YAML toolkit

Go library to deal with (not only) YAML documents.

Usage

Loading configuration file with defaults

given configuration file

config.yaml

---
listen_address: 0.0.0.0:8080
read_timeout: 15s

package main

import (
	"time"

	"github.com/rkosegi/yaml-toolkit/dom"
	"github.com/rkosegi/yaml-toolkit/fluent"
)

type Config struct {
	Address     string        `yaml:"listen_address"`
	ReadTimeout time.Duration `yaml:"read_timeout"`
}

var defConfig = &Config{
	Address: "0.0.0.0:8081",
}

func main() {
	cfg := fluent.NewConfigHelper[Config]().
		Add(defConfig).         // add defaults
		Load("config.yaml").    // override with values loaded from YAML document
		Result()                // get merged results

	// ... use cfg
}

Opening embedded YAML

example.yaml

---
kind: ConfigMap
metadata:
  name: cm1
  namespace: default
apiVersion: v1
data:
  application.yaml: |
    xyz: 456
    abc:
      def:
        leaf1: 123
        leaf2: Hello

code

package main

import (
    ydom "github.com/rkosegi/yaml-toolkit/dom"
    yk8s "github.com/rkosegi/yaml-toolkit/k8s"
)

func main() {
	d, err := yk8s.YamlDoc("example.yaml", "application.yaml")
	if err != nil {
		panic(err)
	}
	print (d.Document().Child("xyz").(ydom.Leaf).Value()) // 456
	d.Document().AddValue("another-key", ydom.LeafNode("789")) // add new child node
	err = d.Save()
	if err != nil {
		panic(err)
	}
}

Compute difference between 2 documents

Left	Right
left.yaml	right.yaml
--- root: sub1: leaf1: abc leaf2: 123 list: - 1 - 2	--- root: sub1: leaf1: def leaf3: 789 list: - 3

package main

import (
	"fmt"
	yta "github.com/rkosegi/yaml-toolkit/analytics"
	ytc "github.com/rkosegi/yaml-toolkit/common"
	ydiff "github.com/rkosegi/yaml-toolkit/diff"
)

func main() {
	dp := ytc.DefaultFileDecoderProvider(".yaml")
	ds := yta.NewDocumentSet()
	err := ds.AddDocumentFromFile("left.yaml", dp, yta.WithTags("left"))
	if err != nil {
		panic(err)
	}
	err = ds.AddDocumentFromFile("right.yaml", dp, yta.WithTags("right"))
	if err != nil {
		panic(err)
	}
	changes := ydiff.Diff(
		ds.TaggedSubset("right").Merged(),
		ds.TaggedSubset("left").Merged(),
	)
	fmt.Printf("All changes: %d\n", len(*changes))
	for _, change := range *changes {
		fmt.Printf("%s: %s => %v\n", change.Type, change.Path, change.Value)
	}
}

output:

All changes: 5
Delete: root.list => <nil>
Add: root.list[0] => 3
Change: root.sub1.leaf1 => abc
Delete: root.sub1.leaf2 => <nil>
Add: root.sub1.leaf3 => 789