kubernetes/vendor/sigs.k8s.io/kustomize/api/image/image.go

67 lines
1.8 KiB
Go

// Copyright 2020 The Kubernetes Authors.
// SPDX-License-Identifier: Apache-2.0
package image
import (
"regexp"
"strings"
)
// IsImageMatched returns true if the value of t is identical to the
// image name in the full image name and tag as given by s.
func IsImageMatched(s, t string) bool {
// Tag values are limited to [a-zA-Z0-9_.{}-].
// Some tools like Bazel rules_k8s allow tag patterns with {} characters.
// More info: https://github.com/bazelbuild/rules_k8s/pull/423
pattern, _ := regexp.Compile("^" + t + "(:[a-zA-Z0-9_.{}-]*)?(@sha256:[a-zA-Z0-9_.{}-]*)?$")
return pattern.MatchString(s)
}
// Split separates and returns the name and tag parts
// from the image string using either colon `:` or at `@` separators.
// image reference pattern: [[host[:port]/]component/]component[:tag][@digest]
func Split(imageName string) (name string, tag string, digest string) {
// check if image name contains a domain
// if domain is present, ignore domain and check for `:`
searchName := imageName
slashIndex := strings.Index(imageName, "/")
if slashIndex > 0 {
searchName = imageName[slashIndex:]
} else {
slashIndex = 0
}
id := strings.Index(searchName, "@")
ic := strings.Index(searchName, ":")
// no tag or digest
if ic < 0 && id < 0 {
return imageName, "", ""
}
// digest only
if id >= 0 && (id < ic || ic < 0) {
id += slashIndex
name = imageName[:id]
digest = strings.TrimPrefix(imageName[id:], "@")
return name, "", digest
}
// tag and digest
if id >= 0 && ic >= 0 {
id += slashIndex
ic += slashIndex
name = imageName[:ic]
tag = strings.TrimPrefix(imageName[ic:id], ":")
digest = strings.TrimPrefix(imageName[id:], "@")
return name, tag, digest
}
// tag only
ic += slashIndex
name = imageName[:ic]
tag = strings.TrimPrefix(imageName[ic:], ":")
return name, tag, ""
}