Share via

Publier des événements dans des rubriques d’espace de noms à l’aide de Java

  • Article

Cet article fournit un guide pas à pas rapide pour publier CloudEvents à l’aide de Java. L’exemple de code de cet article utilise le format JSON CloudEvents lors de l’envoi d’événements.

Prérequis

Les conditions préalables que vous devez avoir en place avant de continuer sont les suivantes :

  • Un espace de noms, une rubrique et un abonnement aux événements.

  • Le dernier package du kit de développement logiciel (SDK) en bêta. Si vous utilisez maven, vous pouvez consulter le référentiel central maven.

    Important

    La prise en charge du kit de développement logiciel (SDK) du plan de données de livraison par tirage (pull) est disponible dans les packages bêta. Vous devez utiliser le dernier package bêta dans votre projet.

  • Un environnement de développement intégré (IDE, integrated development environment) qui prend en charge Java, comme IntelliJ IDEA, Eclipse IDE ou Visual Studio Code.

  • Java JRE exécutant le niveau de langage Java 8.

Publier des événements dans une rubrique d’espace de noms

Utilisez la classe suivante pour comprendre les étapes de base pour publier des événements.

package com.azure.messaging.eventgrid.samples;

import com.azure.core.credential.AzureKeyCredential;
import com.azure.core.http.HttpClient;
import com.azure.core.models.CloudEvent;
import com.azure.core.models.CloudEventDataFormat;
import com.azure.core.util.BinaryData;
import com.azure.messaging.eventgrid.EventGridClient;
import com.azure.messaging.eventgrid.EventGridClientBuilder;
import com.azure.messaging.eventgrid.EventGridMessagingServiceVersion;

import java.time.OffsetDateTime;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Random;

/**
 * <p>Simple demo publisher of CloudEvents to Event Grid namespace topics.
 *
 * This code samples should use Java 1.8 level or above to avoid compilation errors.
 *
 * You should consult the resources below to use the client SDK and set up your project using maven.
 * @see <a href="https://github.com/Azure/azure-sdk-for-java/tree/main/sdk/eventgrid/azure-messaging-eventgrid">Event Grid data plane client SDK documentation</a>
 * @see <a href="https://github.com/Azure/azure-sdk-for-java/blob/main/sdk/boms/azure-sdk-bom/README.md">Azure BOM for client libraries</a>
 * @see <a href="https://aka.ms/spring/versions">Spring Version Mapping</a> if you are using Spring.
 * @see <a href="https://aka.ms/azsdk">Tool with links to control plane and data plane SDKs across all languages supported</a>.
 *</p>
 */
public class NamespaceTopicPublisher {
    private static final String TOPIC_NAME = "<yourNamespaceTopicName>";
    public static final String ENDPOINT =  "<yourFullHttpsUrlToTheNamespaceEndpoint>";
    public static final int NUMBER_OF_EVENTS_TO_BUILD_THAT_DOES_NOT_EXCEED_100 = 10;

    //TODO  Do NOT include keys in source code. This code's objective is to give you a succinct sample about using Event Grid, not to provide an authoritative example for handling secrets in applications.
    /**
    *  For security concerns, you should not have keys or any other secret in any part of the application code.
     *  You should use services like Azure Key Vault for managing your keys.
     */
    public static final AzureKeyCredential CREDENTIAL = new AzureKeyCredential("<namespace key>");

    public static void main(String[] args) {
        //TODO Update Event Grid version number to your desired version. You can find more information on data plane APIs here:
        //https://learn.microsoft.com/en-us/rest/api/eventgrid/.
        EventGridClient eventGridClient = new EventGridClientBuilder()
                .httpClient(HttpClient.createDefault())  // Requires Java 1.8 level
                .endpoint(ENDPOINT)
                .serviceVersion(EventGridMessagingServiceVersion.V2023_06_01_PREVIEW)
                .credential(CREDENTIAL).buildClient();   // you may want to use .buildAsyncClient() for an asynchronous (project reactor) client.

        List<CloudEvent> cloudEvents = buildCloudEvents(NUMBER_OF_EVENTS_TO_BUILD_THAT_DOES_NOT_EXCEED_100);

        eventGridClient.publishCloudEvents(TOPIC_NAME, cloudEvents);

        System.out.println("--> Number of events published: " + NUMBER_OF_EVENTS_TO_BUILD_THAT_DOES_NOT_EXCEED_100); // There is no partial publish. Either all succeed or none.
    }

    /**
     * <p>Builds a list of valid CloudEvents for testing purposes</p>
     * @param numberOfEventsToBuild this should not exceed 100, which is the maximum number of events allowed in a single HTTP request or 1MB in size, whichever is met first.
     * @return the list of CloudEvents
     */
    private static List<CloudEvent> buildCloudEvents(int numberOfEventsToBuild) {
        List<CloudEvent> cloudEvents = new ArrayList<>(numberOfEventsToBuild);
        while (numberOfEventsToBuild >= 1) {
            cloudEvents.add(buildCloudEvent());
            numberOfEventsToBuild--;
        }
        return cloudEvents;
    }

    /**
     * <p>Builds a valid CloudEvent for testing purposes.</p>
     * @return a CloudEvent
     */
    private static CloudEvent buildCloudEvent() {
        String orderId = Integer.toString(new Random().nextInt(1000-10+1) + 10);  // Generates a random integer between 1000 and 1 (exclusive)

        return new CloudEvent("/account/a-4305/orders", "com.MyCompanyName.OrderCreated",
                BinaryData.fromObject(new HashMap<String, String>() {
                    {
                        put("orderId", orderId);
                        put("orderResourceURL", "https://www.MyCompanyName.com/orders/" + orderId);
                        put("isRushOrder", "true");
                        put("customerType", "Institutional");
                    }
                }), CloudEventDataFormat.JSON, "application/json")
                .setTime(OffsetDateTime.now());
    }
}

Étapes suivantes