Feathers-shallow-populate NPM

feathers-shallow-populate

Feathers Shallow Populate

The fastest FeathersJS hook for populating relational data.

Installation

npm install feathers-shallow-populate --save

Complete Example

Here's an example of using feathers-shallow-populate.

const { shallowPopulate } = require('feathers-shallow-populate')

const options = {
  include: [
    {
      service: 'tags',
      nameAs: 'tags',
      keyHere: 'tagIds',
      keyThere: '_id',
      asArray: true, // by default
      params: {} // by default
    },
    {
      service: 'tags',
      nameAs: 'tags',
      params: function(params, context) {
        return { 
          query: { 
            userId: this.userId,
            companyId: this.companyId
          } 
        }
      }
    }
  ]
}

app.service('posts').hooks({
  after: {
    all: shallowPopulate(options)
  }
});

Options for the hook

include (required) Can be one include object or an array of include objects. See table below
catchOnError (optional) Wether the hook continues populating, if an error occurs (e.g. because of missing authentication) or throws. Also can be set per include individually

Options per include

Option	Description
`service`	The service to referencerequiredType: `String`
`nameAs`	The property to be assigned to on this entryrequiredType: `String`
`keyHere`	The primary or secondary key for this entryrequired if `params` is not complex (most of the time)Type: `String`
`keyThere`	The primary or secondary key for the referenced entry/entriesrequired if `keyHere` is definedType: `String`
`asArray`	Is the referenced item a single entry or an array of entries?optional - default: `true`Type: `Boolean`
`requestPerItem`	Decided wether your `params` object/function runs against each item individually or bundled. Most of the time you don't need this.optional - default:- `false` (if `keyHere` and `keyThere` are defined)- `true` (if `keyHere` and `keyThere` are not defined)Type: `String`
`catchOnError`	Wether the hook continues populating, if an error occurs (e.g. because of missing authentication) or throws. Also can be set on the prior optionsoptional - default: `false`Type:: `Boolean`
`params`	Additional params to be passed to the underlying service.You can mutate the passed `params` object or return a newly created `params` object which gets merged deeply Merged deeply after the params are generated internally.ProTip #1: You can use this for adding a '$select' property or passing authentication and user data from 'context' to 'params' to restrict accesssProTip #2: If you don't define `keyHere` and `keyThere` or set `requestPerItem` to `true` the function has access to the `this` keyword being the individual item the request will be made for.ProTip #3: You can skip a `requestPerItem` if it returns `undefined`.ProTip #4: The hook whats for async functions!optional - default: `{}`Possible types:- `Object`: will be merged with params - simple requests- `Function(params, context, { path, service }) => params`: needs to return the `params` or a new one which gets merged deeply - more complex- `Function(params, context, { path, service }) => Promise<params>`- `[Object \| Function]`

Multiple Populates

const { shallowPopulate } = require('feathers-shallow-populate')

const options = {
  include: [
    {
      service: 'tags',
      nameAs: 'tags',
      keyHere: 'tagIds',
      keyThere: '_id',
      asArray: true,
      params: {}
    },
    {
      service: 'comments',
      nameAs: 'comments',
      keyHere: 'commentIds',
      keyThere: '_id',
      asArray: true,
      params: {}
    }
  ]
}

app.service('posts').hooks({
  after: {
    all: shallowPopulate(options)
  }
});

// result.data
[
  {
    id: 1,
    title: 'About Timothy',
    tagIds: [1, 2]
    tags: [
      {
        id: 1,
        name: 'tag 1'
      },
      {
        id: 2,
        name: 'tag 2'
      }
    ],
    commentIds: [3, 5],
    comments: [
      {
        id: 3,
        title: 'My first comment'
      },
      {
        id: 5,
        title: 'Another comment'
      }
    ]
  }
]

As Object

const { shallowPopulate } = require('feathers-shallow-populate')

const options = {
  include: {
    service: 'users',
    nameAs: 'publisher',
    keyHere: 'publisherId',
    keyThere: 'id',
    asArray: false,
    params: {}
  }
}

app.service('posts').hooks({
  after: {
    all: shallowPopulate(options)
  }
});

// result.data
[
  {
    id: 1,
    title: 'About Timothy',
    publisherId: 2,
    publisher: {
      id: 2,
      name: 'Timothy'
    }
  }
]

This will go through all the hook.data/hook.result and will create a single query to lookup the tags, it will then populate them back onto the data.