List Lite topics

List Lite topics in a project.

Documentation pages that include this code sample

To view the code sample used in context, see the following documentation:

Code sample

Java

import com.google.cloud.pubsublite.AdminClient;
import com.google.cloud.pubsublite.AdminClientSettings;
import com.google.cloud.pubsublite.CloudRegion;
import com.google.cloud.pubsublite.CloudZone;
import com.google.cloud.pubsublite.LocationPath;
import com.google.cloud.pubsublite.ProjectNumber;
import com.google.cloud.pubsublite.proto.Topic;
import java.util.List;

public class ListTopicsExample {

  public static void main(String... args) throws Exception {
    // TODO(developer): Replace these variables before running the sample.
    String cloudRegion = "your-cloud-region";
    char zoneId = 'b';
    long projectNumber = Long.parseLong("123456789");

    listTopicsExample(cloudRegion, zoneId, projectNumber);
  }

  public static void listTopicsExample(String cloudRegion, char zoneId, long projectNumber)
      throws Exception {

    AdminClientSettings adminClientSettings =
        AdminClientSettings.newBuilder().setRegion(CloudRegion.of(cloudRegion)).build();

    LocationPath locationPath =
        LocationPath.newBuilder()
            .setProject(ProjectNumber.of(projectNumber))
            .setLocation(CloudZone.of(CloudRegion.of(cloudRegion), zoneId))
            .build();

    try (AdminClient adminClient = AdminClient.create(adminClientSettings)) {
      List<Topic> topics = adminClient.listTopics(locationPath).get();
      for (Topic topic : topics) {
        System.out.println(topic.getAllFields());
      }
      System.out.println(topics.size() + " topic(s) listed.");
    }
  }
}

Python

from google.cloud.pubsublite import AdminClient
from google.cloud.pubsublite.types import CloudRegion, CloudZone, LocationPath

# TODO(developer):
# project_number = 1122334455
# cloud_region = "us-central1"
# zone_id = "a"

cloud_region = CloudRegion(cloud_region)
location = CloudZone(cloud_region, zone_id)
location_path = LocationPath(project_number, location)

client = AdminClient(cloud_region)
response = client.list_topics(location_path)

for topic in response:
    print(topic)

print(f"{len(response)} topic(s) listed in your project and location.")