containerd/vendor/github.com/BurntSushi/toml/README.md

## TOML parser and encoder for Go with reflection

TOML stands for Tom's Obvious, Minimal Language. This Go package provides a
reflection interface similar to Go's standard library `json` and `xml` 
packages. This package also supports the `encoding.TextUnmarshaler` and
`encoding.TextMarshaler` interfaces so that you can define custom data 
representations. (There is an example of this below.)

Spec: https://github.com/mojombo/toml

Compatible with TOML version
[v0.2.0](https://github.com/toml-lang/toml/blob/master/versions/en/toml-v0.2.0.md)

Documentation: http://godoc.org/github.com/BurntSushi/toml

Installation:

```bash
go get github.com/BurntSushi/toml
```

Try the toml validator:

```bash
go get github.com/BurntSushi/toml/cmd/tomlv
tomlv some-toml-file.toml
```

[![Build status](https://api.travis-ci.org/BurntSushi/toml.png)](https://travis-ci.org/BurntSushi/toml)


### Testing

This package passes all tests in
[toml-test](https://github.com/BurntSushi/toml-test) for both the decoder
and the encoder.

### Examples

This package works similarly to how the Go standard library handles `XML`
and `JSON`. Namely, data is loaded into Go values via reflection.

For the simplest example, consider some TOML file as just a list of keys
and values:

```toml
Age = 25
Cats = [ "Cauchy", "Plato" ]
Pi = 3.14
Perfection = [ 6, 28, 496, 8128 ]
DOB = 1987-07-05T05:45:00Z
```

Which could be defined in Go as:

```go
type Config struct {
  Age int
  Cats []string
  Pi float64
  Perfection []int
  DOB time.Time // requires `import time`
}
```

And then decoded with:

```go
var conf Config
if _, err := toml.Decode(tomlData, &conf); err != nil {
  // handle error
}
```

You can also use struct tags if your struct field name doesn't map to a TOML
key value directly:

```toml
some_key_NAME = "wat"
```

```go
type TOML struct {
  ObscureKey string `toml:"some_key_NAME"`
}
```

### Using the `encoding.TextUnmarshaler` interface

Here's an example that automatically parses duration strings into 
`time.Duration` values:

```toml
[[song]]
name = "Thunder Road"
duration = "4m49s"

[[song]]
name = "Stairway to Heaven"
duration = "8m03s"
```

Which can be decoded with:

```go
type song struct {
  Name     string
  Duration duration
}
type songs struct {
  Song []song
}
var favorites songs
if _, err := toml.Decode(blob, &favorites); err != nil {
  log.Fatal(err)
}

for _, s := range favorites.Song {
  fmt.Printf("%s (%s)\n", s.Name, s.Duration)
}
```

And you'll also need a `duration` type that satisfies the 
`encoding.TextUnmarshaler` interface:

```go
type duration struct {
	time.Duration
}

func (d *duration) UnmarshalText(text []byte) error {
	var err error
	d.Duration, err = time.ParseDuration(string(text))
	return err
}
```

### More complex usage

Here's an example of how to load the example from the official spec page:

```toml
# This is a TOML document. Boom.

title = "TOML Example"

[owner]
name = "Tom Preston-Werner"
organization = "GitHub"
bio = "GitHub Cofounder & CEO\nLikes tater tots and beer."
dob = 1979-05-27T07:32:00Z # First class dates? Why not?

[database]
server = "192.168.1.1"
ports = [ 8001, 8001, 8002 ]
connection_max = 5000
enabled = true

[servers]

  # You can indent as you please. Tabs or spaces. TOML don't care.
  [servers.alpha]
  ip = "10.0.0.1"
  dc = "eqdc10"

  [servers.beta]
  ip = "10.0.0.2"
  dc = "eqdc10"

[clients]
data = [ ["gamma", "delta"], [1, 2] ] # just an update to make sure parsers support it

# Line breaks are OK when inside arrays
hosts = [
  "alpha",
  "omega"
]
```

And the corresponding Go types are:

```go
type tomlConfig struct {
	Title string
	Owner ownerInfo
	DB database `toml:"database"`
	Servers map[string]server
	Clients clients
}

type ownerInfo struct {
	Name string
	Org string `toml:"organization"`
	Bio string
	DOB time.Time
}

type database struct {
	Server string
	Ports []int
	ConnMax int `toml:"connection_max"`
	Enabled bool
}

type server struct {
	IP string
	DC string
}

type clients struct {
	Data [][]interface{}
	Hosts []string
}
```

Note that a case insensitive match will be tried if an exact match can't be
found.

A working example of the above can be found in `_examples/example.{go,toml}`.