feat: rewriter layer

internal/proxy/director/layer/rewriter/layer.go

@@ -0,0 +1,84 @@
+package rewriter
+
+import (
+	"net/http"
+
+	proxy "forge.cadoles.com/Cadoles/go-proxy"
+	"forge.cadoles.com/Cadoles/go-proxy/wildcard"
+	"forge.cadoles.com/cadoles/bouncer/internal/proxy/director"
+	"forge.cadoles.com/cadoles/bouncer/internal/store"
+	"github.com/pkg/errors"
+	"gitlab.com/wpetit/goweb/logger"
+)
+
+const LayerType store.LayerType = "rewriter"
+
+type Layer struct{}
+
+func (l *Layer) LayerType() store.LayerType {
+	return LayerType
+}
+
+func (l *Layer) Middleware(layer *store.Layer) proxy.Middleware {
+	return func(next http.Handler) http.Handler {
+		fn := func(w http.ResponseWriter, r *http.Request) {
+			ctx := r.Context()
+
+			options, err := fromStoreOptions(layer.Options)
+			if err != nil {
+				logger.Error(ctx, "could not parse layer options", logger.E(errors.WithStack(err)))
+				http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
+
+				return
+			}
+
+			matches := wildcard.MatchAny(r.URL.String(), options.MatchURLs...)
+			if !matches {
+				next.ServeHTTP(w, r)
+
+				return
+			}
+
+			if err := l.applyRequestRules(r, options); err != nil {
+				logger.Error(ctx, "could not apply request rules", logger.E(errors.WithStack(err)))
+				http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
+
+				return
+			}
+
+			next.ServeHTTP(w, r)
+		}
+
+		return http.HandlerFunc(fn)
+	}
+}
+
+// ResponseTransformer implements director.ResponseTransformerLayer.
+func (l *Layer) ResponseTransformer(layer *store.Layer) proxy.ResponseTransformer {
+	return func(r *http.Response) error {
+		options, err := fromStoreOptions(layer.Options)
+		if err != nil {
+			return errors.WithStack(err)
+		}
+
+		matches := wildcard.MatchAny(r.Request.URL.String(), options.MatchURLs...)
+		if !matches {
+			return nil
+		}
+
+		if err := l.applyResponseRules(r, options); err != nil {
+			return errors.WithStack(err)
+		}
+
+		return nil
+	}
+}
+
+func New() *Layer {
+	return &Layer{}
+}
+
+var (
+	_ director.MiddlewareLayer          = &Layer{}
+	_ director.ResponseTransformerLayer = &Layer{}
+)