set

func Middleware ¶

func Middleware[V any](key string, value V) func(ctx *velaros.Context)

Middleware creates middleware that sets a value on the message-level context. The value is set once when the middleware is created and reused for all messages. Values set at the message level only exist for the duration of that message's handler chain.

Use this when you want to share a constant value across handlers for each message.

Example:

router.Use(set.Middleware("apiVersion", "v1"))

router.Bind("/info", func(ctx *velaros.Context) {
    version := ctx.MustGet("apiVersion").(string)  // "v1"
    ctx.Send(map[string]string{"version": version})
})

See also: setfn.Middleware for dynamic values, setvalue.Middleware for pointer values.