PURISTA API / Modules / @purista/dapr-sdk / DaprEventBridge

Class: DaprEventBridge

@purista/dapr-sdk.DaprEventBridge

The DaprEventBridge connects to the Dapr sidecar container. It provides endpoints for invoking commands, triggering subscriptions and emitting event messages. The sidecar container invokes commands and subscriptions of the service connected to the event bridge. A DaprClient (http fetch) is used for communication from the service/event bridge to the sidecar container.

Names for services, commands, subscriptions and events are converted to kebab-case. If the event bridge is configured to expose REST endpoints defined in command builder, the endpoints are generated as defined in the command builder.

The event bridge is using Hono under the hood. You need to provide a serve function. Depending on your runtime (Node, Bun, Deno) an adapter might be needed.

See

Hono website

Example

import { DaprConfigStore, DaprEventBridge, DaprSecretStore, DaprStateStore } from '@purista/dapr-sdk'

const eventBridge = new DaprEventBridge({
   serve,
 })

// start the services first ...

await eventBridge.start()

Hierarchy

• HttpEventBridge<DaprEventBridgeConfig>

  ↳ DaprEventBridge

Implements

• EventBridge

Table of contents

Constructors

• constructor

Properties

• app
• client
• config
• defaultCommandTimeout
• instanceId
• isShuttingDown
• isStarted
• logger
• name
• pubSubSubscriptions
• server
• traceProvider

Methods

• destroy
• emit
• emitMessage
• getTracer
• invoke
• isHealthy
• isReady
• off
• on
• registerCommand
• registerSubscription
• removeAllListeners
• start
• startActiveSpan
• unregisterCommand
• unregisterSubscription
• wrapInSpan

Constructors

constructor

• new DaprEventBridge(config): DaprEventBridge

Parameters

Name	Type	Description
config	Object	-
config.apiPrefix?	string	the prefix to be used if the command is configured as REST api endpoint according to the OpenAPI defintion needs to enableRestApiExpose set to true Default ts /api
config.clientConfig?	DaprClientConfig	-
config.commandPayloadAsCloudEvent?	boolean	command invocations are wrapped in CloudEvent Link https://github.com/cloudevents/spec/tree/v1.0 Default ts false
config.defaultCommandTimeout?	number	Overwrite the hardcoded default timeout of command invocations
config.enableHttpCompression?	boolean	enable HTTP compression in web server Default ts true
config.enableRestApiExpose?	boolean	expose commands as regular REST endpoints when they are configured as endpoints Default ts true
config.instanceId?	string	The instance id of the event bridge. If not set, a id will generated each time a instance is created. Use this if there is a need to always have the same instance id.
config.logLevel?	LogLevelName	If no logger instance is given, use this log level
config.logger?	Logger	A logger instance
config.name?	string	name of the bridge Default ts HttpEventBridge
config.pathPrefix?	string	the prefix to be used for exposing commands as endpoints expecting a event bus message Default ts purista
config.serve	(options: { fetch: (request: Request) => unknown ; hostname?: string ; port?: number }) => Server<typeof IncomingMessage, typeof ServerResponse> | Http2Server | Http2SecureServer	The serve function is depending on the runtime. - Bun: Bun.serve - Node.js: serve function from additional package @hono/hono-node-server - Deno: serve function from package https://deno.land/std/http/server.ts See https://hono.dev
config.serverHost?	string	Host of the server. Default ts 127.0.0.1
config.serverPort?	number	Port of the server. Default ts 8080
config.spanProcessor?	SpanProcessor	A OpenTelemetry span processor
config.subscriptionPayloadAsCloudEvent?	boolean	subscription invocations are wrapped in CloudEvent Link https://github.com/cloudevents/spec/tree/v1.0 Default ts false

Returns

DaprEventBridge

Overrides

HttpEventBridge.constructor

Defined in

dapr-sdk/src/DaprEventBridge/DaprEventBridge.impl.ts:45

Properties

app

• app: Hono<Env, BlankSchema, "/">

Inherited from

HttpEventBridge.app

Defined in

base-http-bridge/dist/commonjs/HttpEventBridge/HttpEventBridge.impl.d.ts:26

---

client

• client: HttpEventBridgeClient

Inherited from

HttpEventBridge.client

Defined in

base-http-bridge/dist/commonjs/HttpEventBridge/HttpEventBridge.impl.d.ts:29

---

config

• config: Complete<{ apiPrefix?: string ; clientConfig?: DaprClientConfig ; commandPayloadAsCloudEvent?: boolean ; defaultCommandTimeout?: number ; enableHttpCompression?: boolean ; enableRestApiExpose?: boolean ; instanceId?: string ; logLevel?: LogLevelName ; logger?: Logger ; name?: string ; pathPrefix?: string ; serve: (options: { fetch: (request: Request) => unknown ; hostname?: string ; port?: number }) => Server<typeof IncomingMessage, typeof ServerResponse> | Http2Server | Http2SecureServer ; serverHost?: string ; serverPort?: number ; spanProcessor?: SpanProcessor ; subscriptionPayloadAsCloudEvent?: boolean }>

Inherited from

HttpEventBridge.config

Defined in

core/dist/commonjs/core/EventBridge/EventBridgeBaseClass.impl.d.ts:14

---

defaultCommandTimeout

• defaultCommandTimeout: number

The default time until when a command invocation automatically returns a time out error

Implementation of

EventBridge.defaultCommandTimeout

Inherited from

HttpEventBridge.defaultCommandTimeout

Defined in

core/dist/commonjs/core/EventBridge/EventBridgeBaseClass.impl.d.ts:17

---

instanceId

• instanceId: string

Implementation of

EventBridge.instanceId

Inherited from

HttpEventBridge.instanceId

Defined in

core/dist/commonjs/core/EventBridge/EventBridgeBaseClass.impl.d.ts:16

---

isShuttingDown

• isShuttingDown: boolean

Inherited from

HttpEventBridge.isShuttingDown

Defined in

base-http-bridge/dist/commonjs/HttpEventBridge/HttpEventBridge.impl.d.ts:27

---

isStarted

• isStarted: boolean

Inherited from

HttpEventBridge.isStarted

Defined in

base-http-bridge/dist/commonjs/HttpEventBridge/HttpEventBridge.impl.d.ts:28

---

logger

• logger: Logger

Inherited from

HttpEventBridge.logger

Defined in

core/dist/commonjs/core/EventBridge/EventBridgeBaseClass.impl.d.ts:12

---

name

• name: string

Implementation of

EventBridge.name

Inherited from

HttpEventBridge.name

Defined in

core/dist/commonjs/core/EventBridge/EventBridgeBaseClass.impl.d.ts:15

---

pubSubSubscriptions

• Private pubSubSubscriptions: DaprPubSubType[] = []

Defined in

dapr-sdk/src/DaprEventBridge/DaprEventBridge.impl.ts:43

---

server

• server: undefined | Server<typeof IncomingMessage, typeof ServerResponse> | Http2Server | Http2SecureServer

Inherited from

HttpEventBridge.server

Defined in

base-http-bridge/dist/commonjs/HttpEventBridge/HttpEventBridge.impl.d.ts:25

---

traceProvider

• traceProvider: NodeTracerProvider

Inherited from

HttpEventBridge.traceProvider

Defined in

core/dist/commonjs/core/EventBridge/EventBridgeBaseClass.impl.d.ts:13

Methods

destroy

▸ destroy(): Promise<void>

Shut down event bridge as gracefully as possible

Returns

Promise<void>

Implementation of

EventBridge.destroy

Inherited from

HttpEventBridge.destroy

Defined in

base-http-bridge/dist/commonjs/HttpEventBridge/HttpEventBridge.impl.d.ts:43

---

emit

▸ emit<K>(eventName, parameter?): void

Type parameters

Name	Type
K	extends EventKey<{ eventbridge-connected: never ; eventbridge-connection-error: unknown ; eventbridge-disconnected: never ; eventbridge-error: unknown ; eventbridge-reconnecting: never }>

Parameters

Name	Type
eventName	K
parameter?	{ eventbridge-connected: never ; eventbridge-connection-error: unknown ; eventbridge-disconnected: never ; eventbridge-error: unknown ; eventbridge-reconnecting: never }[K]

Returns

void

Inherited from

HttpEventBridge.emit

Defined in

core/dist/commonjs/core/types/GenericEventEmitter.d.ts:13

---

emitMessage

▸ emitMessage<T>(message): Promise<Readonly<EBMessage>>

Emit a message to the eventbridge without awaiting a result

Type parameters

Name	Type
T	extends EBMessage

Parameters

Name	Type	Description
message	Omit<EBMessage, "id" | "timestamp" | "correlationId">	the message

Returns

Promise<Readonly<EBMessage>>

Implementation of

EventBridge.emitMessage

Inherited from

HttpEventBridge.emitMessage

Defined in

base-http-bridge/dist/commonjs/HttpEventBridge/HttpEventBridge.impl.d.ts:32

---

getTracer

▸ getTracer(): Tracer

Returns open telemetry tracer of this service

Returns

Tracer

Tracer

Inherited from

HttpEventBridge.getTracer

Defined in

core/dist/commonjs/core/EventBridge/EventBridgeBaseClass.impl.d.ts:24

---

invoke

▸ invoke<T>(input, ttl?): Promise<T>

Call a command of a service and return the result of this command

Type parameters

Name
T

Parameters

Name	Type	Description
input	Omit<{ contentEncoding: string ; contentType: string ; correlationId: string ; eventName?: string ; id: string ; messageType: Command ; otp?: string ; payload: { parameter: unknown ; payload: unknown } ; principalId?: string ; receiver: EBMessageAddress ; sender: { instanceId: string ; serviceName: string ; serviceTarget: string ; serviceVersion: string } ; tenantId?: string ; timestamp: number ; traceId?: string }, "id" | "timestamp" | "correlationId" | "messageType">	a partial command message
ttl?	number	the time to live (timeout) of the invocation

Returns

Promise<T>

Implementation of

EventBridge.invoke

Inherited from

HttpEventBridge.invoke

Defined in

base-http-bridge/dist/commonjs/HttpEventBridge/HttpEventBridge.impl.d.ts:33

---

isHealthy

▸ isHealthy(): Promise<boolean>

Indicates if the eventbridge is running and works correctly

Returns

Promise<boolean>

Implementation of

EventBridge.isHealthy

Inherited from

HttpEventBridge.isHealthy

Defined in

base-http-bridge/dist/commonjs/HttpEventBridge/HttpEventBridge.impl.d.ts:39

---

isReady

▸ isReady(): Promise<boolean>

Indicates if the eventbridge has been started and is connected to underlaying message broker

Returns

Promise<boolean>

Implementation of

EventBridge.isReady

Inherited from

HttpEventBridge.isReady

Defined in

base-http-bridge/dist/commonjs/HttpEventBridge/HttpEventBridge.impl.d.ts:38

---

off

▸ off<K>(eventName, fn): void

Type parameters

Name	Type
K	extends EventKey<{ eventbridge-connected: never ; eventbridge-connection-error: unknown ; eventbridge-disconnected: never ; eventbridge-error: unknown ; eventbridge-reconnecting: never }>

Parameters

Name	Type
eventName	K
fn	EventReceiver<{ eventbridge-connected: never ; eventbridge-connection-error: unknown ; eventbridge-disconnected: never ; eventbridge-error: unknown ; eventbridge-reconnecting: never }[K]>

Returns

void

Inherited from

HttpEventBridge.off

Defined in

core/dist/commonjs/core/types/GenericEventEmitter.d.ts:12

---

on

▸ on<K>(eventName, fn): void

Type parameters

Name	Type
K	extends EventKey<{ eventbridge-connected: never ; eventbridge-connection-error: unknown ; eventbridge-disconnected: never ; eventbridge-error: unknown ; eventbridge-reconnecting: never }>

Parameters

Name	Type
eventName	K
fn	EventReceiver<{ eventbridge-connected: never ; eventbridge-connection-error: unknown ; eventbridge-disconnected: never ; eventbridge-error: unknown ; eventbridge-reconnecting: never }[K]>

Returns

void

Inherited from

HttpEventBridge.on

Defined in

core/dist/commonjs/core/types/GenericEventEmitter.d.ts:11

---

registerCommand

▸ registerCommand(address, cb, metadata, eventBridgeConfig): Promise<string>

Parameters

Name	Type
address	EBMessageAddress
cb	(message: { contentEncoding: string ; contentType: string ; correlationId: string ; eventName?: string ; id: string ; messageType: Command ; otp?: string ; payload: { parameter: unknown ; payload: unknown } ; principalId?: string ; receiver: EBMessageAddress ; sender: { instanceId: string ; serviceName: string ; serviceTarget: string ; serviceVersion: string } ; tenantId?: string ; timestamp: number ; traceId?: string }) => Promise<Readonly<Omit<{ contentEncoding: string ; contentType: string ; correlationId: string ; eventName?: string ; id: string ; messageType: CommandSuccessResponse ; otp?: string ; payload: unknown ; principalId?: string ; receiver: { instanceId: string ; serviceName: string ; serviceTarget: string ; serviceVersion: string } ; sender: { instanceId: string ; serviceName: string ; serviceTarget: string ; serviceVersion: string } ; tenantId?: string ; timestamp: number ; traceId?: string }, "instanceId">> | Readonly<Omit<{ contentEncoding: "utf-8" ; contentType: "application/json" ; correlationId: string ; eventName?: string ; id: string ; isHandledError: boolean ; messageType: CommandErrorResponse ; otp?: string ; payload: { data?: unknown ; message: string ; status: StatusCode } ; principalId?: string ; receiver: { instanceId: string ; serviceName: string ; serviceTarget: string ; serviceVersion: string } ; sender: { instanceId: string ; serviceName: string ; serviceTarget: string ; serviceVersion: string } ; tenantId?: string ; timestamp: number ; traceId?: string }, "instanceId">>>
metadata	Object
metadata.expose	{ contentEncodingRequest?: string ; contentEncodingResponse?: string ; contentTypeRequest?: string ; contentTypeResponse?: string ; deprecated?: boolean ; inputPayload?: SchemaObject ; outputPayload?: SchemaObject ; parameter?: SchemaObject } & { http: { method: "POST" | "GET" | "PATCH" | "PUT" | "DELETE" ; openApi?: { additionalStatusCodes?: StatusCode[] ; description: string ; isSecure: boolean ; operationId?: string ; query?: QueryParameter<{}>[] ; summary: string ; tags?: string[] } ; path: string } }
eventBridgeConfig	DefinitionEventBridgeConfig

Returns

Promise<string>

Implementation of

EventBridge.registerCommand

Inherited from

HttpEventBridge.registerCommand

Defined in

base-http-bridge/dist/commonjs/HttpEventBridge/HttpEventBridge.impl.d.ts:34

---

registerSubscription

▸ registerSubscription(subscription, cb): Promise<string>

Register a new subscription

Parameters

Name	Type	Description
subscription	Subscription	the subscription definition
cb	(message: EBMessage) => Promise<undefined | Omit<{ contentEncoding: string ; contentType: string ; correlationId?: string ; eventName: string ; id: string ; messageType: CustomMessage ; otp?: string ; payload?: unknown ; principalId?: string ; receiver?: EBMessageAddress ; sender: { instanceId: string ; serviceName: string ; serviceTarget: string ; serviceVersion: string } ; tenantId?: string ; timestamp: number ; traceId?: string }, "id" | "timestamp">>	the function to be called if a matching message arrives

Returns

Promise<string>

Implementation of

EventBridge.registerSubscription

Overrides

HttpEventBridge.registerSubscription

Defined in

dapr-sdk/src/DaprEventBridge/DaprEventBridge.impl.ts:97

---

removeAllListeners

▸ removeAllListeners(): void

Returns

void

Inherited from

HttpEventBridge.removeAllListeners

Defined in

core/dist/commonjs/core/types/GenericEventEmitter.d.ts:14

---

start

▸ start(): Promise<void>

Start the eventbridge and connect to the underlaying message broker

Returns

Promise<void>

Implementation of

EventBridge.start

Overrides

HttpEventBridge.start

Defined in

dapr-sdk/src/DaprEventBridge/DaprEventBridge.impl.ts:80

---

startActiveSpan

▸ startActiveSpan<F>(name, opts, context, fn): Promise<F>

Start a child span for opentelemetry tracking

Type parameters

Name
F

Parameters

Name	Type	Description
name	string	name of span
opts	SpanOptions	span options
context	undefined | Context	optional context
fn	(span: Span) => Promise<F>	function to be executed within the span

Returns

Promise<F>

return value of fn

Inherited from

HttpEventBridge.startActiveSpan

Defined in

core/dist/commonjs/core/EventBridge/EventBridgeBaseClass.impl.d.ts:33

---

unregisterCommand

▸ unregisterCommand(address): Promise<void>

Unregister a service command

Parameters

Name	Type	Description
address	EBMessageAddress	The address (service name, version and command name) of the command to be de-registered

Returns

Promise<void>

Implementation of

EventBridge.unregisterCommand

Inherited from

HttpEventBridge.unregisterCommand

Defined in

base-http-bridge/dist/commonjs/HttpEventBridge/HttpEventBridge.impl.d.ts:35

---

unregisterSubscription

▸ unregisterSubscription(address): Promise<void>

Parameters

Name	Type
address	EBMessageAddress

Returns

Promise<void>

Implementation of

EventBridge.unregisterSubscription

Inherited from

HttpEventBridge.unregisterSubscription

Defined in

base-http-bridge/dist/commonjs/HttpEventBridge/HttpEventBridge.impl.d.ts:37

---

wrapInSpan

▸ wrapInSpan<F>(name, opts, fn, context?): Promise<F>

Start span for opentelemetry tracking on same level. The created span will not become the "active" span within opentelemetry!

This means during logging and similar the spanId of parent span is logged.

Use wrapInSpan for marking points in flow of one bigger function, but not to trace the program flow itself

Type parameters

Name
F

Parameters

Name	Type	Description
name	string	name of span
opts	SpanOptions	span options
fn	(span: Span) => Promise<F>	function te be executed in the span
context?	Context	span context

Returns

Promise<F>

return value of fn

Inherited from

HttpEventBridge.wrapInSpan

Defined in

core/dist/commonjs/core/EventBridge/EventBridgeBaseClass.impl.d.ts:49