Core/README.md

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<h1 align="center">
	Sharkitek
</h1>

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	<a href="https://code.zeptotech.net/Sharkitek/Core">Documentation</a> |
	<a href="https://code.zeptotech.net/Sharkitek/Core">Website</a>
</h4>

<p align="center">
	TypeScript library for well-designed model architectures
</p>

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## Introduction

Sharkitek is a lightweight Javascript / TypeScript library designed to ease development of models.

With Sharkitek, you define the architecture of your models by specifying their properties and their types.
Then, you can use the defined methods like `serialize`, `parse`, `patch` or `serializeDiff`.

```typescript
class Example
{
	static model = defineModel({
		Class: Example,
		properties: {
			id: s.property.numeric(),
			name: s.property.string(),
		},
		identifier: "id",
	});
	
	id: number;
	name: string;
}
```

## Quick start

**Note**: by convention, we define our models in a `model` static variable in the model's class. It is a good way to keep your model declaration near the actual class, and its usage will be more natural.

### Model definition

```typescript
/**
 * A person.
 */
class Person
{
	static model = defineModel({
		Class: Person,
		properties: {
			id: s.property.numeric(),
			name: s.property.string(),
			email: s.property.string(),
			createdAt: s.property.date(),
			active: s.property.boolean(),
		},
		identifier: "id",
	});
	
	id: number;
	name: string;
	email: string;
	createdAt: Date;
	active: boolean = true;
}
```

```typescript
/**
 * An article.
 */
class Article
{
	static model = defineModel({
		Class: Article,
		properties: {
			id: s.property.numeric(),
			title: s.property.string(),
			authors: s.property.array(s.property.model(Person)),
			text: s.property.string(),
			evaluation: s.property.decimal(),
			tags: s.property.array(
				s.property.object({
					name: s.property.string(),
				})
			),
		},
		identifier: "id",
	});
	
	id: number;
	title: string;
	authors: Person[] = [];
	text: string;
	evaluation: number;
	tags: {
		name: string;
	}[];
}
```

```typescript
/**
 * A model with composite keys.
 */
class CompositeKeys
{
	static model = defineModel({
		Class: CompositeKeys,
		properties: {
			id1: s.property.numeric(),
			id2: s.property.string(),
		},
		identifier: ["id1", "id2"],
	});
	
	id1: number;
	id2: string;
}
```

### Model functions

#### Serialization

```typescript
const instance = new Person();
instance.id = 1;
instance.createdAt = new Date();
instance.name = "John Doe";
instance.email = "john@doe.test";
instance.active = true;
const serialized = Person.model.model(instance).serialize();
console.log(serialized); // { id: 1, createdAt: "YYYY-MM-DDTHH:mm:ss.sssZ", name: "John Doe", email: "john@doe.test", active: true }
```

#### Deserialization

```typescript
const instance = Person.model.parse({
	id: 1,
	createdAt: "2011-10-05T14:48:00.000Z",
	name: "John Doe",
	email: "john@doe.test",
	active: true,
});
console.log(instance instanceof Person); // true
console.log(instance.createdAt instanceof Date); // true
```

#### Patch

```typescript
const instance = Person.model.parse({
	id: 1,
	createdAt: "2011-10-05T14:48:00.000Z",
	name: "John Doe",
	email: "john@doe.test",
	active: true,
});

instance.name = "Johnny";

// Patch serialized only changed properties and the identifier.
console.log(Person.model.model(instance).patch()); // { id: 1, name: "Johnny" }
// If you run it one more time, already patched properties will not be included again.
console.log(Person.model.model(instance).patch()); // { id: 1 }
```

#### Identifier

```typescript
const instance = new CompositeKeys();
instance.id1 = 5;
instance.id2 = "foo";
const instanceIdentifier = CompositeKeys.model.model(instance).getIdentifier();
console.log(instanceIdentifier); // [5, "foo"]
```

## API

### Types

Types are defined by a class extending `Type`.

Sharkitek defines some basic types by default, in these classes:

- `BooleanType`: boolean value in the model, boolean value in the serialized object.
- `StringType`: string in the model, string in the serialized object.
- `NumericType`: number in the model, number in the serialized object.
- `DecimalType`: number in the model, formatted string in the serialized object.
- `DateType`: date in the model, ISO formatted date in the serialized object.
- `ArrayType`: array in the model, array in the serialized object.
- `ObjectType`: object in the model, object in the serialized object.
- `ModelType`: instance of a specific class in the model, object in the serialized object.

When you are defining a property of a Sharkitek model, you must provide its type by instantiating one of these classes.

```typescript
class Example
{
	static model = defineModel({
		Class: Example,
		properties: {
			foo: s.property.define(new StringType()),
		},
	});
	
	foo: string;
}
```

To ease the use of these classes and reduce read complexity, properties of each type are easily definable with a function for each type.

- `BooleanType` => `s.property.boolean`
- `StringType` => `s.property.string`
- `NumericType` => `s.property.numeric`
- `DecimalType` => `s.property.decimal`
- `DateType` => `s.property.date`
- `ArrayType` => `s.property.array`
- `ObjectType` => `s.property.object`
- `ModelType` => `s.property.model`

Type implementers should provide a corresponding function for each defined type. They can even provide multiple functions or constants with predefined parameters. For example, we could define `s.property.stringArray()` which would be similar to `s.property.array(s.property.string())`.

```typescript
class Example
{
	static model = defineModel({
		Class: Example,
		properties: {
			foo: s.property.string(),
		},
	});
	
	foo: string;
}
```

### Models

#### `model(instance)`

Get a model class (which has all the sharkitek models' functions) from a model instance.

```typescript
const model = definedModel.model(modelInstance);
```

#### `serialize()`

Serialize the model.

Example:

```typescript
const serializedObject = definedModel.model(modelInstance).serialize();
```

#### `parse(serializedObject)`

Deserialize the model.

Example:

```typescript
const modelInstance = definedModel.parse({
	id: 5,
	title: "Hello World!",
	users: [
		{
			id: 6,
			name: "TEST",
		},
	],
});
```

#### `serializeDiff()`

Serialize the difference between current model state and original one.

Example:

```typescript
const modelInstance = definedModel.parse({
	id: 5,
	title: "Hello World!",
	users: [
		{
			id: 6,
			name: "TEST",
		},
	],
});

modelInstance.title = "A new title for a new world";

const result = definedModel.model(modelInstance).serializeDiff();
// if `id` is defined as the model identifier:
// result = { id: 5, title: "A new title for a new world" }
// if `id` is not defined as the model identifier:
// result = { title: "A new title for a new world" }
```

#### `resetDiff()`

Set current properties values as original values.

Example:

```typescript
const modelInstance = definedModel.parse({
	id: 5,
	title: "Hello World!",
	users: [
		{
			id: 6,
			name: "TEST",
		},
	],
});

modelInstance.title = "A new title for a new world";

definedModel.model(modelInstance).resetDiff();

const result = definedModel.model(modelInstance).serializeDiff();
// if `id` is defined as the model identifier:
// result = { id: 5 }
// if `id` is not defined as the model identifier:
// result = {}
```

#### `patch()`

Get difference between original values and current ones, then reset it.
Similar to call `serializeDiff()` then `resetDiff()`.

```typescript
const modelInstance = definedModel.parse({
	id: 5,
	title: "Hello World!",
	users: [
		{
			id: 6,
			name: "TEST",
		},
	],
});

modelInstance.title = "A new title for a new world";

const result = definedModel.model(modelInstance).patch();
// if `id` is defined as the model identifier:
// result = { id: 5, title: "A new title for a new world" }
// if `id` is not defined as the model identifier:
// result = { title: "A new title for a new world" }
```