Function NewConditionalHandler

context/handler.go:319–348

NewConditionalHandler returns a single Handler which can be registered as a middleware. Filter is just a type of Handler which returns a boolean. Handlers here should act like middleware, they should contain `ctx.Next` to proceed to the next handler of the chain. Those "handlers" are registered to t

(filter Filter, handlers ...Handler)

//
// Example can be found at: _examples/routing/conditional-chain.
func NewConditionalHandler(filter Filter, handlers ...Handler) Handler {
	return func(ctx *Context) {
		if filter(ctx) {
			// Note that we don't want just to fire the incoming handlers, we must make sure
			// that it won't break any further handler chain
			// information that may be required for the next handlers.
			//
			// The below code makes sure that this conditional handler does not break
			// the ability that iris provides to its end-devs
			// to check and modify the per-request handlers chain at runtime.
			currIdx := ctx.HandlerIndex(-1)
			currHandlers := ctx.Handlers()

			if currIdx == len(currHandlers)-1 {
				// if this is the last handler of the chain
				// just add to the last the new handlers and call Next to fire those.
				ctx.AddHandler(handlers...)
				ctx.Next()
				return
			}
			// otherwise insert the new handlers in the middle of the current executed chain and the next chain.
			newHandlers := append(currHandlers[:currIdx+1], append(handlers, currHandlers[currIdx+1:]...)...)
			ctx.SetHandlers(newHandlers)
			ctx.Next()
			return
		}
		// if not pass, then just execute the next.
		ctx.Next()
	}
}

// JoinHandlers returns a copy of "h1" and "h2" Handlers slice joined as one slice of Handlers.
func JoinHandlers(h1 Handlers, h2 Handlers) Handlers {