xl/fs: Split object layer into interface. (#1415)

2025-11-28 13:09:09 -05:00 · 2016-04-29 14:24:10 -07:00
parent 4d1b3d5e9a
commit 4e34e03dd4
61 changed files with 1815 additions and 1037 deletions
--- a/xl-objects.go
+++ b/xl-objects.go
@@ -0,0 +1,395 @@
+/*
+ * Minio Cloud Storage, (C) 2016 Minio, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package main
+
+import (
+	"crypto/md5"
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"io"
+	"path/filepath"
+	"sort"
+	"strings"
+
+	"github.com/minio/minio/pkg/mimedb"
+)
+
+const (
+	multipartMetaFile = "multipart.json"
+)
+
+// xlObjects - Implements fs object layer.
+type xlObjects struct {
+	storage StorageAPI
+}
+
+// newXLObjects - initialize new xl object layer.
+func newXLObjects(exportPaths ...string) (ObjectLayer, error) {
+	storage, err := newXL(exportPaths...)
+	if err != nil {
+		return nil, err
+	}
+	return xlObjects{storage}, nil
+}
+
+// checks whether bucket exists.
+func (xl xlObjects) isBucketExist(bucketName string) (bool, error) {
+	// Check whether bucket exists.
+	if _, e := xl.storage.StatVol(bucketName); e != nil {
+		if e == errVolumeNotFound {
+			return false, nil
+		}
+		return false, e
+	}
+	return true, nil
+}
+
+/// Bucket operations
+
+// MakeBucket - make a bucket.
+func (xl xlObjects) MakeBucket(bucket string) error {
+	// Verify if bucket is valid.
+	if !IsValidBucketName(bucket) {
+		return BucketNameInvalid{Bucket: bucket}
+	}
+	if err := xl.storage.MakeVol(bucket); err != nil {
+		return toObjectErr(err, bucket)
+	}
+	// This happens for the first time, but keep this here since this
+	// is the only place where it can be made expensive optimizing all
+	// other calls.
+	// Create minio meta volume, if it doesn't exist yet.
+	if err := xl.storage.MakeVol(minioMetaVolume); err != nil {
+		if err != errVolumeExists {
+			return toObjectErr(err, minioMetaVolume)
+		}
+	}
+	return nil
+}
+
+// GetBucketInfo - get bucket info.
+func (xl xlObjects) GetBucketInfo(bucket string) (BucketInfo, error) {
+	// Verify if bucket is valid.
+	if !IsValidBucketName(bucket) {
+		return BucketInfo{}, BucketNameInvalid{Bucket: bucket}
+	}
+	vi, err := xl.storage.StatVol(bucket)
+	if err != nil {
+		return BucketInfo{}, toObjectErr(err, bucket)
+	}
+	return BucketInfo{
+		Name:    bucket,
+		Created: vi.Created,
+		Total:   vi.Total,
+		Free:    vi.Free,
+	}, nil
+}
+
+// ListBuckets - list buckets.
+func (xl xlObjects) ListBuckets() ([]BucketInfo, error) {
+	var bucketInfos []BucketInfo
+	vols, err := xl.storage.ListVols()
+	if err != nil {
+		return nil, toObjectErr(err)
+	}
+	for _, vol := range vols {
+		// StorageAPI can send volume names which are incompatible
+		// with buckets, handle it and skip them.
+		if !IsValidBucketName(vol.Name) {
+			continue
+		}
+		bucketInfos = append(bucketInfos, BucketInfo{
+			Name:    vol.Name,
+			Created: vol.Created,
+			Total:   vol.Total,
+			Free:    vol.Free,
+		})
+	}
+	sort.Sort(byBucketName(bucketInfos))
+	return bucketInfos, nil
+}
+
+// DeleteBucket - delete a bucket.
+func (xl xlObjects) DeleteBucket(bucket string) error {
+	// Verify if bucket is valid.
+	if !IsValidBucketName(bucket) {
+		return BucketNameInvalid{Bucket: bucket}
+	}
+	if err := xl.storage.DeleteVol(bucket); err != nil {
+		return toObjectErr(err)
+	}
+	return nil
+}
+
+/// Object Operations
+
+// GetObject - get an object.
+func (xl xlObjects) GetObject(bucket, object string, startOffset int64) (io.ReadCloser, error) {
+	findPathOffset := func() (i int, partOffset int64, err error) {
+		partOffset = startOffset
+		for i = 1; i < 10000; i++ {
+			var fileInfo FileInfo
+			fileInfo, err = xl.storage.StatFile(bucket, pathJoin(object, fmt.Sprint(i)))
+			if err != nil {
+				if err == errFileNotFound {
+					continue
+				}
+				return
+			}
+			if partOffset < fileInfo.Size {
+				return
+
+			}
+			partOffset -= fileInfo.Size
+
+		}
+		err = errors.New("offset too high")
+		return
+	}
+
+	// Verify if bucket is valid.
+	if !IsValidBucketName(bucket) {
+		return nil, BucketNameInvalid{Bucket: bucket}
+	}
+	// Verify if object is valid.
+	if !IsValidObjectName(object) {
+		return nil, ObjectNameInvalid{Bucket: bucket, Object: object}
+	}
+	if _, err := xl.storage.StatFile(bucket, pathJoin(object, multipartMetaFile)); err != nil {
+		if _, err = xl.storage.StatFile(bucket, object); err == nil {
+			var reader io.ReadCloser
+			reader, err = xl.storage.ReadFile(bucket, object, startOffset)
+			if err != nil {
+				return nil, toObjectErr(err, bucket, object)
+			}
+			return reader, nil
+		}
+		return nil, toObjectErr(err, bucket, object)
+	}
+	fileReader, fileWriter := io.Pipe()
+	partNum, offset, err := findPathOffset()
+	if err != nil {
+		return nil, toObjectErr(err, bucket, object)
+	}
+	go func() {
+		for ; partNum < 10000; partNum++ {
+			r, err := xl.storage.ReadFile(bucket, pathJoin(object, fmt.Sprint(partNum)), offset)
+			if err != nil {
+				if err == errFileNotFound {
+					continue
+				}
+				fileWriter.CloseWithError(err)
+				return
+			}
+			if _, err := io.Copy(fileWriter, r); err != nil {
+				fileWriter.CloseWithError(err)
+				return
+			}
+		}
+		fileWriter.Close()
+	}()
+	return fileReader, nil
+}
+
+// GetObjectInfo - get object info.
+func (xl xlObjects) GetObjectInfo(bucket, object string) (ObjectInfo, error) {
+	getMultpartFileSize := func() (size int64) {
+		for i := 0; i < 10000; i++ {
+			fi, err := xl.storage.StatFile(bucket, pathJoin(object, fmt.Sprint(i)))
+			if err != nil {
+				continue
+			}
+			size += fi.Size
+		}
+		return size
+	}
+	// Verify if bucket is valid.
+	if !IsValidBucketName(bucket) {
+		return ObjectInfo{}, BucketNameInvalid{Bucket: bucket}
+	}
+	// Verify if object is valid.
+	if !IsValidObjectName(object) {
+		return ObjectInfo{}, ObjectNameInvalid{Bucket: bucket, Object: object}
+	}
+	fi, err := xl.storage.StatFile(bucket, object)
+	if err != nil {
+		fi, err = xl.storage.StatFile(bucket, pathJoin(object, multipartMetaFile))
+		if err != nil {
+			return ObjectInfo{}, toObjectErr(err, bucket, object)
+		}
+		fi.Size = getMultpartFileSize()
+	}
+	contentType := "application/octet-stream"
+	if objectExt := filepath.Ext(object); objectExt != "" {
+		content, ok := mimedb.DB[strings.ToLower(strings.TrimPrefix(objectExt, "."))]
+		if ok {
+			contentType = content.ContentType
+		}
+	}
+	return ObjectInfo{
+		Bucket:      bucket,
+		Name:        object,
+		ModTime:     fi.ModTime,
+		Size:        fi.Size,
+		IsDir:       fi.Mode.IsDir(),
+		ContentType: contentType,
+		MD5Sum:      "", // Read from metadata.
+	}, nil
+}
+
+func (xl xlObjects) PutObject(bucket string, object string, size int64, data io.Reader, metadata map[string]string) (string, error) {
+	// Verify if bucket is valid.
+	if !IsValidBucketName(bucket) {
+		return "", (BucketNameInvalid{Bucket: bucket})
+	}
+	if !IsValidObjectName(object) {
+		return "", (ObjectNameInvalid{
+			Bucket: bucket,
+			Object: object,
+		})
+	}
+	// Check whether the bucket exists.
+	isExist, err := xl.isBucketExist(bucket)
+	if err != nil {
+		return "", err
+	}
+	if !isExist {
+		return "", BucketNotFound{Bucket: bucket}
+	}
+
+	fileWriter, err := xl.storage.CreateFile(bucket, object)
+	if err != nil {
+		return "", toObjectErr(err, bucket, object)
+	}
+
+	// Initialize md5 writer.
+	md5Writer := md5.New()
+
+	// Instantiate a new multi writer.
+	multiWriter := io.MultiWriter(md5Writer, fileWriter)
+
+	// Instantiate checksum hashers and create a multiwriter.
+	if size > 0 {
+		if _, err = io.CopyN(multiWriter, data, size); err != nil {
+			if clErr := safeCloseAndRemove(fileWriter); clErr != nil {
+				return "", clErr
+			}
+			return "", toObjectErr(err)
+		}
+	} else {
+		if _, err = io.Copy(multiWriter, data); err != nil {
+			if clErr := safeCloseAndRemove(fileWriter); clErr != nil {
+				return "", clErr
+			}
+			return "", err
+		}
+	}
+
+	newMD5Hex := hex.EncodeToString(md5Writer.Sum(nil))
+	// md5Hex representation.
+	var md5Hex string
+	if len(metadata) != 0 {
+		md5Hex = metadata["md5Sum"]
+	}
+	if md5Hex != "" {
+		if newMD5Hex != md5Hex {
+			if err = safeCloseAndRemove(fileWriter); err != nil {
+				return "", err
+			}
+			return "", BadDigest{md5Hex, newMD5Hex}
+		}
+	}
+	err = fileWriter.Close()
+	if err != nil {
+		return "", err
+	}
+
+	// Return md5sum, successfully wrote object.
+	return newMD5Hex, nil
+}
+
+func (xl xlObjects) DeleteObject(bucket, object string) error {
+	// Verify if bucket is valid.
+	if !IsValidBucketName(bucket) {
+		return BucketNameInvalid{Bucket: bucket}
+	}
+	if !IsValidObjectName(object) {
+		return ObjectNameInvalid{Bucket: bucket, Object: object}
+	}
+	if err := xl.storage.DeleteFile(bucket, object); err != nil {
+		return toObjectErr(err, bucket, object)
+	}
+	return nil
+}
+
+func (xl xlObjects) ListObjects(bucket, prefix, marker, delimiter string, maxKeys int) (ListObjectsInfo, error) {
+	// Verify if bucket is valid.
+	if !IsValidBucketName(bucket) {
+		return ListObjectsInfo{}, BucketNameInvalid{Bucket: bucket}
+	}
+	if !IsValidObjectPrefix(prefix) {
+		return ListObjectsInfo{}, ObjectNameInvalid{Bucket: bucket, Object: prefix}
+	}
+	// Verify if delimiter is anything other than '/', which we do not support.
+	if delimiter != "" && delimiter != slashSeparator {
+		return ListObjectsInfo{}, UnsupportedDelimiter{
+			Delimiter: delimiter,
+		}
+	}
+	// Verify if marker has prefix.
+	if marker != "" {
+		if !strings.HasPrefix(marker, prefix) {
+			return ListObjectsInfo{}, InvalidMarkerPrefixCombination{
+				Marker: marker,
+				Prefix: prefix,
+			}
+		}
+	}
+
+	// Default is recursive, if delimiter is set then list non recursive.
+	recursive := true
+	if delimiter == slashSeparator {
+		recursive = false
+	}
+	fileInfos, eof, err := xl.storage.ListFiles(bucket, prefix, marker, recursive, maxKeys)
+	if err != nil {
+		return ListObjectsInfo{}, toObjectErr(err, bucket)
+	}
+	if maxKeys == 0 {
+		return ListObjectsInfo{}, nil
+	}
+
+	result := ListObjectsInfo{IsTruncated: !eof}
+	for _, fileInfo := range fileInfos {
+		// With delimiter set we fill in NextMarker and Prefixes.
+		if delimiter == slashSeparator {
+			result.NextMarker = fileInfo.Name
+			if fileInfo.Mode.IsDir() {
+				result.Prefixes = append(result.Prefixes, fileInfo.Name)
+				continue
+			}
+		}
+		result.Objects = append(result.Objects, ObjectInfo{
+			Name:    fileInfo.Name,
+			ModTime: fileInfo.ModTime,
+			Size:    fileInfo.Size,
+			IsDir:   false,
+		})
+	}
+	return result, nil
+}