From 74a496e44ad196feff294f659e9c4d9a3724f53b Mon Sep 17 00:00:00 2001
From: Knut Ahlers <knut@ahlers.me>
Date: Sun, 30 Jun 2019 05:33:34 +0200
Subject: [PATCH] Add prefix sync for s3 buckets

Signed-off-by: Knut Ahlers <knut@ahlers.me>
---
 providers/s3/file.go     |  4 +++-
 providers/s3/provider.go | 19 ++++++++++++++-----
 2 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/providers/s3/file.go b/providers/s3/file.go
index 8f31d41..0fc8075 100644
--- a/providers/s3/file.go
+++ b/providers/s3/file.go
@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"hash"
 	"io"
+	"strings"
 	"time"
 
 	"github.com/aws/aws-sdk-go/aws"
@@ -22,11 +23,12 @@ type File struct {
 
 	s3Conn *s3.S3
 	bucket string
+	prefix string
 }
 
 func (f File) Info() providers.FileInfo {
 	return providers.FileInfo{
-		RelativeName: f.key,
+		RelativeName: strings.Trim(strings.TrimPrefix(f.key, f.prefix), "/"),
 		LastModified: f.lastModified,
 		Checksum:     f.checksum,
 		Size:         f.size,
diff --git a/providers/s3/provider.go b/providers/s3/provider.go
index f59c302..194f110 100644
--- a/providers/s3/provider.go
+++ b/providers/s3/provider.go
@@ -24,6 +24,7 @@ type Provider struct {
 	bucket       string
 	bucketRegion string
 	defaultACL   string
+	prefix       string
 	s3           *s3.S3
 }
 
@@ -56,6 +57,7 @@ func New(uri string) (providers.CloudProvider, error) {
 		bucket:       u.Host,
 		bucketRegion: region,
 		defaultACL:   s3.ObjectCannedACLPrivate,
+		prefix:       strings.Trim(u.Path, "/"),
 		s3:           svc,
 	}
 
@@ -75,7 +77,7 @@ func (p *Provider) GetChecksumMethod() hash.Hash { return md5.New() }
 func (p *Provider) DeleteFile(relativeName string) error {
 	_, err := p.s3.DeleteObject(&s3.DeleteObjectInput{
 		Bucket: aws.String(p.bucket),
-		Key:    aws.String(relativeName),
+		Key:    p.relativeNameToKey(relativeName),
 	})
 
 	return errors.Wrap(err, "Unable to delete object")
@@ -84,7 +86,7 @@ func (p *Provider) DeleteFile(relativeName string) error {
 func (p *Provider) GetFile(relativeName string) (providers.File, error) {
 	resp, err := p.s3.HeadObject(&s3.HeadObjectInput{
 		Bucket: aws.String(p.bucket),
-		Key:    aws.String(relativeName),
+		Key:    p.relativeNameToKey(relativeName),
 	})
 	if err != nil {
 		return nil, errors.Wrap(err, "Unable to fetch head information")
@@ -106,6 +108,7 @@ func (p *Provider) ListFiles() ([]providers.File, error) {
 
 	err := p.s3.ListObjectsPages(&s3.ListObjectsInput{
 		Bucket: aws.String(p.bucket),
+		Prefix: aws.String(p.prefix),
 	}, func(out *s3.ListObjectsOutput, lastPage bool) bool {
 		for _, obj := range out.Contents {
 			files = append(files, File{
@@ -116,6 +119,7 @@ func (p *Provider) ListFiles() ([]providers.File, error) {
 
 				s3Conn: p.s3,
 				bucket: p.bucket,
+				prefix: p.prefix,
 			})
 		}
 
@@ -141,7 +145,7 @@ func (p *Provider) PutFile(f providers.File) (providers.File, error) {
 		ACL:    aws.String(p.getFileACL(f.Info().RelativeName)),
 		Body:   bytes.NewReader(buf.Bytes()),
 		Bucket: aws.String(p.bucket),
-		Key:    aws.String(f.Info().RelativeName),
+		Key:    p.relativeNameToKey(f.Info().RelativeName),
 	}); err != nil {
 		return nil, errors.Wrap(err, "Unable to write file")
 	}
@@ -153,7 +157,7 @@ func (p *Provider) Share(relativeName string) (string, error) {
 	_, err := p.s3.PutObjectAcl(&s3.PutObjectAclInput{
 		ACL:    aws.String(s3.ObjectCannedACLPublicRead),
 		Bucket: aws.String(p.bucket),
-		Key:    aws.String(relativeName),
+		Key:    p.relativeNameToKey(relativeName),
 	})
 	if err != nil {
 		return "", errors.Wrap(err, "Unable to publish file")
@@ -165,7 +169,7 @@ func (p *Provider) Share(relativeName string) (string, error) {
 func (p *Provider) getFileACL(relativeName string) string {
 	objACL, err := p.s3.GetObjectAcl(&s3.GetObjectAclInput{
 		Bucket: aws.String(p.bucket),
-		Key:    aws.String(relativeName),
+		Key:    p.relativeNameToKey(relativeName),
 	})
 
 	if err != nil {
@@ -183,3 +187,8 @@ func (p *Provider) getFileACL(relativeName string) string {
 
 	return p.defaultACL
 }
+
+func (p Provider) relativeNameToKey(relativeName string) *string {
+	key := strings.Join([]string{p.prefix, relativeName}, "/")
+	return &key
+}