readme.md

Jst

The package includes:

1. JSON data structure
2. JSON parser
3. JSON to string
4. Macros to writing JSON same as a Javascript object

Convertors and Macros

Macros

The package support obj!, val!, and arr! macros to write any json object in much more convinces way ( Write like JavaScript Object syntax and getting completion error).

Json macro

    // basic usage

    let dog = obj! {
      color: "brown",
      type: "Akbash",
      eating : [
        "WholeHearted",
        "Royal Canin"
      ]
    };

    // advance usage

    let key = "var_key";
    let age = 45;
    let like_banana = true;

    let person = obj! {
        name: "jhon",
        // use value name as a key
        age,
        like_banana,
        like_rust: true,
        like_go: null,
        emails : [
            "[email protected]",
            "[email protected]"
        ],
        // you can flat obj into - the dog is copy not moved
        ...dog
        address: {
            city: "somewhere",
            zip: 5612
        },
        "literal": true,
        [key]: "var_key",
        age: 56
    };

value macro

Create json::Val enum from any valid json format

let str = val!("some string");
let num = val!(45);
let bool = val!(true);
let null = val!(null);
let array = val!(["string", 45]);

let json = val!({
  key:"string",
  num:45
});

array macro

Create a Vec<json::Val> vector.

// the type is Vec<Val>
let arr = arr![
  "string",
  45,
  true,
  [],
  {key: "value"}
];


// Extend the arr2 by ...arr
let arr2 = arr![
  ...arr,
  "val"
];

Convertors

Form any numerical number, String, &str, boolean and HashMap<String, json::Val> you can call 'into()' method to convert the value to Obj::Val enum

let str:Val = "some string".into();
let num:Val = 78.into();
let bool:Val = true.into();
let array:Val = vec!["string".into(), 45.into()];

// the short way is to use macros (obj!, val! and arr!)

let str = val!("some string");
let num = val!(54);
let bool = val!(true);
let null = val!(null);
let array_val = val!(["string", 45]);
// the type is Vec<Val>
let array = arr!["string", 45];

let obj_val = val!({
  key:"string",
  num:45
});
// the type is Object
let obj = obj!{
  key:"string",
  num:45
};

Parser

Parse a json from a string

use json::{Val, Json};

fn main() {

  let mut j = Obj::new();

  let from_string = Obj::from(
    r#"{
      "number": 56,
      "string": "some string\" string",
      "boolean_true": true,
      "boolean_false": false,
      "null": null,
      "obj": {
        "key1": 456
      },
      "empty_obj": {},
      "empty_obj_new_line": {

      },
      "nested_obj" : {
        "nested1": {
          "nested2": {
            "key1": "some value",
            "key2": "anther value"
          }
        }
      },
      "array": [4564, "some string", {"bla":90, "blo": "sfsf"}, null, true, false, [], [4,5]],
      "key": 2
    }
  "#,
  );


  // Print either json or err
  if let Ok(Val::Obj(v)) = from_string {
    println!("{:?}", v);
  } else if let Err(e) = from_string {
    println!("{:?}", e)
  }
}

let val = Val::from("[3, 5, null]");

if let Ok(v) = val) {
  assert_eq!(v, Val::Array(vec![Val::Num(3.0), Val::Num(5.0), Val::Null])) // true
}

Contribute

Any donation is welcome, open Issues, PR and request for new features.

Limitation

When using in an obj! macro with a big object you need to config #![recursion_limit = "512"]

Todo

1. Improve parser tests
2. Improve indexer (enable to set a value by index)
3. Adding Error code
4. Serialize and Deserialize
5. macro for destructuring object and array
6. Adding json-schema validator
7. Support yml format
8. Option to use share pointer for object and array
9. Consider using the indexmap crate instead of HeadMap (for keeping insert order)

Licence

MIT