Feathers-graph-populate NPM

feathers-graph-populate

NOTE: This is the version for Feathers v5. For Feathers v4 use feathers-graph-populate v3

Add lightning fast, GraphQL-like populates to your FeathersJS API.

This project is built for FeathersJS. An open source web framework for building modern real-time applications.

Documentation

See https://feathers-graph-populate.netlify.app/ for full documentation

Getting Started

Define your relationships

The top-level keys in the populates represent the name of the relationship.

const populates = {
  posts: {
    service: 'posts',
    nameAs: 'posts',
    keyHere: '_id',
    keyThere: 'authorId',
    asArray: true,
    params: {}
  },
  comments: {
    service: 'comments',
    nameAs: 'comments',
    keyHere: '_id',
    keyThere: 'userId',
    asArray: true,
    params: {}
  },
  openTasks: {
    service: 'tasks',
    nameAs: 'openTasks',
    keyHere: '_id',
    keyThere: 'ownerIds',
    asArray: true,
    params: {
      query: {
        completedAt: null
      }
    }
  },
  role: {
    service: 'roles',
    nameAs: 'role',
    keyHere: 'roleId',
    keyThere: '_id',
    asArray: false,
    params: {}
  }
}

Options for each relationship

Each populate object must/can have the following properties:

Option	Description
`service`	The service for the relationshiprequiredType: `{String}`
`nameAs`	The property to be assigned to on this entry. It's recommended that you make the populate object key name match the `nameAs` property.requiredType: `{String}`
`keyHere`	The primary or secondary key for the current entryrequiredType: `{String}`
`keyThere`	The primary or secondary key for the referenced entry/entriesrequiredType: `{String}`
`asArray`	Is the referenced item a single entry or an array of entries?optional - default: `true`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: You can use this for adding a '$select' property or passing authentication and user data from 'context' to 'params' to restrict accesssoptional - default: `{}`Type: `{Object \| Function(params, context): undefined\|params}`

Create named queries to use from connected clients.

The top-level keys in the nameQueries object are the query names. Nested keys under the query name refer to the name of the relationship, found in the populates object from the previous code snippet.

const namedQueries = {
  withPosts: {
    posts: {}
  },
  postsWithComments: {
    posts: {
      comments: {}
    }
  },
  postsWithCommentsWithUser: {
    posts: {
      comments: {
        user:{}
      }
    }
  }
}

Register the hook

const { populate } = require('feathers-graph-populate')

const hooks = {
  after: {
    all: [
      populate({ populates, namedQueries })
    ]
  }
}

Perform Queries

Use a named query from a connected client:

feathersClient.service('users').find({
  query: {},
  $populateParams: {
    name: 'postsWithCommentsWithUser'
  }
})

Use a query object for internal requests. (named queries also work, internally):

app.service('users').find({
  query: {},
  $populateParams: {
    query: {
      posts: {
        comments: {
          user:{}
        }
      }
    }
  }
})

Handling Custom Client-Side Params

Since FeathersJS only supports passing params.query from client to server, by default, we need to let it know about the new $populateParams object. We can do this using the paramsForServer and paramsFromCLient hooks:

const { paramsForServer } = require('feathers-graph-populate')

feathersClient.hooks({
  before: {
    all: [
      paramsForServer('$populateParams')
    ]
  }
})

Now to allow the API server to receive the custom param:

const { paramsFromClient } = require('feathers-graph-populate')

feathersClient.hooks({
  before: {
    all: [
      paramsFromClient('$populateParams')
    ]
  }
})