minFreeSpace refactored

weed/util/minfreespace.go

@@ -0,0 +1,90 @@
+package util
+
+import (
+	"errors"
+	"fmt"
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"strconv"
+	"strings"
+)
+
+// MinFreeSpaceType is the type of MinFreeSpace.
+type MinFreeSpaceType int
+
+const (
+	// AsPercent set the MinFreeSpaceType to a percentage value from 0 to 100.
+	AsPercent MinFreeSpaceType = iota
+	// AsBytes set the MinFreeSpaceType to a absolute value bytes.
+	AsBytes
+)
+
+// MinFreeSpace is type that defines the limit for the minimum free space.
+type MinFreeSpace struct {
+	Type    MinFreeSpaceType
+	Bytes   uint64
+	Percent float32
+	Raw     string
+}
+
+// IsLow tells whether the free space is low or not.
+func (s MinFreeSpace) IsLow(freeBytes uint64, freePercent float32) (yes bool, desc string) {
+	switch s.Type {
+	case AsPercent:
+		yes = freePercent < s.Percent
+		op := IfElse(yes, "<", ">=")
+		return yes, fmt.Sprintf("disk free %.2f%% %s required %.2f%%", freePercent, op, s.Percent)
+	case AsBytes:
+		yes = freeBytes < s.Bytes
+		op := IfElse(yes, "<", ">=")
+		return yes, fmt.Sprintf("disk free %s %s required %s",
+			BytesToHumanReadable(freeBytes), op, BytesToHumanReadable(s.Bytes))
+	}
+
+	return false, ""
+}
+
+// String returns a string representation of MinFreeSpace.
+func (s MinFreeSpace) String() string {
+	switch s.Type {
+	case AsPercent:
+		return fmt.Sprintf("%.2f%%", s.Percent)
+	default:
+		return s.Raw
+	}
+}
+
+// MustParseMinFreeSpace parses comma-separated argument for min free space setting.
+// minFreeSpace has the high priority than minFreeSpacePercent if it is set.
+func MustParseMinFreeSpace(minFreeSpace string, minFreeSpacePercent string) (spaces []MinFreeSpace) {
+	ss := strings.Split(EmptyTo(minFreeSpace, minFreeSpacePercent), ",")
+	for _, freeString := range ss {
+		if vv, e := ParseMinFreeSpace(freeString); e == nil {
+			spaces = append(spaces, *vv)
+		} else {
+			glog.Fatalf("The value specified in -minFreeSpace not a valid value %s", freeString)
+		}
+	}
+
+	return spaces
+}
+
+var ErrMinFreeSpaceBadValue = errors.New("minFreeSpace is invalid")
+
+// ParseMinFreeSpace parses min free space expression s as percentage like 1,10 or human readable size like 10G
+func ParseMinFreeSpace(s string) (*MinFreeSpace, error) {
+	if percent, e := strconv.ParseFloat(s, 32); e == nil {
+		if percent < 0 || percent > 100 {
+			return nil, ErrMinFreeSpaceBadValue
+		}
+		return &MinFreeSpace{Type: AsPercent, Percent: float32(percent), Raw: s}, nil
+	}
+
+	if directSize, e := ParseBytes(s); e == nil {
+		if directSize <= 100 {
+			return nil, ErrMinFreeSpaceBadValue
+		}
+		return &MinFreeSpace{Type: AsBytes, Bytes: directSize, Raw: s}, nil
+	}
+
+	return nil, ErrMinFreeSpaceBadValue
+}