Crate native_json_macro
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Native JSON for Rust
This crate provides native JSON syntax for Rust, it brings with a powerful way of parsing JSON syntax into native Rust structs. You can declare the JSON object natively as you do with JavaScript, JSON in Rust was made easy!
Note: This crate is just a crude proc-macro (compiler plugin), for more features, please refer to native-json
Usage
Add dependencies to your Cargo.toml, serde_json
is only needed if you want to stringify the JSON object.
[dependencies]
native-json = "1.2"
serde = {version = "1.0", features = ["derive"] }
serde_json = "1.0"
Example of using native JSON object
use native_json::json;
use std::collections::HashMap;
use serde::{Deserialize, Serialize};
fn main()
{
let mut json = json!{
name: "native json",
style: {
color: "red",
size: 12,
bold: true,
range: null
},
array: [5,4,3,2,1],
vector: vec![1,2,3,4,5],
hashmap: HashMap::from([ ("a", 1), ("b", 2), ("c", 3) ]);,
students: [
{name: "John", age: 18},
{name: "Jack", age: 21},
],
};
// Native access
json.style.size += 1;
json.students[0].age += 2;
// Debug
println!("{:#?}", t);
// Stringify
let text = json.string().unwrap();
println!("{}", text);
}
Declare a named JSON struct
With JSON declare syntax, you can declare nested native JSON object in place.
Note: Identifier with underscore suffix will be renamed when serialize and deserialize, type_
will be renamed to type
.
JSON Declare Syntax
json!{
JSON_OBJECT_NAME {
name : type,
value: type?, // optional field when serialize & deserialize
type_: String, // suffix underscore will be removed when serialize & deserialize
array: [type],
object: {
name: type,
...
},
...
}}
The native-json will generate native Rust structs for you, each object is named by object hierarchy path, concatenated with underscore.
JSON_OBJECT_NAME.object
was converted toJSON_OBJECT_NAME_object
JSON_OBJECT_NAME.array's item
was converted toJSON_OBJECT_NAME_array_item
Example of using named JSON object
use native_json::json;
use serde::{Deserialize, Serialize};
use std::collections::HashMap;
json!{
School {
name: String,
rank: u32?, // optional
students: [
{ name: String, age: u16 },
...
],
map: HashMap<String, String>,
nullable: Option<String>
}}
fn main()
{
let mut school = School::new();
school.name = "MIT".to_string();
school.map.insert("Tom".to_owned(), "Profile".to_owned());
// using initializer
let mut john = School_students_item::new();
john.name = "John".to_owned();
john.age = 18;
school.students.push(john);
// using struct
let jack = School_students_item { name: "Jack".to_string(), age: 21 };
school.students.push(jack);
// show
println!("{:#?}", school);
}
Macros
- Declare or instantiate a native JSON object, please refere to module json