Model and manipulate data with ES6 classes, JSON Schema initialization and validation, JSON Patch, JSON Pointer, and JSON Mappings.
Alpha code undergoing rigorous testing and refactoring prior to first production release.
From npm registry:
$ npm install json-document@beta
From GitHub repository:
$ npm install https://github.com/anvilresearch/json-document.git
const {
,
JSONSchema,
JSONMapping,
JSONPatch,
JSONPointer,
JSONDocument
Formats= require('json-document') }
JSONSchema
is a class that implements initialization and
validation of JSON/JavaScript values based on the JSON Schema standard.
The initialize
and validate
methods of this
class are compiled into simple "flat" code without iteration for
performance.
let schema = new JSONSchema({
type: 'object',
properties: {
foo: { maxLength: 5 }
}
})
.validate({ foo: 'too long' })
schema// => { valid: false, errors: [{...}] }
Schemas can be extended. This is useful for class inheritance, as we'll see with JSONDocument.
let extended = schema.extend({
type: ['object', 'array'],
items: { type: 'integer' }
})
// => JSONSchema {
// type: ['object', 'array'],
// properties: { foo: { maxLength: 5 } }
// items: { type: 'integer' } }
All JSON Schema validation keywords are currently supported except
for ref
, remoteRef
, and
definitions
.
JSON Mappings can read data from one data structure and write to a different one. This is useful for translating data received in one format into another format, for example getting user info from Facebook and storing it in our user records, which have a different schema.
Mappings must be declared before use. They're expressed as an object with JSON Pointer strings for keys and values.
let mapping = new JSONMapping({
'/foobar': '/foo/bar/0'
})
Now, give a source object to read from and a target object to write to, we can map and project over a map.
let target = {}
let source = { foo: { bar: ['baz'] } }
.map(target, source)
mapping// target => { foobar: 'baz' }
JSON Mappings also have a method for the reverse operation called
project
.
JSON Patch describes modifications to an object that are impossible to achieve by simple property assignment approaches. For example, if the value of a key in an update object is undefined, does that mean the new value is undefined, that the key should be deleted, or that no change should be made. JSON Patch eliminates that kind of ambiguity.
Given a target object { "foo": ["bar", "qux", "baz"] }
,
we could remove the second element of the foo
array like
so:
let patch = new JSONPatch([
op: 'remove', path: '/foo/1' }
{
])
let target = { foo: ['bar', 'qux', 'baz'] }
.apply(target)
patch// target is mutated to
// =>
// { foo: [ 'bar', 'baz' ] }
JSONPointer
can parse JSON Pointer strings and use them
to get
, add
, replace
, and
remove
values from an object.
let pointer = new JSONPointer('/foo/1')
let object = { foo: ['bar', 'baz'] }
.get(object) // => 'baz'
pointer.add(object, 'qux') // => { foo: ['bar', 'qux', 'baz'] }
pointer.replace(object, 'quux') // => { foo: ['bar', 'quux', 'baz'] }
pointer.remove(object) // => { foo: ['bar', 'baz'] } pointer
class Foo extends JSONDocument {
static get schema () {
return schema // JSONSchema instance
}
}
let foo = new Foo({ a: 1, b: 2 })
.validate()
foo// if valid => { valid: true, errors: [] }
// if invalid => { valid: false, errors: [{...}, {...}, ...] }
.patch([{ op: 'add', path: '/c', value: 3 }])
foo.project(mapping) foo
JSONSchema can be extended with additional named formats.
pattern
can be a RegExp instance or a string representation
of a regular expression.
.register('new-format', pattern)
Formats
let schema = new JSONSchema({
type: 'string',
format: 'new-format'
})
$ npm test
$ npm run karma
Copyright (c) 2016 Anvil Research, Inc.