npm package: @matg97/mongoose-plugin-autoinc
Description: This plugin allows you to auto-increment any field on any mongoose schema that you wish (forked mongoose-auto-increment in 2018).
Latest version: 1.1.10

# mongoose-plugin-autoinc
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---

This is a fork of [mongoose-auto-increment](https://github.com/chevex-archived/mongoose-auto-increment) which has not been maintained in a while. Also used fixes and changes from [dashride fork](https://github.com/Dashride/mongoose-auto-increment). This fork addresses the following issues:
- fix error `'required' is not valid for an index specification` for Mongoose 4
- does not require established connection for initialization **(deprecate `initialize()` method)**
- include Flowtype and Typescript declarations
- tested with Mongoose 5
- setup automatic package publishing on PR merge with Travis CI and [sematic-release](https://github.com/semantic-release/semantic-release)

## Getting Started

> npm install mongoose-plugin-autoinc

Once you have the plugin installed it is very simple to use. Just pass `autoIncrement` to the `plugin()` function on your schema.

````js
import mongoose from 'mongoose';
import { autoIncrement } from 'mongoose-plugin-autoinc';

const connection = mongoose.createConnection("mongodb://localhost/myDatabase");

const BookSchema = new mongoose.Schema({
  author: { type: Schema.Types.ObjectId, ref: 'Author' },
  title: String,
  genre: String,
  publishDate: Date
});

BookSchema.plugin(autoIncrement, 'Book');
const Book = connection.model('Book', BookSchema);
````

That's it. Now you can create book entities at will and they will have an `_id` field added of type `Number` and will automatically increment with each new document. Even declaring references is easy, just remember to change the reference property's type to `Number` instead of `ObjectId` if the referenced model is also using the plugin.

````js
const AuthorSchema = new mongoose.Schema({
  name: String
});

const BookSchema = new mongoose.Schema({
  author: { type: Number, ref: 'Author' },
  title: String,
  genre: String,
  publishDate: Date
});

BookSchema.plugin(autoIncrement, 'Book');
AuthorSchema.plugin(autoIncrement, 'Author');
````

### Want a field other than `_id`?

````js
BookSchema.plugin(autoIncrement, { model: 'Book', field: 'bookId' });
````

### Want that field to start at a different number than zero or increment by more than one?

````js
BookSchema.plugin(autoIncrement, {
  model: 'Book',
  field: 'bookId',
  startAt: 100,
  incrementBy: 100
});
````

Your first book document would have a `bookId` equal to `100`. Your second book document would have a `bookId` equal to `200`, and so on.

### Want to know the next number coming up?

````js
const Book = connection.model('Book', BookSchema);
Book.nextCount().then(count => {
  // count === 0 -> true
  const book = new Book();
  book.save(err1 => {
    // book._id === 0 -> true
    book.nextCount().then(count => {
      // count === 1 -> true
    });
  });
});
````

`nextCount` is both a static method on the model (`Book.nextCount(...)`) and an instance method on the document (`book.nextCount(...)`).

### Want to reset counter back to the start value?

````js
BookSchema.plugin(autoIncrement, {
  model: 'Book',
  field: 'bookId',
  startAt: 100
});

const Book = connection.model('Book', BookSchema),
book = new Book();

book.save(err => {
  // book._id === 100 -> true
  book.nextCount().then(count => {
    // count === 101 -> true
    book.resetCount().then(nextCount => {
      // nextCount === 100 -> true
    });
  });
});
````