SDK do Azure Event Hubs para TypeScript

Streaming de eventos de alta vazão e ingestão de dados em tempo real.

Instalação

npm install @azure/event-hubs @azure/identity

Para checkpointing com grupos de consumidores:

npm install @azure/eventhubs-checkpointstore-blob @azure/storage-blob

Variáveis de Ambiente

EVENTHUB_NAMESPACE=<namespace>.servicebus.windows.net
EVENTHUB_NAME=my-eventhub
STORAGE_ACCOUNT_NAME=<storage-account>
STORAGE_CONTAINER_NAME=checkpoints

Autenticação

import { EventHubProducerClient, EventHubConsumerClient } from "@azure/event-hubs";
import { DefaultAzureCredential } from "@azure/identity";

const fullyQualifiedNamespace = process.env.EVENTHUB_NAMESPACE!;
const eventHubName = process.env.EVENTHUB_NAME!;
const credential = new DefaultAzureCredential();

// Producer
const producer = new EventHubProducerClient(fullyQualifiedNamespace, eventHubName, credential);

// Consumer
const consumer = new EventHubConsumerClient(
  "$Default", // Consumer group
  fullyQualifiedNamespace,
  eventHubName,
  credential
);

Fluxo de Trabalho Principal

Enviar Eventos

const producer = new EventHubProducerClient(namespace, eventHubName, credential);

// Create batch and add events
const batch = await producer.createBatch();
batch.tryAdd({ body: { temperature: 72.5, deviceId: "sensor-1" } });
batch.tryAdd({ body: { temperature: 68.2, deviceId: "sensor-2" } });

await producer.sendBatch(batch);
await producer.close();

Enviar para Partição Específica

// By partition ID
const batch = await producer.createBatch({ partitionId: "0" });

// By partition key (consistent hashing)
const batch = await producer.createBatch({ partitionKey: "device-123" });

Receber Eventos (Simples)

const consumer = new EventHubConsumerClient("$Default", namespace, eventHubName, credential);

const subscription = consumer.subscribe({
  processEvents: async (events, context) => {
    for (const event of events) {
      console.log(`Partition: ${context.partitionId}, Body: ${JSON.stringify(event.body)}`);
    }
  },
  processError: async (err, context) => {
    console.error(`Error on partition ${context.partitionId}: ${err.message}`);
  },
});

// Stop after some time
setTimeout(async () => {
  await subscription.close();
  await consumer.close();
}, 60000);

Receber com Checkpointing (Produção)

import { EventHubConsumerClient } from "@azure/event-hubs";
import { ContainerClient } from "@azure/storage-blob";
import { BlobCheckpointStore } from "@azure/eventhubs-checkpointstore-blob";

const containerClient = new ContainerClient(
  `https://${storageAccount}.blob.core.windows.net/${containerName}`,
  credential
);

const checkpointStore = new BlobCheckpointStore(containerClient);

const consumer = new EventHubConsumerClient(
  "$Default",
  namespace,
  eventHubName,
  credential,
  checkpointStore
);

const subscription = consumer.subscribe({
  processEvents: async (events, context) => {
    for (const event of events) {
      console.log(`Processing: ${JSON.stringify(event.body)}`);
    }
    // Checkpoint after processing batch
    if (events.length > 0) {
      await context.updateCheckpoint(events[events.length - 1]);
    }
  },
  processError: async (err, context) => {
    console.error(`Error: ${err.message}`);
  },
});

Receber de Posição Específica

const subscription = consumer.subscribe({
  processEvents: async (events, context) => { /* ... */ },
  processError: async (err, context) => { /* ... */ },
}, {
  startPosition: {
    // Start from beginning
    "0": { offset: "@earliest" },
    // Start from end (new events only)
    "1": { offset: "@latest" },
    // Start from specific offset
    "2": { offset: "12345" },
    // Start from specific time
    "3": { enqueuedOn: new Date("2024-01-01") },
  },
});

Propriedades do Event Hub

// Get hub info
const hubProperties = await producer.getEventHubProperties();
console.log(`Partitions: ${hubProperties.partitionIds}`);

// Get partition info
const partitionProperties = await producer.getPartitionProperties("0");
console.log(`Last sequence: ${partitionProperties.lastEnqueuedSequenceNumber}`);

Opções de Processamento em Lote

const subscription = consumer.subscribe(
  {
    processEvents: async (events, context) => { /* ... */ },
    processError: async (err, context) => { /* ... */ },
  },
  {

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