✨ Transformers

pkg/configurator/deserializer.go

@@ -0,0 +1,10 @@
+package configurator
+
+import "encoding/json"
+
+func DeserializeOptions[T any](data any) T {
+	var out T
+	raw, _ := json.Marshal(data)
+	_ = json.Unmarshal(raw, &out)
+	return out
+}

pkg/configurator/router.go

@@ -0,0 +1,41 @@
+package configurator
+
+import (
+	"math/rand"
+)
+
+type AppConfig struct {
+	Sites []SiteConfig `json:"sites"`
+}
+
+func (v *AppConfig) LoadBalance(site SiteConfig) *UpstreamConfig {
+	idx := rand.Intn(len(site.Upstreams))
+
+	switch site.Upstreams[idx].GetType() {
+	case UpstreamTypeHypertext:
+		return &site.Upstreams[idx]
+	case UpstreamTypeFile:
+		// TODO Make this into hypertext configuration
+		return &site.Upstreams[idx]
+	default:
+		// Give him the null value when this configuration is invalid.
+		// Then we can print a log in the console to warm him.
+		return nil
+	}
+}
+
+type SiteConfig struct {
+	ID string `json:"id"`
+
+	Name         string                     `json:"name"`
+	Rules        []RouterRuleConfig         `json:"rules"`
+	Transformers []RequestTransformerConfig `json:"transformers"`
+	Upstreams    []UpstreamConfig           `json:"upstreams"`
+}
+
+type RouterRuleConfig struct {
+	Host    []string            `json:"host"`
+	Path    []string            `json:"path"`
+	Queries map[string]string   `json:"query"`
+	Headers map[string][]string `json:"headers"`
+}

pkg/configurator/struct.go

@@ -1,46 +0,0 @@
-package configurator
-
-import "strings"
-
-type AppConfig struct {
-	Sites []SiteConfig `json:"sites"`
-}
-
-type SiteConfig struct {
-	ID string `json:"id"`
-
-	Name      string             `json:"name"`
-	Rules     []RouterRuleConfig `json:"rules"`
-	Upstreams []UpstreamConfig   `json:"upstreams"`
-}
-
-type RouterRuleConfig struct {
-	Host    []string            `json:"host"`
-	Path    []string            `json:"path"`
-	Queries map[string]string   `json:"query"`
-	Headers map[string][]string `json:"headers"`
-}
-
-const (
-	UpstreamTypeFile      = "file"
-	UpstreamTypeHypertext = "hypertext"
-	UpstreamTypeUnknown   = "unknown"
-)
-
-type UpstreamConfig struct {
-	Name string `json:"name"`
-	URI  string `json:"uri"`
-}
-
-func (v *UpstreamConfig) GetType() string {
-	protocol := strings.SplitN(v.URI, "://", 2)[0]
-	switch protocol {
-	case "file":
-		return UpstreamTypeFile
-	case "http":
-	case "https":
-		return UpstreamTypeHypertext
-	}
-
-	return UpstreamTypeUnknown
-}

pkg/configurator/transformer.go

@@ -0,0 +1,58 @@
+package configurator
+
+import (
+	"github.com/gofiber/fiber/v2"
+	"regexp"
+	"strings"
+)
+
+type RequestTransformer struct {
+	ModifyRequest  func(options any, ctx *fiber.Ctx)
+	ModifyResponse func(options any, ctx *fiber.Ctx)
+}
+
+type RequestTransformerConfig struct {
+	Type    string `json:"type"`
+	Options any    `json:"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
+		}
+	}
+}
+
+var Transformers = map[string]RequestTransformer{
+	"replacePath": {
+		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))
+			}
+		},
+	},
+}

pkg/configurator/upstream.go

@@ -0,0 +1,46 @@
+package configurator
+
+import (
+	"fmt"
+	"github.com/gofiber/fiber/v2"
+	"github.com/samber/lo"
+	"strings"
+)
+
+const (
+	UpstreamTypeFile      = "file"
+	UpstreamTypeHypertext = "hypertext"
+	UpstreamTypeUnknown   = "unknown"
+)
+
+type UpstreamConfig struct {
+	Name string `json:"name"`
+	URI  string `json:"uri"`
+}
+
+func (v *UpstreamConfig) GetType() string {
+	protocol := strings.SplitN(v.URI, "://", 2)[0]
+	switch protocol {
+	case "file":
+		return UpstreamTypeFile
+	case "http":
+	case "https":
+		return UpstreamTypeHypertext
+	}
+
+	return UpstreamTypeUnknown
+}
+
+func (v *UpstreamConfig) MakeURI(ctx *fiber.Ctx) string {
+	var queries []string
+	for k, v := range ctx.Queries() {
+		queries = append(queries, fmt.Sprintf("%s=%s", k, v))
+	}
+
+	path := string(ctx.Request().URI().Path())
+	hash := string(ctx.Request().URI().Hash())
+
+	return v.URI + path +
+		lo.Ternary(len(queries) > 0, "?"+strings.Join(queries, "&"), "") +
+		lo.Ternary(len(hash) > 0, "#"+hash, "")
+}