merge-items

Upserts documents (objects) into collections (arrays) by primary key

Getting started

npm i -S merge-items

``js
import mergeItems from 'merge-items';

mergeItems(source, items, options);
`

Example

`js
import mergeItems from 'merge-items';

const source = [
{id: 1, name: 'Foo'},
{id: 2, name: 'Bar'},
];
const items = [
{id: 1, name: 'FooFoo'},
{id: 3, name: 'Baz'},
];

mergeItems(source, items);
// => [
// {id: 1, name: 'FooFoo'},
// {id: 3, name: 'Baz'},
// ]

source;
// => [
// {id: 1, name: 'FooFoo'},
// {id: 2, name: 'Bar'},
// {id: 3, name: 'Baz'},
// ]
`

Options

$3

- type: string
- default: id

`js
const source = [];
const items = [
{_id: 'abc', name: 'foo'},
{_id: 'zxc', name: 'bar'},
];

mergeItems(source, items, {
primaryKey: '_id',
});
`

$3

- mapInsert(data) - maps items to be inserted (new items)
- mapUpdate(data) - maps items to be updated (existing items)
- mapUpsert(data, isNew) - maps all items

`js
class Person {
constructor(body) {
Object.assign(this, body);
}
}

const source = [];
const newPerson = {
name: 'Bob',
age: 20,
};

mergeItems(source, newPerson, {
mapUpsert: (data, isNew) => {
if (isNew) {
return new Person(data);
} else {
return data;
}
},
});
// => Person {
// name: 'Bob',
// age: 20,
// }
`

$3

- afterInsert(item, data) - invokes after item was inserted (new item)
- afterUpdate(item, data) - invokes after item was updated (existing item)
- afterUpsert(item, data, isNew) - always invokes

`js
const people = [];

class Person {
friendsIds = [];

constructor(body) {
Object.assign(this, body);
}

setFriends(friends) {
const newPeople = friends.map(f => {
return {
id: _.uniqueId(), // lodash function to generate unique ID
name: f,
};
})

mergeItems(people, newPeople);

this.friendsIds = newPeople.map(f => f.id);
}

getFriends() {
return people.filter(p => {
return this.friendsIds.includes(p.id);
});
}
}

const newPerson = {
id: 1,
name: 'Bob',
age: 20,
friends: ['Alice', 'Charlie'],
};

mergeItems(people, newPerson, {
mapUpsert: (data, isNew) => {
const {friends, ...body} = data;

if (isNew) {
return new Person(body);
} else {
return body;
}
},
afterUpsert: (person, data, isNew) => {
const {friends} = data;

person.setFriends(friends);
},
});
// => Person {
// id: 1,
// name: 'Bob',
// age: 20,
// friendsIds: [, ]
// }

people;
// => [
// Person {id: 1, name: 'Bob', age: 20, friendsIds: [, ]},
// Person {id: , name: 'Alice', friendsIds: []},
// Person {id: , name: 'Charlie', friendsIds: []},
// ]
``