mirror of
https://github.com/42wim/matterbridge.git
synced 2024-11-25 04:02:03 -08:00
567 lines
16 KiB
Go
567 lines
16 KiB
Go
package echo
|
|
|
|
import (
|
|
"net/http"
|
|
)
|
|
|
|
type (
|
|
// Router is the registry of all registered routes for an `Echo` instance for
|
|
// request matching and URL path parameter parsing.
|
|
Router struct {
|
|
tree *node
|
|
routes map[string]*Route
|
|
echo *Echo
|
|
}
|
|
node struct {
|
|
kind kind
|
|
label byte
|
|
prefix string
|
|
parent *node
|
|
staticChildren children
|
|
ppath string
|
|
pnames []string
|
|
methodHandler *methodHandler
|
|
paramChild *node
|
|
anyChild *node
|
|
// isLeaf indicates that node does not have child routes
|
|
isLeaf bool
|
|
// isHandler indicates that node has at least one handler registered to it
|
|
isHandler bool
|
|
}
|
|
kind uint8
|
|
children []*node
|
|
methodHandler struct {
|
|
connect HandlerFunc
|
|
delete HandlerFunc
|
|
get HandlerFunc
|
|
head HandlerFunc
|
|
options HandlerFunc
|
|
patch HandlerFunc
|
|
post HandlerFunc
|
|
propfind HandlerFunc
|
|
put HandlerFunc
|
|
trace HandlerFunc
|
|
report HandlerFunc
|
|
}
|
|
)
|
|
|
|
const (
|
|
staticKind kind = iota
|
|
paramKind
|
|
anyKind
|
|
|
|
paramLabel = byte(':')
|
|
anyLabel = byte('*')
|
|
)
|
|
|
|
func (m *methodHandler) isHandler() bool {
|
|
return m.connect != nil ||
|
|
m.delete != nil ||
|
|
m.get != nil ||
|
|
m.head != nil ||
|
|
m.options != nil ||
|
|
m.patch != nil ||
|
|
m.post != nil ||
|
|
m.propfind != nil ||
|
|
m.put != nil ||
|
|
m.trace != nil ||
|
|
m.report != nil
|
|
}
|
|
|
|
// NewRouter returns a new Router instance.
|
|
func NewRouter(e *Echo) *Router {
|
|
return &Router{
|
|
tree: &node{
|
|
methodHandler: new(methodHandler),
|
|
},
|
|
routes: map[string]*Route{},
|
|
echo: e,
|
|
}
|
|
}
|
|
|
|
// Add registers a new route for method and path with matching handler.
|
|
func (r *Router) Add(method, path string, h HandlerFunc) {
|
|
// Validate path
|
|
if path == "" {
|
|
path = "/"
|
|
}
|
|
if path[0] != '/' {
|
|
path = "/" + path
|
|
}
|
|
pnames := []string{} // Param names
|
|
ppath := path // Pristine path
|
|
|
|
if h == nil && r.echo.Logger != nil {
|
|
// FIXME: in future we should return error
|
|
r.echo.Logger.Errorf("Adding route without handler function: %v:%v", method, path)
|
|
}
|
|
|
|
for i, lcpIndex := 0, len(path); i < lcpIndex; i++ {
|
|
if path[i] == ':' {
|
|
j := i + 1
|
|
|
|
r.insert(method, path[:i], nil, staticKind, "", nil)
|
|
for ; i < lcpIndex && path[i] != '/'; i++ {
|
|
}
|
|
|
|
pnames = append(pnames, path[j:i])
|
|
path = path[:j] + path[i:]
|
|
i, lcpIndex = j, len(path)
|
|
|
|
if i == lcpIndex {
|
|
// path node is last fragment of route path. ie. `/users/:id`
|
|
r.insert(method, path[:i], h, paramKind, ppath, pnames)
|
|
} else {
|
|
r.insert(method, path[:i], nil, paramKind, "", nil)
|
|
}
|
|
} else if path[i] == '*' {
|
|
r.insert(method, path[:i], nil, staticKind, "", nil)
|
|
pnames = append(pnames, "*")
|
|
r.insert(method, path[:i+1], h, anyKind, ppath, pnames)
|
|
}
|
|
}
|
|
|
|
r.insert(method, path, h, staticKind, ppath, pnames)
|
|
}
|
|
|
|
func (r *Router) insert(method, path string, h HandlerFunc, t kind, ppath string, pnames []string) {
|
|
// Adjust max param
|
|
paramLen := len(pnames)
|
|
if *r.echo.maxParam < paramLen {
|
|
*r.echo.maxParam = paramLen
|
|
}
|
|
|
|
currentNode := r.tree // Current node as root
|
|
if currentNode == nil {
|
|
panic("echo: invalid method")
|
|
}
|
|
search := path
|
|
|
|
for {
|
|
searchLen := len(search)
|
|
prefixLen := len(currentNode.prefix)
|
|
lcpLen := 0
|
|
|
|
// LCP - Longest Common Prefix (https://en.wikipedia.org/wiki/LCP_array)
|
|
max := prefixLen
|
|
if searchLen < max {
|
|
max = searchLen
|
|
}
|
|
for ; lcpLen < max && search[lcpLen] == currentNode.prefix[lcpLen]; lcpLen++ {
|
|
}
|
|
|
|
if lcpLen == 0 {
|
|
// At root node
|
|
currentNode.label = search[0]
|
|
currentNode.prefix = search
|
|
if h != nil {
|
|
currentNode.kind = t
|
|
currentNode.addHandler(method, h)
|
|
currentNode.ppath = ppath
|
|
currentNode.pnames = pnames
|
|
}
|
|
currentNode.isLeaf = currentNode.staticChildren == nil && currentNode.paramChild == nil && currentNode.anyChild == nil
|
|
} else if lcpLen < prefixLen {
|
|
// Split node
|
|
n := newNode(
|
|
currentNode.kind,
|
|
currentNode.prefix[lcpLen:],
|
|
currentNode,
|
|
currentNode.staticChildren,
|
|
currentNode.methodHandler,
|
|
currentNode.ppath,
|
|
currentNode.pnames,
|
|
currentNode.paramChild,
|
|
currentNode.anyChild,
|
|
)
|
|
// Update parent path for all children to new node
|
|
for _, child := range currentNode.staticChildren {
|
|
child.parent = n
|
|
}
|
|
if currentNode.paramChild != nil {
|
|
currentNode.paramChild.parent = n
|
|
}
|
|
if currentNode.anyChild != nil {
|
|
currentNode.anyChild.parent = n
|
|
}
|
|
|
|
// Reset parent node
|
|
currentNode.kind = staticKind
|
|
currentNode.label = currentNode.prefix[0]
|
|
currentNode.prefix = currentNode.prefix[:lcpLen]
|
|
currentNode.staticChildren = nil
|
|
currentNode.methodHandler = new(methodHandler)
|
|
currentNode.ppath = ""
|
|
currentNode.pnames = nil
|
|
currentNode.paramChild = nil
|
|
currentNode.anyChild = nil
|
|
currentNode.isLeaf = false
|
|
currentNode.isHandler = false
|
|
|
|
// Only Static children could reach here
|
|
currentNode.addStaticChild(n)
|
|
|
|
if lcpLen == searchLen {
|
|
// At parent node
|
|
currentNode.kind = t
|
|
currentNode.addHandler(method, h)
|
|
currentNode.ppath = ppath
|
|
currentNode.pnames = pnames
|
|
} else {
|
|
// Create child node
|
|
n = newNode(t, search[lcpLen:], currentNode, nil, new(methodHandler), ppath, pnames, nil, nil)
|
|
n.addHandler(method, h)
|
|
// Only Static children could reach here
|
|
currentNode.addStaticChild(n)
|
|
}
|
|
currentNode.isLeaf = currentNode.staticChildren == nil && currentNode.paramChild == nil && currentNode.anyChild == nil
|
|
} else if lcpLen < searchLen {
|
|
search = search[lcpLen:]
|
|
c := currentNode.findChildWithLabel(search[0])
|
|
if c != nil {
|
|
// Go deeper
|
|
currentNode = c
|
|
continue
|
|
}
|
|
// Create child node
|
|
n := newNode(t, search, currentNode, nil, new(methodHandler), ppath, pnames, nil, nil)
|
|
n.addHandler(method, h)
|
|
switch t {
|
|
case staticKind:
|
|
currentNode.addStaticChild(n)
|
|
case paramKind:
|
|
currentNode.paramChild = n
|
|
case anyKind:
|
|
currentNode.anyChild = n
|
|
}
|
|
currentNode.isLeaf = currentNode.staticChildren == nil && currentNode.paramChild == nil && currentNode.anyChild == nil
|
|
} else {
|
|
// Node already exists
|
|
if h != nil {
|
|
currentNode.addHandler(method, h)
|
|
currentNode.ppath = ppath
|
|
if len(currentNode.pnames) == 0 { // Issue #729
|
|
currentNode.pnames = pnames
|
|
}
|
|
}
|
|
}
|
|
return
|
|
}
|
|
}
|
|
|
|
func newNode(t kind, pre string, p *node, sc children, mh *methodHandler, ppath string, pnames []string, paramChildren, anyChildren *node) *node {
|
|
return &node{
|
|
kind: t,
|
|
label: pre[0],
|
|
prefix: pre,
|
|
parent: p,
|
|
staticChildren: sc,
|
|
ppath: ppath,
|
|
pnames: pnames,
|
|
methodHandler: mh,
|
|
paramChild: paramChildren,
|
|
anyChild: anyChildren,
|
|
isLeaf: sc == nil && paramChildren == nil && anyChildren == nil,
|
|
isHandler: mh.isHandler(),
|
|
}
|
|
}
|
|
|
|
func (n *node) addStaticChild(c *node) {
|
|
n.staticChildren = append(n.staticChildren, c)
|
|
}
|
|
|
|
func (n *node) findStaticChild(l byte) *node {
|
|
for _, c := range n.staticChildren {
|
|
if c.label == l {
|
|
return c
|
|
}
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func (n *node) findChildWithLabel(l byte) *node {
|
|
for _, c := range n.staticChildren {
|
|
if c.label == l {
|
|
return c
|
|
}
|
|
}
|
|
if l == paramLabel {
|
|
return n.paramChild
|
|
}
|
|
if l == anyLabel {
|
|
return n.anyChild
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func (n *node) addHandler(method string, h HandlerFunc) {
|
|
switch method {
|
|
case http.MethodConnect:
|
|
n.methodHandler.connect = h
|
|
case http.MethodDelete:
|
|
n.methodHandler.delete = h
|
|
case http.MethodGet:
|
|
n.methodHandler.get = h
|
|
case http.MethodHead:
|
|
n.methodHandler.head = h
|
|
case http.MethodOptions:
|
|
n.methodHandler.options = h
|
|
case http.MethodPatch:
|
|
n.methodHandler.patch = h
|
|
case http.MethodPost:
|
|
n.methodHandler.post = h
|
|
case PROPFIND:
|
|
n.methodHandler.propfind = h
|
|
case http.MethodPut:
|
|
n.methodHandler.put = h
|
|
case http.MethodTrace:
|
|
n.methodHandler.trace = h
|
|
case REPORT:
|
|
n.methodHandler.report = h
|
|
}
|
|
|
|
if h != nil {
|
|
n.isHandler = true
|
|
} else {
|
|
n.isHandler = n.methodHandler.isHandler()
|
|
}
|
|
}
|
|
|
|
func (n *node) findHandler(method string) HandlerFunc {
|
|
switch method {
|
|
case http.MethodConnect:
|
|
return n.methodHandler.connect
|
|
case http.MethodDelete:
|
|
return n.methodHandler.delete
|
|
case http.MethodGet:
|
|
return n.methodHandler.get
|
|
case http.MethodHead:
|
|
return n.methodHandler.head
|
|
case http.MethodOptions:
|
|
return n.methodHandler.options
|
|
case http.MethodPatch:
|
|
return n.methodHandler.patch
|
|
case http.MethodPost:
|
|
return n.methodHandler.post
|
|
case PROPFIND:
|
|
return n.methodHandler.propfind
|
|
case http.MethodPut:
|
|
return n.methodHandler.put
|
|
case http.MethodTrace:
|
|
return n.methodHandler.trace
|
|
case REPORT:
|
|
return n.methodHandler.report
|
|
default:
|
|
return nil
|
|
}
|
|
}
|
|
|
|
func (n *node) checkMethodNotAllowed() HandlerFunc {
|
|
for _, m := range methods {
|
|
if h := n.findHandler(m); h != nil {
|
|
return MethodNotAllowedHandler
|
|
}
|
|
}
|
|
return NotFoundHandler
|
|
}
|
|
|
|
// Find lookup a handler registered for method and path. It also parses URL for path
|
|
// parameters and load them into context.
|
|
//
|
|
// For performance:
|
|
//
|
|
// - Get context from `Echo#AcquireContext()`
|
|
// - Reset it `Context#Reset()`
|
|
// - Return it `Echo#ReleaseContext()`.
|
|
func (r *Router) Find(method, path string, c Context) {
|
|
ctx := c.(*context)
|
|
ctx.path = path
|
|
currentNode := r.tree // Current node as root
|
|
|
|
var (
|
|
previousBestMatchNode *node
|
|
matchedHandler HandlerFunc
|
|
// search stores the remaining path to check for match. By each iteration we move from start of path to end of the path
|
|
// and search value gets shorter and shorter.
|
|
search = path
|
|
searchIndex = 0
|
|
paramIndex int // Param counter
|
|
paramValues = ctx.pvalues // Use the internal slice so the interface can keep the illusion of a dynamic slice
|
|
)
|
|
|
|
// Backtracking is needed when a dead end (leaf node) is reached in the router tree.
|
|
// To backtrack the current node will be changed to the parent node and the next kind for the
|
|
// router logic will be returned based on fromKind or kind of the dead end node (static > param > any).
|
|
// For example if there is no static node match we should check parent next sibling by kind (param).
|
|
// Backtracking itself does not check if there is a next sibling, this is done by the router logic.
|
|
backtrackToNextNodeKind := func(fromKind kind) (nextNodeKind kind, valid bool) {
|
|
previous := currentNode
|
|
currentNode = previous.parent
|
|
valid = currentNode != nil
|
|
|
|
// Next node type by priority
|
|
if previous.kind == anyKind {
|
|
nextNodeKind = staticKind
|
|
} else {
|
|
nextNodeKind = previous.kind + 1
|
|
}
|
|
|
|
if fromKind == staticKind {
|
|
// when backtracking is done from static kind block we did not change search so nothing to restore
|
|
return
|
|
}
|
|
|
|
// restore search to value it was before we move to current node we are backtracking from.
|
|
if previous.kind == staticKind {
|
|
searchIndex -= len(previous.prefix)
|
|
} else {
|
|
paramIndex--
|
|
// for param/any node.prefix value is always `:` so we can not deduce searchIndex from that and must use pValue
|
|
// for that index as it would also contain part of path we cut off before moving into node we are backtracking from
|
|
searchIndex -= len(paramValues[paramIndex])
|
|
paramValues[paramIndex] = ""
|
|
}
|
|
search = path[searchIndex:]
|
|
return
|
|
}
|
|
|
|
// Router tree is implemented by longest common prefix array (LCP array) https://en.wikipedia.org/wiki/LCP_array
|
|
// Tree search is implemented as for loop where one loop iteration is divided into 3 separate blocks
|
|
// Each of these blocks checks specific kind of node (static/param/any). Order of blocks reflex their priority in routing.
|
|
// Search order/priority is: static > param > any.
|
|
//
|
|
// Note: backtracking in tree is implemented by replacing/switching currentNode to previous node
|
|
// and hoping to (goto statement) next block by priority to check if it is the match.
|
|
for {
|
|
prefixLen := 0 // Prefix length
|
|
lcpLen := 0 // LCP (longest common prefix) length
|
|
|
|
if currentNode.kind == staticKind {
|
|
searchLen := len(search)
|
|
prefixLen = len(currentNode.prefix)
|
|
|
|
// LCP - Longest Common Prefix (https://en.wikipedia.org/wiki/LCP_array)
|
|
max := prefixLen
|
|
if searchLen < max {
|
|
max = searchLen
|
|
}
|
|
for ; lcpLen < max && search[lcpLen] == currentNode.prefix[lcpLen]; lcpLen++ {
|
|
}
|
|
}
|
|
|
|
if lcpLen != prefixLen {
|
|
// No matching prefix, let's backtrack to the first possible alternative node of the decision path
|
|
nk, ok := backtrackToNextNodeKind(staticKind)
|
|
if !ok {
|
|
return // No other possibilities on the decision path
|
|
} else if nk == paramKind {
|
|
goto Param
|
|
// NOTE: this case (backtracking from static node to previous any node) can not happen by current any matching logic. Any node is end of search currently
|
|
//} else if nk == anyKind {
|
|
// goto Any
|
|
} else {
|
|
// Not found (this should never be possible for static node we are looking currently)
|
|
break
|
|
}
|
|
}
|
|
|
|
// The full prefix has matched, remove the prefix from the remaining search
|
|
search = search[lcpLen:]
|
|
searchIndex = searchIndex + lcpLen
|
|
|
|
// Finish routing if no remaining search and we are on a node with handler and matching method type
|
|
if search == "" && currentNode.isHandler {
|
|
// check if current node has handler registered for http method we are looking for. we store currentNode as
|
|
// best matching in case we do no find no more routes matching this path+method
|
|
if previousBestMatchNode == nil {
|
|
previousBestMatchNode = currentNode
|
|
}
|
|
if h := currentNode.findHandler(method); h != nil {
|
|
matchedHandler = h
|
|
break
|
|
}
|
|
}
|
|
|
|
// Static node
|
|
if search != "" {
|
|
if child := currentNode.findStaticChild(search[0]); child != nil {
|
|
currentNode = child
|
|
continue
|
|
}
|
|
}
|
|
|
|
Param:
|
|
// Param node
|
|
if child := currentNode.paramChild; search != "" && child != nil {
|
|
currentNode = child
|
|
i := 0
|
|
l := len(search)
|
|
if currentNode.isLeaf {
|
|
// when param node does not have any children then param node should act similarly to any node - consider all remaining search as match
|
|
i = l
|
|
} else {
|
|
for ; i < l && search[i] != '/'; i++ {
|
|
}
|
|
}
|
|
|
|
paramValues[paramIndex] = search[:i]
|
|
paramIndex++
|
|
search = search[i:]
|
|
searchIndex = searchIndex + i
|
|
continue
|
|
}
|
|
|
|
Any:
|
|
// Any node
|
|
if child := currentNode.anyChild; child != nil {
|
|
// If any node is found, use remaining path for paramValues
|
|
currentNode = child
|
|
paramValues[len(currentNode.pnames)-1] = search
|
|
// update indexes/search in case we need to backtrack when no handler match is found
|
|
paramIndex++
|
|
searchIndex += +len(search)
|
|
search = ""
|
|
|
|
// check if current node has handler registered for http method we are looking for. we store currentNode as
|
|
// best matching in case we do no find no more routes matching this path+method
|
|
if previousBestMatchNode == nil {
|
|
previousBestMatchNode = currentNode
|
|
}
|
|
if h := currentNode.findHandler(method); h != nil {
|
|
matchedHandler = h
|
|
break
|
|
}
|
|
}
|
|
|
|
// Let's backtrack to the first possible alternative node of the decision path
|
|
nk, ok := backtrackToNextNodeKind(anyKind)
|
|
if !ok {
|
|
break // No other possibilities on the decision path
|
|
} else if nk == paramKind {
|
|
goto Param
|
|
} else if nk == anyKind {
|
|
goto Any
|
|
} else {
|
|
// Not found
|
|
break
|
|
}
|
|
}
|
|
|
|
if currentNode == nil && previousBestMatchNode == nil {
|
|
return // nothing matched at all
|
|
}
|
|
|
|
if matchedHandler != nil {
|
|
ctx.handler = matchedHandler
|
|
} else {
|
|
// use previous match as basis. although we have no matching handler we have path match.
|
|
// so we can send http.StatusMethodNotAllowed (405) instead of http.StatusNotFound (404)
|
|
currentNode = previousBestMatchNode
|
|
ctx.handler = currentNode.checkMethodNotAllowed()
|
|
}
|
|
ctx.path = currentNode.ppath
|
|
ctx.pnames = currentNode.pnames
|
|
|
|
return
|
|
}
|