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

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## 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/toml-lang/toml
Compatible with TOML version
[v0.4.0](https://github.com/toml-lang/toml/blob/master/versions/en/toml-v0.4.0.md)
Documentation: https://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://travis-ci.org/BurntSushi/toml.svg?branch=master)](https://travis-ci.org/BurntSushi/toml) [![GoDoc](https://godoc.org/github.com/BurntSushi/toml?status.svg)](https://godoc.org/github.com/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}`.