Yams: A Sweet and Swifty YAML Parser

Yams

A sweet and swifty YAML parser built on LibYAML.

Yams

Installation

Building Yams requires Xcode 12.5+ or a Swift 5.4+ toolchain with the Swift Package Manager or CMake and Ninja.

CMake

CMake 3.17.2 or newer is required, along with Ninja 1.9.0 or newer.

When building for non-Apple platforms:

cmake -B /path/to/build -G Ninja -S /path/to/yams -DCMAKE_BUILD_TYPE=Release -DFoundation_DIR=/path/to/foundation/build/cmake/modules
cmake --build /path/to/build

To build for Apple platforms (macOS, iOS, tvOS, watchOS), there is no need to spearately build Foundation because it is included as part of the SDK:

cmake -B /path/to/build -G Ninja -S /path/to/yams -DCMAKE_BUILD_TYPE=Release
cmake --build /path/to/build

Swift Package Manager

Add .package(url: "https://github.com/jpsim/Yams.git", from: "5.0.1") to your Package.swift file's dependencies.

CocoaPods

Add pod 'Yams' to your Podfile.

Carthage

Add github "jpsim/Yams" to your Cartfile.

Bazel

In your WORKSPACE file

YAMS_GIT_SHA = "SOME_SHA"
http_archive(
    name = "com_github_jpsim_yams",
    urls = [
        "https://github.com/jpsim/Yams/archive/%s.zip" % YAMS_GIT_SHA,
    ],
    strip_prefix = "Yams-%s" % YAMS_GIT_SHA,
)

Usage

Yams has three groups of conversion APIs: one for use with Codable types, another for Swift Standard Library types, and a third one for a Yams-native representation.

`Codable` types

Codable is an encoding & decoding strategy introduced in Swift 4 enabling easy conversion between YAML and other Encoders like JSONEncoder and PropertyListEncoder.
Lowest computational overhead, equivalent to Yams.Node.
Encoding: YAMLEncoder.encode(_:) Produces a YAML String from an instance of type conforming to Encodable.
Decoding: YAMLDecoder.decode(_:from:) Decodes an instance of type conforming to Decodable from YAML String or Data.

import Foundation
import Yams

struct S: Codable {
    var p: String
}

let s = S(p: "test")
let encoder = YAMLEncoder()
let encodedYAML = try encoder.encode(s)
encodedYAML == """
p: test

"""
let decoder = YAMLDecoder()
let decoded = try decoder.decode(S.self, from: encodedYAML)
s.p == decoded.p

Swift Standard Library types

The type of Swift Standard Library is inferred from the contents of the internal Yams.Node representation by matching regular expressions.
This method has the largest computational overhead When decoding YAML, because the type inference of all objects is done up-front.
It may be easier to use in such a way as to handle objects created from JSONSerialization or if the input is already standard library types (Any, Dictionary, Array, etc.).
Encoding: Yams.dump(object:) Produces a YAML String from an instance of Swift Standard Library types.
Decoding: Yams.load(yaml:) Produces an instance of Swift Standard Library types as Any from YAML String.

// [String: Any]
let dictionary: [String: Any] = ["key": "value"]
let mapYAML: String = try Yams.dump(object: dictionary)
mapYAML == """
key: value

"""
let loadedDictionary = try Yams.load(yaml: mapYAML) as? [String: Any]

// [Any]
let array: [Int] = [1, 2, 3]
let sequenceYAML: String = try Yams.dump(object: array)
sequenceYAML == """
- 1
- 2
- 3

"""
let loadedArray: [Int]? = try Yams.load(yaml: sequenceYAML) as? [Int]

// Any
let string = "string"
let scalarYAML: String = try Yams.dump(object: string)
scalarYAML == """
string

"""
let loadedString: String? = try Yams.load(yaml: scalarYAML) as? String

`Yams.Node`

Yams' native model representing Nodes of YAML which provides all functions such as detection and customization of the YAML format.
Depending on how it is used, computational overhead can be minimized.
Encoding: Yams.serialize(node:) Produces a YAML String from an instance of Node.
Decoding Yams.compose(yaml:) Produces an instance of Node from YAML String.

var map: Yams.Node = [
    "array": [
        1, 2, 3
    ]
]
map.mapping?.style = .flow
map["array"]?.sequence?.style = .flow
let yaml = try Yams.serialize(node: map)
yaml == """
{array: [1, 2, 3]}

"""
let node = try Yams.compose(yaml: yaml)
map == node

Integrating with Combine

When Apple's Combine framework is available, YAMLDecoder conforms to the TopLevelDecoder protocol, which allows it to be used with the decode(type:decoder:) operator:

import Combine
import Foundation
import Yams

func fetchBook(from url: URL) -> AnyPublisher<Book, Error> {
    URLSession.shared.dataTaskPublisher(for: url)
        .map(\.data)
        .decode(type: Book.self, decoder: YAMLDecoder())
        .eraseToAnyPublisher()
}

Download Details:

Author: jpsim
Source Code: https://github.com/jpsim/Yams
License: MIT license

#swift #macos #linux #yaml #ios

Yams: A Sweet and Swifty YAML Parser

Yams

A sweet and swifty YAML parser built on LibYAML.

Yams

Installation

Building Yams requires Xcode 12.5+ or a Swift 5.4+ toolchain with the Swift Package Manager or CMake and Ninja.

CMake

CMake 3.17.2 or newer is required, along with Ninja 1.9.0 or newer.

When building for non-Apple platforms:

cmake -B /path/to/build -G Ninja -S /path/to/yams -DCMAKE_BUILD_TYPE=Release -DFoundation_DIR=/path/to/foundation/build/cmake/modules
cmake --build /path/to/build

To build for Apple platforms (macOS, iOS, tvOS, watchOS), there is no need to spearately build Foundation because it is included as part of the SDK:

cmake -B /path/to/build -G Ninja -S /path/to/yams -DCMAKE_BUILD_TYPE=Release
cmake --build /path/to/build

Swift Package Manager

Add .package(url: "https://github.com/jpsim/Yams.git", from: "5.0.1") to your Package.swift file's dependencies.

CocoaPods

Add pod 'Yams' to your Podfile.

Carthage

Add github "jpsim/Yams" to your Cartfile.

Bazel

In your WORKSPACE file

YAMS_GIT_SHA = "SOME_SHA"
http_archive(
    name = "com_github_jpsim_yams",
    urls = [
        "https://github.com/jpsim/Yams/archive/%s.zip" % YAMS_GIT_SHA,
    ],
    strip_prefix = "Yams-%s" % YAMS_GIT_SHA,
)

Usage

Yams has three groups of conversion APIs: one for use with Codable types, another for Swift Standard Library types, and a third one for a Yams-native representation.

`Codable` types

Codable is an encoding & decoding strategy introduced in Swift 4 enabling easy conversion between YAML and other Encoders like JSONEncoder and PropertyListEncoder.
Lowest computational overhead, equivalent to Yams.Node.
Encoding: YAMLEncoder.encode(_:) Produces a YAML String from an instance of type conforming to Encodable.
Decoding: YAMLDecoder.decode(_:from:) Decodes an instance of type conforming to Decodable from YAML String or Data.

import Foundation
import Yams

struct S: Codable {
    var p: String
}

let s = S(p: "test")
let encoder = YAMLEncoder()
let encodedYAML = try encoder.encode(s)
encodedYAML == """
p: test

"""
let decoder = YAMLDecoder()
let decoded = try decoder.decode(S.self, from: encodedYAML)
s.p == decoded.p

Swift Standard Library types

The type of Swift Standard Library is inferred from the contents of the internal Yams.Node representation by matching regular expressions.
This method has the largest computational overhead When decoding YAML, because the type inference of all objects is done up-front.
It may be easier to use in such a way as to handle objects created from JSONSerialization or if the input is already standard library types (Any, Dictionary, Array, etc.).
Encoding: Yams.dump(object:) Produces a YAML String from an instance of Swift Standard Library types.
Decoding: Yams.load(yaml:) Produces an instance of Swift Standard Library types as Any from YAML String.

// [String: Any]
let dictionary: [String: Any] = ["key": "value"]
let mapYAML: String = try Yams.dump(object: dictionary)
mapYAML == """
key: value

"""
let loadedDictionary = try Yams.load(yaml: mapYAML) as? [String: Any]

// [Any]
let array: [Int] = [1, 2, 3]
let sequenceYAML: String = try Yams.dump(object: array)
sequenceYAML == """
- 1
- 2
- 3

"""
let loadedArray: [Int]? = try Yams.load(yaml: sequenceYAML) as? [Int]

// Any
let string = "string"
let scalarYAML: String = try Yams.dump(object: string)
scalarYAML == """
string

"""
let loadedString: String? = try Yams.load(yaml: scalarYAML) as? String

`Yams.Node`

Yams' native model representing Nodes of YAML which provides all functions such as detection and customization of the YAML format.
Depending on how it is used, computational overhead can be minimized.
Encoding: Yams.serialize(node:) Produces a YAML String from an instance of Node.
Decoding Yams.compose(yaml:) Produces an instance of Node from YAML String.

var map: Yams.Node = [
    "array": [
        1, 2, 3
    ]
]
map.mapping?.style = .flow
map["array"]?.sequence?.style = .flow
let yaml = try Yams.serialize(node: map)
yaml == """
{array: [1, 2, 3]}

"""
let node = try Yams.compose(yaml: yaml)
map == node

Integrating with Combine

When Apple's Combine framework is available, YAMLDecoder conforms to the TopLevelDecoder protocol, which allows it to be used with the decode(type:decoder:) operator:

import Combine
import Foundation
import Yams

func fetchBook(from url: URL) -> AnyPublisher<Book, Error> {
    URLSession.shared.dataTaskPublisher(for: url)
        .map(\.data)
        .decode(type: Book.self, decoder: YAMLDecoder())
        .eraseToAnyPublisher()
}

Download Details:

Author: jpsim
Source Code: https://github.com/jpsim/Yams
License: MIT license

#swift #macos #linux #yaml #ios

Jarvis Maggio

1661992800

Yams: A Sweet and Swifty YAML Parser

Yams

A sweet and swifty YAML parser built on LibYAML.

Installation

Building Yams requires Xcode 12.5+ or a Swift 5.4+ toolchain with the Swift Package Manager or CMake and Ninja.

CMake

CMake 3.17.2 or newer is required, along with Ninja 1.9.0 or newer.

When building for non-Apple platforms:

cmake -B /path/to/build -G Ninja -S /path/to/yams -DCMAKE_BUILD_TYPE=Release -DFoundation_DIR=/path/to/foundation/build/cmake/modules
cmake --build /path/to/build

To build for Apple platforms (macOS, iOS, tvOS, watchOS), there is no need to spearately build Foundation because it is included as part of the SDK:

cmake -B /path/to/build -G Ninja -S /path/to/yams -DCMAKE_BUILD_TYPE=Release
cmake --build /path/to/build

Swift Package Manager

Add .package(url: "https://github.com/jpsim/Yams.git", from: "5.0.1") to your Package.swift file's dependencies.

CocoaPods

Add pod 'Yams' to your Podfile.

Carthage

Add github "jpsim/Yams" to your Cartfile.

Bazel

In your WORKSPACE file

YAMS_GIT_SHA = "SOME_SHA"
http_archive(
    name = "com_github_jpsim_yams",
    urls = [
        "https://github.com/jpsim/Yams/archive/%s.zip" % YAMS_GIT_SHA,
    ],
    strip_prefix = "Yams-%s" % YAMS_GIT_SHA,
)

Usage

Yams has three groups of conversion APIs: one for use with Codable types, another for Swift Standard Library types, and a third one for a Yams-native representation.

`Codable` types

Codable is an encoding & decoding strategy introduced in Swift 4 enabling easy conversion between YAML and other Encoders like JSONEncoder and PropertyListEncoder.
Lowest computational overhead, equivalent to Yams.Node.
Encoding: YAMLEncoder.encode(_:) Produces a YAML String from an instance of type conforming to Encodable.
Decoding: YAMLDecoder.decode(_:from:) Decodes an instance of type conforming to Decodable from YAML String or Data.

import Foundation
import Yams

struct S: Codable {
    var p: String
}

let s = S(p: "test")
let encoder = YAMLEncoder()
let encodedYAML = try encoder.encode(s)
encodedYAML == """
p: test

"""
let decoder = YAMLDecoder()
let decoded = try decoder.decode(S.self, from: encodedYAML)
s.p == decoded.p

Swift Standard Library types

The type of Swift Standard Library is inferred from the contents of the internal Yams.Node representation by matching regular expressions.
This method has the largest computational overhead When decoding YAML, because the type inference of all objects is done up-front.
It may be easier to use in such a way as to handle objects created from JSONSerialization or if the input is already standard library types (Any, Dictionary, Array, etc.).
Encoding: Yams.dump(object:) Produces a YAML String from an instance of Swift Standard Library types.
Decoding: Yams.load(yaml:) Produces an instance of Swift Standard Library types as Any from YAML String.

// [String: Any]
let dictionary: [String: Any] = ["key": "value"]
let mapYAML: String = try Yams.dump(object: dictionary)
mapYAML == """
key: value

"""
let loadedDictionary = try Yams.load(yaml: mapYAML) as? [String: Any]

// [Any]
let array: [Int] = [1, 2, 3]
let sequenceYAML: String = try Yams.dump(object: array)
sequenceYAML == """
- 1
- 2
- 3

"""
let loadedArray: [Int]? = try Yams.load(yaml: sequenceYAML) as? [Int]

// Any
let string = "string"
let scalarYAML: String = try Yams.dump(object: string)
scalarYAML == """
string

"""
let loadedString: String? = try Yams.load(yaml: scalarYAML) as? String

`Yams.Node`

Yams' native model representing Nodes of YAML which provides all functions such as detection and customization of the YAML format.
Depending on how it is used, computational overhead can be minimized.
Encoding: Yams.serialize(node:) Produces a YAML String from an instance of Node.
Decoding Yams.compose(yaml:) Produces an instance of Node from YAML String.

var map: Yams.Node = [
    "array": [
        1, 2, 3
    ]
]
map.mapping?.style = .flow
map["array"]?.sequence?.style = .flow
let yaml = try Yams.serialize(node: map)
yaml == """
{array: [1, 2, 3]}

"""
let node = try Yams.compose(yaml: yaml)
map == node

Integrating with Combine

When Apple's Combine framework is available, YAMLDecoder conforms to the TopLevelDecoder protocol, which allows it to be used with the decode(type:decoder:) operator:

import Combine
import Foundation
import Yams

func fetchBook(from url: URL) -> AnyPublisher<Book, Error> {
    URLSession.shared.dataTaskPublisher(for: url)
        .map(\.data)
        .decode(type: Book.self, decoder: YAMLDecoder())
        .eraseToAnyPublisher()
}

Download Details:

Author: jpsim
Source code: https://github.com/jpsim/Yams

License: MIT license
#swift #yaml

Vincent Lab

1605178175

The Basics of YAML in Under 5 Minutes

In this video, I’ll be showing you the very basics of YAML in under 5-minutes so you can get started.

#yaml #under 5 minutes #the basics of yaml #learn yaml in five minutes #everything you need to get started #yaml tutorial

Vincent Lab

1621373427

Getting Started with YAML in Node

In this video, I’ll be showing you how to get started with YAML in Node.js

#yaml #web development #js-yaml #tutorial #yaml tutorial #javascript

Oral Brekke

1646022300

js-yaml: Very fast YAML parser

JS-YAML - YAML 1.2 parser / writer for JavaScript

Online Demo

This is an implementation of YAML, a human-friendly data serialization language. Started as PyYAML port, it was completely rewritten from scratch. Now it's very fast, and supports 1.2 spec.

Installation

YAML module for node.js

npm install js-yaml

CLI executable

If you want to inspect your YAML files from CLI, install js-yaml globally:

npm install -g js-yaml

Usage

usage: js-yaml [-h] [-v] [-c] [-t] file

Positional arguments:
  file           File with YAML document(s)

Optional arguments:
  -h, --help     Show this help message and exit.
  -v, --version  Show program's version number and exit.
  -c, --compact  Display errors in compact mode
  -t, --trace    Show stack trace on error

API

Here we cover the most 'useful' methods. If you need advanced details (creating your own tags), see examples for more info.

const yaml = require('js-yaml');
const fs   = require('fs');

// Get document, or throw exception on error
try {
  const doc = yaml.load(fs.readFileSync('/home/ixti/example.yml', 'utf8'));
  console.log(doc);
} catch (e) {
  console.log(e);
}

load (string [ , options ])

Parses string as single YAML document. Returns either a plain object, a string, a number, null or undefined, or throws YAMLException on error. By default, does not support regexps, functions and undefined.

options:

filename (default: null) - string to be used as a file path in error/warning messages.
onWarning (default: null) - function to call on warning messages. Loader will call this function with an instance of YAMLException for each warning.
schema (default: DEFAULT_SCHEMA) - specifies a schema to use.
- FAILSAFE_SCHEMA - only strings, arrays and plain objects: http://www.yaml.org/spec/1.2/spec.html#id2802346
- JSON_SCHEMA - all JSON-supported types: http://www.yaml.org/spec/1.2/spec.html#id2803231
- CORE_SCHEMA - same as JSON_SCHEMA: http://www.yaml.org/spec/1.2/spec.html#id2804923
- DEFAULT_SCHEMA - all supported YAML types.
json (default: false) - compatibility with JSON.parse behaviour. If true, then duplicate keys in a mapping will override values rather than throwing an error.

NOTE: This function does not understand multi-document sources, it throws exception on those.

NOTE: JS-YAML does not support schema-specific tag resolution restrictions. So, the JSON schema is not as strictly defined in the YAML specification. It allows numbers in any notation, use Null and NULL as null, etc. The core schema also has no such restrictions. It allows binary notation for integers.

loadAll (string [, iterator] [, options ])

Same as load(), but understands multi-document sources. Applies iterator to each document if specified, or returns array of documents.

const yaml = require('js-yaml');

yaml.loadAll(data, function (doc) {
  console.log(doc);
});

dump (object [ , options ])

Serializes object as a YAML document. Uses DEFAULT_SCHEMA, so it will throw an exception if you try to dump regexps or functions. However, you can disable exceptions by setting the skipInvalid option to true.

options:

indent (default: 2) - indentation width to use (in spaces).
noArrayIndent (default: false) - when true, will not add an indentation level to array elements
skipInvalid (default: false) - do not throw on invalid types (like function in the safe schema) and skip pairs and single values with such types.
flowLevel (default: -1) - specifies level of nesting, when to switch from block to flow style for collections. -1 means block style everwhere
styles - "tag" => "style" map. Each tag may have own set of styles.
schema (default: DEFAULT_SCHEMA) specifies a schema to use.
sortKeys (default: false) - if true, sort keys when dumping YAML. If a function, use the function to sort the keys.
lineWidth (default: 80) - set max line width. Set -1 for unlimited width.
noRefs (default: false) - if true, don't convert duplicate objects into references
noCompatMode (default: false) - if true don't try to be compatible with older yaml versions. Currently: don't quote "yes", "no" and so on, as required for YAML 1.1
condenseFlow (default: false) - if true flow sequences will be condensed, omitting the space between a, b. Eg. '[a,b]', and omitting the space between key: value and quoting the key. Eg. '{"a":b}' Can be useful when using yaml for pretty URL query params as spaces are %-encoded.
quotingType (' or ", default: ') - strings will be quoted using this quoting style. If you specify single quotes, double quotes will still be used for non-printable characters.
forceQuotes (default: false) - if true, all non-key strings will be quoted even if they normally don't need to.
replacer - callback function (key, value) called recursively on each key/value in source object (see replacer docs for JSON.stringify).

The following table show availlable styles (e.g. "canonical", "binary"...) available for each tag (.e.g. !!null, !!int ...). Yaml output is shown on the right side after => (default setting) or ->:

!!null
  "canonical"   -> "~"
  "lowercase"   => "null"
  "uppercase"   -> "NULL"
  "camelcase"   -> "Null"
  "empty"       -> ""

!!int
  "binary"      -> "0b1", "0b101010", "0b1110001111010"
  "octal"       -> "0o1", "0o52", "0o16172"
  "decimal"     => "1", "42", "7290"
  "hexadecimal" -> "0x1", "0x2A", "0x1C7A"

!!bool
  "lowercase"   => "true", "false"
  "uppercase"   -> "TRUE", "FALSE"
  "camelcase"   -> "True", "False"

!!float
  "lowercase"   => ".nan", '.inf'
  "uppercase"   -> ".NAN", '.INF'
  "camelcase"   -> ".NaN", '.Inf'

Example:

dump(object, {
  'styles': {
    '!!null': 'canonical' // dump null as ~
  },
  'sortKeys': true        // sort object keys
});

Supported YAML types

The list of standard YAML tags and corresponding JavaScript types. See also YAML tag discussion and YAML types repository.

!!null ''                   # null
!!bool 'yes'                # bool
!!int '3...'                # number
!!float '3.14...'           # number
!!binary '...base64...'     # buffer
!!timestamp 'YYYY-...'      # date
!!omap [ ... ]              # array of key-value pairs
!!pairs [ ... ]             # array or array pairs
!!set { ... }               # array of objects with given keys and null values
!!str '...'                 # string
!!seq [ ... ]               # array
!!map { ... }               # object

JavaScript-specific tags

See js-yaml-js-types for extra types.

Caveats

Note, that you use arrays or objects as key in JS-YAML. JS does not allow objects or arrays as keys, and stringifies (by calling toString() method) them at the moment of adding them.

---
? [ foo, bar ]
: - baz
? { foo: bar }
: - baz
  - baz

{ "foo,bar": ["baz"], "[object Object]": ["baz", "baz"] }

Also, reading of properties on implicit block mapping keys is not supported yet. So, the following YAML document cannot be loaded.

&anchor foo:
  foo: bar
  *anchor: duplicate key
  baz: bat
  *anchor: duplicate key

js-yaml for enterprise

Available as part of the Tidelift Subscription

The maintainers of js-yaml and thousands of other packages are working with Tidelift to deliver commercial support and maintenance for the open source dependencies you use to build your applications. Save time, reduce risk, and improve code health, while paying the maintainers of the exact dependencies you use. Learn more.

Author: Nodeca
Source Code: https://github.com/nodeca/js-yaml
License: MIT License

#node #yaml #javascript

Yams: A Sweet and Swifty YAML Parser

Yams

Installation

CMake

Swift Package Manager

CocoaPods

Carthage

Bazel

Usage

Codable types

Swift Standard Library types

Yams.Node

Integrating with Combine

Download Details:

What is GEEK

Buddha Community

Yams: A Sweet and Swifty YAML Parser

Yams

Installation

CMake

Swift Package Manager

CocoaPods

Carthage

Bazel

Usage

Codable types

Swift Standard Library types

Yams.Node

Integrating with Combine

Download Details:

Yams: A Sweet and Swifty YAML Parser

Yams

Installation

CMake

Swift Package Manager

CocoaPods

Carthage

Bazel

Usage

Codable types

Swift Standard Library types

Yams.Node

Integrating with Combine

Download Details:

The Basics of YAML in Under 5 Minutes

Getting Started with YAML in Node

js-yaml: Very fast YAML parser

Installation

YAML module for node.js

CLI executable

Usage

API

load (string [ , options ])

loadAll (string [, iterator] [, options ])

dump (object [ , options ])

Supported YAML types

Caveats

js-yaml for enterprise

`Codable` types

`Yams.Node`

`Codable` types

`Yams.Node`

`Codable` types

`Yams.Node`