序
本文主要研究一下dubbo-go-proxy的Route
Route
dubbo-go-proxy/pkg/router/route.go
// Route defines the tree of router APIs
type Route struct {
lock sync.RWMutex
tree *avltree.Tree
wildcardTree *avltree.Tree
}
// NewRoute returns an empty router tree
func NewRoute() *Route {
return &Route{
tree: avltree.NewWithStringComparator(),
wildcardTree: avltree.NewWithStringComparator(),
}
}
Route定义了lock、tree、wildcardTree属性,其NewRoute方法用于创建Route
PutAPI
dubbo-go-proxy/pkg/router/route.go
// PutAPI puts an api into the resource
func (rt *Route) PutAPI(api router.API) error {
lowerCasePath := strings.ToLower(api.URLPattern)
node, ok := rt.findNode(lowerCasePath)
rt.lock.Lock()
defer rt.lock.Unlock()
if !ok {
wildcard := strings.Contains(lowerCasePath, constant.PathParamIdentifier)
rn := &Node{
fullPath: lowerCasePath,
methods: map[config.HTTPVerb]*config.Method{api.Method.HTTPVerb: &api.Method},
wildcard: wildcard,
headers: api.Headers,
}
if wildcard {
rt.wildcardTree.Put(lowerCasePath, rn)
}
rt.tree.Put(lowerCasePath, rn)
return nil
}
return node.putMethod(api.Method, api.Headers)
}
PutAPI方法根据lowerCasePath去查找node,若没有找到则加锁创建Node,然后放到tree中,若是path是wildcard的则也会加入到wildcardTree中;如果有找到则执行node.putMethod(api.Method, api.Headers)
UpdateAPI
dubbo-go-proxy/pkg/router/route.go
// UpdateAPI update the api method in the existing router node
func (rt *Route) UpdateAPI(api router.API) error {
node, found := rt.findNode(api.URLPattern)
if found {
if _, ok := node.methods[api.Method.HTTPVerb]; ok {
rt.lock.Lock()
defer rt.lock.Unlock()
node.methods[api.Method.HTTPVerb] = &api.Method
}
}
return nil
}
UpdateAPI方法先根据api.URLPattern查找node,若找不到返回nil,找到的话再去找node.methods[api.Method.HTTPVerb],若找到则将api.Method赋值给node.methods[api.Method.HTTPVerb]
FindAPI
dubbo-go-proxy/pkg/router/route.go
// FindAPI returns the api that meets the
func (rt *Route) FindAPI(fullPath string, httpverb config.HTTPVerb) (*router.API, bool) {
if n, found := rt.findNode(fullPath); found {
rt.lock.RLock()
defer rt.lock.RUnlock()
if method, ok := n.methods[httpverb]; ok {
return &router.API{
URLPattern: n.fullPath,
Method: *method,
Headers: n.headers,
}, ok
}
}
return nil, false
}
FindAPI方法先通过findNode找node,再通过node.methods[httpverb]找method
findNode
dubbo-go-proxy/pkg/router/route.go
func (rt *Route) findNode(fullPath string) (*Node, bool) {
lowerPath := strings.ToLower(fullPath)
var n interface{}
var found bool
if n, found = rt.searchWildcard(lowerPath); !found {
rt.lock.RLock()
defer rt.lock.RUnlock()
if n, found = rt.tree.Get(lowerPath); !found {
return nil, false
}
}
return n.(*Node), found
}
findNode方法通过searchWildcard来查找node,找不到则从node的tree.Get方法查找
searchWildcard
dubbo-go-proxy/pkg/router/route.go
func (rt *Route) searchWildcard(fullPath string) (*Node, bool) {
rt.lock.RLock()
defer rt.lock.RUnlock()
wildcardPaths := rt.wildcardTree.Keys()
for _, p := range wildcardPaths {
if wildcardMatch(p.(string), fullPath) != nil {
n, ok := rt.wildcardTree.Get(p)
return n.(*Node), ok
}
}
return nil, false
}
searchWildcard方法遍历wildcardTree.Keys(),挨个执行wildcardMatch,若匹配到则通过wildcardTree.Get(p)来获取node
小结
Route定义了lock、tree、wildcardTree属性,其NewRoute方法用于创建Route;它提供了PutAPI、UpdateAPI、FindAPI等方法;里头实现使用的是avltree.Tree。