Refactor Caddyfile adapter and module registration

Use piles from which to draw config values.

Module values can return their name, so now we can do two-way mapping
from value to name and name to value; whereas before we could only map
name to value. This was problematic with the Caddyfile adapter since
it receives values and needs to know the name to put in the config.

2 files changed, 20 insertions, 16 deletions

diff --git a/modules/caddyhttp/rewrite/caddyfile.go b/modules/caddyhttp/rewrite/caddyfile.go
index a067fe1..a977a72 100644
--- a/modules/caddyhttp/rewrite/caddyfile.go
+++ b/modules/caddyhttp/rewrite/caddyfile.go
@@ -15,24 +15,23 @@
 package rewrite
 
 import (
-	"github.com/caddyserver/caddy/v2/caddyconfig/caddyfile"
 	"github.com/caddyserver/caddy/v2/caddyconfig/httpcaddyfile"
+	"github.com/caddyserver/caddy/v2/modules/caddyhttp"
 )
 
-// UnmarshalCaddyfile sets up the handler from Caddyfile tokens. Syntax:
+func init() {
+	httpcaddyfile.RegisterHandlerDirective("rewrite", parseCaddyfile)
+}
+
+// parseCaddyfile sets up the handler from Caddyfile tokens. Syntax:
 //
 //     rewrite [<matcher>] <to>
 //
 // The <to> parameter becomes the new URI.
-func (rewr *Rewrite) UnmarshalCaddyfile(d *caddyfile.Dispenser) error {
-	for d.Next() {
-		rewr.URI = d.Val()
+func parseCaddyfile(h httpcaddyfile.Helper) (caddyhttp.MiddlewareHandler, error) {
+	var rewr Rewrite
+	for h.Next() {
+		rewr.URI = h.Val()
 	}
-	return nil
+	return rewr, nil
 }
-
-// Bucket returns the HTTP Caddyfile handler bucket number.
-func (rewr Rewrite) Bucket() int { return 1 }
-
-// Interface guard
-var _ httpcaddyfile.HandlerDirective = (*Rewrite)(nil)
diff --git a/modules/caddyhttp/rewrite/rewrite.go b/modules/caddyhttp/rewrite/rewrite.go
index ac113ff..f434a38 100644
--- a/modules/caddyhttp/rewrite/rewrite.go
+++ b/modules/caddyhttp/rewrite/rewrite.go
@@ -24,10 +24,7 @@ import (
 )
 
 func init() {
-	caddy.RegisterModule(caddy.Module{
-		Name: "http.handlers.rewrite",
-		New:  func() interface{} { return new(Rewrite) },
-	})
+	caddy.RegisterModule(Rewrite{})
 }
 
 // Rewrite is a middleware which can rewrite HTTP requests.
@@ -37,6 +34,14 @@ type Rewrite struct {
 	Rehandle bool   `json:"rehandle,omitempty"`
 }
 
+// CaddyModule returns the Caddy module information.
+func (Rewrite) CaddyModule() caddy.ModuleInfo {
+	return caddy.ModuleInfo{
+		Name: "http.handlers.rewrite",
+		New:  func() caddy.Module { return new(Rewrite) },
+	}
+}
+
 func (rewr Rewrite) ServeHTTP(w http.ResponseWriter, r *http.Request, next caddyhttp.Handler) error {
 	repl := r.Context().Value(caddy.ReplacerCtxKey).(caddy.Replacer)
 	var rehandleNeeded bool