init import

app/router/router.go

@@ -0,0 +1,162 @@
+/*
+ * Copyright 2026 Oleg Borodin <onborodin@gmail.com>
+ */
+package router
+
+import (
+	"fmt"
+	"net/http"
+	"regexp"
+)
+
+type MiddlewareFunc func(next Handler) Handler
+
+type Handler interface {
+	ServeHTTP(rctx *Context)
+}
+
+type HandlerFunc func(rctx *Context)
+
+func (handlerFunc HandlerFunc) ServeHTTP(rctx *Context) {
+	handlerFunc(rctx)
+}
+
+type Router struct {
+	headHandler  Handler
+	routeHandler *Selector
+}
+
+func NewRouter() *Router {
+	selector := NewSelector()
+	return &Router{
+		routeHandler: selector,
+		headHandler:  selector,
+	}
+}
+
+func (rout *Router) Use(mwFunc MiddlewareFunc) {
+	rout.headHandler = mwFunc(rout.headHandler)
+}
+
+func (rout *Router) Selector() *Selector {
+	return rout.routeHandler
+}
+
+func (rout *Router) AddRoute(method, path string, handlerFunc HandlerFunc) {
+	rout.routeHandler.AddRoute(method, path, handlerFunc)
+}
+
+func (rout *Router) Head(path string, handlerFunc HandlerFunc) {
+	rout.routeHandler.AddRoute("HEAD", path, handlerFunc)
+}
+
+func (rout *Router) Get(path string, handlerFunc HandlerFunc) {
+	rout.routeHandler.AddRoute("GET", path, handlerFunc)
+}
+
+func (rout *Router) Post(path string, handlerFunc HandlerFunc) {
+	rout.routeHandler.AddRoute("POST", path, handlerFunc)
+}
+
+func (rout *Router) Put(path string, handlerFunc HandlerFunc) {
+	rout.routeHandler.AddRoute("PUT", path, handlerFunc)
+}
+
+func (rout *Router) Patch(path string, handlerFunc HandlerFunc) {
+	rout.routeHandler.AddRoute("PATCH", path, handlerFunc)
+}
+
+func (rout *Router) Delete(path string, handlerFunc HandlerFunc) {
+	rout.routeHandler.AddRoute("DELETE", path, handlerFunc)
+}
+
+func (rout *Router) ServeHTTP(writer http.ResponseWriter, req *http.Request) {
+	rctx := NewContext(writer, req)
+	rout.headHandler.ServeHTTP(rctx)
+}
+
+func (rout *Router) NotFound(handlerFunc HandlerFunc) {
+	rout.routeHandler.notFound = handlerFunc
+}
+
+type Selector struct {
+	Routes   []*Route
+	notFound Handler
+}
+
+func NewSelector() *Selector {
+	notFound := HandlerFunc(func(ctx *Context) {
+		http.NotFound(ctx.Writer, ctx.Request)
+	})
+	return &Selector{
+		Routes:   make([]*Route, 0),
+		notFound: notFound,
+	}
+}
+
+const globalRoutePattern = `^%s$`
+
+func (hand *Selector) AddRoute(method, path string, handlerFunc HandlerFunc) error {
+	var err error
+	rawPath := path
+	path, err = pathCompiler(path)
+	if err != nil {
+		return err
+	}
+
+	path = fmt.Sprintf(globalRoutePattern, path)
+	re, err := regexp.Compile(path)
+	if err != nil {
+		return err
+	}
+
+	route := &Route{
+		Method:  method,
+		Path:    path,
+		RawPath: rawPath,
+		Handler: handlerFunc,
+		Regexp:  re,
+	}
+	hand.Routes = append(hand.Routes, route)
+	return err
+}
+
+func (hand *Selector) ServeHTTP(rctx *Context) {
+	realHandler := hand.notFound
+	for _, route := range hand.Routes {
+		match := route.Match(rctx.Request)
+		if !match {
+			continue
+		}
+		subvals := route.Regexp.FindStringSubmatch(rctx.Request.URL.Path)
+		subkeys := route.Regexp.SubexpNames()
+		for i, val := range subvals {
+			key := subkeys[i]
+			if key != "" {
+				rctx.PathMap[key] = val
+			}
+		}
+		realHandler = route.Handler
+		break
+	}
+	realHandler.ServeHTTP(rctx)
+}
+
+type Route struct {
+	Method  string
+	Regexp  *regexp.Regexp
+	Path    string
+	RawPath string
+	Handler HandlerFunc
+}
+
+func (route Route) Match(req *http.Request) bool {
+	if req.Method != route.Method {
+		return false
+	}
+	match := route.Regexp.MatchString(req.URL.Path)
+	if match {
+		return true
+	}
+	return false
+}