ts-jsonify

A simple typescript/json Serializer and deserializer. It allows to configure the mapping through annotations.

Installation

npm i --save ts-jsonify

Usage

class Address {
    @JsonProperty('first-name')
    firstName: string = ""

    @JsonProperty('last-name')
    lastName: string = "";

    street: string = "";
}

class User {
    id: number = 0;
    email: string = "";

    // Non primitive types (will create instances of Address)
    @JsonProperty({ clazz: Adress });
    mainAddress: Address;

    // Use Converter for maps (Custom converters are possible as well
    @JsonProperty({ clazz: Map, converter: MapConverter })
    options: Map<string, any>() = new Map<string, Address>()

    // Ignore fields for serialization
    @JsonIgnore()
    clientSideOptions: any[] = [];

    // There must be an empty constructor
    constructor() {
        this.mainAddress = new Address();
    }
}

let user = new User();
user.email = '[email protected]';
user.options.set('vip', true);
user.clientSideOptions.push("new-user");

// ...

// this object can be used for example to send within an angular service via http
let userDto = JSON.stringify( TsJsonify.serialize(user) );

this.http.post('/users', userDto).subscribe((response) => {
    // get a typed user object.
    let persistedUser = TsJsonify.deserialize<User>(response.json());
})

Undefined and null handling

When deserializing, json null will be treated as javascript null, whereas properties that are not available in the json will be ignored and default value is kept.

When serializing

Custom Converters

You can create your own converters for any property. It must implement the IConverter interface.

export class Uppcase<string>() implements IConverter<string> {

    fromJson(val: string): string {
        return val;
    }

    toJson(val: string): string {
        return val.uppercase();
    }
}

class User {
    @JsonProperty({ converter: Uppcase })
    name = "hans"
}

let jsonObj = TsJsonify.serialize(new User());
console.log(jsonObj.name);
// "HANS"

Known Issues

Non initialized Properties

Due to the concept how TsJsonify works, it can only assign properties that are initialized after instantiating the object, it can be initialized with undefined though.