mount: quota for one mounted collection

related to https://github.com/seaweedfs/seaweedfs-csi-driver/issues/48

weed/mount/weedfs_quota.go

@@ -0,0 +1,53 @@
+package mount
+
+import (
+	"context"
+	"fmt"
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
+	"time"
+)
+
+func (wfs *WFS) loopCheckQuota() {
+
+	if wfs.option.Quota <= 0 {
+		return
+	}
+
+	for {
+
+		err := wfs.WithFilerClient(false, func(client filer_pb.SeaweedFilerClient) error {
+
+			request := &filer_pb.StatisticsRequest{
+				Collection:  wfs.option.Collection,
+				Replication: wfs.option.Replication,
+				Ttl:         fmt.Sprintf("%ds", wfs.option.TtlSec),
+				DiskType:    string(wfs.option.DiskType),
+			}
+
+			resp, err := client.Statistics(context.Background(), request)
+			if err != nil {
+				glog.V(0).Infof("reading quota usage %v: %v", request, err)
+				return err
+			}
+			glog.V(4).Infof("read quota usage: %+v", resp)
+
+			isOverQuota := int64(resp.UsedSize) > wfs.option.Quota
+			if isOverQuota && !wfs.IsOverQuota {
+				glog.Warningf("Quota Exceeded! quota:%d used:%d", wfs.option.Quota, resp.UsedSize)
+			} else if !isOverQuota && wfs.IsOverQuota {
+				glog.Warningf("Within quota limit! quota:%d used:%d", wfs.option.Quota, resp.UsedSize)
+			}
+			wfs.IsOverQuota = isOverQuota
+
+			return nil
+		})
+
+		if err != nil {
+			glog.Warningf("read quota usage: %v", err)
+		}
+
+		time.Sleep(61 * time.Second)
+	}
+
+}