Method ServeHTTP

modules/caddyhttp/map/map.go:124–172

(w http.ResponseWriter, r *http.Request, next caddyhttp.Handler)

}

func (h Handler) ServeHTTP(w http.ResponseWriter, r *http.Request, next caddyhttp.Handler) error {
	repl := r.Context().Value(caddy.ReplacerCtxKey).(*caddy.Replacer)

	// defer work until a variable is actually evaluated by using replacer's Map callback
	repl.Map(func(key string) (any, bool) {
		// return early if the variable is not even a configured destination
		destIdx := slices.Index(h.Destinations, key)
		if destIdx < 0 {
			return nil, false
		}

		input := repl.ReplaceAll(h.Source, "")

		// find the first mapping matching the input and return
		// the requested destination/output value
		for _, m := range h.Mappings {
			output := m.Outputs[destIdx]
			if output == nil {
				continue
			}
			outputStr := caddy.ToString(output)

			// evaluate regular expression if configured
			if m.re != nil {
				var result []byte
				matches := m.re.FindStringSubmatchIndex(input)
				if matches == nil {
					continue
				}
				result = m.re.ExpandString(result, outputStr, input, matches)
				return string(result), true
			}

			// otherwise simple string comparison
			if input == m.Input {
				return repl.ReplaceAll(outputStr, ""), true
			}
		}

		// fall back to default if no match or if matched nil value
		if len(h.Defaults) > destIdx {
			return repl.ReplaceAll(h.Defaults[destIdx], ""), true
		}

		return nil, true
	})

	return next.ServeHTTP(w, r)
}

// Mapping describes a mapping from input to outputs.
type Mapping struct {