🚀 Relation maker for Objection.js


This plugin provide a way to create relationship objects between Objection.js models.

Doc

For more documentation, you can view the Github page of this repository.

Installation

$3

``sh

npm i objectionjs-relationship --save

`

$3

`sh

yarn add objectionjs-relationship

`

Usage

#### Basic Use

`js
import {
ModelRelationshipFacade,
RelationshipEnum,
} from "objectionjs-relationship";

class Animal extends Model {
static tableName = "animals";
}

class Person extends Model {
static tableName = "persons";

/* Example 1: /
static relationMappings = new ModelRelationshipFacade(Person)
.belongsToOne(Animal)
.getRelationships();

/* Example 2: Or you can use the add function, sending the relation type /
static relationMappings = new ModelRelationshipFacade(Person)
.add(Animal, RelationshipEnum.BelongsToOneRelation)
.getRelationships();

// Result:
// static relationMappings: {
// animal: {
// relation: Model.BelongsToOneRelation,
// modelClass: Animal,
// join: {
// from: 'persons.animalId',
// to: 'animals.id'
// }
// }
// }
}
`

#### Chaining Relationships

`js
// Thoses Models are example models like Person or Animal.

/* Example 1 /
const relation = new ModelRelationshipFacade(Person)
.belongsToOne(Country)
.hasMany(Animal)
.hasOne(Contact)
.manyToMany(Activity)
.hasOneThrough(Vehicle);
.getRelationships();

/* Example 2 /
const relationWithAddFunction = new ModelRelationshipFacade(Person)
.add(Country, RelationshipEnum.BelongsToOneRelation)
.add(Animal, RelationshipEnum.HasManyRelation)
.add(Contact, RelationshipEnum.HasOneRelation)
.add(Activity, RelationshipEnum.ManyToManyRelation)
.add(Vehicle, RelationshipEnum.HasOneThroughRelation)
.getRelationships();

// Output:
// {
// country: {
// relation: Model.BelongsToOneRelation,
// modelClass: Country,
// join: {
// from: 'persons.countryId',
// to: 'countries.id'
// }
// },
// animals: {
// relation: Model.HasManyRelation,
// modelClass: Animal,
// join: {
// from: 'persons.id',
// to: 'animals.personId'
// }
// },
// contact: {
// relation: Model.HasOneRelation,
// modelClass: Contact,
// join: {
// from: 'persons.id',
// to: 'contacts.personId'
// }
// },
// activities: {
// relation: Model.ManyToManyRelation,
// modelClass: Activity,
// join: {
// from: 'persons.id',
// through: {
// from: 'activities_persons.personId',
// to: 'activities_persons.activityId'
// },
// to: 'activities.id'
// }
// },
// vehicle: {
// relation: Model.HasOneThroughRelation,
// modelClass: Vehicle,
// join: {
// from: 'persons.id',
// through: {
// from: 'persons_vehicles.personId',
// to: 'persons_vehicles.vehicleId'
// },
// to: 'vehicles.id'
// }
// }
// };
`

Options

IObjectionModelRelationshipAddConfig: This interface are the option that you can send to the add function and override the relation fields.

These options can be provided when instantiating the plugin.

#### Example 1

`js
import { ModelRelationshipFacade } from "objectionjs-relationship";

class Animal extends Model {
static tableName = "pets";
}

class Person extends Model {
static tableName = "owners";

static relationMappings = new ModelRelationshipFacade(Person)
.belongsToOne(Animal, {
relationName: "pet",
fromField: "petId",
fromTable: "owners",
toField: "superId",
toTable: "pets",
})
.getRelationships();

// Result:
// static relationMappings: {
// pet: {
// relation: Model.BelongsToOneRelation,
// modelClass: Animal,
// join: {
// from: 'owners.petId',
// to: 'pets.superId'
// }
// }
// }
}
`

#### Example 2

`js
import { ModelRelationshipFacade } from "objectionjs-relationship";

class Animal extends Model {
static tableName = "pets";
}

class Person extends Model {
static tableName = "owners";

static relationMappings = new ModelRelationshipFacade(Person)
.belongsToOne(Animal, {
relationName: "pet",
from: "owners.petId",
to: "pets.superId",
})
.getRelationships();

// Result:
// static relationMappings: {
// pet: {
// relation: Model.BelongsToOneRelation,
// modelClass: Animal,
// join: {
// from: 'owners.petId',
// to: 'pets.superId'
// }
// }
// }
}
`

The same can be done with _through_ relationship. Read the _IObjectionModelRelationshipAddConfig_ interface.

$3

You can send a options object to the getRelationships, witch one of the props is log

This was created for the purpose of testing. Log param can be a boolean or a function that will get an IObjectionModelRelationship as a parameter to do whatever the function wants to do with the data, like print with a custom logger or something.

`js
import {
ModelRelationshipFacade,
IObjectionModelRelationship,
} from "objectionjs-relationship";

class Animal extends Model {
static tableName = "animals";
}

class Person extends Model {
static tableName = "persons";

/* Example with default logger /
static relationMappings = new ModelRelationshipFacade(Person)
.belongsToOne(Animal)
.getRelationships({
log: true,
});

/* Example with custom log strategy /
static relationMappings = new ModelRelationshipFacade(Person)
.belongsToOne(Animal)
.getRelationships({
log: (relations: IObjectionModelRelationship) => {
// You can same logger or wathever you want
console.log(relations);
},
});
}
`

The terminal will show _(console.log as default)_:

`
{
animal: {
relation: Model.BelongsToOneRelation,
modelClass: Animal,
join: {
from: 'animals.personId',
to: 'persons.id'
}
}
}
`

Tests

Run the tests from the root directory:

`sh
npm test
`

Contributing & Development

$3

Found a bug or want to suggest something? Take a look first on the current and closed issues. If it is something new, please submit an issue.

$3

It will be awesome if you can help us evolve objectionjs-relationship. Want to help?

1. Fork it.

2. npm install.

3. Hack away.

4. Run the tests: npm test`.

5. Create a Pull Request.

License

This project is licensed under the MIT License - see the LICENSE file for details