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    easen-models

    0.4.0 • Public • Published

    Easen Models

    Travis Code Climate Test Coverage NPM Downloads

    How to use

    Create your first model

    Firstly, you have to create your own model:

    const { createModel, types: t } = require('easen-models')
     
    const Post = createModel({
      id: t.int,
      title: t.string,
      published: t.bool,
      createdAt: t.date,
      updatedAt: t.date
    })

    Use model

    Secondly, just create instance of this model:

    const post = new Post({
      id: '10',
      title: 'Post title',
      published: 1,
      createdAt: '2017-01-01T15:00:00',
      updatedAt: Date.now()
    })

    Handle validation errors

    In case of current types, values will be transformed to correct type (e.g. id to int). When something will be wrong, ModelValidationError will be thrown, so you can handle errors:

    const { ModelValidationError } = require('easen-models')
     
    try {
      const post = new Post({
        id: '10',
        title: 'Post title',
        published: 1,
        createdAt: '2017-01-01T15:00:00',
        updatedAt: Date.now()
      })
    } catch (e) {
      if (e.name === 'ModelValidationError') {
        // Some values are wrong, you can look at additional errors at e.list
        // Or you can dump whole error with e.toJSON() method
      } else {
        // Rethrow errors not connected to validation
        throw e
      }
    }

    Prepare your own validators

    Behind the scenes, models are trying to instantiate values and checks for errors. Let see some examples of preparing your own validators:

    const { createModel, types: t } = require('easen-models')
     
    const Post = createModel({
      id: t.int.assert(v => v < 10, 'ID must be smaller than 10'),
      title: t.string.pass(v => v.toUpperCase()),
      published: t.assert(v => v === true, 'Post must be published'),
      likesPercentage: t.pass(parseFloat).pass(v => v * 100),
      slug: v => ('' + v).toLowerCase().replace(/[^a-z]/g, '-')
    })

    Validators/types are just simple functions, which can throw error. It means, that you can use any other libraries to use there. When Model will detect error thrown, it will throw ModelValidationError.

    Alternatively, you can use simple syntax with pass & assert helpers. Every validation included in easen-models allow chaining by default. pass is just passing a value to next function, assert will make assertion (check if passed function results with truthy value) and throw error if not. You can use these methods as many times in chain you want.

    Updating object

    You have to simply update a value - it will be automatically transformed. Everything is using getters & setters:

    const { createModel, types: t } = require('easen-models')
     
    const Post = createModel({
      id: t.int,
      title: t.string,
      published: t.bool,
      createdAt: t.date,
      updatedAt: t.date
    })
     
    const post = new Post({
      id: '10',
      title: 'Post title',
      published: 1,
      createdAt: '2017-01-01T15:00:00',
      updatedAt: Date.now()
    })
     
    console.log(post.createdAt) // instance of Date, 2017-01-01T15:00:00.000Z
     
    post.createdAt = '2015-01-01'
    console.log(post.createdAt) // instance of Date, 2015-01-01T00:00:00.000Z

    Getting raw object

    You can get copy of raw object using built-in function:

    const { raw } = require('easen-models')
    const value = raw(post)

    If you want to serialize object, you can simply use just JSON.stringify

    Development

    Mocha with Expect.js are used for tests, with Wallaby as additional runner for development. Code style standard is StandardJS.

    To do

    • Write unit tests
    • Extend description, improve documentation
    • Write oneOfType validator
    • Prepare table with available validators in README file

    Install

    npm i easen-models

    DownloadsWeekly Downloads

    50

    Version

    0.4.0

    License

    MIT

    Unpacked Size

    53.6 kB

    Total Files

    19

    Last publish

    Collaborators

    • rangoo