By using the bucket tagging function, you can classify your buckets to manage them. For example, you can specify that only buckets with specified tags are returned in ListBucket operations.

  • Only the bucket owner and authorized RAM users can add tags to a bucket. Otherwise, the 403 Forbidden error is returned with the error code: AccessDenied.
  • You can add a maximum of 20 tags (key-value pairs) to a bucket.
  • The maximum size of a key is 64 bytes. The key of a tag cannot be null and cannot be prefixed with http://, https://, or Aliyun.
  • The maximum size of a tag value is 128 bytes. The value of a tag can be null.
  • The key and value of a tag must be UTF-8 encoded.
  • If you use PutBucketTagging to add tags to a bucket, the original tags added to the bucket are completely overwritten.

Add tags to a bucket

You can run the following code to add tags to a bucket: 
package main

import (
  "fmt"
  "os"

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

func main() {
  // Creates an OSSClient instance.
  client, err := oss.New("<yourEndpoint>", "<yourAccessKeyId>", "<yourAccessKeySecret>")
  if err != nil {
    fmt.Println("Error:", err)
    os.Exit(-1)
  }

  // Initializes the tags.
  tag1 := oss.Tag{
    Key:   "key1",
    Value: "value1",
  }
  tag2 := oss.Tag{
    Key:   "key2",
    Value: "value2",
  }
  tagging := oss.Tagging{
    Tags: []oss.Tag{tag1, tag2},
  }
  // Add the tags to the bucket.
  err = client.SetBucketTagging("yourBucketName", tagging)
  if err != nil {
    fmt.Println("Error:", err)
    os.Exit(-1)
  }
}

Obtain the tags added to a bucket

You can run the following code to obtain the tags added to a bucket: 
package main

import (
  "fmt"
  "os"

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

func main() {
  // Creates an OSSClient instance.
  client, err := oss.New("<yourEndpoint>", "<yourAccessKeyId>", "<yourAccessKeySecret>")
  if err != nil {
    fmt.Println("Error:", err)
    os.Exit(-1)
  }

  // Obtains the tags added to the bucket.
  ret, err := client.GetBucketTagging("yourBucketName")
  if err != nil {
    fmt.Println("Error:", err)
    os.Exit(-1)
  }
  // Prints the number of tags added to the bucket.
  fmt.Println("Tag length: ", len(ret.Tags))
}

List buckets with a specified tag

Run the following code to list buckets with a specified tag: 
package main

import (
  "fmt"
  "os"

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

func main() {
  // Creates an OSSClient.
  client, err := oss.New("<yourEndpoint>", "<yourAccessKeyId>", "<yourAccessKeySecret>")
  if err != nil {
    fmt.Println("Error:", err)
    os.Exit(-1)
  }

  // Searches for the bucket based on TagKey.
  ret, err := client.ListBuckets(oss.TagKey("yourTaggingKey"))
  if err != nil {
    fmt.Println("Error:", err)
    os.Exit(-1)
  }
  // Prints the bucket information.
  for _, bucket := range ret.Buckets{
    fmt.Println("bucket:", bucket)
  }
  // Searches for the bucket based on TagKey and TagValue.
  // TagValue must be used with TagKey. You can leave the value of TagValue as null. In this case, TagValue is not used as a filter to search for the bucket.
  res, err := client.ListBuckets(oss.TagKey("yourTaggingKey"), oss.TagValue("yourTaggingValue"))
  if err != nil {
    fmt.Println("Error:", err)
    os.Exit(-1)
  }
  // Prints the bucket information.
  for _, b := range res.Buckets{
    fmt.Println("bucket:", b)
  }
}

Delete the tags added to a bucket

You can run the following code to delete the tags added to a bucket: 
package main

import (
  "fmt"
  "os"

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

func main() {
  // Creates an OSSClient instance.
  client, err := oss.New("<yourEndpoint>", "<yourAccessKeyId>", "<yourAccessKeySecret>")
  if err != nil {
    fmt.Println("Error:", err)
    os.Exit(-1)
  }
  // Deletes the tags added to the bucket.
  err = client.DeleteBucketTagging("yourBucketName")
  if err != nil {
    fmt.Println("Error:", err)
    os.Exit(-1)
  }
}