

Function.spec.serving.outputs[index].dapr

↩ Parent

NameTypeDescriptionRequired
namestringThe name of the dapr componenttrue
metadatamap[string]stringMetadata passed to Daprfalse
operationstringOperation field tells the Dapr component which operation it should perform, refer to Dapr docsfalse
topicstringWhen the type is pubsub, you need to set the topicfalse
typestringType of Dapr component, such as: bindings.kafka, pubsub.rocketmqfalse

Function.spec.serving.scaleOptions

↩ Parent

NameTypeDescriptionRequired
kedaobjectConfiguration about keda autoscalingfalse
knativemap[string]stringKnative autiscaling annotations. Refer to Knative autoscaling.false
maxReplicasintegerMinimum number of replicas which will scale the resource down to. By default, it scales to 0.false
minReplicasintegerMaximum number of replicas which will scale the resource up to.false

Function.spec.serving.scaleOptions.keda

↩ Parent

NameTypeDescriptionRequired
scaledJobobjectScale options for jobfalse
scaledObjectobjectScale options for deployment and statefulsetfalse
triggers[]objectEvent sources that trigger dynamic scaling of workloads. Refer to kedav1alpha1.ScaleTriggers.false

Function.spec.serving.scaleOptions.keda.scaledJob

↩ Parent

NameTypeDescriptionRequired
failedJobsHistoryLimitintegerHow many failed jobs should be kept. It defaults to 100.false
pollingIntervalintegerThe pollingInterval is in seconds. This is the interval in which KEDA checks the triggers for the queue length or the stream lag. It defaults to 30 seconds.false
restartPolicystringRestart policy for all containers within the pod. Value options are OnFailure or Never. It defaults to Never.false
scalingStrategyobjectSelect a scaling strategy. Value options are default, custom, or accurate. The default value is default. Refer to kedav1alpha1.ScalingStrategyfalse
successfulJobsHistoryLimitintegerHow many completed jobs should be kept. It defaults to 100.false

Function.spec.serving.scaleOptions.keda.scaledObject

↩ Parent

NameTypeDescriptionRequired
advancedobjectThis property specifies whether the target resource (for example, Deployment and StatefulSet) should be scaled back to original replicas count after the ScaledObject is deleted. Default behavior is to keep the replica count at the same number as it is in the moment of ScaledObject deletion. Refer to kedav1alpha1.AdvancedConfig.false
cooldownPeriodintegerThe cooldownPeriod is in seconds, and it is the period of time to wait after the last trigger activated before scaling back down to 0. It defaults to 300 seconds.false
pollingIntervalintegerThe pollingInterval is in seconds. This is the interval in which KEDA checks the triggers for the queue length or the stream lag. It defaults to 30 seconds.false

Function.spec.serving.states[key]

↩ Parent

NameTypeDescriptionRequired
specobjectDapr state stroe component spec. Refer to Dapr docs.false

Function.spec.serving.tracing

↩ Parent

NameTypeDescriptionRequired
baggagemap[string]stringBaggage is contextual information that passed between spans. It is a key-value store that resides alongside span context in a trace, making values available to any span created within that trace.true
enabledbooleanWether to enable tracingtrue
providerobjectThe tracing implementation used to create and send spantrue
tagsmap[string]stringThe tag that needs to be added to the spansfalse

Function.spec.serving.tracing.provider

↩ Parent

NameTypeDescriptionRequired
namestringTracing provider name, known values are skywalking and opentelemetrytrue
exporterobjectService to collect span for opentelemetryfalse
oapServerstringThe skywalking server urlfalse

Function.spec.serving.tracing.provider.exporter

↩ Parent

NameTypeDescriptionRequired
endpointstringThe exporter urltrue
namestringThe exporter name, known values are otlp, jaeger, and zipkintrue
compressionstringThe compression type to use on OTLP trace requests. Options include gzip. By default no compression will be used.false
headersstringKey-value pairs separated by commas to pass as request headers on OTLP trace requests.false
protocolstringThe transport protocol to use on OTLP trace requests. Options include grpc and http/protobuf. Default is grpc.false
timeoutstringThe maximum waiting time, in milliseconds, allowed to send each OTLP trace batch. Default is 10000.false

Function.spec.serving.triggers

↩ Parent

NameTypeDescriptionRequired
dapr[]objectList of dapr triggers, refer to dapr bindings or pusub componentsfalse
httpobjectThe http triggerfalse
inputs[]objectA list of components that the function can get data fromfalse

Function.spec.serving.triggers.dapr[index]

↩ Parent

NameTypeDescriptionRequired
namestringThe dapr component nametrue
topicstringWhen the component type is pubsub, you need to set the topicfalse
typestringType of Dapr component, such as: bindings.kafka, pubsub.rocketmqfalse

Function.spec.serving.triggers.http

↩ Parent

NameTypeDescriptionRequired
portintegerThe port the function is listening on, e.g. 8080false
routeobjectRoute defines how traffic from the Gateway listener is routed to a function.false

Function.spec.serving.triggers.http.route

↩ Parent

NameTypeDescriptionRequired
gatewayRefobjectGatewayRef references the Gateway resources that a Route wantsfalse
hostnames[]stringHostnames defines a set of hostname that should match against the HTTP Host header to select a HTTPRoute to process the request.false
rules[]objectRules are a list of HTTP matchers, filters and actions. Refer to HTTPRouteRule.false

Function.spec.serving.triggers.http.route.gatewayRef

↩ Parent

NameTypeDescriptionRequired
namestringThe name of the gatewaytrue
namespacestringThe namespace of the gatewaytrue

Function.spec.serving.triggers.inputs[index]

↩ Parent

NameTypeDescriptionRequired
daprobjectA dapr component that function can get data from. Now just support dapr state storetrue

Function.spec.serving.triggers.inputs[index].dapr

↩ Parent

NameTypeDescriptionRequired
namestringThe dapr component name, maybe a exist component or a component defined in statetrue
typestringThe dapr component type, such as state.redisfalse

1.2 - EventSource Specifications

Learn about EventSource Specifications.

1.2.1 - EventSource Specifications

EventSource Specifications.

This document describes the specifications of the EventSource CRD.

EventSource

FieldDescription
apiVersion stringevents.openfunction.io/v1alpha1
kind stringEventSource
metadata v1.ObjectMeta(Optional) Refer to v1.ObjectMeta
spec EventSourceSpecRefer to EventSourceSpec
status EventSourceStatusStatus of EventSource

EventSourceSpec

Belong to EventSource.

FieldDescription
eventBus string(Optional) Name of the EventBus resource associated with the event source.
redis map[string]RedisSpec(Optional) The definition of a Redis event source, with key being the event name, refer to RedisSpec.
kafka map[string]KafkaSpec(Optional) The definition of a Kafka event source, with key being the event name, refer to KafkaSpec.
cron map[string]CronSpec(Optional) The definition of a Cron event source, with key being the event name, refer to CronSpec.
sink SinkSpec(Optional) Definition of the Sink (addressable access resource, i.e. synchronization request) associated with the event source, cf. SinkSpec.

SinkSpec

Belong to EventSourceSpec.

FieldDescription
ref ReferenceRefer to Reference.

Reference

Belong to SinkSpec.

FieldDescription
kind stringThe type of the referenced resource. It defaults to Service.
namespace stringThe namespace of the referenced resource, by default the same as the namespace of the Trigger.
name stringName of the referenced resource, for example, function-ksvc.
apiVersion stringThe apiVersion of the referenced resource. It defaults to serving.knative.dev/v1.

GenericScaleOption

Belong to scaleOption.

FieldDescription
pollingInterval intThis is the interval to check each trigger on. It defaults to 30 seconds.
cooldownPeriod intThe period to wait after the last trigger reported active before scaling the resource back to 0. It defaults to 300 seconds.
minReplicaCount intMinimum number of replicas KEDA will scale the resource down to. It defaults to 0.
maxReplicaCount intThis setting is passed to the HPA definition that KEDA will create for a given resource.
advanced kedav1alpha1.AdvancedConfigSee KEDA documentation.
metadata map[string]stringKEDA trigger’s metadata
authRef kedav1alpha1.ScaledObjectAuthRefEvery parameter you define in TriggerAuthentication definition does not need to be included in the metadata of the trigger for your ScaledObject definition. To reference a TriggerAuthentication from a ScaledObject you add the authenticationRef to the trigger, refer to KEDA documentation.

1.2.2 - Redis

Event source specifications of Redis.

RedisSpec

Belong to EventSourceSpec.

FieldDescription
redisHost stringAddress of the Redis server, e.g. localhost:6379.
redisPassword stringPassword for the Redis server, e.g. 123456.
enableTLS bool(Optional) Whether to enable TLS access, which defaults to false. Value options: true, false.
failover bool(Optional) Whether to enable the failover feature. Requires the sentinalMasterName to be set. It defaults to false. Value options: true, false.
sentinelMasterName string(Optional) The name of the sentinel master. Refer to Redis Sentinel Documentation.
redeliverInterval string(Optional) The interval for redeliver. It defaults to 60s. 0 means the redeliver mechanism is disabled. E.g. 30s
processingTimeout string(Optional) Message processing timeout. It defaults to 15s. 0 means timeout is disabled. E.g. 30s
redisType string(Optional) The type of Redis. Value options: node for single-node mode, cluster for cluster mode. It defaults to node.
redisDB int64(Optional) The database index to connect to Redis. Effective only if redisType is node. It defaults to 0.
redisMaxRetries int64(Optional) Maximum number of retries. It defaults to no retries. E.g. 5
redisMinRetryInterval string(Optional) Minimum backoff time for retries. The default value is 8ms. -1 indicates that the backoff time is disabled. E.g. 10ms
redisMaxRetryInterval string(Optional) Maximum backoff time for retries. The default value is 512ms. -1 indicates that the backoff time is disabled. E.g. 5s
dialTimeout string(Optional) Timeout to establish a new connection. It defaults to 5s.
readTimeout string(Optional) Read timeout. A timeout causes Redis commands to fail rather than wait in a blocking fashion. It defaults to 3s. -1 means disabled.
writeTimeout string(Optional) Write timeout. A timeout causes Redis commands to fail rather than wait in a blocking fashion. It defaults to consistent with readTimeout.
poolSize int64(Optional) Maximum number of connections. It defaults to 10 connections per runtime.NumCPU. E.g. 20
poolTimeout string(Optional) The timeout for the connection pool. The default is readTimeout + 1 second. E.g. 50s
maxConnAge string(Optional) Connection aging time. The default is not to close the aging connection. E.g. 30m
minIdleConns int64(Optional) The minimum number of idle connections to maintain to avoid performance degradation from creating new connections. It defaults to 0. E.g. 2
idleCheckFrequency string(Optional) Frequency of idle connection recycler checks. Default is 1m. -1 means the idle connection recycler is disabled. E.g. -1
idleTimeout string(Optional) Timeout to close idle client connections, which should be less than the server’s timeout. It defaults to 5m. -1 means disable idle timeout check. E.g. 10m

1.2.3 - Kafka

Event source specifications of Kafka.

KafkaSpec

Belong to EventSourceSpec.

FieldDescription
brokers stringA comma-separated string of Kafka server addresses, for example, localhost:9092.
authRequired boolWhether to enable SASL authentication for the Kafka server. Value options: true, false.
topic stringThe topic name of the Kafka event source, for example, topicA, myTopic.
saslUsername string(Optional) The SASL username to use for authentication. Only required if authRequired is true. For example, admin.
saslPassword string(Optional) The SASL user password for authentication. Only required if authRequired is true. For example, 123456.
maxMessageBytes int64(Optional) The maximum number of bytes a single message is allowed to contain. Default is 1024. For example, 2048.
scaleOption KafkaScaleOption(Optional) Kafka’s scale configuration.

KafkaScaleOption

Belong to KafkaSpec.

FieldDescription
GenericScaleOptionGeneric scale configuration.
consumerGroup stringKafka’s consumer group name.
topic stringTopic under monitoring, for example, topicA, myTopic.
lagThreshold stringThreshold for triggering scaling, in this case is the Kafka’s lag.

1.2.4 - Cron

Event source specifications of Cron.

CronSpec

Belong to EventSourceSpec.

FieldDescription
schedule stringRefer to Schedule format for a valid schedule format, for example, @every 15m.

1.3 - EventBus Specifications

Learn about EventBus Specifications.

1.3.1 - EventBus Specifications

EventBus Specifications.

This document describes the specifications of the EventBus (ClusterEventBus) CRD.

EventBus (ClusterEventBus)

FieldDescription
apiVersion stringevents.openfunction.io/v1alpha1
kind stringEventBus(ClusterEventBus)
metadata v1.ObjectMeta(Optional) Refer to v1.ObjectMeta
spec EventBusSpecRefer to EventBusSpec
status EventBusStatusStatus of EventBus(ClusterEventBus)

EventBusSpec

Belong to EventBus.

FieldDescription
topic stringThe topic name of the event bus.
natsStreaming NatsStreamingSpecDefinition of the Nats Streaming event bus (currently only supported). See NatsStreamingSpec.

GenericScaleOption

Belong to scaleOption.

FieldDescription
pollingInterval intThe interval to check each trigger on. It defaults to 30 seconds.
cooldownPeriod intThe period to wait after the last trigger reported active before scaling the resource back to 0. It defaults to 300 seconds.
minReplicaCount intMinimum number of replicas which KEDA will scale the resource down to. It defaults to 0.
maxReplicaCount intThis setting is passed to the HPA definition that KEDA will create for a given resource.
advanced kedav1alpha1.AdvancedConfigSee KEDA documentation.
metadata map[string]stringKEDA trigger’s metadata.
authRef kedav1alpha1.ScaledObjectAuthRefEvery parameter you define in TriggerAuthentication definition does not need to be included in the metadata of the trigger for your ScaledObject definition. To reference a TriggerAuthentication from a ScaledObject, add the authRef to the trigger. Refer to KEDA documentation.

1.3.2 - NATS Streaming

Event bus specifications of NATS Streaming.

NatsStreamingSpec

Belong to EventBusSpec.

FieldDescription
natsURL stringNATS server address, for example, nats://localhost:4222.
natsStreamingClusterID stringNATS cluster ID, for example, stan.
subscriptionType stringSubscriber type, value options: topic, queue.
ackWaitTime string(Optional) Refer to Acknowledgements , for example, 300ms.
maxInFlight int64(Optional) Refer to Max In Flight , for example, 25.
durableSubscriptionName string(Optional) The name of the persistent subscriber. For example, my-durable.
deliverNew bool(Optional) Subscriber options (only one can be used). Whether to send only new messages. Value options: true, false.
startAtSequence int64(Optional) Subscriber options (only one can be used). Set the starting sequence position and status. For example, 100000.
startWithLastReceived bool(Optional) Subscriber options (only one can be used). Whether to set the start position to the latest news place. Value options: true, false.
deliverAll bool(Optional) Subscriber options (only one can be used). Whether to send all available messages. Value options: true, false.
startAtTimeDelta string(Optional) Subscriber options (only one can be used). Use the difference form to set the desired start time position and state, for example, 10m, 23s.
startAtTime string(Optional) Subscriber options (only one can be used). Set the desired start time position and status using the marker value form. For example, Feb 3, 2013 at 7:54pm (PST).
startAtTimeFormat string(Optional) Must be used with startAtTime. Sets the format of the time. For example, Jan 2, 2006 at 3:04pm (MST).
scaleOption NatsStreamingScaleOption(Optional) Nats streaming’s scale configuration.

NatsStreamingScaleOption

Belong to NatsStreamingSpec.

FieldDescription
GenericScaleOptionGeneric scale configuration.
natsServerMonitoringEndpoint stringNats streaming’s monitoring endpoint.
queueGroup stringNats streaming’s queue group name.
durableName stringNats streaming’s durable name.
subject stringSubject under monitoring, for example, topicA, myTopic.
lagThreshold stringThreshold for triggering scaling, in this case is the Nats Streaming’s lag.

1.4 - Trigger Specifications

Learn about Trigger Specifications.

This document describes the specifications of the Trigger CRD.

Trigger

FieldDescription
apiVersion stringevents.openfunction.io/v1alpha1
kind stringTrigger
metadata v1.ObjectMeta(Optional) Refer to v1.ObjectMeta
spec TriggerSpecRefer to TriggerSpec
status TriggerStatusStatus of Trigger

TriggerSpec

Belong to Trigger.

FieldDescription
eventBus string(Optional) Name of the EventBus resource associated with the Trigger.
inputs map[string]Input(Optional) The input of trigger, with key being the input name. Refer to Input.
subscribers []Subscriber(Optional) The subscriber of the trigger. Refer to Subscriber.

Input

Belong to TriggerSpec.

FieldDescription
namespace string(Optional) The namespace name of the EventSource, which by default matches the namespace of the Trigger, for example, default.
eventSource stringEventSource name, for example, kafka-eventsource.
event stringEvent name, for example, eventA.

Subscriber

Belong to TriggerSpec.

FieldDescription
condition stringTrigger conditions for triggers, refer to cel-spec for more writing specifications, for example, eventA && eventB or `eventA
sink SinkSpec(Optional) Triggered Sink (addressable access resource, for example, synchronization request) definition, refer to SinkSpec.
deadLetterSink SinkSpec(Optional) Triggered dead letter Sink (addressable access resource, for example, synchronization request) definition, refer to SinkSpec.
topic string(Optional) Used to send post-trigger messages to the specified topic of the event bus, for example, topicTriggered.
deadLetterTopic string(Optional) Used to send post-trigger messages to the specified dead letter topic of the event bus, for example, topicDL.

SinkSpec

Belong to EventSourceSpec.

FieldDescription
ref ReferenceRefer to Reference.

Reference

Belong to SinkSpec.

FieldDescription
kind stringThe type of the referenced resource. It defaults to Service.
namespace stringThe namespace of the referenced resource, by default the same as the namespace of the Trigger.
name stringName of the referenced resource, for example, function-ksvc.
apiVersion stringThe apiVersion of the referenced resource. It defaults to serving.knative.dev/v1.

2 - FAQ

This document describes FAQs when using OpenFunction.

Q: How to use private image repositories in OpenFunction?

A: OpenFunction uses Shipwright (which utilizes Tekton to integrate with Cloud Native Buildpacks) in the build phase to package the user function to the application image.

Users often choose to access a private image repository in an insecure way, which is not yet supported by the Cloud Native Buildpacks.

We offer a workaround as below to get around this limitation for now:

  1. Use IP address instead of hostname as access address for private image repository.
  2. You should skip tag-resolution when you run the Knative-runtime function.

For references:

buildpacks/lifecycle#524

buildpacks/tekton-integration#31

Q: How to access the Knative-runtime function without introducing a new ingress controller?

A: OpenFunction provides a unified entry point for function accessibility, which is based on the Ingress Nginx implementation. However, for some users, this is not necessary, and instead, introducing a new ingress controller may affect the current cluster.

In general, accessible addresses are for the sync(Knative-runtime) functions. Here are two ways to solve this problem:

  • Magic DNS

    You can follow this guide to config the DNS.

  • CoreDNS

    This is similar to using Magic DNS, with the difference that the configuration for DNS resolution is placed inside CoreDNS. Assume that the user has configured a domain named “openfunction.dev” in the ConfigMap config-domain under the knative-serving namespace (as shown below):

    $ kubectl -n knative-serving get cm config-domain -o yaml
    
    apiVersion: v1
    data:
      openfunction.dev: ""
    kind: ConfigMap
    metadata:
      annotations:
        knative.dev/example-checksum: 81552d0b
      labels:
        app.kubernetes.io/part-of: knative-serving
        app.kubernetes.io/version: 1.0.1
        serving.knative.dev/release: v1.0.1
      name: config-domain
      namespace: knative-serving
    

    Next, let’s add an A record for this domain. OpenFunction uses Kourier as the default network layer for Knative Serving, which is where the domain should flow to.

    $ kubectl -n kourier-system get svc
    
    NAME               TYPE           CLUSTER-IP     EXTERNAL-IP   PORT(S)                      AGE
    kourier            LoadBalancer   10.233.7.202   <pending>     80:31655/TCP,443:30980/TCP   36m
    kourier-internal   ClusterIP      10.233.47.71   <none>        80/TCP                       36m
    

    Then the user only needs to configure this Wild-Card DNS resolution in CoreDNS to resolve the URL address of any Knative Service in the cluster.

    Where “10.233.47.71” is the address of the Service kourier-internal.

    $ kubectl -n kube-system get cm coredns -o yaml
    
    apiVersion: v1
    data:
      Corefile: |
        .:53 {
            errors
            health
            ready
            template IN A openfunction.dev {
              match .*\.openfunction\.dev
              answer "{{ .Name }} 60 IN A 10.233.47.71"
              fallthrough
            }
            kubernetes cluster.local in-addr.arpa ip6.arpa {
              pods insecure
              fallthrough in-addr.arpa ip6.arpa
            }
            hosts /etc/coredns/NodeHosts {
              ttl 60
              reload 15s
              fallthrough
            }
            prometheus :9153
            forward . /etc/resolv.conf
            cache 30
            loop
            reload
            loadbalance
        }
        ...
    

    If the user cannot resolve the URL address for this function outside the cluster, configure the hosts file as follows:

    Where “serving-sr5v2-ksvc-sbtgr.default.openfunction.dev” is the URL address obtained from the command “kubectl get ksvc”.

    10.233.47.71 serving-sr5v2-ksvc-sbtgr.default.openfunction.dev
    

After the above configuration is done, you can get the URL address of the function with the following command. Then you can trigger the function via curl or your browser.

$ kubectl get ksvc

NAME                       URL
serving-sr5v2-ksvc-sbtgr   http://serving-sr5v2-ksvc-sbtgr.default.openfunction.dev

Q: How to enable and configure concurrency for functions?

A: OpenFunction categorizes function types into “sync runtime” and “async runtime” based on the type of request being handled. These two types of functions are driven by Knative Serving and Dapr + KEDA.

Therefore, to enable and configure the concurrency of functions, you need to refer to the specific implementation in the above components.

The following section describes how to enable and configure concurrency of functions in OpenFunction according to the “sync runtime” and “async runtime” sections.

Sync runtime

You can start by referring to this document in Knative Serving on enabling and configuring concurrency capabilities.

Knative Serving has Soft limit and Hard limit configurations for the concurrency feature.

Soft limit

You can refer to the Global(ConfigMap) and Global(Operator) sections of this document to configure global concurrency capabilities.

And for Per Revision you can configure it like this.

apiVersion: core.openfunction.io/v1beta2
kind: Function
metadata:
  name: function-sample
spec:
  serving:
    scaleOptions:
      knative:
        autoscaling.knative.dev/target: "200"

Hard limit

OpenFunction currently doesn’t support configuring Hard limit for Per Revision. You can refer to the Global(ConfigMap) and Global(Operator) sections of this document to configure global concurrency capabilities.

In summary

In a nutshell, you can configure Knative Serving’s Autoscaling-related configuration items for each function as follows, just as long as they can be passed in as Annotation, otherwise, you can only do global settings.

# Configuration in Knative Serving
apiVersion: serving.knative.dev/v1
kind: Service
metadata:
  name: helloworld-go
  namespace: default
spec:
  template:
    metadata:
      annotations:
        autoscaling.knative.dev/<key>: "value"

# Configuration in OpenFunction (recommended)
apiVersion: core.openfunction.io/v1beta2
kind: Function
metadata:
  name: function-sample
spec:
  serving:
    scaleOptions:
      knative:
          <key>: "value"

# Alternative approach
apiVersion: core.openfunction.io/v1beta2
kind: Function
metadata:
  name: function-sample
spec:
  serving:
    annotations:
      autoscaling.knative.dev/<key>: "value"

Async runtime

You can start by referring to the document in Dapr on enabling and configuring concurrency capabilities.

Compared to the concurrency configuration of sync runtime, the concurrency configuration of async runtime is simpler.

# Configuration in Dapr
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nodesubscriber
  namespace: default
spec:
  template:
    metadata:
      annotations:
        dapr.io/app-max-concurrency: "value"

# Configuration in OpenFunction (recommended)
apiVersion: core.openfunction.io/v1beta2
kind: Function
metadata:
  name: function-sample
spec:
  serving:
    annotations:
      dapr.io/app-max-concurrency: "value"

Q: How to create source repository credential for the function image build process?

A: You may be prompted with errors like Unsupported type of credentials provided, either SSH private key or username/password is supported (exit code 110) when using spec.build.srcRepo.credentials, which means you are using an incorrect Secret resource as source repository crendital.

OpenFunction currently implements the function image building framework based on ShipWright, so we need to refer to this document to setup the correct source repository credential.

Q: How to install OpenFunction in an offline environment?

A: You can install and use OpenFunction in an offline environment by following steps:

Pull the Helm Chart

Pull the helm chart in an environment that can access GitHub:

helm repo add openfunction https://openfunction.github.io/charts/
helm repo update
helm pull openfunction/openfunction

Then use tools like scp to copy the helm package to your offline environment, e.g.:

scp openfunction-v1.0.0-v0.5.0.tgz <username>@<your-machine-ip>:/home/<username>/

Synchronize images

You need to sync these images to your private image repository:

# dapr
docker.io/daprio/dashboard:0.10.0
docker.io/daprio/dapr:1.8.3

# keda
openfunction/keda:2.8.1
openfunction/keda-metrics-apiserver:2.8.1

# contour
docker.io/bitnami/contour:1.21.1-debian-11-r5
docker.io/bitnami/envoy:1.22.2-debian-11-r6
docker.io/bitnami/nginx:1.21.6-debian-11-r10

# tekton-pipelines
openfunction/tektoncd-pipeline-cmd-controller:v0.37.2
openfunction/tektoncd-pipeline-cmd-kubeconfigwriter:v0.37.2
openfunction/tektoncd-pipeline-cmd-git-init:v0.37.2
openfunction/tektoncd-pipeline-cmd-entrypoint:v0.37.2
openfunction/tektoncd-pipeline-cmd-nop:v0.37.2
openfunction/tektoncd-pipeline-cmd-imagedigestexporter:v0.37.2
openfunction/tektoncd-pipeline-cmd-pullrequest-init:v0.37.2
openfunction/tektoncd-pipeline-cmd-workingdirinit:v0.37.2
openfunction/cloudsdktool-cloud-sdk@sha256:27b2c22bf259d9bc1a291e99c63791ba0c27a04d2db0a43241ba0f1f20f4067f
openfunction/distroless-base@sha256:b16b57be9160a122ef048333c68ba205ae4fe1a7b7cc6a5b289956292ebf45cc
openfunction/tektoncd-pipeline-cmd-webhook:v0.37.2

# knative-serving
openfunction/knative.dev-serving-cmd-activator:v1.3.2
openfunction/knative.dev-serving-cmd-autoscaler:v1.3.2
openfunction/knative.dev-serving-cmd-queue:v1.3.2
openfunction/knative.dev-serving-cmd-controller:v1.3.2
openfunction/knative.dev-serving-cmd-domain-mapping:v1.3.2
openfunction/knative.dev-serving-cmd-domain-mapping-webhook:v1.3.2
openfunction/knative.dev-net-contour-cmd-controller:v1.3.0
openfunction/knative.dev-serving-cmd-default-domain:v1.3.2
openfunction/knative.dev-serving-cmd-webhook:v1.3.2

# shipwright-build
openfunction/shipwright-shipwright-build-controller:v0.10.0
openfunction/shipwright-io-build-git:v0.10.0
openfunction/shipwright-mutate-image:v0.10.0
openfunction/shipwright-bundle:v0.10.0
openfunction/shipwright-waiter:v0.10.0
openfunction/buildah:v1.23.3
openfunction/buildah:v1.28.0

# openfunction
openfunction/openfunction:v1.0.0
openfunction/kube-rbac-proxy:v0.8.0
openfunction/eventsource-handler:v4
openfunction/trigger-handler:v4
openfunction/dapr-proxy:v0.1.1
openfunction/revision-controller:v1.0.0

Create custom values

Create custom-values.yaml in your offline environment:

touch custom-values.yaml

Edit custom-values.yaml, add the following content:

knative-serving:
  activator:
    activator:
      image:
        repository: <your-private-image-repository>/knative.dev-serving-cmd-activator
  autoscaler:
    autoscaler:
      image:
        repository: <your-private-image-repository>/knative.dev-serving-cmd-autoscaler
  configDeployment:
    queueSidecarImage:
      repository: <your-private-image-repository>/knative.dev-serving-cmd-queue
  controller:
    controller:
      image:
        repository: <your-private-image-repository>/knative.dev-serving-cmd-controller
  domainMapping:
    domainMapping:
      image:
        repository: <your-private-image-repository>/knative.dev-serving-cmd-domain-mapping
  domainmappingWebhook:
    domainmappingWebhook:
      image:
        repository: <your-private-image-repository>/knative.dev-serving-cmd-domain-mapping-webhook
  netContourController:
    controller:
      image:
        repository: <your-private-image-repository>/knative.dev-net-contour-cmd-controller
  defaultDomain:
    job:
      image:
        repository: <your-private-image-repository>/knative.dev-serving-cmd-default-domain
  webhook:
    webhook:
      image:
        repository: <your-private-image-repository>/knative.dev-serving-cmd-webhook
shipwright-build:
  shipwrightBuildController:
    shipwrightBuild:
      image:
        repository: <your-private-image-repository>/shipwright-shipwright-build-controller
      GIT_CONTAINER_IMAGE:
        repository: <your-private-image-repository>/shipwright-io-build-git
      MUTATE_IMAGE_CONTAINER_IMAGE:
        repository: <your-private-image-repository>/shipwright-mutate-image
      BUNDLE_CONTAINER_IMAGE:
        repository: <your-private-image-repository>/shipwright-bundle
      WAITER_CONTAINER_IMAGE:
        repository: <your-private-image-repository>/shipwright-waiter
tekton-pipelines:
  controller:
    tektonPipelinesController:
      image:
        repository: <your-private-image-repository>/tektoncd-pipeline-cmd-controller
      kubeconfigWriterImage:
        repository: <your-private-image-repository>/tektoncd-pipeline-cmd-kubeconfigwriter
      gitImage:
        repository: <your-private-image-repository>/tektoncd-pipeline-cmd-git-init
      entrypointImage:
        repository: <your-private-image-repository>/tektoncd-pipeline-cmd-entrypoint
      nopImage:
        repository: <your-private-image-repository>/tektoncd-pipeline-cmd-nop
      imagedigestExporterImage:
        repository: <your-private-image-repository>/tektoncd-pipeline-cmd-imagedigestexporter
      prImage:
        repository: <your-private-image-repository>/tektoncd-pipeline-cmd-pullrequest-init
      workingdirinitImage:
        repository: <your-private-image-repository>/tektoncd-pipeline-cmd-workingdirinit
      gsutilImage:
        repository: <your-private-image-repository>/cloudsdktool-cloud-sdk
        digest: sha256:27b2c22bf259d9bc1a291e99c63791ba0c27a04d2db0a43241ba0f1f20f4067f
      shellImage:
        repository: <your-private-image-repository>/distroless-base
        digest: sha256:b16b57be9160a122ef048333c68ba205ae4fe1a7b7cc6a5b289956292ebf45cc
  webhook:
    webhook:
      image:
        repository: <your-private-image-repository>/tektoncd-pipeline-cmd-webhook
keda:
  image:
    keda:
      repository: <your-private-image-repository>/keda
      tag: 2.8.1
    metricsApiServer:
      repository: <your-private-image-repository>/keda-metrics-apiserver
      tag: 2.8.1
dapr:
  global:
    registry: <your-private-image-registry>/daprio
    tag: '1.8.3'
contour:
  contour:
    image:
      registry: <your-private-image-registry>
      repository: <your-private-image-repository>/contour
      tag: 1.21.1-debian-11-r5
  envoy:
    image:
      registry: <your-private-image-registry>
      repository: <your-private-image-repository>/envoy
      tag: 1.22.2-debian-11-r6
  defaultBackend:
    image:
      registry: <your-private-image-registry>
      repository: <your-private-image-repository>/nginx
      tag: 1.21.6-debian-11-r10

Install OpenFunction

Run the following command in an offline environment to try to install OpenFunction:

kubectl create namespace openfunction
helm install openfunction openfunction-v1.0.0-v0.5.0.tgz -n openfunction -f custom-values.yaml

Patch ClusterBuildStrategy

If you want to build wasm functions or use buildah to build functions in offline environment, run the following command to patch ClusterBuildStrategy:

kubectl patch clusterbuildstrategy buildah --type='json' -p='[{"op": "replace", "path": "/spec/buildSteps/0/image", "value":"openfunction/buildah:v1.28.0"}]'
kubectl patch clusterbuildstrategy wasmedge --type='json' -p='[{"op": "replace", "path": "/spec/buildSteps/0/image", "value":"openfunction/buildah:v1.28.0"}]'

Q: How to build and run functions in an offline environment

A: Let’s take Java functions as an example to illustrate how to build and run functions in an offline environment:

  • Synchronize https://github.com/OpenFunction/samples.git to your private code repository

  • Follow this prerequisites doc to create push-secret and git-repo-secret

  • Change public maven repository to private maven repository:

    <?xml version="1.0" encoding="UTF-8"?>
    <project xmlns="http://maven.apache.org/POM/4.0.0"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
        <modelVersion>4.0.0</modelVersion>
    
        <groupId>dev.openfunction.samples</groupId>
        <artifactId>samples</artifactId>
        <version>1.0-SNAPSHOT</version>
    
        <properties>
            <maven.compiler.source>11</maven.compiler.source>
            <maven.compiler.target>11</maven.compiler.target>
        </properties>
    
        <repositories>
            <repository>
                <id>snapshots</id>
                <name>Maven snapshots</name>
                    <!--<url>https://s01.oss.sonatype.org/content/repositories/snapshots/</url>-->
                    <url>your private maven repository</url>
                <releases>
                    <enabled>false</enabled>
                </releases>
                <snapshots>
                    <enabled>true</enabled>
                </snapshots>
            </repository>
        </repositories>
    
        <dependencies>
            <dependency>
                <groupId>dev.openfunction.functions</groupId>
                <artifactId>functions-framework-api</artifactId>
                <version>1.0.0-SNAPSHOT</version>
            </dependency>
        </dependencies>
    
    </project>
    

    Make sure to commit the changes to the code repo.

  • Synchronize openfunction/buildpacks-java18-run:v1 to your private image repository

  • Modify functions/knative/java/hello-world/function-sample.yaml according to your environment:

    apiVersion: core.openfunction.io/v1beta2
    kind: Function
    metadata:
      name: function-http-java
    spec:
      version: "v2.0.0"
      image: "<your private image repository>/sample-java-func:v1"
      imageCredentials:
        name: push-secret
      build:
        builder: <your private image repository>/builder-java:v2-18
        params:
          RUN_IMAGE: "<your private image repository>/buildpacks-java18-run:v1"
        env:
          FUNC_NAME: "dev.openfunction.samples.HttpFunctionImpl"
          FUNC_CLEAR_SOURCE: "true"
        srcRepo:
          url: "https://<your private code repository>/OpenFunction/samples.git"
          sourceSubPath: "functions/knative/java"
          revision: "main"
          credentials:
           name: git-repo-secret
      serving:
        template:
          containers:
            - name: function # DO NOT change this
              imagePullPolicy: IfNotPresent 
        triggers:
          http:
            port: 8080
    

    If your private mirror repository is insecure, please refer to Use private image repository in an insecure way

  • Run the following commands to build and run the function:

    kubectl apply -f functions/knative/java/hello-world/function-sample.yaml