ceph-csi/e2e/vendor/sigs.k8s.io/yaml/README.md
Niels de Vos f87d06ed85 build: move e2e dependencies into e2e/go.mod
Several packages are only used while running the e2e suite. These
packages are less important to update, as the they can not influence the
final executable that is part of the Ceph-CSI container-image.

By moving these dependencies out of the main Ceph-CSI go.mod, it is
easier to identify if a reported CVE affects Ceph-CSI, or only the
testing (like most of the Kubernetes CVEs).

Signed-off-by: Niels de Vos <ndevos@ibm.com>
2025-03-04 17:43:49 +01:00

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# YAML marshaling and unmarshaling support for Go
[![Build Status](https://travis-ci.org/kubernetes-sigs/yaml.svg)](https://travis-ci.org/kubernetes-sigs/yaml)
kubernetes-sigs/yaml is a permanent fork of [ghodss/yaml](https://github.com/ghodss/yaml).
## Introduction
A wrapper around [go-yaml](https://github.com/go-yaml/yaml) designed to enable a better way of handling YAML when marshaling to and from structs.
In short, this library first converts YAML to JSON using go-yaml and then uses `json.Marshal` and `json.Unmarshal` to convert to or from the struct. This means that it effectively reuses the JSON struct tags as well as the custom JSON methods `MarshalJSON` and `UnmarshalJSON` unlike go-yaml. For a detailed overview of the rationale behind this method, [see this blog post](http://web.archive.org/web/20190603050330/http://ghodss.com/2014/the-right-way-to-handle-yaml-in-golang/).
## Compatibility
This package uses [go-yaml](https://github.com/go-yaml/yaml) and therefore supports [everything go-yaml supports](https://github.com/go-yaml/yaml#compatibility).
## Caveats
**Caveat #1:** When using `yaml.Marshal` and `yaml.Unmarshal`, binary data should NOT be preceded with the `!!binary` YAML tag. If you do, go-yaml will convert the binary data from base64 to native binary data, which is not compatible with JSON. You can still use binary in your YAML files though - just store them without the `!!binary` tag and decode the base64 in your code (e.g. in the custom JSON methods `MarshalJSON` and `UnmarshalJSON`). This also has the benefit that your YAML and your JSON binary data will be decoded exactly the same way. As an example:
```
BAD:
exampleKey: !!binary gIGC
GOOD:
exampleKey: gIGC
... and decode the base64 data in your code.
```
**Caveat #2:** When using `YAMLToJSON` directly, maps with keys that are maps will result in an error since this is not supported by JSON. This error will occur in `Unmarshal` as well since you can't unmarshal map keys anyways since struct fields can't be keys.
## Installation and usage
To install, run:
```
$ go get sigs.k8s.io/yaml
```
And import using:
```
import "sigs.k8s.io/yaml"
```
Usage is very similar to the JSON library:
```go
package main
import (
"fmt"
"sigs.k8s.io/yaml"
)
type Person struct {
Name string `json:"name"` // Affects YAML field names too.
Age int `json:"age"`
}
func main() {
// Marshal a Person struct to YAML.
p := Person{"John", 30}
y, err := yaml.Marshal(p)
if err != nil {
fmt.Printf("err: %v\n", err)
return
}
fmt.Println(string(y))
/* Output:
age: 30
name: John
*/
// Unmarshal the YAML back into a Person struct.
var p2 Person
err = yaml.Unmarshal(y, &p2)
if err != nil {
fmt.Printf("err: %v\n", err)
return
}
fmt.Println(p2)
/* Output:
{John 30}
*/
}
```
`yaml.YAMLToJSON` and `yaml.JSONToYAML` methods are also available:
```go
package main
import (
"fmt"
"sigs.k8s.io/yaml"
)
func main() {
j := []byte(`{"name": "John", "age": 30}`)
y, err := yaml.JSONToYAML(j)
if err != nil {
fmt.Printf("err: %v\n", err)
return
}
fmt.Println(string(y))
/* Output:
age: 30
name: John
*/
j2, err := yaml.YAMLToJSON(y)
if err != nil {
fmt.Printf("err: %v\n", err)
return
}
fmt.Println(string(j2))
/* Output:
{"age":30,"name":"John"}
*/
}
```