TUN-528: Move cloudflared into a separate repo

vendor/github.com/mholt/caddy/onevent/on.go

@@ -0,0 +1,68 @@
+package onevent
+
+import (
+	"strings"
+
+	"github.com/google/uuid"
+	"github.com/mholt/caddy"
+	"github.com/mholt/caddy/onevent/hook"
+)
+
+func init() {
+	// Register Directive.
+	caddy.RegisterPlugin("on", caddy.Plugin{Action: setup})
+}
+
+func setup(c *caddy.Controller) error {
+	config, err := onParse(c)
+	if err != nil {
+		return err
+	}
+
+	// Register Event Hooks.
+	c.OncePerServerBlock(func() error {
+		for _, cfg := range config {
+			caddy.RegisterEventHook("on-"+cfg.ID, cfg.Hook)
+		}
+		return nil
+	})
+
+	return nil
+}
+
+func onParse(c *caddy.Controller) ([]*hook.Config, error) {
+	var config []*hook.Config
+
+	for c.Next() {
+		cfg := new(hook.Config)
+
+		if !c.NextArg() {
+			return config, c.ArgErr()
+		}
+
+		// Configure Event.
+		event, ok := hook.SupportedEvents[strings.ToLower(c.Val())]
+		if !ok {
+			return config, c.Errf("Wrong event name or event not supported: '%s'", c.Val())
+		}
+		cfg.Event = event
+
+		// Assign an unique ID.
+		cfg.ID = uuid.New().String()
+
+		args := c.RemainingArgs()
+
+		// Extract command and arguments.
+		command, args, err := caddy.SplitCommandAndArgs(strings.Join(args, " "))
+		if err != nil {
+			return config, c.Err(err.Error())
+		}
+
+		cfg.Command = command
+		cfg.Args = args
+
+		config = append(config, cfg)
+	}
+
+	return config, nil
+}