685 lines
17 KiB
Go
685 lines
17 KiB
Go
// Copyright 2013 Julien Schmidt. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style license that can be found
|
|
// at https://github.com/julienschmidt/httprouter/blob/master/LICENSE
|
|
|
|
package gin
|
|
|
|
import (
|
|
"net/url"
|
|
"strings"
|
|
"unicode"
|
|
)
|
|
|
|
// Param is a single URL parameter, consisting of a key and a value.
|
|
type Param struct {
|
|
Key string
|
|
Value string
|
|
}
|
|
|
|
// Params is a Param-slice, as returned by the router.
|
|
// The slice is ordered, the first URL parameter is also the first slice value.
|
|
// It is therefore safe to read values by the index.
|
|
type Params []Param
|
|
|
|
// Get returns the value of the first Param which key matches the given name.
|
|
// If no matching Param is found, an empty string is returned.
|
|
func (ps Params) Get(name string) (string, bool) {
|
|
for _, entry := range ps {
|
|
if entry.Key == name {
|
|
return entry.Value, true
|
|
}
|
|
}
|
|
return "", false
|
|
}
|
|
|
|
// ByName returns the value of the first Param which key matches the given name.
|
|
// If no matching Param is found, an empty string is returned.
|
|
func (ps Params) ByName(name string) (va string) {
|
|
va, _ = ps.Get(name)
|
|
return
|
|
}
|
|
|
|
type methodTree struct {
|
|
method string
|
|
root *node
|
|
}
|
|
|
|
type methodTrees []methodTree
|
|
|
|
func (trees methodTrees) get(method string) *node {
|
|
for _, tree := range trees {
|
|
if tree.method == method {
|
|
return tree.root
|
|
}
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func min(a, b int) int {
|
|
if a <= b {
|
|
return a
|
|
}
|
|
return b
|
|
}
|
|
|
|
func longestCommonPrefix(a, b string) int {
|
|
i := 0
|
|
max := min(len(a), len(b))
|
|
for i < max && a[i] == b[i] {
|
|
i++
|
|
}
|
|
return i
|
|
}
|
|
|
|
func countParams(path string) uint8 {
|
|
var n uint
|
|
for i := 0; i < len(path); i++ {
|
|
if path[i] == ':' || path[i] == '*' {
|
|
n++
|
|
}
|
|
}
|
|
if n >= 255 {
|
|
return 255
|
|
}
|
|
return uint8(n)
|
|
}
|
|
|
|
type nodeType uint8
|
|
|
|
const (
|
|
static nodeType = iota // default
|
|
root
|
|
param
|
|
catchAll
|
|
)
|
|
|
|
type node struct {
|
|
path string
|
|
indices string
|
|
children []*node
|
|
handlers HandlersChain
|
|
priority uint32
|
|
nType nodeType
|
|
maxParams uint8
|
|
wildChild bool
|
|
fullPath string
|
|
}
|
|
|
|
// increments priority of the given child and reorders if necessary.
|
|
func (n *node) incrementChildPrio(pos int) int {
|
|
cs := n.children
|
|
cs[pos].priority++
|
|
prio := cs[pos].priority
|
|
|
|
// Adjust position (move to front)
|
|
newPos := pos
|
|
for ; newPos > 0 && cs[newPos-1].priority < prio; newPos-- {
|
|
// Swap node positions
|
|
cs[newPos-1], cs[newPos] = cs[newPos], cs[newPos-1]
|
|
}
|
|
|
|
// build new index char string
|
|
if newPos != pos {
|
|
n.indices = n.indices[:newPos] + // unchanged prefix, might be empty
|
|
n.indices[pos:pos+1] + // the index char we move
|
|
n.indices[newPos:pos] + n.indices[pos+1:] // rest without char at 'pos'
|
|
}
|
|
|
|
return newPos
|
|
}
|
|
|
|
// addRoute adds a node with the given handle to the path.
|
|
// Not concurrency-safe!
|
|
func (n *node) addRoute(path string, handlers HandlersChain) {
|
|
fullPath := path
|
|
n.priority++
|
|
numParams := countParams(path)
|
|
|
|
// Empty tree
|
|
if len(n.path) == 0 && len(n.children) == 0 {
|
|
n.insertChild(numParams, path, fullPath, handlers)
|
|
n.nType = root
|
|
return
|
|
}
|
|
|
|
parentFullPathIndex := 0
|
|
|
|
walk:
|
|
for {
|
|
// Update maxParams of the current node
|
|
if numParams > n.maxParams {
|
|
n.maxParams = numParams
|
|
}
|
|
|
|
// Find the longest common prefix.
|
|
// This also implies that the common prefix contains no ':' or '*'
|
|
// since the existing key can't contain those chars.
|
|
i := longestCommonPrefix(path, n.path)
|
|
|
|
// Split edge
|
|
if i < len(n.path) {
|
|
child := node{
|
|
path: n.path[i:],
|
|
wildChild: n.wildChild,
|
|
indices: n.indices,
|
|
children: n.children,
|
|
handlers: n.handlers,
|
|
priority: n.priority - 1,
|
|
fullPath: n.fullPath,
|
|
}
|
|
|
|
// Update maxParams (max of all children)
|
|
for _, v := range child.children {
|
|
if v.maxParams > child.maxParams {
|
|
child.maxParams = v.maxParams
|
|
}
|
|
}
|
|
|
|
n.children = []*node{&child}
|
|
// []byte for proper unicode char conversion, see #65
|
|
n.indices = string([]byte{n.path[i]})
|
|
n.path = path[:i]
|
|
n.handlers = nil
|
|
n.wildChild = false
|
|
n.fullPath = fullPath[:parentFullPathIndex+i]
|
|
}
|
|
|
|
// Make new node a child of this node
|
|
if i < len(path) {
|
|
path = path[i:]
|
|
|
|
if n.wildChild {
|
|
parentFullPathIndex += len(n.path)
|
|
n = n.children[0]
|
|
n.priority++
|
|
|
|
// Update maxParams of the child node
|
|
if numParams > n.maxParams {
|
|
n.maxParams = numParams
|
|
}
|
|
numParams--
|
|
|
|
// Check if the wildcard matches
|
|
if len(path) >= len(n.path) && n.path == path[:len(n.path)] {
|
|
// check for longer wildcard, e.g. :name and :names
|
|
if len(n.path) >= len(path) || path[len(n.path)] == '/' {
|
|
continue walk
|
|
}
|
|
}
|
|
|
|
pathSeg := path
|
|
if n.nType != catchAll {
|
|
pathSeg = strings.SplitN(path, "/", 2)[0]
|
|
}
|
|
prefix := fullPath[:strings.Index(fullPath, pathSeg)] + n.path
|
|
panic("'" + pathSeg +
|
|
"' in new path '" + fullPath +
|
|
"' conflicts with existing wildcard '" + n.path +
|
|
"' in existing prefix '" + prefix +
|
|
"'")
|
|
}
|
|
|
|
c := path[0]
|
|
|
|
// slash after param
|
|
if n.nType == param && c == '/' && len(n.children) == 1 {
|
|
parentFullPathIndex += len(n.path)
|
|
n = n.children[0]
|
|
n.priority++
|
|
continue walk
|
|
}
|
|
|
|
// Check if a child with the next path byte exists
|
|
for i, max := 0, len(n.indices); i < max; i++ {
|
|
if c == n.indices[i] {
|
|
parentFullPathIndex += len(n.path)
|
|
i = n.incrementChildPrio(i)
|
|
n = n.children[i]
|
|
continue walk
|
|
}
|
|
}
|
|
|
|
// Otherwise insert it
|
|
if c != ':' && c != '*' {
|
|
// []byte for proper unicode char conversion, see #65
|
|
n.indices += string([]byte{c})
|
|
child := &node{
|
|
maxParams: numParams,
|
|
fullPath: fullPath,
|
|
}
|
|
n.children = append(n.children, child)
|
|
n.incrementChildPrio(len(n.indices) - 1)
|
|
n = child
|
|
}
|
|
n.insertChild(numParams, path, fullPath, handlers)
|
|
return
|
|
}
|
|
|
|
// Otherwise and handle to current node
|
|
if n.handlers != nil {
|
|
panic("handlers are already registered for path '" + fullPath + "'")
|
|
}
|
|
n.handlers = handlers
|
|
return
|
|
}
|
|
}
|
|
|
|
// Search for a wildcard segment and check the name for invalid characters.
|
|
// Returns -1 as index, if no wildcard war found.
|
|
func findWildcard(path string) (wildcard string, i int, valid bool) {
|
|
// Find start
|
|
for start, c := range []byte(path) {
|
|
// A wildcard starts with ':' (param) or '*' (catch-all)
|
|
if c != ':' && c != '*' {
|
|
continue
|
|
}
|
|
|
|
// Find end and check for invalid characters
|
|
valid = true
|
|
for end, c := range []byte(path[start+1:]) {
|
|
switch c {
|
|
case '/':
|
|
return path[start : start+1+end], start, valid
|
|
case ':', '*':
|
|
valid = false
|
|
}
|
|
}
|
|
return path[start:], start, valid
|
|
}
|
|
return "", -1, false
|
|
}
|
|
|
|
func (n *node) insertChild(numParams uint8, path string, fullPath string, handlers HandlersChain) {
|
|
for numParams > 0 {
|
|
// Find prefix until first wildcard
|
|
wildcard, i, valid := findWildcard(path)
|
|
if i < 0 { // No wildcard found
|
|
break
|
|
}
|
|
|
|
// The wildcard name must not contain ':' and '*'
|
|
if !valid {
|
|
panic("only one wildcard per path segment is allowed, has: '" +
|
|
wildcard + "' in path '" + fullPath + "'")
|
|
}
|
|
|
|
// check if the wildcard has a name
|
|
if len(wildcard) < 2 {
|
|
panic("wildcards must be named with a non-empty name in path '" + fullPath + "'")
|
|
}
|
|
|
|
// Check if this node has existing children which would be
|
|
// unreachable if we insert the wildcard here
|
|
if len(n.children) > 0 {
|
|
panic("wildcard segment '" + wildcard +
|
|
"' conflicts with existing children in path '" + fullPath + "'")
|
|
}
|
|
|
|
if wildcard[0] == ':' { // param
|
|
if i > 0 {
|
|
// Insert prefix before the current wildcard
|
|
n.path = path[:i]
|
|
path = path[i:]
|
|
}
|
|
|
|
n.wildChild = true
|
|
child := &node{
|
|
nType: param,
|
|
path: wildcard,
|
|
maxParams: numParams,
|
|
fullPath: fullPath,
|
|
}
|
|
n.children = []*node{child}
|
|
n = child
|
|
n.priority++
|
|
numParams--
|
|
|
|
// if the path doesn't end with the wildcard, then there
|
|
// will be another non-wildcard subpath starting with '/'
|
|
if len(wildcard) < len(path) {
|
|
path = path[len(wildcard):]
|
|
|
|
child := &node{
|
|
maxParams: numParams,
|
|
priority: 1,
|
|
fullPath: fullPath,
|
|
}
|
|
n.children = []*node{child}
|
|
n = child
|
|
continue
|
|
}
|
|
|
|
// Otherwise we're done. Insert the handle in the new leaf
|
|
n.handlers = handlers
|
|
return
|
|
}
|
|
|
|
// catchAll
|
|
if i+len(wildcard) != len(path) || numParams > 1 {
|
|
panic("catch-all routes are only allowed at the end of the path in path '" + fullPath + "'")
|
|
}
|
|
|
|
if len(n.path) > 0 && n.path[len(n.path)-1] == '/' {
|
|
panic("catch-all conflicts with existing handle for the path segment root in path '" + fullPath + "'")
|
|
}
|
|
|
|
// currently fixed width 1 for '/'
|
|
i--
|
|
if path[i] != '/' {
|
|
panic("no / before catch-all in path '" + fullPath + "'")
|
|
}
|
|
|
|
n.path = path[:i]
|
|
|
|
// First node: catchAll node with empty path
|
|
child := &node{
|
|
wildChild: true,
|
|
nType: catchAll,
|
|
maxParams: 1,
|
|
fullPath: fullPath,
|
|
}
|
|
// update maxParams of the parent node
|
|
if n.maxParams < 1 {
|
|
n.maxParams = 1
|
|
}
|
|
n.children = []*node{child}
|
|
n.indices = string('/')
|
|
n = child
|
|
n.priority++
|
|
|
|
// second node: node holding the variable
|
|
child = &node{
|
|
path: path[i:],
|
|
nType: catchAll,
|
|
maxParams: 1,
|
|
handlers: handlers,
|
|
priority: 1,
|
|
fullPath: fullPath,
|
|
}
|
|
n.children = []*node{child}
|
|
|
|
return
|
|
}
|
|
|
|
// If no wildcard was found, simply insert the path and handle
|
|
n.path = path
|
|
n.handlers = handlers
|
|
n.fullPath = fullPath
|
|
}
|
|
|
|
// nodeValue holds return values of (*Node).getValue method
|
|
type nodeValue struct {
|
|
handlers HandlersChain
|
|
params Params
|
|
tsr bool
|
|
fullPath string
|
|
}
|
|
|
|
// getValue returns the handle registered with the given path (key). The values of
|
|
// wildcards are saved to a map.
|
|
// If no handle can be found, a TSR (trailing slash redirect) recommendation is
|
|
// made if a handle exists with an extra (without the) trailing slash for the
|
|
// given path.
|
|
func (n *node) getValue(path string, po Params, unescape bool) (value nodeValue) {
|
|
value.params = po
|
|
walk: // Outer loop for walking the tree
|
|
for {
|
|
prefix := n.path
|
|
if path == prefix {
|
|
// We should have reached the node containing the handle.
|
|
// Check if this node has a handle registered.
|
|
if value.handlers = n.handlers; value.handlers != nil {
|
|
value.fullPath = n.fullPath
|
|
return
|
|
}
|
|
|
|
if path == "/" && n.wildChild && n.nType != root {
|
|
value.tsr = true
|
|
return
|
|
}
|
|
|
|
// No handle found. Check if a handle for this path + a
|
|
// trailing slash exists for trailing slash recommendation
|
|
indices := n.indices
|
|
for i, max := 0, len(indices); i < max; i++ {
|
|
if indices[i] == '/' {
|
|
n = n.children[i]
|
|
value.tsr = (len(n.path) == 1 && n.handlers != nil) ||
|
|
(n.nType == catchAll && n.children[0].handlers != nil)
|
|
return
|
|
}
|
|
}
|
|
|
|
return
|
|
}
|
|
|
|
if len(path) > len(prefix) && path[:len(prefix)] == prefix {
|
|
path = path[len(prefix):]
|
|
// If this node does not have a wildcard (param or catchAll)
|
|
// child, we can just look up the next child node and continue
|
|
// to walk down the tree
|
|
if !n.wildChild {
|
|
c := path[0]
|
|
indices := n.indices
|
|
for i, max := 0, len(indices); i < max; i++ {
|
|
if c == indices[i] {
|
|
n = n.children[i]
|
|
continue walk
|
|
}
|
|
}
|
|
|
|
// Nothing found.
|
|
// We can recommend to redirect to the same URL without a
|
|
// trailing slash if a leaf exists for that path.
|
|
value.tsr = path == "/" && n.handlers != nil
|
|
return
|
|
}
|
|
|
|
// handle wildcard child
|
|
n = n.children[0]
|
|
switch n.nType {
|
|
case param:
|
|
// find param end (either '/' or path end)
|
|
end := 0
|
|
for end < len(path) && path[end] != '/' {
|
|
end++
|
|
}
|
|
|
|
// save param value
|
|
if cap(value.params) < int(n.maxParams) {
|
|
value.params = make(Params, 0, n.maxParams)
|
|
}
|
|
i := len(value.params)
|
|
value.params = value.params[:i+1] // expand slice within preallocated capacity
|
|
value.params[i].Key = n.path[1:]
|
|
val := path[:end]
|
|
if unescape {
|
|
var err error
|
|
if value.params[i].Value, err = url.QueryUnescape(val); err != nil {
|
|
value.params[i].Value = val // fallback, in case of error
|
|
}
|
|
} else {
|
|
value.params[i].Value = val
|
|
}
|
|
|
|
// we need to go deeper!
|
|
if end < len(path) {
|
|
if len(n.children) > 0 {
|
|
path = path[end:]
|
|
n = n.children[0]
|
|
continue walk
|
|
}
|
|
|
|
// ... but we can't
|
|
value.tsr = len(path) == end+1
|
|
return
|
|
}
|
|
|
|
if value.handlers = n.handlers; value.handlers != nil {
|
|
value.fullPath = n.fullPath
|
|
return
|
|
}
|
|
if len(n.children) == 1 {
|
|
// No handle found. Check if a handle for this path + a
|
|
// trailing slash exists for TSR recommendation
|
|
n = n.children[0]
|
|
value.tsr = n.path == "/" && n.handlers != nil
|
|
}
|
|
return
|
|
|
|
case catchAll:
|
|
// save param value
|
|
if cap(value.params) < int(n.maxParams) {
|
|
value.params = make(Params, 0, n.maxParams)
|
|
}
|
|
i := len(value.params)
|
|
value.params = value.params[:i+1] // expand slice within preallocated capacity
|
|
value.params[i].Key = n.path[2:]
|
|
if unescape {
|
|
var err error
|
|
if value.params[i].Value, err = url.QueryUnescape(path); err != nil {
|
|
value.params[i].Value = path // fallback, in case of error
|
|
}
|
|
} else {
|
|
value.params[i].Value = path
|
|
}
|
|
|
|
value.handlers = n.handlers
|
|
value.fullPath = n.fullPath
|
|
return
|
|
|
|
default:
|
|
panic("invalid node type")
|
|
}
|
|
}
|
|
|
|
// Nothing found. We can recommend to redirect to the same URL with an
|
|
// extra trailing slash if a leaf exists for that path
|
|
value.tsr = (path == "/") ||
|
|
(len(prefix) == len(path)+1 && prefix[len(path)] == '/' &&
|
|
path == prefix[:len(prefix)-1] && n.handlers != nil)
|
|
return
|
|
}
|
|
}
|
|
|
|
// findCaseInsensitivePath makes a case-insensitive lookup of the given path and tries to find a handler.
|
|
// It can optionally also fix trailing slashes.
|
|
// It returns the case-corrected path and a bool indicating whether the lookup
|
|
// was successful.
|
|
func (n *node) findCaseInsensitivePath(path string, fixTrailingSlash bool) (ciPath []byte, found bool) {
|
|
ciPath = make([]byte, 0, len(path)+1) // preallocate enough memory
|
|
|
|
// Outer loop for walking the tree
|
|
for len(path) >= len(n.path) && strings.EqualFold(path[:len(n.path)], n.path) {
|
|
path = path[len(n.path):]
|
|
ciPath = append(ciPath, n.path...)
|
|
|
|
if len(path) == 0 {
|
|
// We should have reached the node containing the handle.
|
|
// Check if this node has a handle registered.
|
|
if n.handlers != nil {
|
|
return ciPath, true
|
|
}
|
|
|
|
// No handle found.
|
|
// Try to fix the path by adding a trailing slash
|
|
if fixTrailingSlash {
|
|
for i := 0; i < len(n.indices); i++ {
|
|
if n.indices[i] == '/' {
|
|
n = n.children[i]
|
|
if (len(n.path) == 1 && n.handlers != nil) ||
|
|
(n.nType == catchAll && n.children[0].handlers != nil) {
|
|
return append(ciPath, '/'), true
|
|
}
|
|
return
|
|
}
|
|
}
|
|
}
|
|
return
|
|
}
|
|
|
|
// If this node does not have a wildcard (param or catchAll) child,
|
|
// we can just look up the next child node and continue to walk down
|
|
// the tree
|
|
if !n.wildChild {
|
|
r := unicode.ToLower(rune(path[0]))
|
|
for i, index := range n.indices {
|
|
// must use recursive approach since both index and
|
|
// ToLower(index) could exist. We must check both.
|
|
if r == unicode.ToLower(index) {
|
|
out, found := n.children[i].findCaseInsensitivePath(path, fixTrailingSlash)
|
|
if found {
|
|
return append(ciPath, out...), true
|
|
}
|
|
}
|
|
}
|
|
|
|
// Nothing found. We can recommend to redirect to the same URL
|
|
// without a trailing slash if a leaf exists for that path
|
|
found = fixTrailingSlash && path == "/" && n.handlers != nil
|
|
return
|
|
}
|
|
|
|
n = n.children[0]
|
|
switch n.nType {
|
|
case param:
|
|
// Find param end (either '/' or path end)
|
|
end := 0
|
|
for end < len(path) && path[end] != '/' {
|
|
end++
|
|
}
|
|
|
|
// add param value to case insensitive path
|
|
ciPath = append(ciPath, path[:end]...)
|
|
|
|
// we need to go deeper!
|
|
if end < len(path) {
|
|
if len(n.children) > 0 {
|
|
path = path[end:]
|
|
n = n.children[0]
|
|
continue
|
|
}
|
|
|
|
// ... but we can't
|
|
if fixTrailingSlash && len(path) == end+1 {
|
|
return ciPath, true
|
|
}
|
|
return
|
|
}
|
|
|
|
if n.handlers != nil {
|
|
return ciPath, true
|
|
}
|
|
if fixTrailingSlash && len(n.children) == 1 {
|
|
// No handle found. Check if a handle for this path + a
|
|
// trailing slash exists
|
|
n = n.children[0]
|
|
if n.path == "/" && n.handlers != nil {
|
|
return append(ciPath, '/'), true
|
|
}
|
|
}
|
|
return
|
|
|
|
case catchAll:
|
|
return append(ciPath, path...), true
|
|
|
|
default:
|
|
panic("invalid node type")
|
|
}
|
|
}
|
|
|
|
// Nothing found.
|
|
// Try to fix the path by adding / removing a trailing slash
|
|
if fixTrailingSlash {
|
|
if path == "/" {
|
|
return ciPath, true
|
|
}
|
|
if len(path)+1 == len(n.path) && n.path[len(path)] == '/' &&
|
|
strings.EqualFold(path, n.path[:len(path)]) &&
|
|
n.handlers != nil {
|
|
return append(ciPath, n.path...), true
|
|
}
|
|
}
|
|
return
|
|
}
|