minio/pkg/fs/fs-bucket-listobjects.go

179 lines
5.3 KiB
Go

/*
* Minio Cloud Storage, (C) 2015-2016 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 fs
import (
"fmt"
"net/url"
"os"
"path"
"path/filepath"
"strings"
"github.com/minio/minio/pkg/probe"
)
// ListObjects - lists all objects for a given prefix, returns up to
// maxKeys number of objects per call.
func (fs Filesystem) ListObjects(bucket, prefix, marker, delimiter string, maxKeys int) (ListObjectsResult, *probe.Error) {
result := ListObjectsResult{}
var queryPrefix string
// Input validation.
if !IsValidBucketName(bucket) {
return result, probe.NewError(BucketNameInvalid{Bucket: bucket})
}
bucket = fs.denormalizeBucket(bucket)
bucketDir := filepath.Join(fs.path, bucket)
// Verify if bucket exists.
if status, err := isDirExist(bucketDir); !status {
if err == nil {
// File exists, but its not a directory.
return result, probe.NewError(BucketNotFound{Bucket: bucket})
} else if os.IsNotExist(err) {
// File does not exist.
return result, probe.NewError(BucketNotFound{Bucket: bucket})
} else {
return result, probe.NewError(err)
}
}
if !IsValidObjectPrefix(prefix) {
return result, probe.NewError(ObjectNameInvalid{Bucket: bucket, Object: prefix})
}
// Verify if delimiter is anything other than '/', which we do not support.
if delimiter != "" && delimiter != "/" {
return result, probe.NewError(fmt.Errorf("delimiter '%s' is not supported", delimiter))
}
// Marker is set unescape.
if marker != "" {
if markerUnescaped, err := url.QueryUnescape(marker); err == nil {
marker = markerUnescaped
} else {
return result, probe.NewError(err)
}
if !strings.HasPrefix(marker, prefix) {
return result, probe.NewError(fmt.Errorf("Invalid combination of marker '%s' and prefix '%s'", marker, prefix))
}
}
// Return empty response for a valid request when maxKeys is 0.
if maxKeys == 0 {
return result, nil
}
// Over flowing maxkeys - reset to listObjectsLimit.
if maxKeys < 0 || maxKeys > listObjectsLimit {
maxKeys = listObjectsLimit
}
// Verify if prefix exists.
prefixDir := filepath.Dir(filepath.FromSlash(prefix))
rootDir := filepath.Join(bucketDir, prefixDir)
_, err := isDirExist(rootDir)
if err != nil {
if os.IsNotExist(err) {
// Prefix does not exist, not an error just respond empty
// list response.
return result, nil
}
// Rest errors should be treated as failure.
return result, probe.NewError(err)
}
recursive := true
skipDir := true
if delimiter == "/" {
skipDir = false
recursive = false
}
// Maximum 1000 objects returned in a single to listObjects.
// Further calls will set right marker value to continue reading the rest of the objectList.
// popListObjectCh returns nil if the call to ListObject is done for the first time.
// On further calls to ListObjects to retrive more objects within the timeout period,
// popListObjectCh returns the channel from which rest of the objects can be retrieved.
objectInfoCh := fs.popListObjectCh(ListObjectParams{bucket, delimiter, marker, prefix})
if objectInfoCh == nil {
if prefix != "" {
// queryPrefix variable is set to value of the prefix to be searched.
// If prefix contains directory hierarchy queryPrefix is set to empty string,
// this ensure that all objects inside the prefixDir is listed.
// Otherwise the base name is extracted from path.Base and it'll be will be set to Querystring.
// if prefix = /Asia/India/, queryPrefix will be set to empty string(""), so that all objects in prefixDir are listed.
// if prefix = /Asia/India/summerpics , Querystring will be set to "summerpics",
// so those all objects with the prefix "summerpics" inside the /Asia/India/ prefix folder gets listed.
if prefix[len(prefix)-1:] == "/" {
queryPrefix = ""
} else {
queryPrefix = path.Base(prefix)
}
}
ch := treeWalk(rootDir, bucketDir, recursive, queryPrefix)
objectInfoCh = &ch
}
nextMarker := ""
for i := 0; i < maxKeys; {
objInfo, ok := objectInfoCh.Read()
if !ok {
// Closed channel.
return result, nil
}
if objInfo.Err != nil {
return ListObjectsResult{}, probe.NewError(objInfo.Err)
}
if strings.Contains(objInfo.Name, "$multiparts") || strings.Contains(objInfo.Name, "$tmpobject") {
continue
}
if objInfo.IsDir && skipDir {
continue
}
// Add the bucket.
objInfo.Bucket = bucket
// In case its not the first call to ListObjects (before timeout),
// The result is already inside the buffered channel.
if objInfo.Name > marker {
if objInfo.IsDir {
result.Prefixes = append(result.Prefixes, objInfo.Name)
} else {
result.Objects = append(result.Objects, objInfo)
}
nextMarker = objInfo.Name
i++
}
}
if !objectInfoCh.IsClosed() {
result.IsTruncated = true
result.NextMarker = nextMarker
fs.pushListObjectCh(ListObjectParams{bucket, delimiter, nextMarker, prefix}, *objectInfoCh)
}
return result, nil
}