XL: Introduce new API StorageInfo. (#1770)

This is necessary for calculating the total storage
capacity from object layer. This value is also needed for
browser UI.

Buckets used to carry this information, this patch
deprecates this feature.

fs-v1.go

@@ -25,29 +25,31 @@ import (
 	"strings"
 	"sync"
 
+	"github.com/minio/minio/pkg/disk"
 	"github.com/minio/minio/pkg/mimedb"
 )
 
 // fsObjects - Implements fs object layer.
 type fsObjects struct {
 	storage            StorageAPI
+	physicalDisk       string
 	listObjectMap      map[listParams][]*treeWalkerFS
 	listObjectMapMutex *sync.Mutex
 }
 
 // newFSObjects - initialize new fs object layer.
-func newFSObjects(exportPath string) (ObjectLayer, error) {
+func newFSObjects(disk string) (ObjectLayer, error) {
 	var storage StorageAPI
 	var err error
-	if !strings.ContainsRune(exportPath, ':') || filepath.VolumeName(exportPath) != "" {
+	if !strings.ContainsRune(disk, ':') || filepath.VolumeName(disk) != "" {
 		// Initialize filesystem storage API.
-		storage, err = newPosix(exportPath)
+		storage, err = newPosix(disk)
 		if err != nil {
 			return nil, err
 		}
 	} else {
 		// Initialize rpc client storage API.
-		storage, err = newRPCClient(exportPath)
+		storage, err = newRPCClient(disk)
 		if err != nil {
 			return nil, err
 		}
@@ -60,11 +62,22 @@ func newFSObjects(exportPath string) (ObjectLayer, error) {
 	// Return successfully initialized object layer.
 	return fsObjects{
 		storage:            storage,
+		physicalDisk:       disk,
 		listObjectMap:      make(map[listParams][]*treeWalkerFS),
 		listObjectMapMutex: &sync.Mutex{},
 	}, nil
 }
 
+// StorageInfo - returns underlying storage statistics.
+func (fs fsObjects) StorageInfo() StorageInfo {
+	info, err := disk.GetInfo(fs.physicalDisk)
+	fatalIf(err, "Unable to get disk info "+fs.physicalDisk)
+	return StorageInfo{
+		Total: info.Total,
+		Free:  info.Free,
+	}
+}
+
 /// Bucket operations
 
 // MakeBucket - make a bucket.
@@ -92,8 +105,6 @@ func (fs fsObjects) GetBucketInfo(bucket string) (BucketInfo, error) {
 	return BucketInfo{
 		Name:    bucket,
 		Created: vi.Created,
-		Total:   vi.Total,
-		Free:    vi.Free,
 	}, nil
 }
 
@@ -113,8 +124,6 @@ func (fs fsObjects) ListBuckets() ([]BucketInfo, error) {
 		bucketInfos = append(bucketInfos, BucketInfo{
 			Name:    vol.Name,
 			Created: vol.Created,
-			Total:   vol.Total,
-			Free:    vol.Free,
 		})
 	}
 	sort.Sort(byBucketName(bucketInfos))

object-datatypes.go

@@ -18,12 +18,16 @@ package main
 
 import "time"
 
+// StorageInfo - represents total capacity of underlying storage.
+type StorageInfo struct {
+	Total int64 // Total disk space.
+	Free  int64 // Free total available disk space.
+}
+
 // BucketInfo - bucket name and create date
 type BucketInfo struct {
 	Name    string
 	Created time.Time
-	Total   int64
-	Free    int64
 }
 
 // ObjectInfo - object info.

object-interface.go

@@ -20,6 +20,9 @@ import "io"
 
 // ObjectLayer implements primitives for object API layer.
 type ObjectLayer interface {
+	// Storage operations.
+	StorageInfo() StorageInfo
+
 	// Bucket operations.
 	MakeBucket(bucket string) error
 	GetBucketInfo(bucket string) (bucketInfo BucketInfo, err error)

posix.go

@@ -202,15 +202,6 @@ func (s fsStorage) MakeVol(volume string) (err error) {
 
 // ListVols - list volumes.
 func (s fsStorage) ListVols() (volsInfo []VolInfo, err error) {
-	// Get disk info to be populated for VolInfo.
-	var diskInfo disk.Info
-	diskInfo, err = disk.GetInfo(s.diskPath)
-	if err != nil {
-		if os.IsNotExist(err) {
-			return nil, errDiskNotFound
-		}
-		return nil, err
-	}
 	volsInfo, err = listVols(s.diskPath)
 	if err != nil {
 		return nil, err
@@ -219,9 +210,6 @@ func (s fsStorage) ListVols() (volsInfo []VolInfo, err error) {
 		volInfo := VolInfo{
 			Name:    vol.Name,
 			Created: vol.Created,
-			Total:   diskInfo.Total,
-			Free:    diskInfo.Free,
-			FSType:  diskInfo.FSType,
 		}
 		volsInfo[i] = volInfo
 	}
@@ -244,24 +232,12 @@ func (s fsStorage) StatVol(volume string) (volInfo VolInfo, err error) {
 		}
 		return VolInfo{}, err
 	}
-	// Get disk info, to be returned back along with volume info.
-	var diskInfo disk.Info
-	diskInfo, err = disk.GetInfo(s.diskPath)
-	if err != nil {
-		if os.IsNotExist(err) {
-			return VolInfo{}, errDiskNotFound
-		}
-		return VolInfo{}, err
-	}
 	// As os.Stat() doesn't carry other than ModTime(), use ModTime()
 	// as CreatedTime.
 	createdTime := st.ModTime()
 	return VolInfo{
 		Name:    volume,
 		Created: createdTime,
-		Free:    diskInfo.Free,
-		Total:   diskInfo.Total,
-		FSType:  diskInfo.FSType,
 	}, nil
 }
 

storage-datatypes.go

@@ -25,9 +25,6 @@ import (
 type VolInfo struct {
 	Name    string
 	Created time.Time
-	Total   int64
-	Free    int64
-	FSType  string
 }
 
 // FileInfo - file stat information.

web-handlers.go

@@ -98,6 +98,22 @@ func (web *webAPIHandlers) ServerInfo(r *http.Request, args *WebGenericArgs, rep
 	return nil
 }
 
+// StorageInfoRep - contains storage usage statistics.
+type StorageInfoRep struct {
+	StorageInfo StorageInfo `json:"storageInfo"`
+	UIVersion   string      `json:"uiVersion"`
+}
+
+// StorageInfo - web call to gather storage usage statistics.
+func (web *webAPIHandlers) StorageInfo(r *http.Request, args *GenericArgs, reply *StorageInfoRep) error {
+	if !isJWTReqAuthenticated(r) {
+		return &json2.Error{Message: "Unauthorized request"}
+	}
+	reply.UIVersion = miniobrowser.UIVersion
+	reply.StorageInfo = web.ObjectAPI.StorageInfo()
+	return nil
+}
+
 // MakeBucketArgs - make bucket args.
 type MakeBucketArgs struct {
 	BucketName string `json:"bucketName"`
@@ -127,10 +143,6 @@ type WebBucketInfo struct {
 	Name string `json:"name"`
 	// Date the bucket was created.
 	CreationDate time.Time `json:"creationDate"`
-	// Total storage space where the bucket resides.
-	Total int64 `json:"total"`
-	// Free storage space where the bucket resides.
-	Free int64 `json:"free"`
 }
 
 // ListBuckets - list buckets api.
@@ -148,8 +160,6 @@ func (web *webAPIHandlers) ListBuckets(r *http.Request, args *WebGenericArgs, re
 			reply.Buckets = append(reply.Buckets, WebBucketInfo{
 				Name:         bucket.Name,
 				CreationDate: bucket.Created,
-				Total:        bucket.Total,
-				Free:         bucket.Free,
 			})
 		}
 	}

xl-v1.go

@@ -20,8 +20,11 @@ import (
 	"errors"
 	"fmt"
 	"path/filepath"
+	"sort"
 	"strings"
 	"sync"
+
+	"github.com/minio/minio/pkg/disk"
 )
 
 const (
@@ -33,6 +36,7 @@ const (
 // xlObjects - Implements fs object layer.
 type xlObjects struct {
 	storageDisks       []StorageAPI
+	physicalDisks      []string
 	dataBlocks         int
 	parityBlocks       int
 	readQuorum         int
@@ -147,6 +151,7 @@ func newXLObjects(disks []string) (ObjectLayer, error) {
 
 	xl := xlObjects{
 		storageDisks:       newPosixDisks,
+		physicalDisks:      disks,
 		dataBlocks:         dataBlocks,
 		parityBlocks:       parityBlocks,
 		listObjectMap:      make(map[listParams][]*treeWalker),
@@ -168,3 +173,36 @@ func newXLObjects(disks []string) (ObjectLayer, error) {
 	// Return successfully initialized object layer.
 	return xl, nil
 }
+
+// byDiskTotal is a collection satisfying sort.Interface.
+type byDiskTotal []disk.Info
+
+func (d byDiskTotal) Len() int      { return len(d) }
+func (d byDiskTotal) Swap(i, j int) { d[i], d[j] = d[j], d[i] }
+func (d byDiskTotal) Less(i, j int) bool {
+	return d[i].Total < d[j].Total
+}
+
+// StorageInfo - returns underlying storage statistics.
+func (xl xlObjects) StorageInfo() StorageInfo {
+	var disksInfo []disk.Info
+	for _, diskPath := range xl.physicalDisks {
+		info, err := disk.GetInfo(diskPath)
+		if err != nil {
+			errorIf(err, "Unable to fetch disk info for "+diskPath)
+			continue
+		}
+		disksInfo = append(disksInfo, info)
+	}
+
+	// Sort so that the first element is the smallest.
+	sort.Sort(byDiskTotal(disksInfo))
+
+	// Return calculated storage info, choose the lowest Total and
+	// Free as the total aggregated values. Total capacity is always
+	// the multiple of smallest disk among the disk list.
+	return StorageInfo{
+		Total: disksInfo[0].Total * int64(len(xl.storageDisks)),
+		Free:  disksInfo[0].Free * int64(len(xl.storageDisks)),
+	}
+}