azure-eventgrid-java

Author's original introduction

Build event-driven applications with Azure Event Grid SDK for Java. Use when publishing events, implementing pub/sub patterns, or integrating with Azure services via events.

SkillPi interpretation

Tasks

azure-eventgrid-java

Audience

Use the scope in the original author introduction.

Inputs and outputs

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Software, accounts and paid services

This azure-eventgrid-java package contains Microsoft Azure SDK documentation and examples, not a runtime-verified installer. Check SDK names/versions, tenant/subscription and actual endpoints; grant only task-specific least privilege. Never put administrator credentials or real secrets in samples, logs or commits. Connected cloud services may receive selected text, documents, audio, messages, logs or other input and incur charges; confirm scope, redaction and costs first. Ask the user to confirm each resource creation/update/deletion, key/access change or outbound message and test with disposable resources before production. Replace and verify placeholder endpoints and samples. SkillPi checked pinned source, complete attachments and static/antivirus evidence only; it did not run the SDK, verify service compatibility or authorize cloud access.

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Original author introduction preserved; Chinese is a corresponding translation. Examples were not run by SkillPi; versions, compatibility and outcomes are author claims.

Testing

Not tested

Security rating and access scope

caution · Static evidence review; not a runtime safety guarantee.

This azure-eventgrid-java package contains Microsoft Azure SDK documentation and examples, not a runtime-verified installer. Check SDK names/versions, tenant/subscription and actual endpoints; grant only task-specific least privilege. Never put administrator credentials or real secrets in samples, logs or commits. Connected cloud services may receive selected text, documents, audio, messages, logs or other input and incur charges; confirm scope, redaction and costs first. Ask the user to confirm each resource creation/update/deletion, key/access change or outbound message and test with disposable resources before production. Replace and verify placeholder endpoints and samples. SkillPi checked pinned source, complete attachments and static/antivirus evidence only; it did not run the SDK, verify service compatibility or authorize cloud access.

Before use, confirm and authorize actual file access, external services and network destinations in your host. This review grants no runtime permissions.

Original SKILL.md

---
name: azure-eventgrid-java
description: Build event-driven applications with Azure Event Grid SDK for Java. Use when publishing events, implementing pub/sub patterns, or integrating with Azure services via events.
license: MIT
metadata:
  author: Microsoft
  version: "1.0.0"
  package: com.azure:azure-messaging-eventgrid
---

# Azure Event Grid SDK for Java

Build event-driven applications using the Azure Event Grid SDK for Java.

## Installation

```xml
<dependency>
    <groupId>com.azure</groupId>
    <artifactId>azure-messaging-eventgrid</artifactId>
    <version>4.27.0</version>
</dependency>
```

## Client Creation

### EventGridPublisherClient

```java
import com.azure.messaging.eventgrid.EventGridPublisherClient;
import com.azure.messaging.eventgrid.EventGridPublisherClientBuilder;
import com.azure.core.credential.AzureKeyCredential;

// With API Key
EventGridPublisherClient<EventGridEvent> client = new EventGridPublisherClientBuilder()
    .endpoint("<topic-endpoint>")
    .credential(new AzureKeyCredential("<access-key>"))
    .buildEventGridEventPublisherClient();

// For CloudEvents
EventGridPublisherClient<CloudEvent> cloudClient = new EventGridPublisherClientBuilder()
    .endpoint("<topic-endpoint>")
    .credential(new AzureKeyCredential("<access-key>"))
    .buildCloudEventPublisherClient();
```

### With DefaultAzureCredential

```java
import com.azure.core.credential.TokenCredential;
import com.azure.identity.AzureIdentityEnvVars;
import com.azure.identity.DefaultAzureCredentialBuilder;
import com.azure.identity.ManagedIdentityCredentialBuilder;

// Local dev: DefaultAzureCredential. Production: set AZURE_TOKEN_CREDENTIALS=prod or AZURE_TOKEN_CREDENTIALS=<specific_credential>
TokenCredential credential = new DefaultAzureCredentialBuilder()
    .requireEnvVars(AzureIdentityEnvVars.AZURE_TOKEN_CREDENTIALS)
    .build();
// Or use a specific credential directly in production:
// See https://learn.microsoft.com/java/api/overview/azure/identity-readme?view=azure-java-stable#credential-classes
// TokenCredential credential = new ManagedIdentityCredentialBuilder().build();

EventGridPublisherClient<EventGridEvent> client = new EventGridPublisherClientBuilder()
    .endpoint("<topic-endpoint>")
    .credential(credential)
    .buildEventGridEventPublisherClient();
```

### Async Client

```java
import com.azure.messaging.eventgrid.EventGridPublisherAsyncClient;

EventGridPublisherAsyncClient<EventGridEvent> asyncClient = new EventGridPublisherClientBuilder()
    .endpoint("<topic-endpoint>")
    .credential(new AzureKeyCredential("<access-key>"))
    .buildEventGridEventPublisherAsyncClient();
```

## Event Types

| Type | Description |
|------|-------------|
| `EventGridEvent` | Azure Event Grid native schema |
| `CloudEvent` | CNCF CloudEvents 1.0 specification |
| `BinaryData` | Custom schema events |

## Core Patterns

### Publish EventGridEvent

```java
import com.azure.messaging.eventgrid.EventGridEvent;
import com.azure.core.util.BinaryData;

EventGridEvent event = new EventGridEvent(
    "resource/path",           // subject
    "MyApp.Events.OrderCreated", // eventType
    BinaryData.fromObject(new OrderData("order-123", 99.99)), // data
    "1.0"                      // dataVersion
);

client.sendEvent(event);
```

### Publish Multiple Events

```java
List<EventGridEvent> events = Arrays.asList(
    new EventGridEvent("orders/1", "Order.Created", 
        BinaryData.fromObject(order1), "1.0"),
    new EventGridEvent("orders/2", "Order.Created", 
        BinaryData.fromObject(order2), "1.0")
);

client.sendEvents(events);
```

### Publish CloudEvent

```java
import com.azure.core.models.CloudEvent;
import com.azure.core.models.CloudEventDataFormat;

CloudEvent cloudEvent = new CloudEvent(
    "/myapp/orders",           // source
    "order.created",           // type
    BinaryData.fromObject(orderData), // data
    CloudEventDataFormat.JSON  // dataFormat
);
cloudEvent.setSubject("orders/12345");
cloudEvent.setId(UUID.randomUUID().toString());

cloudClient.sendEvent(cloudEvent);
```

### Publish CloudEvents Batch

```java
List<CloudEvent> cloudEvents = Arrays.asList(
    new CloudEvent("/app", "event.type1", BinaryData.fromString("data1"), CloudEventDataFormat.JSON),
    new CloudEvent("/app", "event.type2", BinaryData.fromString("data2"), CloudEventDataFormat.JSON)
);

cloudClient.sendEvents(cloudEvents);
```

### Async Publishing

```java
asyncClient.sendEvent(event)
    .subscribe(
        unused -> System.out.println("Event sent successfully"),
        error -> System.err.println("Error: " + error.getMessage())
    );

// With multiple events
asyncClient.sendEvents(events)
    .doOnSuccess(unused -> System.out.println("All events sent"))
    .doOnError(error -> System.err.println("Failed: " + error))
    .block(); // Block if needed
```

### Custom Event Data Class

```java
public class OrderData {
    private String orderId;
    private double amount;
    private String customerId;
    
    public OrderData(String orderId, double amount) {
        this.orderId = orderId;
        this.amount = amount;
    }
    
    // Getters and setters
}

// Usage
OrderData order = new OrderData("ORD-123", 150.00);
EventGridEvent event = new EventGridEvent(
    "orders/" + order.getOrderId(),
    "MyApp.Order.Created",
    BinaryData.fromObject(order),
    "1.0"
);
```

## Receiving Events

### Parse EventGridEvent

```java
import com.azure.messaging.eventgrid.EventGridEvent;

// From JSON string (e.g., webhook payload)
String jsonPayload = "[{\"id\": \"...\", ...}]";
List<EventGridEvent> events = EventGridEvent.fromString(jsonPayload);

for (EventGridEvent event : events) {
    System.out.println("Event Type: " + event.getEventType());
    System.out.println("Subject: " + event.getSubject());
    System.out.println("Event Time: " + event.getEventTime());
    
    // Get data
    BinaryData data = event.getData();
    OrderData orderData = data.toObject(OrderData.class);
}
```

### Parse CloudEvent

```java
import com.azure.core.models.CloudEvent;

String cloudEventJson = "[{\"specversion\": \"1.0\", ...}]";
List<CloudEvent> cloudEvents = CloudEvent.fromString(cloudEventJson);

for (CloudEvent event : cloudEvents) {
    System.out.println("Type: " + event.getType());
    System.out.println("Source: " + event.getSource());
    System.out.println("ID: " + event.getId());
    
    MyEventData data = event.getData().toObject(MyEventData.class);
}
```

### Handle System Events

```java
import com.azure.messaging.eventgrid.systemevents.*;

for (EventGridEvent event : events) {
    if (event.getEventType().equals("Microsoft.Storage.BlobCreated")) {
        StorageBlobCreatedEventData blobData = 
            event.getData().toObject(StorageBlobCreatedEventData.class);
        System.out.println("Blob URL: " + blobData.getUrl());
    }
}
```

## Event Grid Namespaces (MQTT/Pull)

### Receive from Namespace Topic

```java
import com.azure.messaging.eventgrid.namespaces.EventGridReceiverClient;
import com.azure.messaging.eventgrid.namespaces.EventGridReceiverClientBuilder;
import com.azure.messaging.eventgrid.namespaces.models.*;

EventGridReceiverClient receiverClient = new EventGridReceiverClientBuilder()
    .endpoint("<namespace-endpoint>")
    .credential(new AzureKeyCredential("<key>"))
    .topicName("my-topic")
    .subscriptionName("my-subscription")
    .buildClient();

// Receive events
ReceiveResult result = receiverClient.receive(10, Duration.ofSeconds(30));

for (ReceiveDetails detail : result.getValue()) {
    CloudEvent event = detail.getEvent();
    System.out.println("Event: " + event.getType());
    
    // Acknowledge the event
    receiverClient.acknowledge(Arrays.asList(detail.getBrokerProperties().getLockToken()));
}
```

### Reject or Release Events

```java
// Reject (don't retry)
receiverClient.reject(Arrays.asList(lockToken));

// Release (retry later)
receiverClient.release(Arrays.asList(lockToken));

// Release with delay
receiverClient.release(Arrays.asList(lockToken), 
    new ReleaseOptions().setDelay(ReleaseDelay.BY_60_SECONDS));
```

## Error Handling

```java
import com.azure.core.exception.HttpResponseException;

try {
    client.sendEvent(event);
} catch (HttpResponseException e) {
    System.out.println("Status: " + e.getResponse().getStatusCode());
    System.out.println("Error: " + e.getMessage());
}
```

## Environment Variables

```bash
EVENT_GRID_TOPIC_ENDPOINT=https://<topic-name>.<region>.eventgrid.azure.net/api/events  # Required for all auth methods
EVENT_GRID_ACCESS_KEY=<your-access-key>  # Only required for AzureKeyCredential auth
AZURE_TOKEN_CREDENTIALS=prod  # Required only if DefaultAzureCredential is used in production
```

## Best Practices

1. **Batch Events**: Send multiple events in one call when possible
2. **Idempotency**: Include unique event IDs for deduplication
3. **Schema Validation**: Use strongly-typed event data classes
4. **Retry Logic**: Built-in, but consider dead-letter for failures
5. **Event Size**: Keep events under 1MB (64KB for basic tier)

## Trigger Phrases

- "Event Grid Java"
- "publish events Azure"
- "CloudEvent SDK"
- "event-driven messaging"
- "pub/sub Azure"
- "webhook events"

Copyright and license notice

    MIT License

    Copyright (c) Microsoft Corporation.

    Permission is hereby granted, free of charge, to any person obtaining a copy
    of this software and associated documentation files (the "Software"), to deal
    in the Software without restriction, including without limitation the rights
    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
    copies of the Software, and to permit persons to whom the Software is
    furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice shall be included in all
    copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
    SOFTWARE