♻️ Move transformer to an isolated module

pkg/sign/transformers/module.go

@@ -0,0 +1,56 @@
+package transformers
+
+import (
+	"encoding/json"
+	"github.com/gofiber/fiber/v2"
+)
+
+// Definitions
+
+type RequestTransformer struct {
+	ModifyRequest  func(options any, ctx *fiber.Ctx)
+	ModifyResponse func(options any, ctx *fiber.Ctx)
+}
+
+type RequestTransformerConfig struct {
+	Type    string `json:"type" yaml:"type"`
+	Options any    `json:"options" yaml:"options"`
+}
+
+func (v *RequestTransformerConfig) TransformRequest(ctx *fiber.Ctx) {
+	for k, f := range Transformers {
+		if k == v.Type {
+			if f.ModifyRequest != nil {
+				f.ModifyRequest(v.Options, ctx)
+			}
+			break
+		}
+	}
+}
+
+func (v *RequestTransformerConfig) TransformResponse(ctx *fiber.Ctx) {
+	for k, f := range Transformers {
+		if k == v.Type {
+			if f.ModifyResponse != nil {
+				f.ModifyResponse(v.Options, ctx)
+			}
+			break
+		}
+	}
+}
+
+// Helpers
+
+func DeserializeOptions[T any](data any) T {
+	var out T
+	raw, _ := json.Marshal(data)
+	_ = json.Unmarshal(raw, &out)
+	return out
+}
+
+// Map of Transformers
+// Every transformer need to be mapped here so that they can get work.
+
+var Transformers = map[string]RequestTransformer{
+	"replacePath": ReplacePath,
+}

pkg/sign/transformers/replace_path.go

@@ -0,0 +1,24 @@
+package transformers
+
+import (
+	"github.com/gofiber/fiber/v2"
+	"regexp"
+	"strings"
+)
+
+var ReplacePath = RequestTransformer{
+	ModifyRequest: func(options any, ctx *fiber.Ctx) {
+		opts := DeserializeOptions[struct {
+			Pattern string `json:"pattern"`
+			Value   string `json:"value"`
+			Repl    string `json:"repl"` // Use when complex mode(regexp) enabled
+			Complex bool   `json:"complex"`
+		}](options)
+		path := string(ctx.Request().URI().Path())
+		if !opts.Complex {
+			ctx.Path(strings.ReplaceAll(path, opts.Pattern, opts.Value))
+		} else if ex := regexp.MustCompile(opts.Pattern); ex != nil {
+			ctx.Path(ex.ReplaceAllString(path, opts.Repl))
+		}
+	},
+}