| # YAML support for the Go language |
| |
| Introduction |
| ------------ |
| |
| The yaml package enables Go programs to comfortably encode and decode YAML |
| values. It was developed within [Canonical](https://www.canonical.com) as |
| part of the [juju](https://juju.ubuntu.com) project, and is based on a |
| pure Go port of the well-known [libyaml](http://pyyaml.org/wiki/LibYAML) |
| C library to parse and generate YAML data quickly and reliably. |
| |
| Compatibility |
| ------------- |
| |
| The yaml package is almost compatible with YAML 1.1, including support for |
| anchors, tags, etc. There are still a few missing bits, such as document |
| merging, base-60 floats (huh?), and multi-document unmarshalling. These |
| features are not hard to add, and will be introduced as necessary. |
| |
| Installation and usage |
| ---------------------- |
| |
| The import path for the package is *gopkg.in/v1/yaml*. |
| |
| To install it, run: |
| |
| go get gopkg.in/v1/yaml |
| |
| API documentation |
| ----------------- |
| |
| If opened in a browser, the import path itself leads to the API documentation: |
| |
| * [https://gopkg.in/v1/yaml](https://gopkg.in/v1/yaml) |
| |
| API stability |
| ------------- |
| |
| The package API for yaml v1 will remain stable as described in [gopkg.in](https://gopkg.in). |
| |
| |
| License |
| ------- |
| |
| The yaml package is licensed under the LGPL with an exception that allows it to be linked statically. Please see the LICENSE file for details. |
| |
| |
| Example |
| ------- |
| |
| ```Go |
| package main |
| |
| import ( |
| "fmt" |
| "log" |
| |
| "gopkg.in/v1/yaml" |
| ) |
| |
| var data = ` |
| a: Easy! |
| b: |
| c: 2 |
| d: [3, 4] |
| ` |
| |
| type T struct { |
| A string |
| B struct{C int; D []int ",flow"} |
| } |
| |
| func main() { |
| t := T{} |
| |
| err := yaml.Unmarshal([]byte(data), &t) |
| if err != nil { |
| log.Fatalf("error: %v", err) |
| } |
| fmt.Printf("--- t:\n%v\n\n", t) |
| |
| d, err := yaml.Marshal(&t) |
| if err != nil { |
| log.Fatalf("error: %v", err) |
| } |
| fmt.Printf("--- t dump:\n%s\n\n", string(d)) |
| |
| m := make(map[interface{}]interface{}) |
| |
| err = yaml.Unmarshal([]byte(data), &m) |
| if err != nil { |
| log.Fatalf("error: %v", err) |
| } |
| fmt.Printf("--- m:\n%v\n\n", m) |
| |
| d, err = yaml.Marshal(&m) |
| if err != nil { |
| log.Fatalf("error: %v", err) |
| } |
| fmt.Printf("--- m dump:\n%s\n\n", string(d)) |
| } |
| ``` |
| |
| This example will generate the following output: |
| |
| ``` |
| --- t: |
| {Easy! {2 [3 4]}} |
| |
| --- t dump: |
| a: Easy! |
| b: |
| c: 2 |
| d: [3, 4] |
| |
| |
| --- m: |
| map[a:Easy! b:map[c:2 d:[3 4]]] |
| |
| --- m dump: |
| a: Easy! |
| b: |
| c: 2 |
| d: |
| - 3 |
| - 4 |
| ``` |
| |