how to upload file and download file use oss-go-sdk

In this tutorial you will use the PutObject to upload a file, and use GetObject to download a file.

First read getting start

Preapare

Upload a file need a exists bucket, if you create the bucket skip this setup.

var bucket = "ossgosdkfileuploaddownload"

if err = OSSAPI.PutBucket(bucket, oss.ACLPublicReadWrite, nil, nil); err != nil {
	var e = oss.ParseError(err)
	log.Printf("Code: %s\nMessage: %s\n", e.Code, e.Message)
}

upload a file

Use PutObject to upload a file.

First defined a function upload.

func upload(OSSAPI *oss.API, bucket, filename, contentType string) {
	fp, err := os.Open(filename)
	defer fp.Close()
	if err != nil {
		log.Fatal(err)
	}

	var headers = make(map[string]string)
	headers["Content-Type"] = contentType

	if err = OSSAPI.PutObject(bucket, filename, fp, headers); err != nil {
		var e = oss.ParseError(err)
		log.Printf("Code: %s\nMessage: %s\n", e.Code, e.Message)
	}
}

Once upload created upload the <test.jpg> to OSS

upload(OSSAPI, bucket, "test.jpg", "image/jpeg")

then you can view the file on http://ossgosdkfileuploaddownload.oss-cn-hangzhou.aliyuncs.com/test.jpg

download a file from OSS

Use GetObject to download file from bucket.

GetObject return a io.Reader that use io.Copy copy the return data to a file.

first import the require package os, io, then defined download function.

func download(OSSAPI *oss.API, bucket, object, filename string) {
	var fp, err = os.Create(filename)
	if err != nil {
		log.Fatal(err)
	}
	defer fp.Close()
	var reader io.Reader
	if reader, err = OSSAPI.GetObject(bucket, object, nil, nil); err != nil {
		log.Fatal(err)
	}
	io.Copy(fp, reader)
}

Once create the download, download <test.jpg>

download(OSSAPI, bucket, "test.jpg", "test-download.jpg")

then you can find the test-download.jpg on the current dectory.

The end

the source code main.go