filetype

Small Go package to infer the file and MIME type checking the magic numbers signature.

Features

• Supports a wide range of file types
• Provides file extension and proper MIME type
• File discovery by extension or MIME type
• File discovery by class (image, video, audio...)
• Bunch of helpers and shortcuts for easy file checking
• Pluggable by default: plug in new types and file matchers
• Simple and semantic API

Installation

go get gopkg.in/h2non/filetype.v0

Usage

import "gopkg.in/h2non/filetype.v0"

API

See Godoc reference.

Examples

Simple file type checking

package main

import (
  "fmt"
  "gopkg.in/h2non/filetype.v0"
  "io/ioutil"
)

func main() {
  buf, _ := ioutil.ReadFile("sample.jpg")

  kind, unkwown := filetype.Match(buf)
  if unkwown != nil {
    fmt.Printf("Unkwown: %s", unkwown)
    return
  }

  fmt.Printf("File type: %s. MIME: %s\n", kind.Extension, kind.MIME.Value)
}

Check type class

package main

import (
  "fmt"
  "gopkg.in/h2non/filetype.v0"
  "io/ioutil"
)

func main() {
  buf, _ := ioutil.ReadFile("sample.jpg")

  if filetype.IsImage(buf) {
    fmt.Println("Image file")
  } else {
    fmt.Println("Not an image")
  }
}

Supported type

package main

import (
  "fmt"
  "gopkg.in/h2non/filetype.v0"
)

func main() {
  // Check if file is supported by extension
  if filetype.IsSupported("jpg") {
    fmt.Println("Extension supported")
  } else {
    fmt.Println("Extension not supported")
  }

  // Check if file is supported by extension
  if filetype.IsMIMESupported("image/jpeg") {
    fmt.Println("MIME type supported")
  } else {
    fmt.Println("MIME type not supported")
  }
}

Add additional file type matchers

package main

import (
  "fmt"
  "gopkg.in/h2non/filetype.v0"
)

var fooType = filetype.NewType("foo", "foo/foo")

func fooMatcher(buf []byte, length int) bool {
  return length > 1 && buf[0] == 0x01 && buf[1] == 0x02
}

func main() {
  // Register the new matcher and its type
  filetype.AddMatcher(fooType, fooMatcher)

  // Check if the new type is supported by extension
  if filetype.IsSupported("foo") {
    fmt.Println("Suppored type: foo")
  }

  // Check if the new type is supported by MIME
  if filetype.IsMIMESupported("foo/foo") {
    fmt.Println("Suppored type: foo/foo")
  }

  // Try to match the file
  fooFile := []byte{0x01, 0x02}
  kind, _ := filetype.Match(fooFile)
  if kind == filetype.Unknown {
    fmt.Println("Unknown file type")
  } else {
    fmt.Printf("File type matched: %s\n", kind.Extension)
  }
}

Supported types

Image

• jpg - image/jpeg
• png - image/png
• gif - image/gif
• webp - image/webp
• cr2 - image/x-canon-cr2
• tif - image/tiff
• bmp - image/bmp
• jxr - image/vnd.ms-photo
• psd - image/vnd.adobe.photoshop
• ico - image/x-icon

Video

• mp4 - video/mp4
• m4v - video/x-m4v
• mkv - video/x-matroska
• webm - video/webm
• mov - video/quicktime
• avi - video/x-msvideo
• wmv - video/x-ms-wmv
• mpg - video/mpeg
• flv - video/x-flv

Audio

• mid - audio/midi
• mp3 - audio/mpeg
• m4a - audio/m4a
• ogg - audio/ogg
• flac - audio/x-flac
• wav - audio/x-wav

Archive

• epub - application/epub+zip
• zip - application/zip
• tar - application/x-tar
• rar - application/x-rar-compressed
• gz - application/gzip
• bz2 - application/x-bzip2
• 7z - application/x-7z-compressed
• xz - application/x-xz
• pdf - application/pdf
• exe - application/x-msdownload
• swf - application/x-shockwave-flash
• rtf - application/rtf
• eot - application/octet-stream
• ps - application/postscript
• sqlite - application/x-sqlite3

Font

• woff - application/font-woff
• woff2 - application/font-woff
• ttf - application/font-sfnt
• otf - application/font-sfnt

License

MIT - Tomas Aparicio