containerd/reference/sort.go
Maksym Pavlenko e44335800e CRI: Move reference sorting to reference package
Signed-off-by: Maksym Pavlenko <pavlenko.maksym@gmail.com>
2022-05-26 12:52:36 -07:00

76 lines
1.8 KiB
Go

/*
Copyright The containerd Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package reference
import (
"sort"
"github.com/containerd/containerd/reference/docker"
)
// Sort sorts references by refRank then string comparison
func Sort(references []string) []string {
var prefs []docker.Reference
var bad []string
for _, ref := range references {
pref, err := docker.ParseAnyReference(ref)
if err != nil {
bad = append(bad, ref)
} else {
prefs = append(prefs, pref)
}
}
sort.Slice(prefs, func(a, b int) bool {
ar := refRank(prefs[a])
br := refRank(prefs[b])
if ar == br {
return prefs[a].String() < prefs[b].String()
}
return ar < br
})
sort.Strings(bad)
var refs []string
for _, pref := range prefs {
refs = append(refs, pref.String())
}
return append(refs, bad...)
}
// refRank ranks precedence for reference type, preferring higher information references
// 1. Name + Tag + Digest
// 2. Name + Tag
// 3. Name + Digest
// 4. Name
// 5. Digest
// 6. Parse error
func refRank(ref docker.Reference) uint8 {
if _, ok := ref.(docker.Named); ok {
if _, ok = ref.(docker.Tagged); ok {
if _, ok = ref.(docker.Digested); ok {
return 1
}
return 2
}
if _, ok = ref.(docker.Digested); ok {
return 3
}
return 4
}
return 5
}