Copy an object (OSS SDK for Go 1.0)

The following sample code provides an example on how to copy a large object by part:

package main

import (
	"log"
	"net/http"
	"time"

	"github.com/aliyun/aliyun-oss-go-sdk/oss"
)

func main() {
	// Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured. 
	provider, err := oss.NewEnvironmentVariableCredentialsProvider()
	if err != nil {
		log.Fatalf("Failed to create credentials provider: %v", err)
	}

	// Create an OSSClient instance. 
	// Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com. Specify your actual endpoint. 
	// Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou. Specify the actual region.
	clientOptions := []oss.ClientOption{oss.SetCredentialsProvider(&provider)}
	clientOptions = append(clientOptions, oss.Region("yourRegion"))
	// Specify the version of the signature algorithm.
	clientOptions = append(clientOptions, oss.AuthVersion(oss.AuthV4))
	client, err := oss.New("yourEndpoint", "", "", clientOptions...)
	if err != nil {
		log.Fatalf("Failed to create OSS client: %v", err)
	}

	// Specify the name of the bucket. 
	bucketName := "yourBucketName"
	bucket, err := client.Bucket(bucketName)
	if err != nil {
		log.Fatalf("Failed to get bucket '%s': %v", bucketName, err)
	}

	// Specify the full path of the object. Do not include the bucket name in the full path. 
	objectName := "yourObjectName"
	fileName := "yourFileName"
	futureDate := time.Date(2049, time.January, 10, 23, 0, 0, 0, time.UTC)
	var retHeader http.Header

	// Split the file.
	chunks, err := oss.SplitFileByPartNum(fileName, 3)
	if err != nil {
		log.Fatalf("Failed to split file '%s': %v", fileName, err)
	}

	// Upload a large object as the source object.
	err = bucket.PutObjectFromFile(objectName, fileName, oss.GetResponseHeader(&retHeader))
	if err != nil {
		log.Fatalf("Failed to put object '%s' from file '%s': %v", objectName, fileName, err)
	}

	// Query the version ID of the source object. 
	versionId := oss.GetVersionId(retHeader)
	log.Printf("Source object version ID: %s", versionId)

	// Configure the parameters for the object copy task.
	options := []oss.Option{
		oss.Expires(futureDate),
		oss.Meta("my", "myprop"),
	}

	// Specify the name of the destination object. 
	objectDest := objectName + "dest"
	var parts []oss.UploadPart
	copyOptions := []oss.Option{
		oss.VersionId(versionId),
		oss.GetResponseHeader(&retHeader),
	}

	// Initiate a multipart upload task.
	imu, err := bucket.InitiateMultipartUpload(objectDest, options...)
	if err != nil {
		log.Fatalf("Failed to initiate multipart upload for object '%s': %v", objectDest, err)
	}

	// Copy the large object.
	for _, chunk := range chunks {
		part, err := bucket.UploadPartCopy(imu, bucketName, objectName, chunk.Offset, chunk.Size, int(chunk.Number), copyOptions...)
		if err != nil {
			log.Fatalf("Failed to upload part %d of object '%s': %v", chunk.Number, objectName, err)
		}
		parts = append(parts, part)

		// Display the value of the x-oss-copy-source-version-id header. 
		log.Printf("x-oss-copy-source-version-id: %s", oss.GetCopySrcVersionId(retHeader))
	}

	// Complete the multipart upload task.
	_, err = bucket.CompleteMultipartUpload(imu, parts, oss.GetResponseHeader(&retHeader))
	if err != nil {
		log.Fatalf("Failed to complete multipart upload for object '%s': %v", objectDest, err)
	}

	// Display the value of the x-oss-version-id header. 
	log.Printf("x-oss-version-id: %s", oss.GetVersionId(retHeader))
}