README
¶
Dig
A simple zero-dependency go package that provides a Ruby-like Hash.dig mechanism for map[string]any, which in YAML is refered to as "Mapping".
Usage
The provided dig.Mapping is handy when unmarshaling arbitrary YAML/JSON documents.
Example
package main
import (
"fmt"
"github.com/k0sproject/dig"
"gopkg.in/yaml.v2"
)
var yamlDoc = []byte(`---
i18n:
hello:
se: Hejsan
fi: Moi
world:
se: Värld
fi: Maailma
`)
func main() {
m := dig.Mapping{}
if err := yaml.Unmarshal(yamlDoc, &m); err != nil {
panic(err)
}
// You can use DigMapping to access a deeply nested map and set values.
// Any missing Mapping level in between will be created.
m.DigMapping("i18n", "hello")["es"] = "Hola"
m.DigMapping("i18n", "world")["es"] = "Mundo"
langs := []string{"fi", "se", "es"}
for _, l := range langs {
// You can use Dig to access a deeply nested value
greeting := m.Dig("i18n", "hello", l).(string)
// ..or DigString to avoid having to cast it to string.
target := m.DigString("i18n", "world", l)
fmt.Printf("%s, %s!\n", greeting, target)
}
}
Output:
Moi, Maailma!
Hejsan, Värld!
Hola, Mundo!
Documentation
¶
Overview ¶
Package dig provides a map[string]any Mapping type that has ruby-like "dig" functionality.
It can be used for example to access and manipulate arbitrary nested YAML/JSON structures.
Index ¶
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Mapping ¶
Mapping is a nested key-value map where the keys are strings and values are any. In Ruby it is called a Hash (with string keys), in YAML it's called a "mapping".
func (*Mapping) Dig ¶
Dig is a simplistic implementation of a Ruby-like Hash.dig functionality.
It returns a value from a (deeply) nested tree structure.
Example ¶
package main
import (
"fmt"
"github.com/k0sproject/dig"
)
func main() {
h := dig.Mapping{
"greeting": dig.Mapping{
"target": "world",
},
}
fmt.Println("Hello,", h.Dig("greeting", "target"))
}
Output: Hello, world
func (*Mapping) DigMapping ¶
DigMapping always returns a mapping, creating missing or overwriting non-mapping branches in between
Example ¶
package main
import (
"fmt"
"github.com/k0sproject/dig"
)
func main() {
h := dig.Mapping{}
h.DigMapping("greeting")["target"] = "world"
fmt.Println("Hello,", h.Dig("greeting", "target"))
}
Output: Hello, world
func (*Mapping) DigString ¶
DigString is like Dig but returns the value as string
Example ¶
package main
import (
"fmt"
"github.com/k0sproject/dig"
)
func main() {
h := dig.Mapping{}
h.DigMapping("greeting")["target"] = "world"
fmt.Println("Hello,", h.DigString("greeting", "target"), "!")
fmt.Println("Hello,", h.Dig("greeting", "non-existing"), "!")
fmt.Println("Hello,", h.DigString("greeting", "non-existing"), "!")
}
Output: Hello, world ! Hello, <nil> ! Hello, !
Source Files