ArangoFS

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