immutable-json-pointer

JSON Pointer (RFC6901) implementation for Node.js

Mutate a copy of data without changing the original source.

Install

``bash
// NPM
$ npm install immutable-json-pointer

// yarn v2
$ yarn add immutable-json-pointer
`

Usage

$3

`typescript
import { get } from "immutable-json-pointer";
// For example, given the JSON document
const json = {
foo: ["bar", "baz"],
"": 0,
"a/b": 1,
"c%d": 2,
"e^f": 3,
"g|h": 4,
"i\\j": 5,
'k"l': 6,
" ": 7,
"m~n": 8,
};
// The following JSON strings evaluate to the accompanying values:
expect(get(json, "")).toBe(json); // the whole document
expect(get(json, "/foo")).toStrictEqual(["bar", "baz"]);
expect(get(json, "/foo/0")).toBe("bar");
expect(get(json, "/")).toBe(0);
expect(get(json, "/a~1b")).toBe(1);
expect(get(json, "/c%d")).toBe(2);
expect(get(json, "/e^f")).toBe(3);
expect(get(json, "/g|h")).toBe(4);
expect(get(json, "/i\\j")).toBe(5);
expect(get(json, '/k"l')).toBe(6);
expect(get(json, "/ ")).toBe(7);
expect(get(json, "/m~0n")).toBe(8);
`

$3

`typescript
import { set } from "immutable-json-pointer";
// For example, given the JSON document
const json = {
foo: ["bar", "baz"],
hoge: {
fuga: "piyo",
},
};
const newJson = set(json, "/foo/-", "boss");

expect(newJson === json).toBeFalsy();
expect(newJson.hoge === json.hoge).toBeTruthy();
expect(newJson.foo === json.foo).toBeFalsy();
expect(newJson.foo[2]).toBe("boss");

const json2 = {};

const newJson2 = set(json2, "/quuux/0", "ax"); // { "quuux" : ["ax"] }
exepct(Array.isArray(newJson2.quuux)).toBe(true);
`

$3

`typescript
import { has } from "immutable-json-pointer";
const json = {
value: 1,
};
has(json, "/value"); // true
has(json, "/item"); // false
`

$3

`typescript
import { read } from "immutable-json-pointer";
const json = {
value: 1,
};
read(json, "/value"); // 1
read(json, "/item"); // undefined
`

$3

`typescript
import { remove } from "immutable-json-pointer";
const json = {
unused: 0,
value: 1,
};
const newJson = remove(json, "/unused");
console.log(newJSON); // { value: 1 }
console.log(json); // { unused: 0, value: 1 }
`

$3

`typescript
import { dict } from "immutable-json-pointer";
const json = {
item: 0,
value: 1,
};
const dic = dict(json);
console.log(dic); // { '/item': 0, '/value': 1 }
`

$3

`typescript
import { compile } from "immutable-json-pointer";
console.log(compile(["a", "b", "c"])); // "/a/b/c"
`

$3

`typescript
import { transform } from "immutable-json-pointer";
const json = {
value: 0,
};
const nextValue = 1;
const json2 = transform(json, "/value", (prev, path) => {
if (prev != nextValue) {
return nextValue;
}
return prev;
});
console.log(json); // { "value": 0 }
console.log(json2); // { "value": 1 }
`

$3

`typescript
import { chain } from "immutable-json-pointer";
const doc = {
foo: {
bar: {
baz: 1,
},
},
};
const operation = chain(
(doc) => set(doc, "/foo/bar/baz", 2),
(doc) => set(doc, "/foo/bar/baz", 3),
(doc) => set(doc, "/foo/bar/baz", 4)
);
const result = operation(doc);
console.log(result); // { foo:{ bar: { baz: 4 } } }
``