loopback-component-flatstorage

loopback component for attaching to various cloud storage providers with ACL and relations functionality

LoopBack flatstorage component provides Node.js and REST APIs to manage binary file contents using pluggable storage providers, such as local file systems, Amazon S3, or Rackspace cloud files. It uses pkgcloud to support cloud-based storage services.

The module is only tested on amazon but potentially can work on all cloud providers - use at own risk! or better yet - contribute!

This module is based entirely on loopback-component-storage

The differences are:

• container (bucket) is defined at the data source level
• the model base should be 'PersistedModel' which enables relations and ACL
• the id of the model is the root 'folder'

API

Description	REST URI
List all files	GET /api/mystorage
List all files in a specified folder	GET /api/mystorage/myfolder
Get information for specified file within a specified folder	GET /api/mystorage/myfolder/files/myfile
Delete a specified file within a specified folder	DELETE /api/mystorage/myfolder/files/myfile
Download a specified file within a specified folder	GET /api/mystorage/myfolder/download/myfile
Upload one or more files into a specified container. The request body must use multipart/form-data which is the file input type HTML uses	POST /api/mystorage/myfolder/files/upload

Configuration

To create a model for images storage per user:

datasource.json:

{
  "ImagesS3": {
    "name": "ImagesS3",
    "provider": "amazon",
    "connector": "loopback-component-flatstorage",
    "container": "user-images",
    "region": "eu-central-1",
    "key": "<key>",
    "keyId": "<key-id>"
  }
}

images.json:

{
  "name": "Images",
  "plural": "Images",
  "base": "PersistedModel",
  "idInjection": false,
  "properties": {
    "userId": {
      "type": "string",
      "required": true,
      "id": true,
      "generated": false
    }
  },
  "validations": [],
  "relations": {
    "user": {
      "type": "belongsTo",
      "model": "User",
      "foreignKey": "userId",
      "required": true
    }
  },
  "acls": [
    {
      "accessType": "*",
      "principalType": "ROLE",
      "principalId": "$everyone",
      "permission": "DENY"
    },
    {
      "accessType": "*",
      "principalType": "ROLE",
      "principalId": "$owner",
      "permission": "ALLOW"
    }
  ],
  "methods": {}
}

user.json:

...
  "relations": {
    "images": {
      "type": "hasOne",
      "model": "Images",
      "foreignKey": "userId"
    }
  }
...

Nested Queries

The model can be used in nested queries.

To continue our example, we can enable the following nested rest api for a user to give him control over his files:

• /api/user/<user>/images/files/<my file>
• /api/user/<user>/images/download/<my file>
• /api/user/<user>/images/files/upload

To configure:

  app.models.User && app.models.Images && app.models.User.nestRemoting('images', {
    filterMethod: function (method, relation) {
      var matches = method.name.indexOf('removeFile') > -1 || method.name.indexOf('file') > -1 || method.name.indexOf('download') > -1 || method.name.indexOf('upload') > -1;
      if (matches) {
        return '__' + method.name + '__' + relation.name;
      }
    }
  });