mimetypes

README

go-mimetypes

There are many mime-type lookup tables. This one is ours.

Usage

package main

import (
	"flag"
	"fmt"
	"github.com/aaronland/go-mimetypes"
	"log"
	"os"
	"strings"
)

func main() {

	var extension = flag.Bool("extension", false, "Lookup mimetypes by extension")
	var mimetype = flag.Bool("mimetype", false, "Lookup extensions by mimetype")

	flag.Parse()

	for _, input := range flag.Args() {

		if *mimetype {
			t := mimetypes.TypesByExtension(input)
			fmt.Printf("%s\t%s\n", input, strings.Join(t, "\t"))
		} else if *extension {
			e := mimetypes.ExtensionsByType(input)
			fmt.Printf("%s\t%s\n", input, strings.Join(e, "\t"))
		} else {
			log.Fatal("Invalid lookup type")
		}
	}

	os.Exit(0)
}

Both the TypesByExtension and ExtensionsByType functions return a list of strings. Although it is unlikely that any given extension will return multiple mime-types it's certainly possible so that's what we solve. Handy helper functions to test for and return singletons are in the works.

When calling TypesByExtension you can pass extensions with or without a leading . character.

Tools

lookup

A simple command line tool to lookup mimetypes by extension or vice versa.

./bin/lookup -h
Usage of ./bin/wof-mimetype-lookup:
  -extension
    	Lookup mimetypes by extension
  -mimetype
    	Lookup extensions by mimetype

The output is a line-separated list containing a tab-separated list of input (extension or mimetype) followed by one or more matched. For example:

./bin/wof-mimetype-lookup -mimetype '.json' jpg
.json	application/json
jpg	image/jpeg

./bin/wof-mimetype-lookup -extension 'image/jpeg' 'image/gif'
image/jpeg	jpeg	jpg	jpe
image/gif	gif

Lookup tables

Lookup tables are generated from two sources: The Apache httpd web servers mime.types definition and a custom file to add things that aren't included in the first source.

Both sources are bundled with this repo in the tables subdirectory. To fetch a fresh version of the Apache mime.typs definitions run the apache-lookup-table Make target, like this:

make apache-lookup-table
curl -s -o tables/apache.txt 'https://svn.apache.org/viewvc/httpd/httpd/branches/2.2.x/docs/conf/mime.types?view=co'

To rebuild the (Go) lookup tables definitions run the lookup-tables Make target, like this:

make lookup-tables
if test -d pkg; then rm -rf pkg; fi
if test -d src; then rm -rf src; fi 
if test -d src; then rm -rf src; fi
mkdir -p src/github.com/whosonfirst/go-whosonfirst-mimetypes
cp *.go src/github.com/whosonfirst/go-whosonfirst-mimetypes/
cp -r lookup src/github.com/whosonfirst/go-whosonfirst-mimetypes/
if test -d vendor; then cp -r vendor/* src/; fi
if test -d lookup; then rm -rf lookup; fi
mkdir lookup
bin/wof-mimetype-build-lookup-tables -lookup extension tables/apache.txt tables/custom.txt > lookup/extension.go
bin/wof-mimetype-build-lookup-tables -lookup mimetype tables/apache.txt tables/custom.txt > lookup/mimetype.go
go fmt lookup/*.go
lookup/extension.go
lookup/mimetype.go
rm bin/wof-mimetype-build-lookup-tables

Note that the lookup-tables Make target does not rebuild the various binary tools (maybe it should) so you'll need to run the bin Make target to do that. There is a handy rebuild Make target do all of these things in go, if necessary, like this:

make rebuild
make[1]: Entering directory '/usr/local/whosonfirst/go-whosonfirst-mimetypes'
curl -s -o tables/apache.txt 'https://svn.apache.org/viewvc/httpd/httpd/branches/2.2.x/docs/conf/mime.types?view=co'
make[1]: Leaving directory '/usr/local/whosonfirst/go-whosonfirst-mimetypes'
make[1]: Entering directory '/usr/local/whosonfirst/go-whosonfirst-mimetypes'
if test -d pkg; then rm -rf pkg; fi
if test -d src; then rm -rf src; fi 
if test -d src; then rm -rf src; fi
mkdir -p src/github.com/whosonfirst/go-whosonfirst-mimetypes
cp *.go src/github.com/whosonfirst/go-whosonfirst-mimetypes/
cp -r lookup src/github.com/whosonfirst/go-whosonfirst-mimetypes/
if test -d vendor; then cp -r vendor/* src/; fi
if test -d lookup; then rm -rf lookup; fi
mkdir lookup
bin/wof-mimetype-build-lookup-tables -lookup extension tables/apache.txt tables/custom.txt > lookup/extension.go
bin/wof-mimetype-build-lookup-tables -lookup mimetype tables/apache.txt tables/custom.txt > lookup/mimetype.go
go fmt lookup/*.go
lookup/extension.go
lookup/mimetype.go
rm bin/wof-mimetype-build-lookup-tables
make[1]: Leaving directory '/usr/local/whosonfirst/go-whosonfirst-mimetypes'
make[1]: Entering directory '/usr/local/whosonfirst/go-whosonfirst-mimetypes'
if test -d pkg; then rm -rf pkg; fi
if test -d src; then rm -rf src; fi 
if test -d src; then rm -rf src; fi
mkdir -p src/github.com/whosonfirst/go-whosonfirst-mimetypes
cp *.go src/github.com/whosonfirst/go-whosonfirst-mimetypes/
cp -r lookup src/github.com/whosonfirst/go-whosonfirst-mimetypes/
if test -d vendor; then cp -r vendor/* src/; fi

See also

• https://golang.org/pkg/mime/#ExtensionsByType
• https://golang.org/pkg/net/http/#DetectContentType
• https://svn.apache.org/viewvc/httpd/httpd/branches/2.2.x/docs/conf/mime.types?view=co
• https://www.iana.org/assignments/media-types/media-types.xhtml

Documentation

Index

• func ExtensionsByType(t string) []string
• func TypesByExtension(e string) []string

Functions

func ExtensionsByType

func ExtensionsByType(t string) []string

func TypesByExtension

func TypesByExtension(e string) []string