Gotu Kola helps define your business entities (*)
(*) Entities: they are the first natural place we should aim to place business logic in domain-driven applications.
$ npm install @herbsjs/gotu
const { entity, field } = require('@herbsjs/gotu')
const Feature =
entity('Feature', {
name: field(String),
hasAccess: field(Boolean)
})
const Plan =
entity('Plan', {
name: field(String),
monthlyCost: field(Number)
})
const User =
entity('User', {
name: field(String),
lastAccess: field(Date),
accessCount: field(Number),
features: field([Feature]),
plan: field(Plan),
})
const user = new User()
user.name = "Beth"
user.plan.monthlyCost = 10
user.features = [
new Feature(),
new Feature(),
new Feature()
]
user.validate()To clone the entity, we can use entity.fromJSON(), like the example below:
const Customer =
entity('Customer', {
name: field(String),
age: field(Number),
gender: field(String)
})
const customer1 = new Customer()
customer1.name = 'John Doe'
customer1.age = 20
customer1.gender = 'Male'
const customer2 = Customer.fromJSON(customer1)
//customer1.name = 'John Doe'
//customer1.age = 20
//customer1.gender = 'Male'To do a clone changing original entity, you can use desestructuring method, like this:
const Customer =
entity('Customer', {
name: field(String),
age: field(Number),
gender: field(String)
})
const customer1 = new Customer()
customer1.name = 'John Doe'
customer1.age = 20
customer1.gender = 'Male'
const customer2 = Customer.fromJSON({ ...customer1, name: 'Billy Jean' })
//customer1.name = 'Billy Jean'
//customer1.age = 20
//customer1.gender = 'Male'A value of an field can be validated against the field type or its custom validation.
const Plan =
entity('Plan', {
...
monthlyCost: field(Number),
})
const User =
entity('User', {
name: field(String),
plan: field(Plan)
})
const user = new User()
user.name = 42
user.plan.monthlyCost = true
user.validate()
user.errors // { name: [ wrongType: 'String' ], plan: { monthlyCost: [ wrongType: 'Number' ] } }
user.isValid() // falseYou can also simplify you validation method using isValid() method that execute validate implicit for you entity and return true/false in a single execution and also you can check the errors.
const Plan =
entity('Plan', {
...
monthlyCost: field(Number),
})
const plan = new Plan()
plan.plan.monthlyCost = true
plan.isValid() // false
plan.errors // { monthlyCost: [ wrongType: 'Number' ] }You can ignore id field validation using isValid({exceptIDs: true}). Example: Imagine that your id should not be null, but sometimes, in an insertion case, the ID only exists after an insertion in the database, so you can validate the hole entity, except the id field.
const Plan =
entity('Plan', {
...
myId: id(Number),
monthlyCost: field(Number),
})
const plan = new Plan()
plan.plan.myId = '123'
plan.plan.monthlyCost = 500
plan.isValid({exceptIDs: true}) // true
plan.isValid() // false
plan.errors // { }You can validate only id field validation using isValid({onlyIDs: true}). Example: Imagine that your entity you want to validate only the id because you should insert first the id.
const Plan =
entity('Plan', {
...
myId: id(Number),
monthlyCost: field(Number),
})
const plan = new Plan()
plan.plan.myId = 123
plan.plan.monthlyCost = '500'
plan.isValid({onlyIDs: true}) // true
plan.isValid() // false
plan.errors // { myId: [ wrongType: 'Number' ] }You can validate references too. Gotu will automatically validate subentities, however with the reference key, you can select whether you want to validate only the Ids or except the Ids
const AnEntity1 = entity('A entity', {
id1: id(Number, { validation: { presence: true } }),
field1: field(String, { validation: { presence: true } })
})
const AnEntity2 = entity('A entity', {
id21: id(Number, { validation: { presence: true } }),
id22: id(String, { validation: { presence: true } }),
field2: field(String, { validation: { presence: true } }),
fieldEntity2: field(AnEntity1, { validation: { presence: true } }),
fieldEntities2: field([AnEntity1], { validation: { presence: true } })
})
const AnEntity3 = entity('A entity', {
id3: id(Number, { validation: { presence: true } }),
field3: field(String, { validation: { presence: true } }),
fieldEntity3: field(AnEntity2, { validation: { presence: true } })
})
const instance = AnEntity3.fromJSON({
id3: '3',
field3: undefined,
fieldEntity3: {
id21: '2',
id22: 2,
field2: 'value2',
fieldEntity2: { id1: undefined, field1: 'value1' },
fieldEntities2: [
{ id1: '1', field1: undefined },
{ id1: undefined, field1: 'value1' }]
}
})
instance.validate({ references: { onlyIDs: true } })
instance.errors /*
{ id3: [{ wrongType: 'Number' }],
field3: [{ cantBeEmpty: true }],
fieldEntity3: {
id21: [{ wrongType: 'Number' }],
id22: [{ wrongType: 'String' }],
}})}*/For custom validation Gotu uses Herbs JS Suma library under the hood. It has no message defined, only error codes.
Use { validation: ... } to specify a valid Suma validation (sorry) on the field definition.
const User =
entity('User', {
...
password: field(String, { validation: {
presence: true,
length: { minimum: 6 } }
}),
cardNumber: field(String, { validation: {
custom: { invalidCardNumber: (value) => value.length === 16 } }
})
})
const user = new User()
user.password = '1234'
user.cardNumber = '1234456'
user.validate()
user.errors // [{ password: [ { isTooShort: 6 } ] , { "invalidCardNumber": true }]
user.isValid // falseReturns a new instance of a entity
const User =
entity('User', {
name: field(String)
})
// from object
const user = User.fromJSON({ name: 'Beth'})
// or string
const user = User.fromJSON(`{ "name": "Beth"}`)By default fromJSON serializes only keys that have been defined in the entity. If you want to add other keys during serialization, use .fromJSON(data, { allowExtraKeys: true }).
By default, fromJSON default field values will be applied for keys not present in value.
To serialize an entity to JSON string use JSON.stringify or entity.toJSON function.
const json = JSON.stringify(user) // { "name": "Beth" }By default toJSON serializes only keys that have been defined in the entity. If you want to add other keys during serialization, use entity.toJSON({ allowExtraKeys: true }).
A entity field type has a name, type, default value, validation and more.
A field in an entity can be of basic types, the same as those used by JavaScript:
Number: double-precision 64-bit binary format IEEE 754 value
String: a UTF‐16 character sequence
Boolean: true or false
Date: represents a single moment in time in a platform-independent format.
const User =
entity('User', {
name: field(String),
lastAccess: field(Date),
accessCount: field(Number),
hasAccess: field(Boolean)
})For complex types, with deep relationship between entities, a field can be of entity type:
const Plan =
entity('Plan', {
...
monthlyCost: field(Number),
})
const User =
entity('User', {
...
plan: field(Plan)
})For complex types, with deep relationship between entities, a field can contain a list of entity type:
const Plan =
entity('Plan', {
...
monthlyCost: field(Number),
})
const User =
entity('User', {
...
plan: field([Plan])
})It is possible to declare a field as an ID. This metadata will be used by glues to enrich the infrastructure interfaces (Database, REST, GraphQL, etc).
We can do it in two ways:
// The explicit way
const User =
entity('User', {
id: field(Number, { isId: true }),
...
})
// The short way
const User =
entity('User', {
id: id(Number),
...
})It is possible to define a default value when an entity instance is initiate.
const User =
entity('User', {
...
hasAccess: field(Boolean, { default: false })
})
const user = new User()
user.hasAccess // falseIf the default value is a function it will call the function and return the value as default value:
const User =
entity('User', {
...
hasAccess: field(Boolean, { default: () => false })
})
const user = new User()
user.hasAccess // falseFor scalar types a default value is assumed if a default value is not given:
| Type | Default Value |
|---|---|
Number |
0 |
String |
"" |
Boolean |
false |
Date |
null |
For entity types the default value is a new instance of that type. It is possible to use null as default:
const User =
entity('User', {
...
plan: field(Plan, { default: null })
})
const user = new User()
user.plan // nullA method can be defined to create custom behaviour in an entity:
const User =
entity('User', {
...
role: field(String),
hasAccess() { return this.role === "admin" },
})
const user = new User()
const access = user.hasAccess()Check if a instance is the same type from its parent entity class (similar to instanceOf)
const AnEntity = entity('A entity', {})
const AnSecondEntity = entity('A second entity', {})
const instance1 = new AnEntity()
const instance2 = new AnSecondEntity()
AnEntity.parentOf(instance1) // true
AnEntity.parentOf(instance2) // falseCheck if an object is a Gotu Entity class
const AnEntity = entity('A entity', {})
const instance1 = new AnEntity()
entity.isEntity(AnEntity) // true
entity.isEntity(Object) // falseIt is possible to access the schema information of your entity. There are two special properties:
Returns an list with all the fields of the entity:
const User = entity('User', {
id: id(Number),
name: field(String, { validation: { presence: true }})
})
const fields = User.schema.fields
// results in
// [
// Field {
// name: 'id',
// type: [Function: Number],
// options: { isId: true },
// _validations: null
// },
// Field {
// name: 'name',
// type: [Function: String],
// options: { validation: [Object] },
// _validations: null
// }
// ]If the entity has no field, so it returns an emtpy array ([])
Returns an list with all the ids of the entity:
const User = entity('User', {
id: id(Number),
anotherId: field(String, { isId: true }),
name: field(String)
})
const ids = User.schema.ids
// results in
// [
// Field {
// name: 'id',
// type: [Function: Number],
// options: { isId: true },
// _validations: null
// },
// Field {
// name: 'anotherId',
// type: [Function: String],
// options: { isId: true },
// _validations: null
// }
// ]If the entity has no id, so it returns an emtpy array ([])
Another way to verify if a specific property is an id, is accessing the isId property in the field's options, like this:
const user = new User()
//should be equals ```true```
user.__proto__.meta.schema.id.options.isId- Field basic JS type definition and validation (ex: "name": String)
- Field entity type definition and validation (ex: "user": User)
- Field enum type definition and validation (ex: "paymentType": ['CC', 'Check'])
- Field list type definition and validation (ex: "users": [User])
- Entity custom methods (ex: payment.calculate())
- Default values
- Entity (complex) validation (ex: payment.validate() )
- Field validation error message (ex: payment.errors )
- Field validation error code (ex: payment.errors )
- Entity hidrate (ex: fromJson)
- Entity serialize (ex: toJson)
- Extend / Custom field validation (ex: email, greater than, etc)
- Valitation contexts (ex: Payment validation for [1] credit card or [2] check)
- Conditional Validation (ex: if email is present, emailConfirmation must be present)
- Entities Inheritance (schema and validations inheritance)
Come with us to make an awesome Gotu.
Now, if you do not have technical knowledge and also have intend to help us, do not feel shy, click here to open an issue and collaborate their ideas, the contribution may be a criticism or a compliment (why not?)
If you would like to help contribute to this repository, please see CONTRIBUTING
Gotu Kola has been used historically to relieve congestion from upper respiratory infections and colds and for wound healing. It is very popular for treating varicose veins and memory loss.
https://en.wikipedia.org/wiki/Centella_asiatica
Gotu is released under the MIT license.