besticon

README

favicon-service (besticon)

This is a favicon service:

• Supports favicon.ico and apple-touch-icon.png
• Simple URL API
• Fallback icon generation
• Docker image & single binary download for easy hosting

Try out the demo at https://besticon-demo.herokuapp.com or find out how to deploy your own version right now.

What's this?

Websites used to have a favicon.ico, or not. With the introduction of the apple-touch-icon.png finding “the icon” for a website became more complicated. This service finds and — if necessary — generates icons for web sites.

API

GET /icon

This endpoint always returns an icon image for the given site — it redirects to an official icon if possible or creates and returns a fallback image if needed.

Parameter	Example	Description	Default
url	http://yelp.com		required
size	32..50..100	Desired size range (min..perfect..max) If no image of size perfect..max nor perfect..min can be found a fallback icon will be generated.	required
formats	png,ico	Comma-separated list of accepted image formats: png, ico, gif	png,ico,gif
fallback_icon_url	HTTP image URL	If provided, a redirect to this image will be returned in case no suitable icon could be found. This overrides the default fallback image behaviour.
fallback_icon_color	ff0000	If provided, letter icons will be colored with the hex value provided, rather than be grey, when no color can be found for any icon.

Examples

Input URL	Icon
https://besticon-demo.herokuapp.com/icon?url=yelp.com&size=32..50..120
https://besticon-demo.herokuapp.com/icon?url=yelp.com&size=64..64..120
https://besticon-demo.herokuapp.com/icon?url=yelp.com	size missing
https://besticon-demo.herokuapp.com/icon?url=httpbin.org/status/404&size=32..64..120
https://besticon-demo.herokuapp.com/icon?url=httpbin.org/status/404&size=32..64..120&fallback_icon_color=ff0000
https://besticon-demo.herokuapp.com/icon?url=фминобрнауки.рф&size=32..64..120

GET /allicons.json

This endpoint returns all icons for a given site.

Parameter	Example	Description	Default
url	http://yelp.com		required
formats	png,ico	Comma-separated list of accepted image formats: png, ico, gif	png,ico,gif

Examples

• https://besticon-demo.herokuapp.com/allicons.json?url=github.com
• https://besticon-demo.herokuapp.com/allicons.json?url=github.com&formats=png

Bugs & limitations

I tried hard to make this useful but please note there are some known limitations:

• Poor i18n support for letter icons (#13)

Feel free to file other bugs - and offer your help - at https://github.com/mat/besticon/issues.

Hosting

Simple options to host this service are, for example:

• Heroku: https://heroku.com/deploy
• Google Cloud Run: https://deploy.cloud.run

Docker

A docker image is available at https://hub.docker.com/r/matthiasluedtke/iconserver/, generated from the Dockerfile in this repo. I try to keep it updated for every release.

Note that this docker image is not used to run https://besticon-demo.herokuapp.com and therefore not well tested.

Monitoring

Prometheus metrics are exposed under /metrics. A Grafana dashboard config based on these metrics can be found in grafana-dashboard.json.

Server Executable

Download binaries

Binaries for some operating systems can be downloaded from https://github.com/mat/besticon/releases/latest

Build your own

If you have Go installed on your system you can use go get to fetch the source code and build the server:

$ go get -u github.com/mat/besticon/...

If you want to build executables for a different target operating system you can add the GOOS and GOARCH environment variables:

$ GOOS=linux GOARCH=amd64 go get -u github.com/mat/besticon/...

Running

To start the server on default port 8080 just do

$ iconserver

To use a different port use

$ PORT=80 iconserver

To listen on a different address (say localhost) use

$ ADDRESS=127.0.0.1 iconserver

To enable CORS headers you need to set CORS_ENABLED=true. Optionally, you can set additional environment variables which will be passed as options to the rs/cors middleware.

$ CORS_ENABLED=true iconserver

Now when you open http://localhost:8080/icons?url=instagram.com you should see something like

Configuration

There is not a lot to configure, but these environment variables exist

Variable	Description	Default Value
ADDRESS	HTTP server listen address	0.0.0.0
CACHE_SIZE_MB	Size for the groupcache, set to 0 to disable	32
CORS_ENABLED	Enables the rs/cors middleware	false
CORS_ALLOWED_HEADERS	Comma-separated, passed to middleware
CORS_ALLOWED_METHODS	Comma-separated, passed to middleware
CORS_ALLOWED_ORIGINS	Comma-separated, passed to middleware
CORS_ALLOW_CREDENTIALS	Boolean, passed to middleware
CORS_DEBUG	Boolean, passed to middleware
HOST_ONLY_DOMAINS		*
HTTP_CLIENT_TIMEOUT	Timeout used for HTTP requests. Supports units like ms, s, m.	5s
HTTP_MAX_AGE_DURATION	Cache duration for all dynamically generated HTTP responses. Supports units like ms, s, m.	720h (30 days)
HTTP_USER_AGENT	User-Agent used for HTTP requests	iPhone user agent string
POPULAR_SITES	Comma-separated list of domains used on /popular page	some random web sites
PORT	HTTP server port	8080
SERVER_MODE	Set to download to proxy downloads through besticon or redirect to let browser to download instead. (example at #40)	redirect

Contributors

• Erkie - https://github.com/erkie
• mmkal - https://github.com/mmkal
• kspearrin - https://github.com/kspearrin
• karl-ravn - https://github.com/karl-ravn

License

MIT License (MIT)

Copyright (c) 2015-2020 Matthias Lüdtke, Hamburg - https://github.com/mat

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Donate

If you find this useful and want to donate... you would make my day :-)