check for new current tag

util/version/version.go

@@ -3,10 +3,13 @@ package version
 import (
 	"errors"
 	"fmt"
+	"sort"
 	"strings"
 
 	"github.com/Masterminds/semver"
 	"github.com/rusenask/keel/types"
+
+	log "github.com/Sirupsen/logrus"
 )
 
 // ErrVersionTagMissing - tag missing error
@@ -60,6 +63,47 @@ func GetImageNameAndVersion(name string) (string, *types.Version, error) {
 	return "", nil, ErrVersionTagMissing
 }
 
+// NewAvailable - takes version and current tags. Checks whether there is a new version in the list of tags
+// and returns it as well as newAvailable bool
+func NewAvailable(current string, tags []string) (newVersion string, newAvailable bool, err error) {
+
+	currentVersion, err := semver.NewVersion(current)
+	if err != nil {
+		return "", false, err
+	}
+
+	if len(tags) == 0 {
+		return "", false, nil
+	}
+
+	var vs []*semver.Version
+	for _, r := range tags {
+		v, err := semver.NewVersion(r)
+		if err != nil {
+			log.WithFields(log.Fields{
+				"error": err,
+				"tag":   r,
+			}).Error("failed to parse tag")
+			continue
+
+		}
+
+		vs = append(vs, v)
+	}
+
+	if len(vs) == 0 {
+		log.Error("no versions available")
+		return "", false, nil
+	}
+
+	sort.Sort(sort.Reverse(semver.Collection(vs)))
+
+	if currentVersion.LessThan(vs[0]) {
+		return vs[0].String(), true, nil
+	}
+	return "", false, nil
+}
+
 // ShouldUpdate - checks whether update is needed
 func ShouldUpdate(current *types.Version, new *types.Version, policy types.PolicyType) (bool, error) {
 	if policy == types.PolicyTypeForce {