Cloud Storage (第 1 代) Hello World

函式範例由 Storage 觸發，並在 Cloud Functions (第 1 代) 上執行。

深入探索

如需包含這個程式碼範例的詳細說明文件，請參閱下列文章：

程式碼範例

C#

如要在 Cloud Run functions 啟用驗證功能，請設定應用程式預設憑證。詳情請參閱這篇文章，瞭解如何設定本機開發環境的驗證機制。

using CloudNative.CloudEvents;
using Google.Cloud.Functions.Framework;
using Google.Events.Protobuf.Cloud.Storage.V1;
using Microsoft.Extensions.Logging;
using System.Threading;
using System.Threading.Tasks;

namespace HelloGcs;

 /// <summary>
 /// Example Cloud Storage-triggered function.
 /// This function can process any event from Cloud Storage.
 /// </summary>
public class Function : ICloudEventFunction<StorageObjectData>
{
    private readonly ILogger _logger;

    public Function(ILogger<Function> logger) =>
        _logger = logger;

    public Task HandleAsync(CloudEvent cloudEvent, StorageObjectData data, CancellationToken cancellationToken)
    {
        _logger.LogInformation("Event: {event}", cloudEvent.Id);
        _logger.LogInformation("Event Type: {type}", cloudEvent.Type);
        _logger.LogInformation("Bucket: {bucket}", data.Bucket);
        _logger.LogInformation("File: {file}", data.Name);
        _logger.LogInformation("Metageneration: {metageneration}", data.Metageneration);
        _logger.LogInformation("Created: {created:s}", data.TimeCreated?.ToDateTimeOffset());
        _logger.LogInformation("Updated: {updated:s}", data.Updated?.ToDateTimeOffset());
        return Task.CompletedTask;
    }
}

Go

如要在 Cloud Run functions 啟用驗證功能，請設定應用程式預設憑證。詳情請參閱這篇文章，瞭解如何設定本機開發環境的驗證機制。


// Package helloworld provides a set of Cloud Functions samples.
package helloworld

import (
	"context"
	"fmt"
	"log"
	"time"

	"cloud.google.com/go/functions/metadata"
)

// GCSEvent is the payload of a GCS event.
type GCSEvent struct {
	Kind                    string                 `json:"kind"`
	ID                      string                 `json:"id"`
	SelfLink                string                 `json:"selfLink"`
	Name                    string                 `json:"name"`
	Bucket                  string                 `json:"bucket"`
	Generation              string                 `json:"generation"`
	Metageneration          string                 `json:"metageneration"`
	ContentType             string                 `json:"contentType"`
	TimeCreated             time.Time              `json:"timeCreated"`
	Updated                 time.Time              `json:"updated"`
	TemporaryHold           bool                   `json:"temporaryHold"`
	EventBasedHold          bool                   `json:"eventBasedHold"`
	RetentionExpirationTime time.Time              `json:"retentionExpirationTime"`
	StorageClass            string                 `json:"storageClass"`
	TimeStorageClassUpdated time.Time              `json:"timeStorageClassUpdated"`
	Size                    string                 `json:"size"`
	MD5Hash                 string                 `json:"md5Hash"`
	MediaLink               string                 `json:"mediaLink"`
	ContentEncoding         string                 `json:"contentEncoding"`
	ContentDisposition      string                 `json:"contentDisposition"`
	CacheControl            string                 `json:"cacheControl"`
	Metadata                map[string]interface{} `json:"metadata"`
	CRC32C                  string                 `json:"crc32c"`
	ComponentCount          int                    `json:"componentCount"`
	Etag                    string                 `json:"etag"`
	CustomerEncryption      struct {
		EncryptionAlgorithm string `json:"encryptionAlgorithm"`
		KeySha256           string `json:"keySha256"`
	}
	KMSKeyName    string `json:"kmsKeyName"`
	ResourceState string `json:"resourceState"`
}

// HelloGCS consumes a(ny) GCS event.
func HelloGCS(ctx context.Context, e GCSEvent) error {
	meta, err := metadata.FromContext(ctx)
	if err != nil {
		return fmt.Errorf("metadata.FromContext: %w", err)
	}
	log.Printf("Event ID: %v\n", meta.EventID)
	log.Printf("Event type: %v\n", meta.EventType)
	log.Printf("Bucket: %v\n", e.Bucket)
	log.Printf("File: %v\n", e.Name)
	log.Printf("Metageneration: %v\n", e.Metageneration)
	log.Printf("Created: %v\n", e.TimeCreated)
	log.Printf("Updated: %v\n", e.Updated)
	return nil
}

Java

如要在 Cloud Run functions 啟用驗證功能，請設定應用程式預設憑證。詳情請參閱這篇文章，瞭解如何設定本機開發環境的驗證機制。

import com.google.cloud.functions.BackgroundFunction;
import com.google.cloud.functions.Context;
import functions.eventpojos.GcsEvent;
import java.util.logging.Logger;

/**
 * Example Cloud Storage-triggered function.
 * This function can process any event from Cloud Storage.
 */
public class HelloGcs implements BackgroundFunction<GcsEvent> {
  private static final Logger logger = Logger.getLogger(HelloGcs.class.getName());

  @Override
  public void accept(GcsEvent event, Context context) {
    logger.info("Event: " + context.eventId());
    logger.info("Event Type: " + context.eventType());
    logger.info("Bucket: " + event.getBucket());
    logger.info("File: " + event.getName());
    logger.info("Metageneration: " + event.getMetageneration());
    logger.info("Created: " + event.getTimeCreated());
    logger.info("Updated: " + event.getUpdated());
  }
}

Node.js

如要在 Cloud Run functions 啟用驗證功能，請設定應用程式預設憑證。詳情請參閱這篇文章，瞭解如何設定本機開發環境的驗證機制。

/**
 * Generic background Cloud Function to be triggered by Cloud Storage.
 * This sample works for all Cloud Storage CRUD operations.
 *
 * @param {object} file The Cloud Storage file metadata.
 * @param {object} context The event metadata.
 */
exports.helloGCS = (file, context) => {
  console.log(`  Event: ${context.eventId}`);
  console.log(`  Event Type: ${context.eventType}`);
  console.log(`  Bucket: ${file.bucket}`);
  console.log(`  File: ${file.name}`);
  console.log(`  Metageneration: ${file.metageneration}`);
  console.log(`  Created: ${file.timeCreated}`);
  console.log(`  Updated: ${file.updated}`);
};

PHP

如要在 Cloud Run functions 啟用驗證功能，請設定應用程式預設憑證。詳情請參閱這篇文章，瞭解如何設定本機開發環境的驗證機制。


use CloudEvents\V1\CloudEventInterface;
use Google\CloudFunctions\FunctionsFramework;

// Register the function with Functions Framework.
// This enables omitting the `FUNCTIONS_SIGNATURE_TYPE=cloudevent` environment
// variable when deploying. The `FUNCTION_TARGET` environment variable should
// match the first parameter.
FunctionsFramework::cloudEvent('helloGCS', 'helloGCS');

function helloGCS(CloudEventInterface $cloudevent)
{
    // This function supports all Cloud Storage event types.
    $log = fopen(getenv('LOGGER_OUTPUT') ?: 'php://stderr', 'wb');
    $data = $cloudevent->getData();
    fwrite($log, 'Event: ' . $cloudevent->getId() . PHP_EOL);
    fwrite($log, 'Event Type: ' . $cloudevent->getType() . PHP_EOL);
    fwrite($log, 'Bucket: ' . $data['bucket'] . PHP_EOL);
    fwrite($log, 'File: ' . $data['name'] . PHP_EOL);
    fwrite($log, 'Metageneration: ' . $data['metageneration'] . PHP_EOL);
    fwrite($log, 'Created: ' . $data['timeCreated'] . PHP_EOL);
    fwrite($log, 'Updated: ' . $data['updated'] . PHP_EOL);
}

Python

如要在 Cloud Run functions 啟用驗證功能，請設定應用程式預設憑證。詳情請參閱這篇文章，瞭解如何設定本機開發環境的驗證機制。

def hello_gcs(event, context):
    """Background Cloud Function to be triggered by Cloud Storage.
       This generic function logs relevant data when a file is changed,
       and works for all Cloud Storage CRUD operations.
    Args:
        event (dict):  The dictionary with data specific to this type of event.
                       The `data` field contains a description of the event in
                       the Cloud Storage `object` format described here:
                       https://cloud.google.com/storage/docs/json_api/v1/objects#resource
        context (google.cloud.functions.Context): Metadata of triggering event.
    Returns:
        None; the output is written to Cloud Logging
    """

    print(f"Event ID: {context.event_id}")
    print(f"Event type: {context.event_type}")
    print("Bucket: {}".format(event["bucket"]))
    print("File: {}".format(event["name"]))
    print("Metageneration: {}".format(event["metageneration"]))
    print("Created: {}".format(event["timeCreated"]))
    print("Updated: {}".format(event["updated"]))

Ruby

如要在 Cloud Run functions 啟用驗證功能，請設定應用程式預設憑證。詳情請參閱這篇文章，瞭解如何設定本機開發環境的驗證機制。

require "functions_framework"

FunctionsFramework.cloud_event "hello_gcs" do |event|
  # This function supports all Cloud Storage events.
  # The `event` parameter is a CloudEvents::Event::V1 object.
  # See https://cloudevents.github.io/sdk-ruby/latest/CloudEvents/Event/V1.html
  payload = event.data

  logger.info "Event: #{event.id}"
  logger.info "Event Type: #{event.type}"
  logger.info "Bucket: #{payload['bucket']}"
  logger.info "File: #{payload['name']}"
  logger.info "Metageneration: #{payload['metageneration']}"
  logger.info "Created: #{payload['timeCreated']}"
  logger.info "Updated: #{payload['updated']}"
end

後續步驟

如要搜尋及篩選其他 Google Cloud 產品的程式碼範例，請參閱Google Cloud 瀏覽器範例。