J'ai écrit ma propre petite bibliothèque autour de cela, récemment, qui essaie de rester aussi proche de
5.1 Modèle de traitement (XSLT REC)
https://www.w3.org/TR/xslt#section-Processing-Model
comme c'est possible (comme je pourrais de toute façon), en quelques lignes de code JavaScript.
Voici quelques exemples d'utilisation pas tout à fait triviaux ...
1. JSON-to-some-markup:
Violon: https://jsfiddle.net/YSharpLanguage/kj9pk8oz/10
(inspiré par l' exemple de document D.1 (XSLT REC) https://www.w3.org/TR/xslt#section-Document-Example )
où ce:
var D1document = {
type: "document", title: [ "Document Title" ],
"": [
{ type: "chapter", title: [ "Chapter Title" ],
"": [
{ type: "section", title: [ "Section Title" ],
"": [
{ type: "para", "": [ "This is a test." ] },
{ type: "note", "": [ "This is a note." ] }
] },
{ type: "section", title: [ "Another Section Title" ],
"": [
{ type: "para", "": [ "This is ", { emph: "another" }, " test." ] },
{ type: "note", "": [ "This is another note." ] }
] }
] }
] };
var D1toHTML = { $: [
[ [ function(node) { return node.type === "document"; } ],
function(root) {
return "<html>\r\n\
<head>\r\n\
<title>\r\n\
{title}\r\n".of(root) + "\
</title>\r\n\
</head>\r\n\
<body>\r\n\
{*}".of(root[""].through(this)) + "\
</body>\r\n\
</html>";
}
],
[ [ function(node) { return node.type === "chapter"; } ],
function(chapter) {
return " <h2>{title}</h2>\r\n".of(chapter) + "{*}".of(chapter[""].through(this));
}
],
[ [ function(node) { return node.type === "section"; } ],
function(section) {
return " <h3>{title}</h3>\r\n".of(section) + "{*}".of(section[""].through(this));
}
],
[ [ function(node) { return node.type === "para"; } ],
function(para) {
return " <p>{*}</p>\r\n".of(para[""].through(this));
}
],
[ [ function(node) { return node.type === "note"; } ],
function(note) {
return ' <p class="note"><b>NOTE: </b>{*}</p>\r\n'.of(note[""].through(this));
}
],
[ [ function(node) { return node.emph; } ],
function(emph) {
return "<em>{emph}</em>".of(emph);
}
]
] };
console.log(D1document.through(D1toHTML));
... donne:
<html>
<head>
<title>
Document Title
</title>
</head>
<body>
<h2>Chapter Title</h2>
<h3>Section Title</h3>
<p>This is a test.</p>
<p class="note"><b>NOTE: </b>This is a note.</p>
<h3>Another Section Title</h3>
<p>This is <em>another</em> test.</p>
<p class="note"><b>NOTE: </b>This is another note.</p>
</body>
</html>
et
2. JSON à JSON:
Violon: https://jsfiddle.net/YSharpLanguage/ppfmmu15/10
où ce:
// (A "Company" is just an object with a "Team")
function Company(obj) {
return obj.team && Team(obj.team);
}
// (A "Team" is just a non-empty array that contains at least one "Member")
function Team(obj) {
return ({ }.toString.call(obj) === "[object Array]") &&
obj.length &&
obj.find(function(item) { return Member(item); });
}
// (A "Member" must have first and last names, and a gender)
function Member(obj) {
return obj.first && obj.last && obj.sex;
}
function Dude(obj) {
return Member(obj) && (obj.sex === "Male");
}
function Girl(obj) {
return Member(obj) && (obj.sex === "Female");
}
var data = { team: [
{ first: "John", last: "Smith", sex: "Male" },
{ first: "Vaio", last: "Sony" },
{ first: "Anna", last: "Smith", sex: "Female" },
{ first: "Peter", last: "Olsen", sex: "Male" }
] };
var TO_SOMETHING_ELSE = { $: [
[ [ Company ],
function(company) {
return { some_virtual_dom: {
the_dudes: { ul: company.team.select(Dude).through(this) },
the_grrls: { ul: company.team.select(Girl).through(this) }
} }
} ],
[ [ Member ],
function(member) {
return { li: "{first} {last} ({sex})".of(member) };
} ]
] };
console.log(JSON.stringify(data.through(TO_SOMETHING_ELSE), null, 4));
... donne:
{
"some_virtual_dom": {
"the_dudes": {
"ul": [
{
"li": "John Smith (Male)"
},
{
"li": "Peter Olsen (Male)"
}
]
},
"the_grrls": {
"ul": [
{
"li": "Anna Smith (Female)"
}
]
}
}
}
3. XSLT contre JavaScript:
Un équivalent JavaScript de ...
XSLT 3.0 REC Section 14.4 Exemple: regroupement de nœuds en fonction de valeurs communes
(à: http://jsfiddle.net/YSharpLanguage/8bqcd0ey/1 )
Cf. https://www.w3.org/TR/xslt-30/#grouping-examples
où...
var cities = [
{ name: "Milano", country: "Italia", pop: 5 },
{ name: "Paris", country: "France", pop: 7 },
{ name: "München", country: "Deutschland", pop: 4 },
{ name: "Lyon", country: "France", pop: 2 },
{ name: "Venezia", country: "Italia", pop: 1 }
];
/*
Cf.
XSLT 3.0 REC Section 14.4
Example: Grouping Nodes based on Common Values
https://www.w3.org/TR/xslt-30/#grouping-examples
*/
var output = "<table>\r\n\
<tr>\r\n\
<th>Position</th>\r\n\
<th>Country</th>\r\n\
<th>City List</th>\r\n\
<th>Population</th>\r\n\
</tr>{*}\r\n\
</table>".of
(
cities.select().groupBy("country")(function(byCountry, index) {
var country = byCountry[0],
cities = byCountry[1].select().orderBy("name");
return "\r\n\
<tr>\r\n\
<td>{position}</td>\r\n\
<td>{country}</td>\r\n\
<td>{cities}</td>\r\n\
<td>{population}</td>\r\n\
</tr>".
of({ position: index + 1, country: country,
cities: cities.map(function(city) { return city.name; }).join(", "),
population: cities.reduce(function(sum, city) { return sum += city.pop; }, 0)
});
})
);
... donne:
<table>
<tr>
<th>Position</th>
<th>Country</th>
<th>City List</th>
<th>Population</th>
</tr>
<tr>
<td>1</td>
<td>Italia</td>
<td>Milano, Venezia</td>
<td>6</td>
</tr>
<tr>
<td>2</td>
<td>France</td>
<td>Lyon, Paris</td>
<td>9</td>
</tr>
<tr>
<td>3</td>
<td>Deutschland</td>
<td>München</td>
<td>4</td>
</tr>
</table>
4. JSONiq contre JavaScript:
Un équivalent JavaScript de ...
Cas d'utilisation de JSONiq Section 1.1.2. Regroupement des requêtes pour JSON
(à: https://jsfiddle.net/YSharpLanguage/hvo24hmk/3 )
Cf. http://jsoniq.org/docs/JSONiq-usecases/html-single/index.html#jsongrouping
où...
/*
1.1.2. Grouping Queries for JSON
http://jsoniq.org/docs/JSONiq-usecases/html-single/index.html#jsongrouping
*/
var sales = [
{ "product" : "broiler", "store number" : 1, "quantity" : 20 },
{ "product" : "toaster", "store number" : 2, "quantity" : 100 },
{ "product" : "toaster", "store number" : 2, "quantity" : 50 },
{ "product" : "toaster", "store number" : 3, "quantity" : 50 },
{ "product" : "blender", "store number" : 3, "quantity" : 100 },
{ "product" : "blender", "store number" : 3, "quantity" : 150 },
{ "product" : "socks", "store number" : 1, "quantity" : 500 },
{ "product" : "socks", "store number" : 2, "quantity" : 10 },
{ "product" : "shirt", "store number" : 3, "quantity" : 10 }
];
var products = [
{ "name" : "broiler", "category" : "kitchen", "price" : 100, "cost" : 70 },
{ "name" : "toaster", "category" : "kitchen", "price" : 30, "cost" : 10 },
{ "name" : "blender", "category" : "kitchen", "price" : 50, "cost" : 25 },
{ "name" : "socks", "category" : "clothes", "price" : 5, "cost" : 2 },
{ "name" : "shirt", "category" : "clothes", "price" : 10, "cost" : 3 }
];
var stores = [
{ "store number" : 1, "state" : "CA" },
{ "store number" : 2, "state" : "CA" },
{ "store number" : 3, "state" : "MA" },
{ "store number" : 4, "state" : "MA" }
];
var nestedGroupingAndAggregate = stores.select().orderBy("state").groupBy("state")
( function(byState) {
var state = byState[0],
stateStores = byState[1];
byState = { };
return (
(
byState[state] =
products.select().orderBy("category").groupBy("category")
( function(byCategory) {
var category = byCategory[0],
categoryProducts = byCategory[1],
categorySales = sales.filter(function(sale) {
return stateStores.find(function(store) { return sale["store number"] === store["store number"]; }) &&
categoryProducts.find(function(product) { return sale.product === product.name; });
});
byCategory = { };
return (
(
byCategory[category] =
categorySales.select().orderBy("product").groupBy("product")
( function(byProduct) {
var soldProduct = byProduct[0],
soldQuantities = byProduct[1];
byProduct = { };
return (
(
byProduct[soldProduct] =
soldQuantities.reduce(function(sum, sale) { return sum += sale.quantity; }, 0)
),
byProduct
);
} ) // byProduct()
),
byCategory
);
} ) // byCategory()
),
byState
);
} ); // byState()
... donne:
[
{
"CA": [
{
"clothes": [
{
"socks": 510
}
]
},
{
"kitchen": [
{
"broiler": 20
},
{
"toaster": 150
}
]
}
]
},
{
"MA": [
{
"clothes": [
{
"shirt": 10
}
]
},
{
"kitchen": [
{
"blender": 250
},
{
"toaster": 50
}
]
}
]
}
]
Il est également utile de surmonter les limitations de JSONPath wrt. interroger contre l'axe des ancêtres, comme soulevé par cette question SO (et certainement d'autres).
Par exemple, comment obtenir la remise d'un article d'épicerie en connaissant son identifiant de marque, en
{
"prods": [
{
"info": {
"rate": 85
},
"grocery": [
{
"brand": "C",
"brand_id": "984"
},
{
"brand": "D",
"brand_id": "254"
}
],
"discount": "15"
},
{
"info": {
"rate": 100
},
"grocery": [
{
"brand": "A",
"brand_id": "983"
},
{
"brand": "B",
"brand_id": "253"
}
],
"discount": "20"
}
]
}
?
Une solution possible est:
var products = {
"prods": [
{
"info": {
"rate": 85
},
"grocery": [
{
"brand": "C",
"brand_id": "984"
},
{
"brand": "D",
"brand_id": "254"
}
],
"discount": "15"
},
{
"info": {
"rate": 100
},
"grocery": [
{
"brand": "A",
"brand_id": "983"
},
{
"brand": "B",
"brand_id": "253"
}
],
"discount": "20"
}
]
};
function GroceryItem(obj) {
return (typeof obj.brand === "string") && (typeof obj.brand_id === "string");
}
// last parameter set to "true", to grab all the "GroceryItem" instances
// at any depth:
var itemsAndDiscounts = [ products ].nodeset(GroceryItem, true).
map(
function(node) {
var item = node.value, // node.value: the current "GroceryItem" (aka "$.prods[*].grocery[*]")
discount = node.parent. // node.parent: the array of "GroceryItem" (aka "$.prods[*].grocery")
parent. // node.parent.parent: the product (aka "$.prods[*]")
discount; // node.parent.parent.discount: the product discount
// finally, project into an easy-to-filter form:
return { id: item.brand_id, discount: discount };
}
),
discountOfItem983;
discountOfItem983 = itemsAndDiscounts.
filter
(
function(mapped) {
return mapped.id === "983";
}
)
[0].discount;
console.log("Discount of #983: " + discountOfItem983);
... qui donne:
Discount of #983: 20
«HTH,