router.go

package axisapi

import (
	"log"
	"net/http"
	"strings"
)

type router struct {
	roots    map[string]*node // 添加路由前缀树
	handlers map[string]HandleFunc
}

func newRouter() *router {
	return &router{
		roots:    make(map[string]*node),
		handlers: make(map[string]HandleFunc),
	}
}

// 以/分割路由,并且只允许*在最后
func parsePattern(pattern string) []string {
	p := strings.Split(pattern, "/")
	parts := make([]string, 0)
	for _, item := range p {
		if item != "" {
			parts = append(parts, item)
			// only allowed one '*'
			if item[0] == '*' {
				break
			}
		}
	}
	return parts
}

func (r *router) addRoute(method string, pattern string, handler HandleFunc) {
	log.Printf("Router %4s - %s", method, pattern)
	parts := parsePattern(pattern)
	key := method + "|" + pattern
	_, ok := r.roots[method]
	if !ok {
		r.roots[method] = &node{}
	}
	r.roots[method].insert(pattern, parts, 0)
	r.handlers[key] = handler
}

func (r *router) getRouter(method string, path string) (*node, map[string]string) {
	searchParts := parsePattern(path)
	params := make(map[string]string)
	root, ok := r.roots[method]
	if !ok {
		return nil, nil
	}
	n := root.search(searchParts, 0)
	if n != nil {
		parts := parsePattern(n.pattern)
		// 获取动态路由中的参数如/a/:name - /a/boo --> name=boo
		for index, part := range parts {
			if part[0] == ':' {
				params[part[1:]] = searchParts[index]
			}
			// *temp/a/b --> temp = /a/b
			if part[0] == '*' && len(part) > 1 {
				params[part[1:]] = strings.Join(searchParts[index:], "/")
				break
			}
		}
		return n, params
	}
	return nil, nil
}

func (r *router) handle(ctx *Context) {
	// 设置中间件（所有handle function）
	n, params := r.getRouter(ctx.Method, ctx.Path)
	if n != nil {
		ctx.Params = params
		key := ctx.Method + "|" + n.pattern
		// 处理函数（不是中间件）最后执行
		ctx.handlers = append(ctx.handlers, r.handlers[key])
	} else {
		ctx.handlers = append(ctx.handlers, func(ctx *Context) {
			ctx.String(http.StatusNotFound, "404 NOT FOUND: %s\n", ctx.Path)
		})
	}
	// 执行所有handle function
	ctx.Next()
}