docs/daprdocs/content/en/reference/components-reference/supported-pubsub/setup-jetstream.md

type	title	linkTitle	description	aliases
docs	JetStream	JetStream	Detailed documentation on the NATS JetStream component	/operations/components/setup-pubsub/supported-pubsub/setup-jetstream/

Component format

To setup JetStream pubsub create a component of type pubsub.jetstream. See [this guide]({{< ref "howto-publish-subscribe.md#step-1-setup-the-pubsub-component" >}}) on how to create and apply a pubsub configuration.

apiVersion: dapr.io/v1alpha1
kind: Component
metadata:
  name: jetstream-pubsub
spec:
  type: pubsub.jetstream
  version: v1
  metadata:
  - name: natsURL
    value: "nats://localhost:4222"
  - name: jwt # Optional. Used for decentralized JWT authentication.
    value: "eyJhbGciOiJ...6yJV_adQssw5c"
  - name: seedKey # Optional. Used for decentralized JWT authentication.
    value: "SUACS34K232O...5Z3POU7BNIL4Y"
  - name: tls_client_cert # Optional. Used for TLS Client authentication.
    value: "/path/to/tls.crt"
  - name: tls_client_key # Optional. Used for TLS Client authentication.
    value: "/path/to/tls.key"
  - name: token # Optional. Used for token based authentication.
    value: "my-token"
  - name: name
    value: "my-conn-name"
  - name: streamName
    value: "my-stream"
  - name: durableName 
    value: "my-durable"
  - name: queueGroupName
    value: "my-queue"
  - name: startSequence
    value: 1
  - name: startTime # In Unix format
    value: 1630349391
  - name: deliverAll
    value: false
  - name: flowControl
    value: false
  - name: ackWait
    value: 10s
  - name: maxDeliver
    value: 5
  - name: backOff
    value: "50ms, 1s, 10s"
  - name: maxAckPending
    value: 5000
  - name: replicas
    value: 1
  - name: memoryStorage
    value: false
  - name: rateLimit
    value: 1024
  - name: hearbeat
    value: 15s
  - name: ackPolicy
    value: explicit

Spec metadata fields

Field	Required	Details	Example
natsURL	Y	NATS server address URL	"nats://localhost:4222"
jwt	N	NATS decentralized authentication JWT	"eyJhbGciOiJ...6yJV_adQssw5c"
seedKey	N	NATS decentralized authentication seed key	"SUACS34K232O...5Z3POU7BNIL4Y"
tls_client_cert	N	NATS TLS Client Authentication Certificate	"/path/to/tls.crt"
tls_client_key	N	NATS TLS Client Authentication Key	"/path/to/tls.key"
token	N	NATS token based authentication	"my-token"
name	N	NATS connection name	"my-conn-name"
streamName	N	Name of the JetStream Stream to bind to	"my-stream"
durableName	N	Durable name	"my-durable"
queueGroupName	N	Queue group name	"my-queue"
startSequence	N	Start Sequence	1
startTime	N	Start Time in Unix format	1630349391
deliverAll	N	Set deliver all as Replay Policy	true
flowControl	N	Flow Control	true
ackWait	N	Ack Wait	10s
maxDeliver	N	Max Deliver	15
backOff	N	BackOff	"50ms, 1s, 5s, 10s"
maxAckPending	N	Max Ack Pending	5000
replicas	N	Replicas	3
memoryStorage	N	Memory Storage	false
rateLimit	N	Rate Limit	1024
hearbeat	N	Hearbeat	10s
ackPolicy	N	Ack Policy	explicit

Create a NATS server

{{< tabs "Self-Hosted" "Kubernetes">}}

{{% codetab %}} You can run a NATS Server with JetStream enabled locally using Docker:

docker run -d -p 4222:4222 nats:latest -js

You can then interact with the server using the client port: localhost:4222. {{% /codetab %}}

{{% codetab %}} Install NATS JetStream on Kubernetes by using the helm:

helm repo add nats https://nats-io.github.io/k8s/helm/charts/
helm install --set nats.jetstream.enabled=true my-nats nats/nats

This installs a single NATS server into the default namespace. To interact with NATS, find the service with:

kubectl get svc my-nats

For more information on helm chart settings, see the Helm chart documentation.

{{% /codetab %}}

{{< /tabs >}}

Create JetStream

It is essential to create a NATS JetStream for a specific subject. For example, for a NATS server running locally use:

nats -s localhost:4222 stream add myStream --subjects mySubject

Related links

• [Basic schema for a Dapr component]({{< ref component-schema >}})
• Read [this guide]({{< ref "howto-publish-subscribe.md#step-2-publish-a-topic" >}}) for instructions on configuring pub/sub components
• [Pub/Sub building block]({{< ref pubsub >}})
• JetStream Documentation
• NATS CLI