go-middleware

Golang middleware collection

Middleware is value that have following type

func(http.HandlerFunc) http.HandlerFunc

In following example, testMiddleware is a middleware that adding some header to the response

var handler http.HandlerFunc = ...
var someMiddleware func(next http.HandlerFunc) http.HanlderFunc = ...

testMiddleware := func(next http.HandlerFunc) http.HanlderFunc {
  return func(w http.ResponseWriter, r *http.Request) {
    w.Header().Add("TestHeader", "test value")
    next(w, r)
  }
}

combinedHandler := someMiddleware(testMiddleware(handler))

Use httpchain package to chaining multiple middleware, so you can write

combinedHandler := httpchain.Chain(
  someMiddleware,
  testMiddleware,
  handler,
)