Lighting fast Koa middleware for serving favicons, with built in support for all file formats. koa-icon caches favicon files in memeory for fast request response times and comes with build in ETag and Cache-control support, all with a simple to use API.

npm i koa-icon

const Koa = require('koa')
const favicon = require('koa-icon')
const app = new Koa()

app.use(favicon('./favicon.ico'))

app.listen(3000)

koa-icon comes with great default options making serving a favicon effortless. Simply provide the relative path to your favicon file and pass the middleware to Koa with a app.use(). It's recommended placing koa-icon above routers and other middleware that serve static files

app.use(favicon('./favicon.ico'))

All favicon file formats are supported by koa-icon. Use the options.type parameter to set the file format of your favicon

app.use(favicon('/favicon.png'), { type: 'png' })

Reading your favicon from file or requesting it from another source can be done manually by passing koa-icon a object of type Buffer

const icon = fs.readFileSync('./favicon.ico')
app.use(favicon(icon))

The Cash-Control HTTP header is used to specify browser cashing policies in both client requests and server responses.Use the options.maxAge perimeter to pass the number of seconds you wish for clients to cache the favicon

app.use(favicon('./favicon.ico'), { maxAge: 3600 }) // 1 hour

koa-icons default value for options.maxAge is 86400 (1 day), and will max out at 31536000 (1 year)

An ETag is a unique identifer assigned by the web server to a specific version of a resource then passed to the client within the HTTP ETag header of the response. When the resource is updated or changed a new unique ETag is generated. koa-icon uses the etag module to generate ETags.

Request freshness is determined by matching the current resources ETag against the ETag received from the If-None-Match HTTP request header. Fresh requests are responded with a status code of 304 (not modified) and stale requests are sent a status code of 200 along with the favicon in the response body. Support for ETags and freshness checking is built into koa-icon by default.

Contributors are welcome, feel free to submit a new pull request to help improve koa-icon.