#5 Add tag command to tag object/versions.

cmd/tags.go

@@ -0,0 +1,127 @@
+package cmd
+
+import (
+	"strings"
+
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/service/s3"
+	"github.com/spf13/cobra"
+)
+
+var tagRoot = &cobra.Command{
+	Use:   "tag",
+	Short: "Tag S3 object(s)",
+}
+
+func getTagMap(expectValue bool) map[string]string {
+	tagSet := make(map[string]string)
+	for _, t := range tagFlags.tags {
+		i := strings.IndexRune(t, '=')
+		switch {
+		case expectValue && i > 0:
+			tagSet[t[:i]] = t[i+1:]
+		case !expectValue && i > 0:
+			tagSet[t[:i]] = ""
+		case !expectValue:
+			tagSet[t] = ""
+		}
+	}
+	return tagSet
+}
+
+var tagAdd = &cobra.Command{
+	Use:          "add s3://bucket/folder/ s3://bucket/folder/prefix ...",
+	Short:        "Add tag(s) to S3 object(s)",
+	SilenceUsage: true,
+	RunE: func(_ *cobra.Command, urls []string) error {
+		svc := getS3()
+		return run(urls, accessFuncBuilder(func(bucket string, o *s3.ObjectVersion) error {
+			tagResp, err := svc.GetObjectTagging(&s3.GetObjectTaggingInput{
+				Bucket:    &bucket,
+				Key:       o.Key,
+				VersionId: o.VersionId,
+			})
+			if err != nil {
+				return err
+			}
+			ts := tagResp.TagSet
+			newTags := getTagMap(true)
+			for i := range ts {
+				if v, ok := newTags[*ts[i].Key]; ok {
+					ts[i].Value = aws.String(v) // copy
+					delete(newTags, *ts[i].Key)
+				}
+			}
+			for k, v := range newTags {
+				ts = append(ts, &s3.Tag{
+					Key:   aws.String(k),
+					Value: aws.String(v),
+				})
+			}
+
+			_, err = svc.PutObjectTagging(&s3.PutObjectTaggingInput{
+				Bucket:    &bucket,
+				Key:       o.Key,
+				VersionId: o.VersionId,
+				Tagging: &s3.Tagging{
+					TagSet: ts,
+				},
+			})
+			return err
+		}))
+	},
+}
+
+var tagRm = &cobra.Command{
+	Use:          "rm s3://bucket/folder/ s3://bucket/folder/prefix ...",
+	Short:        "remove tag(s) from S3 object(s)",
+	SilenceUsage: true,
+	RunE: func(_ *cobra.Command, urls []string) error {
+		svc := getS3()
+		return run(urls, accessFuncBuilder(func(bucket string, o *s3.ObjectVersion) error {
+			tagResp, err := svc.GetObjectTagging(&s3.GetObjectTaggingInput{
+				Bucket:    &bucket,
+				Key:       o.Key,
+				VersionId: o.VersionId,
+			})
+			if err != nil {
+				return err
+			}
+			ts := tagResp.TagSet
+			rmTags := getTagMap(false)
+			i := 0
+			for i < len(ts) {
+				if _, ok := rmTags[*ts[i].Key]; ok {
+					// remove an element in an array by swapping it with last element and reducing array size
+					ts[len(ts)-1], ts[i] = ts[i], ts[len(ts)-1]
+					ts = ts[:len(ts)-1]
+					continue
+				}
+				i++
+			}
+			_, err = svc.PutObjectTagging(&s3.PutObjectTaggingInput{
+				Bucket:    &bucket,
+				Key:       o.Key,
+				VersionId: o.VersionId,
+				Tagging: &s3.Tagging{
+					TagSet: ts,
+				},
+			})
+			return err
+		}))
+	},
+}
+
+func init() {
+	tagAdd.Flags().StringSliceVar(&tagFlags.tags, "tags", nil, "tags as --tags 'tag1=value1,tag2=value2' or multiple --tags ... options")
+	tagAdd.MarkFlagRequired("tags")
+	tagRm.Flags().StringSliceVar(&tagFlags.tags, "tags", nil, "tags as --tags 'tag1,tag2' or multiple --tags ... options")
+	tagRm.MarkFlagRequired("tags")
+	initVersionsConfig(tagRoot.PersistentFlags())
+	tagRoot.AddCommand(tagAdd, tagRm)
+	rootCmd.AddCommand(tagRoot)
+}
+
+var tagFlags struct {
+	tags []string
+}