128 lines
		
	
	
		
			4.4 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			128 lines
		
	
	
		
			4.4 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| # YAML <a href="https://www.npmjs.com/package/yaml"><img align="right" src="https://badge.fury.io/js/yaml.svg" title="npm package" /></a>
 | |
| 
 | |
| `yaml` is a JavaScript parser and stringifier for [YAML](http://yaml.org/), a human friendly data serialization standard. It supports both parsing and stringifying data using all versions of YAML, along with all common data schemas. As a particularly distinguishing feature, `yaml` fully supports reading and writing comments and blank lines in YAML documents.
 | |
| 
 | |
| The library is released under the ISC open source license, and the code is [available on GitHub](https://github.com/eemeli/yaml/). It has no external dependencies and runs on Node.js 6 and later, and in browsers from IE 11 upwards.
 | |
| 
 | |
| For the purposes of versioning, any changes that break any of the endpoints or APIs documented here will be considered semver-major breaking changes. Undocumented library internals may change between minor versions, and previous APIs may be deprecated (but not removed).
 | |
| 
 | |
| For more information, see the project's documentation site: [**eemeli.org/yaml/v1**](https://eemeli.org/yaml/v1/)
 | |
| 
 | |
| To install:
 | |
| 
 | |
| ```sh
 | |
| npm install yaml
 | |
| ```
 | |
| 
 | |
| **Note:** This is `yaml@1`. You may also be interested in the next version, currently available as [`yaml@next`](https://www.npmjs.com/package/yaml/v/next).
 | |
| 
 | |
| ## API Overview
 | |
| 
 | |
| The API provided by `yaml` has three layers, depending on how deep you need to go: [Parse & Stringify](https://eemeli.org/yaml/v1/#parse-amp-stringify), [Documents](https://eemeli.org/yaml/#documents), and the [CST Parser](https://eemeli.org/yaml/#cst-parser). The first has the simplest API and "just works", the second gets you all the bells and whistles supported by the library along with a decent [AST](https://eemeli.org/yaml/#content-nodes), and the third is the closest to YAML source, making it fast, raw, and crude.
 | |
| 
 | |
| ```js
 | |
| import YAML from 'yaml'
 | |
| // or
 | |
| const YAML = require('yaml')
 | |
| ```
 | |
| 
 | |
| ### Parse & Stringify
 | |
| 
 | |
| - [`YAML.parse(str, options): value`](https://eemeli.org/yaml/v1/#yaml-parse)
 | |
| - [`YAML.stringify(value, options): string`](https://eemeli.org/yaml/v1/#yaml-stringify)
 | |
| 
 | |
| ### YAML Documents
 | |
| 
 | |
| - [`YAML.createNode(value, wrapScalars, tag): Node`](https://eemeli.org/yaml/v1/#creating-nodes)
 | |
| - [`YAML.defaultOptions`](https://eemeli.org/yaml/v1/#options)
 | |
| - [`YAML.Document`](https://eemeli.org/yaml/v1/#yaml-documents)
 | |
|   - [`constructor(options)`](https://eemeli.org/yaml/v1/#creating-documents)
 | |
|   - [`defaults`](https://eemeli.org/yaml/v1/#options)
 | |
|   - [`#anchors`](https://eemeli.org/yaml/v1/#working-with-anchors)
 | |
|   - [`#contents`](https://eemeli.org/yaml/v1/#content-nodes)
 | |
|   - [`#errors`](https://eemeli.org/yaml/v1/#errors)
 | |
| - [`YAML.parseAllDocuments(str, options): YAML.Document[]`](https://eemeli.org/yaml/v1/#parsing-documents)
 | |
| - [`YAML.parseDocument(str, options): YAML.Document`](https://eemeli.org/yaml/v1/#parsing-documents)
 | |
| 
 | |
| ```js
 | |
| import { Pair, YAMLMap, YAMLSeq } from 'yaml/types'
 | |
| ```
 | |
| 
 | |
| - [`new Pair(key, value)`](https://eemeli.org/yaml/v1/#creating-nodes)
 | |
| - [`new YAMLMap()`](https://eemeli.org/yaml/v1/#creating-nodes)
 | |
| - [`new YAMLSeq()`](https://eemeli.org/yaml/v1/#creating-nodes)
 | |
| 
 | |
| ### CST Parser
 | |
| 
 | |
| ```js
 | |
| import parseCST from 'yaml/parse-cst'
 | |
| ```
 | |
| 
 | |
| - [`parseCST(str): CSTDocument[]`](https://eemeli.org/yaml/v1/#parsecst)
 | |
| - [`YAML.parseCST(str): CSTDocument[]`](https://eemeli.org/yaml/v1/#parsecst)
 | |
| 
 | |
| ## YAML.parse
 | |
| 
 | |
| ```yaml
 | |
| # file.yml
 | |
| YAML:
 | |
|   - A human-readable data serialization language
 | |
|   - https://en.wikipedia.org/wiki/YAML
 | |
| yaml:
 | |
|   - A complete JavaScript implementation
 | |
|   - https://www.npmjs.com/package/yaml
 | |
| ```
 | |
| 
 | |
| ```js
 | |
| import fs from 'fs'
 | |
| import YAML from 'yaml'
 | |
| 
 | |
| YAML.parse('3.14159')
 | |
| // 3.14159
 | |
| 
 | |
| YAML.parse('[ true, false, maybe, null ]\n')
 | |
| // [ true, false, 'maybe', null ]
 | |
| 
 | |
| const file = fs.readFileSync('./file.yml', 'utf8')
 | |
| YAML.parse(file)
 | |
| // { YAML:
 | |
| //   [ 'A human-readable data serialization language',
 | |
| //     'https://en.wikipedia.org/wiki/YAML' ],
 | |
| //   yaml:
 | |
| //   [ 'A complete JavaScript implementation',
 | |
| //     'https://www.npmjs.com/package/yaml' ] }
 | |
| ```
 | |
| 
 | |
| ## YAML.stringify
 | |
| 
 | |
| ```js
 | |
| import YAML from 'yaml'
 | |
| 
 | |
| YAML.stringify(3.14159)
 | |
| // '3.14159\n'
 | |
| 
 | |
| YAML.stringify([true, false, 'maybe', null])
 | |
| // `- true
 | |
| // - false
 | |
| // - maybe
 | |
| // - null
 | |
| // `
 | |
| 
 | |
| YAML.stringify({ number: 3, plain: 'string', block: 'two\nlines\n' })
 | |
| // `number: 3
 | |
| // plain: string
 | |
| // block: >
 | |
| //   two
 | |
| //
 | |
| //   lines
 | |
| // `
 | |
| ```
 | |
| 
 | |
| ---
 | |
| 
 | |
| Browser testing provided by:
 | |
| 
 | |
| <a href="https://www.browserstack.com/open-source">
 | |
| <img width=200 src="https://eemeli.org/yaml/images/browserstack.svg" />
 | |
| </a>
 |