/arangofs

A file storage system for ArangoDB

Primary LanguageJavaScriptApache License 2.0Apache-2.0

ArangoFS

npm version license

ArangoFS is a library for storing files using an ArangoDB database.

Using RethinkDB? Try rethinkdb-regrid
Using SQL? Try SQLGrid

Features

  • Efficient - Save space with automatic inline deduplication.
  • Easy - Read and write files as if they were on disk with developer friendly APIs.
  • Revisions - Keeps multiple versions of files.
  • Byte-range Capable - Supports byte ranges to allow for streaming media.
  • Consistent - Sha256 hashes are calculated when the file is written, and verified when read back out.

View the Changelog


Special thanks to Arthur Andrew Medical for sponsoring this project.

Arthur Andrew Medical manufactures products with ingredients that have extensive clinical research for safety and efficacy. They specialize in Enzymes, Probiotics and Antioxidants.


Installation

Supports node v10.12+

npm install --save @internalfx/arangofs

TL;DR

var ArangoFS = require('@internalfx/arangofs')

var bucket = ArangoFS()

// initBucket creates tables and indexes if they don't exist, returns a promise.
bucket.initBucket().then(function () {
  // We are now ready to read and write files
})

API Documentation

ArangoFS([connectionOptions, bucketOptions])

Parameters
key default type description
connectionOptions {} Object connectionOptions is used to create an ArangoDB connection, see parameters below.
bucketOptions {} Object Optional parameters listed below
connectionOptions
key default type description
url undefined String Server URL
database undefined String Database name.
username undefined String
password undefined String
bucketOptions
key default type description
bucketName arangofs String The name of the bucket. Table names are prefixed by this.
path undefined String The folder where blobs are stored
returns

Bucket instance

Description

Creates a new ArangoFS bucket instance.

Example
var ArangoFS = require('@internalfx/arangofs')

var bucket = ArangoFS({url: 'http://localhost:8529', database: 'test'}, {path: '/tmp/blobs'})

initBucket()

Parameters

none

returns

Promise

Description

Verifies required tables and indexes exist and will create them if missing.

Example
bucket.initBucket().then(function () {
  // bucket is ready for use.....
})

writeFile(options)

Options
key default type description
filename required String The name of the file.
buffer required Buffer A buffer of file contents.
returns

Promise

Description

Returns a promise that resolves to the newly written file.

Example
let fileBuffer = fs.readFileSync('./myVid.mp4')

let newFile = await bucket.writeFile({filename: '/videos/myVid.mp4', buffer: fileBuffer})

createWriteStream(options)

Options
key default type description
filename required String The name of the file.
returns

WriteStream

Description

Returns a write stream for storing a file in ArangoFS.

Example
var writeStream = bucket.createWriteStream({
  filename: '/videos/myVid.mp4'
})

writeStream.on('finish', function () {
  // File is now stored in ArangoFS
})

fs.createReadStream('./myVid.mp4').pipe(writeStream)

getFile(options)

Gets only the files metadata.

Options
key default type description
id Null String The id of the file to retrieve.
filename Null String Ignored if id != null. The filename of the file to retrieve
revision -1 Number Ignored if id != null. The revision of the file to retrieve. If multiple files are uploaded under the same filename they are considered revisions. This may be a positive or negative number. (see chart below) Passing 'all' will return an array of all revisions.
How revision numbers work

If there are five versions of a file, the below chart would be the revision numbers

Number Description
0 or -5 The original file
1 or -4 The first revision
2 or -3 The second revision
3 or -2 The second most recent revision
4 or -1 The most recent revision
Description

If revision is a number a promise will be returned that resolves to an object of the files information. If revision is 'all' a promise will be returned that resolves to an array of all file revisions.

Example
let file1 = await bucket.getFile({id: 'ca608825-15c0-44b5-9bef-3ccabf061bab'})
let file2 = await bucket.getFile({filename: 'catVideo.mp4', revision: 2})
let allVersionsOfCatVideo = await bucket.getFile({filename: 'catVideo.mp4', revision: 'all'})

readFile(options)

Gets the files metadata and contents.

Options
key default type description
id Null String The id of the file to retrieve.
filename Null String Ignored if id != null. The filename of the file to retrieve
revision -1 Number/String Ignored if id != null. The revision of the file to retrieve. If multiple files are uploaded under the same filename they are considered revisions. This may be a positive or negative number. (see chart below) Passing 'all' will return an array of all revisions.
seekStart Null Number The start of the byte range.
seekEnd Null Number The end of the byte range. If omitted the stream will continue to the end of file.
How revision numbers work

If there are five versions of a file, the below chart would be the revision numbers

Number Description
0 or -5 The original file
1 or -4 The first revision
2 or -3 The second revision
3 or -2 The second most recent revision
4 or -1 The most recent revision
Description

If revision is a number a promise will be returned that resolves to an object of the files information and contents. If revision is 'all' a promise will be returned that resolves to an array of all file revisions and contents.

Example
let file1 = await bucket.readFile({id: 'ca608825-15c0-44b5-9bef-3ccabf061bab'})
let file2 = await bucket.readFile({filename: 'catVideo.mp4', revision: 2})
let allVersionsOfCatVideo = await bucket.readFile({filename: 'catVideo.mp4', revision: 'all'})

createReadStream(options)

Options
key default type description
id required String The id of the file to retrieve
seekStart Null Number The start of the byte range.
seekEnd Null Number The end of the byte range. If omitted the stream will continue to the end of file.
returns

ReadStream

Description

Returns a read stream for reading a file from ArangoFS.

Example
var readStream = bucket.createReadStream({id: 'ca608825-15c0-44b5-9bef-3ccabf061bab'})

readStream.pipe(fs.createWriteStream('./mySavedVideo.mp4'))

deleteFileById(options)

Options
key default type description
id required String The id of the file to delete
returns

Boolean, true if successful, false otherwise.

Description

Deletes a file from ArangoFS.

Example
let result = await arangoFS.deleteFileById({id: 1})

deleteFileByName(options)

Options
key default type description
filename Null String The filename of the file to delete
revision all Number The revision of the file to delete. If multiple files are uploaded under the same filename they are considered revisions. This may be a positive or negative number (see chart below). The default is to delete all revisions.
How revision numbers work

If there are five versions of a file, the below chart would be the revision numbers

Number Description
0 or -5 The original file
1 or -4 The first revision
2 or -3 The second revision
3 or -2 The second most recent revision
4 or -1 The most recent revision
returns

Boolean, true if successful, false otherwise.

Description

Deletes a file from ArangoFS.

Example
let result = await arangoFS.deleteFileByName({filename: 'video.mp4'})
// Deletes all revisions of video.mp4

let result = await arangoFS.deleteFileByName({filename: 'video.mp4', revision: -1})
// Deletes only the most recent revision of video.mp4

Thanks

Videos used in tests acquired from Pexels