feat: implement decode method

README.md

@@ -1,6 +1,6 @@
 # TypeScript Codable
 
-> A Typescript implementation of [Swift Codable](https://developer.apple.com/documentation/swift/codable)
+another strict json parser inspired by [Swift Codable](https://developer.apple.com/documentation/swift/codable) ❤️
 
 ![Alt text](docs/cover.png 'Title')
 
@@ -15,7 +15,7 @@ Works almost same as [Swift Codable](https://developer.apple.com/documentation/s
 
 ## Supported Types
 
-Types design was inspired by [mobx-state-tree](https://github.com/mobxjs/mobx-state-tree#types-overview)
+Types design was inspired by [MobX State Tree](https://github.com/mobxjs/mobx-state-tree#types-overview) ❤️
 
 - Primitives
   - String
@@ -38,7 +38,7 @@ npm install ts-codable
 ## Usage
 
 ```ts
-class Post extends Codable {
+class Post extends BaseCodable {
   title!: string;
   isActive?: boolean;
 }
@@ -51,7 +51,7 @@ Post.CodingProperties = {
   },
 };
 
-class User extends Codable {
+class User extends BaseCodable {
   id!: number;
   username!: string;
   posts!: Post[];
@@ -63,7 +63,7 @@ User.CodingProperties = {
   posts: types.array(Post),
 };
 
-const user: User = new User({
+const user: User = decode(User, {
   id: 123,
   username: 'Gorhom',
   posts: [

package.json

@@ -24,7 +24,7 @@
     "decodable",
     "encoding"
   ],
-  "author": "Gorhom",
+  "author": "Mo Gorhom",
   "license": "MIT",
   "bugs": {
     "url": "https://github.com/Gorhom/ts-codable/issues"
@@ -48,14 +48,14 @@
     "trailingComma": "es5"
   },
   "devDependencies": {
-    "@types/jest": "^24.0.17",
-    "@types/lodash": "^4.14.136",
-    "husky": "^3.0.2",
-    "prettier": "^1.18.2",
-    "pretty-quick": "^1.11.1",
-    "tsdx": "^0.7.2",
+    "@types/jest": "^24.0.24",
+    "@types/lodash": "^4.14.149",
+    "husky": "^3.1.0",
+    "prettier": "^1.19.1",
+    "pretty-quick": "^2.0.1",
+    "tsdx": "^0.12.0",
     "tslib": "^1.10.0",
-    "typescript": "^3.5.3"
+    "typescript": "^3.7.4"
   },
   "dependencies": {
     "lodash": "^4.17.15",

src/codable.ts

@@ -1,15 +1,7 @@
-import get from 'lodash/get';
-import { ICodingPropertyType, IDictionary, decodePayload } from './internal';
+import { ICodingPropertyType, IDictionary, IBaseCodable } from './internal';
 
-export class Codable {
-  static CodingProperties: IDictionary<ICodingPropertyType>;
-  [key: string]: any;
-
-  constructor(payload: object) {
-    Object.assign(this, decodePayload(payload, this.getCodingProperties()));
-  }
-
-  private getCodingProperties = (): IDictionary<ICodingPropertyType> => {
-    return get(this, '__proto__.constructor.CodingProperties', {});
-  };
+export abstract class BaseCodable implements IBaseCodable {
+  public static CodingProperties: IDictionary<ICodingPropertyType>;
+  constructor(payload: object) {}
+  public toJSON = () => '';
 }

src/index.ts

@@ -1 +1 @@
-export { types, Codable } from './internal';
+export { types, BaseCodable, decode } from './internal';

src/internal.ts

@@ -15,5 +15,5 @@ export { optional as optionalModel } from './models/optional';
 export * from './models';
 
 export * from './utils/types';
-export * from './utils/index';
+export * from './utils/typecheck';
 export * from './utils/decoder';

src/models/array.ts

@@ -42,9 +42,7 @@ export const array = (subType?: ISubType): IModel => {
   const decode = (value: any[]) => {
     if (validate(value)) {
       if (isCodable(subType!)) {
-        return value.map(item =>
-          decodePayload(item, subType!.CodingProperties)
-        );
+        return value.map(item => decodePayload(item, subType.CodingProperties));
       }
       return value;
     } else {

src/utils/decoder.ts

@@ -1,13 +1,39 @@
 import get from 'lodash/get';
+import isEmpty from 'lodash/isEmpty';
 import {
   models,
   IType,
   ICodingPropertyType,
   IDictionary,
-  ICodable,
   isCodable,
+  BaseCodable,
 } from '../internal';
-import { IModel } from './types';
+import { IModel, INewable, IBaseCodable, ICodable } from './types';
+
+export const decode = <T extends BaseCodable>(
+  type: INewable<T>,
+  json: any
+): T & IBaseCodable => decodeCodable(type, json, true);
+
+const decodeCodable = <T extends BaseCodable>(
+  type: INewable<T>,
+  json: any,
+  isRoot: boolean
+): T & IBaseCodable => {
+  if (isRoot === false && isEmpty(json) === true) {
+    throw `Missing value for a non optional property`;
+  }
+
+  let result = new type(json);
+
+  // @ts-ignore
+  if (json !== undefined && type.CodingProperties !== undefined) {
+    // @ts-ignore
+    Object.assign(result, decodePayload(json, type.CodingProperties));
+  }
+
+  return result;
+};
 
 export const decodePayload = (
   payload: object,
@@ -34,9 +60,9 @@ export const decodeProperty = (
 
 export const decodeValue = (type: IType | ICodable, value?: object) => {
   if (isCodable(type)) {
-    const object = Object.create(type.prototype);
-    return object.constructor.call(object, value);
+    return decodeCodable(type, value, false);
   }
+
   const model: IModel = models[type.name](type.subtype);
   return model.validate(value) ? model.decode(value) : undefined;
 };

src/utils/typecheck.ts

@@ -0,0 +1,5 @@
+import get from 'lodash/get';
+import { ISubType, BaseCodable, ICodable } from '../internal';
+
+export const isCodable = (type: ISubType): type is ICodable =>
+  get(type, 'prototype', null) instanceof BaseCodable;

src/utils/types.d.ts

@@ -1,6 +1,6 @@
 import has from 'lodash/has';
 import get from 'lodash/get';
-import { Codable, types } from '../internal';
+import { types, BaseCodable } from '../internal';
 
 export interface ICodingProperty {
   type: IType | ICodable;
@@ -31,6 +31,12 @@ export interface IDictionary<T> {
   [index: string]: T;
 }
 
-export type ICodable = INewable<Codable> & {
+export interface IBaseCodable {
+  toJSON: () => string;
+}
+
+interface IBaseCodableStatic {
   CodingProperties: IDictionary<ICodingPropertyType>;
-};
+}
+
+export type ICodable = INewable<BaseCodable> & IBaseCodableStatic;