Move command line snapshot sorting to common snapshot code

cmd/snapshot_list.go

@@ -4,49 +4,8 @@ import (
 	"fmt"
 	"github.com/smira/aptly/deb"
 	"github.com/smira/commander"
-	"sort"
 )
 
-// Snapshot sorting methods
-const (
-	SortName = iota
-	SortTime
-)
-
-type snapshotListToSort struct {
-	list       []*deb.Snapshot
-	sortMethod int
-}
-
-func parseSortMethod(sortMethod string) (int, error) {
-	switch sortMethod {
-	case "time", "Time":
-		return SortTime, nil
-	case "name", "Name":
-		return SortName, nil
-	}
-
-	return -1, fmt.Errorf("sorting method \"%s\" unknown", sortMethod)
-}
-
-func (s snapshotListToSort) Swap(i, j int) {
-	s.list[i], s.list[j] = s.list[j], s.list[i]
-}
-
-func (s snapshotListToSort) Less(i, j int) bool {
-	switch s.sortMethod {
-	case SortName:
-		return s.list[i].Name < s.list[j].Name
-	case SortTime:
-		return s.list[i].CreatedAt.Before(s.list[j].CreatedAt)
-	}
-	panic("unknown sort method")
-}
-
-func (s snapshotListToSort) Len() int {
-	return len(s.list)
-}
-
 func aptlySnapshotList(cmd *commander.Command, args []string) error {
 	var err error
 	if len(args) != 0 {
@@ -57,44 +16,30 @@ func aptlySnapshotList(cmd *commander.Command, args []string) error {
 	raw := cmd.Flag.Lookup("raw").Value.Get().(bool)
 	sortMethodString := cmd.Flag.Lookup("sort").Value.Get().(string)
 
-	snapshotsToSort := &snapshotListToSort{}
-	snapshotsToSort.list = make([]*deb.Snapshot, context.CollectionFactory().SnapshotCollection().Len())
-	snapshotsToSort.sortMethod, err = parseSortMethod(sortMethodString)
-	if err != nil {
-		return err
-	}
-
-	i := 0
-	context.CollectionFactory().SnapshotCollection().ForEach(func(snapshot *deb.Snapshot) error {
-		snapshotsToSort.list[i] = snapshot
-		i++
-
-		return nil
-	})
-
-	context.CloseDatabase()
-
-	sort.Sort(snapshotsToSort)
+	collection := context.CollectionFactory().SnapshotCollection()
+	collection.Sort(sortMethodString)
 
 	if raw {
-		for _, snapshot := range snapshotsToSort.list {
+		collection.ForEach(func(snapshot *deb.Snapshot) error {
 			fmt.Printf("%s\n", snapshot.Name)
-		}
+			return nil
+		})
 	} else {
-		if len(snapshotsToSort.list) > 0 {
+		if collection.Len() > 0 {
 			fmt.Printf("List of snapshots:\n")
 
-			for _, snapshot := range snapshotsToSort.list {
+			collection.ForEach(func(snapshot *deb.Snapshot) error {
 				fmt.Printf(" * %s\n", snapshot.String())
-			}
+				return nil
+			})
 
 			fmt.Printf("\nTo get more information about snapshot, run `aptly snapshot show <name>`.\n")
 		} else {
 			fmt.Printf("\nNo snapshots found, create one with `aptly snapshot create...`.\n")
 		}
 	}
-	return err
 
+	return err
 }
 
 func makeCmdSnapshotList() *commander.Command {