Route: Use a trie to register routes

framework/core.go

@@ -8,17 +8,17 @@ import (
 
 // Core is the core struct of the framework
 type Core struct {
-	router map[string]map[string]ControllerHandler
+	router map[string]*Trie
 }
 
 // NewCore initialize the Core.
 func NewCore() *Core {
-	getRouter := map[string]ControllerHandler{}
-	postRouter := map[string]ControllerHandler{}
-	putRouter := map[string]ControllerHandler{}
-	deleteRouter := map[string]ControllerHandler{}
+	getRouter := NewTrie()
+	postRouter := NewTrie()
+	putRouter := NewTrie()
+	deleteRouter := NewTrie()
 
-	router := map[string]map[string]ControllerHandler{}
+	router := map[string]*Trie{}
 	router["GET"] = getRouter
 	router["POST"] = postRouter
 	router["PUT"] = putRouter
@@ -30,25 +30,33 @@ func NewCore() *Core {
 // Get is a simple get router
 func (c *Core) Get(url string, handler ControllerHandler) {
 	upperUrl := strings.ToUpper(url)
-	c.router["GET"][upperUrl] = handler
+    if err := c.router["GET"].AddRouter(upperUrl, handler); err != nil{
+        log.Println(err)
+    }
 }
 
 // Post is a simple post router
 func (c *Core) Post(url string, handler ControllerHandler) {
 	upperUrl := strings.ToUpper(url)
-	c.router["POST"][upperUrl] = handler
+    if err := c.router["POST"].AddRouter(upperUrl, handler); err != nil{
+        log.Println(err)
+    }
 }
 
 // Put is a simple put router
 func (c *Core) Put(url string, handler ControllerHandler) {
 	upperUrl := strings.ToUpper(url)
-	c.router["PUT"][upperUrl] = handler
+    if err := c.router["PUT"].AddRouter(upperUrl, handler); err != nil{
+        log.Println(err)
+    }
 }
 
 // Delete is a simple delete router
 func (c *Core) Delete(url string, handler ControllerHandler) {
 	upperUrl := strings.ToUpper(url)
-	c.router["DELETE"][upperUrl] = handler
+    if err := c.router["DELETE"].AddRouter(upperUrl, handler); err != nil{
+        log.Println(err)
+    }
 }
 
 // FindRouteByRequest finds route using the request
@@ -62,8 +70,8 @@ func (c *Core) FindRouteByRequest(r *http.Request) ControllerHandler {
 		return nil
 	}
 
-	controller, ok := mapper[upperUri]
-	if !ok {
+	controller := mapper.FindRoute(upperUri)
+	if controller == nil {
 		log.Printf("URI %q is not recognized\n", r.URL.Path)
 		return nil
 	}

framework/trie.go

@@ -0,0 +1,154 @@
+package framework
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+)
+
+type Trie struct {
+	root *node
+}
+
+func NewTrie() *Trie {
+	return &Trie{root: newNode("")}
+}
+
+func (t *Trie) FindRoute(uri string) ControllerHandler {
+	uri = strings.TrimPrefix(uri, "/")
+	if uri == "" {
+		return t.root.handler
+	}
+
+	found := t.root.findRoute(uri)
+	if found == nil {
+		return nil
+	}
+
+	return found.handler
+}
+
+func (t *Trie) AddRouter(uri string, handler ControllerHandler) error {
+	uri = strings.TrimPrefix(uri, "/")
+	if uri == "" {
+		t.root.isLast = true
+		t.root.handler = handler
+		return nil
+	}
+
+	upperUri := strings.ToUpper(uri)
+	match := t.FindRoute(upperUri)
+	if match != nil {
+		// existing route
+		return fmt.Errorf("existing route for %q", uri)
+	}
+
+	// The route does not exist, add it to the tree
+	err := t.root.addRoute(upperUri, handler)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+type node struct {
+	isLast   bool
+	segment  string
+	handler  ControllerHandler
+	children []*node
+}
+
+func newNode(segment string) *node {
+	return &node{segment: segment}
+}
+
+func isWildcard(s string) bool {
+	return strings.HasPrefix(s, ":")
+}
+
+// /user/name
+// /user/:id/name
+// /user/3/name
+
+// findRoute finds the handler for the uri if exists.
+//
+// we suppose that uri passed here doesn't begin with "/"
+func (n *node) findRoute(uri string) *node {
+	splitted := strings.SplitN(uri, "/", 2)
+	splittedLen := len(splitted)
+
+	if isWildcard(splitted[0]) {
+		// input is a wildcard, check if this endpoint has already children
+		// if so, return the first one which is not nil.
+		nbChildren := len(n.children)
+		if nbChildren > 0 && n.children[0].segment != splitted[0] {
+			// several nodes exist, return the first one that is not nil
+			return n.children[0]
+		}
+	}
+
+	// try to find the value in childre
+	for _, child := range n.children {
+		if isWildcard(child.segment) || child.segment == splitted[0] {
+			if splittedLen == 1 {
+				// This is the last value, do the check and return
+				if child.isLast {
+					// if isLast, that means we have already registered the endpoint
+					return child
+				} else {
+					// otherwise, take it as not registered
+					return nil
+				}
+			}
+			// More segments to check
+			return child.findRoute(splitted[1])
+		}
+	}
+
+	// nothing found in the children
+	return nil
+}
+
+func (n *node) addRoute(uri string, handler ControllerHandler) error {
+	splitted := strings.SplitN(uri, "/", 2)
+	splittedLen := len(splitted)
+	isLast := splittedLen == 1
+
+	// try to find the value in childre
+	for _, child := range n.children {
+		if isWildcard(child.segment) || child.segment == splitted[0] {
+			if isLast {
+				// This is the last value, do the check and return
+				if child.isLast {
+					// if isLast, that means we have already registered the endpoint
+					return errors.New("node exists")
+				} else {
+					// otherwise, set the child
+					child.isLast = true
+					child.handler = handler
+					return nil
+				}
+			}
+			// More segments to check
+			return child.addRoute(splitted[1], handler)
+		}
+	}
+
+	// create a new node
+	new := newNode(splitted[0])
+	if isLast {
+		// this is the end
+		new.handler = handler
+		new.isLast = true
+		n.children = append(n.children, new)
+		return nil
+	}
+	// continue
+	new.isLast = false
+	err := new.addRoute(splitted[1], handler)
+	if err != nil {
+		return err
+	}
+	n.children = append(n.children, new)
+	return nil
+}

handlers.go

@@ -56,3 +56,28 @@ func FooControllerHandler(ctx *framework.Context) error {
 
 	return nil
 }
+
+func UserLoginController(ctx *framework.Context) error {
+	ctx.WriteJSON(http.StatusOK, "ok")
+	return nil
+}
+
+func SubjectDelController(ctx *framework.Context) error {
+	ctx.WriteJSON(http.StatusAccepted, "deleted")
+	return nil
+}
+
+func SubjectUpdateController(ctx *framework.Context) error {
+	ctx.WriteJSON(http.StatusAccepted, "updated")
+	return nil
+}
+
+func SubjectGetController(ctx *framework.Context) error {
+	ctx.WriteJSON(http.StatusAccepted, "got")
+	return nil
+}
+
+func SubjectListController(ctx *framework.Context) error {
+	ctx.WriteJSON(http.StatusAccepted, "list")
+	return nil
+}

routes.go

@@ -3,7 +3,13 @@ package main
 import "git.vinchent.xyz/vinchent/go-web/framework"
 
 func registerRouter(core *framework.Core) {
-	core.Get("/foo", FooControllerHandler)
-	barGroup := core.Group("/bar")
-	barGroup.Get("/foo", FooControllerHandler)
+	core.Get("/user/login", UserLoginController)
+
+	subjectApi := core.Group("/subject")
+	{
+		subjectApi.Delete("/:id", SubjectDelController)
+		subjectApi.Put("/:id", SubjectUpdateController)
+		subjectApi.Get("/:id", SubjectGetController)
+		subjectApi.Get("/list/all", SubjectListController)
+	}
 }