Header Guards

Header guards stop unsupported requests before handlers run.

Content type

app.Use(middleware.AllowContentType("application/json"))

Requests with another Content-Type return 415 Unsupported Media Type.

Zinc compares media types without parameters, so application/json; charset=utf-8 matches application/json.

Content encoding

app.Use(middleware.AllowContentEncoding("identity", "gzip"))

Missing Content-Encoding is treated as identity.

Use this before binders or body readers when an endpoint only accepts a known set of encodings.

Header routes

app.Use(middleware.RouteHeaders(middleware.HeaderRoute{
  Header: "X-Admin",
  Value:  "1",
  Middleware: func(c *zinc.Context) error {
    c.Set("admin", true)
    return c.Next()
  },
}))

RouteHeaders runs the first matching header middleware. If nothing matches, the request continues normally.

If Value is empty, any non-empty value for that header matches. Rules without a header or middleware are ignored.