support for collections!

go/topology/collection.go

@@ -0,0 +1,38 @@
+package topology
+
+import (
+	"code.google.com/p/weed-fs/go/glog"
+	"code.google.com/p/weed-fs/go/storage"
+)
+
+type Collection struct {
+	Name                     string
+	volumeSizeLimit          uint64
+	replicaType2VolumeLayout []*VolumeLayout
+}
+
+func NewCollection(name string, volumeSizeLimit uint64) *Collection {
+	c := &Collection{Name: name, volumeSizeLimit: volumeSizeLimit}
+	c.replicaType2VolumeLayout = make([]*VolumeLayout, storage.LengthRelicationType)
+	return c
+}
+
+func (c *Collection) GetOrCreateVolumeLayout(repType storage.ReplicationType) *VolumeLayout {
+	replicationTypeIndex := repType.GetReplicationLevelIndex()
+	if c.replicaType2VolumeLayout[replicationTypeIndex] == nil {
+		glog.V(0).Infoln("collection", c.Name, "adding replication type", repType)
+		c.replicaType2VolumeLayout[replicationTypeIndex] = NewVolumeLayout(repType, c.volumeSizeLimit)
+	}
+	return c.replicaType2VolumeLayout[replicationTypeIndex]
+}
+
+func (c *Collection) Lookup(vid storage.VolumeId) []*DataNode {
+	for _, vl := range c.replicaType2VolumeLayout {
+		if vl != nil {
+			if list := vl.Lookup(vid); list != nil {
+				return list
+			}
+		}
+	}
+	return nil
+}