SDK Amazon S3: elenco degli oggetti

Mostra un esempio di elenco di oggetti per aiutare gli sviluppatori a risolvere un problema di interoperabilità finché non viene risolto.

Esempio di codice

Go

Per maggiori informazioni, consulta la documentazione di riferimento dell'API Go di Cloud Storage.

Per eseguire l'autenticazione in Cloud Storage, configura Credenziali predefinite dell'applicazione. Per maggiori informazioni, consulta Configurare l'autenticazione per un ambiente di sviluppo locale.

import (
	"context"
	"fmt"
	"io"

	"github.com/aws/aws-sdk-go/aws"
	"github.com/aws/aws-sdk-go/aws/credentials"
	"github.com/aws/aws-sdk-go/aws/session"
	"github.com/aws/aws-sdk-go/service/s3"
)

func listGCSObjects(w io.Writer, bucketName string, googleAccessKeyID string, googleAccessKeySecret string) error {
	// bucketName := "your-gcs-bucket-name"
	// googleAccessKeyID := "Your Google Access Key ID"
	// googleAccessKeySecret := "Your Google Access Key Secret"

	// Create a new client and do the following:
	// 1. Change the endpoint URL to use the Google Cloud Storage XML API endpoint.
	// 2. Use Cloud Storage HMAC Credentials.
	sess := session.Must(session.NewSession(&aws.Config{
		Region:      aws.String("auto"),
		Endpoint:    aws.String("https://storage.googleapis.com"),
		Credentials: credentials.NewStaticCredentials(googleAccessKeyID, googleAccessKeySecret, ""),
	}))

	client := s3.New(sess)
	ctx := context.Background()

	result, err := client.ListObjectsWithContext(ctx, &s3.ListObjectsInput{
		Bucket: aws.String(bucketName),
	})
	if err != nil {
		return fmt.Errorf("ListObjectsWithContext: %w", err)
	}

	fmt.Fprintf(w, "Objects:")
	for _, o := range result.Contents {
		fmt.Fprintf(w, "%s\n", aws.StringValue(o.Key))
	}

	return nil
}

Java

Per maggiori informazioni, consulta la documentazione di riferimento dell'API Java di Cloud Storage.

import com.amazonaws.auth.AWSStaticCredentialsProvider;
import com.amazonaws.auth.BasicAWSCredentials;
import com.amazonaws.client.builder.AwsClientBuilder;
import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.AmazonS3ClientBuilder;
import com.amazonaws.services.s3.model.ObjectListing;
import com.amazonaws.services.s3.model.S3ObjectSummary;

public class ListGcsObjects {
  public static void listGcsObjects(
      String googleAccessKeyId, String googleAccessKeySecret, String bucketName) {

    // String googleAccessKeyId = "your-google-access-key-id";
    // String googleAccessKeySecret = "your-google-access-key-secret";
    // String bucketName = "bucket-name";

    // Create a BasicAWSCredentials using Cloud Storage HMAC credentials.
    BasicAWSCredentials googleCreds =
        new BasicAWSCredentials(googleAccessKeyId, googleAccessKeySecret);

    // Create a new client and do the following:
    // 1. Change the endpoint URL to use the Google Cloud Storage XML API endpoint.
    // 2. Use Cloud Storage HMAC Credentials.
    AmazonS3 interopClient =
        AmazonS3ClientBuilder.standard()
            .withEndpointConfiguration(
                new AwsClientBuilder.EndpointConfiguration(
                    "https://storage.googleapis.com", "auto"))
            .withCredentials(new AWSStaticCredentialsProvider(googleCreds))
            .build();

    // Call GCS to list current objects
    ObjectListing objects = interopClient.listObjects(bucketName);

    // Print objects names
    System.out.println("Objects:");
    for (S3ObjectSummary object : objects.getObjectSummaries()) {
      System.out.println(object.getKey());
    }

    // Explicitly clean up client resources.
    interopClient.shutdown();
  }
}

Python

Per maggiori informazioni, consulta la documentazione di riferimento dell'API Python di Cloud Storage.

import boto3  # type: ignore

def list_gcs_objects(
    google_access_key_id: str, google_access_key_secret: str, bucket_name: str
) -> List[str]:
    """Lists all Cloud Storage objects using AWS SDK for Python (boto3)
    Positional arguments:
        google_access_key_id: hash-based message authentication code (HMAC) access ID
        google_access_key_secret: HMAC access secret
        bucket_name: name of Cloud Storage bucket

    Returned value is a list of strings, one for each object in the bucket.

    To use this sample:
    1. Create a Cloud Storage HMAC key: https://cloud.google.com/storage/docs/authentication/managing-hmackeys#create
    2. Change endpoint_url to a Google Cloud Storage XML API endpoint.

    To learn more about HMAC: https://cloud.google.com/storage/docs/authentication/hmackeys#overview
    """
    client = boto3.client(
        "s3",
        region_name="auto",
        endpoint_url="https://storage.googleapis.com",
        aws_access_key_id=google_access_key_id,
        aws_secret_access_key=google_access_key_secret,
    )

    # Call GCS to list objects in bucket_name
    response = client.list_objects(Bucket=bucket_name)

    # Return list of object names in bucket
    results = []
    for blob in response["Contents"]:
        results.append(blob["Key"])
        print(blob["Key"])  # Can remove if not needed after development
    return results

Passaggi successivi

Per cercare e filtrare esempi di codice per altri prodotti Google Cloud, consulta il browser di esempio Google Cloud.