Unmarshaling an invalid YAML is not throwing an error

[kishorviswanathan]

Summary

Unmarshaling an invalid YAML with yaml.Unmarshal populates struct with invalid data rather than returning an error.

Example

package main

import (
	"fmt"
	"sigs.k8s.io/yaml"
)

const (
	invalidYAML = `
  test:
test1: hello
`
)

type yamlType struct {
	Test  string `yaml:"test"`
	Test1 string `yaml:"test1"`
}

func main() {
	var data yamlType
	err := yaml.Unmarshal([]byte(invalidYAML), &data)
	if err != nil {
		fmt.Printf("Error %e", err)
	}
	fmt.Printf("data: %+v\n", data)
}

Output:

data: map[test:<nil>]

Expected output

The function should throw an error since the YAML is not valid.

Additional Information

• Related issues: Builtin yaml.is_valid returns valid for invalid YAML open-policy-agent/opa#6854

[dims]

try UnmarshalStrict

/close

[k8s-ci-robot]

@dims: Closing this issue.

In response to this:

try UnmarshalStrict

/close

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.

[kishorviswanathan]

Makes no difference if this is what you meant.

package main

import (
	"fmt"

	"sigs.k8s.io/yaml"
)

const (
	invalidYAML = `
  test:
test1: hello
`
)

type yamlType struct {
	Test  string `yaml:"test"`
	Test1 string `yaml:"test1"`
}

func main() {
	var data1 interface{}
	err := yaml.UnmarshalStrict([]byte(invalidYAML), &data1)
	if err != nil {
		fmt.Printf("Error1 %e", err)
	}

	fmt.Printf("data1: %+v\n", data1)

	var data2 yamlType
	err = yaml.UnmarshalStrict([]byte(invalidYAML), &data2)
	if err != nil {
		fmt.Printf("Error2 %e", err)
	}
	fmt.Printf("data2: %+v\n", data2)
}

Output:

data1: map[test:<nil>]
data2: {Test: Test1:}

[kishorviswanathan]

@dims I am not sure if this issue should remain closed as I was able to reproduce the bug with UnmarshalStrict as well. I don't have permission to reopen it.

[anderseknert]

I too would want to know more about this behavior. Thanks for looking into it @kishorviswanathan 👍

[gusega]

Hi all, any update on this?

[Seraphyno]

Hi, I'm also following this thread, currently blocked by this upstream issue as I'm using OPA which relies