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authorMichael Muré <batolettre@gmail.com>2018-07-16 23:20:23 +0200
committerMichael Muré <batolettre@gmail.com>2018-07-16 23:23:43 +0200
commit1d678dfdfa026968dbb19795c9bed16385603b21 (patch)
treecac862609d0103ee30da39cd0054b11884248e9d /vendor/github.com/gorilla/mux/regexp.go
parent131a862d313f12808d63e832126317a27226940b (diff)
downloadgit-bug-1d678dfdfa026968dbb19795c9bed16385603b21.tar.gz
vendor dependencies with dep
Diffstat (limited to 'vendor/github.com/gorilla/mux/regexp.go')
-rw-r--r--vendor/github.com/gorilla/mux/regexp.go332
1 files changed, 332 insertions, 0 deletions
diff --git a/vendor/github.com/gorilla/mux/regexp.go b/vendor/github.com/gorilla/mux/regexp.go
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--- /dev/null
+++ b/vendor/github.com/gorilla/mux/regexp.go
@@ -0,0 +1,332 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mux
+
+import (
+ "bytes"
+ "fmt"
+ "net/http"
+ "net/url"
+ "regexp"
+ "strconv"
+ "strings"
+)
+
+type routeRegexpOptions struct {
+ strictSlash bool
+ useEncodedPath bool
+}
+
+type regexpType int
+
+const (
+ regexpTypePath regexpType = 0
+ regexpTypeHost regexpType = 1
+ regexpTypePrefix regexpType = 2
+ regexpTypeQuery regexpType = 3
+)
+
+// newRouteRegexp parses a route template and returns a routeRegexp,
+// used to match a host, a path or a query string.
+//
+// It will extract named variables, assemble a regexp to be matched, create
+// a "reverse" template to build URLs and compile regexps to validate variable
+// values used in URL building.
+//
+// Previously we accepted only Python-like identifiers for variable
+// names ([a-zA-Z_][a-zA-Z0-9_]*), but currently the only restriction is that
+// name and pattern can't be empty, and names can't contain a colon.
+func newRouteRegexp(tpl string, typ regexpType, options routeRegexpOptions) (*routeRegexp, error) {
+ // Check if it is well-formed.
+ idxs, errBraces := braceIndices(tpl)
+ if errBraces != nil {
+ return nil, errBraces
+ }
+ // Backup the original.
+ template := tpl
+ // Now let's parse it.
+ defaultPattern := "[^/]+"
+ if typ == regexpTypeQuery {
+ defaultPattern = ".*"
+ } else if typ == regexpTypeHost {
+ defaultPattern = "[^.]+"
+ }
+ // Only match strict slash if not matching
+ if typ != regexpTypePath {
+ options.strictSlash = false
+ }
+ // Set a flag for strictSlash.
+ endSlash := false
+ if options.strictSlash && strings.HasSuffix(tpl, "/") {
+ tpl = tpl[:len(tpl)-1]
+ endSlash = true
+ }
+ varsN := make([]string, len(idxs)/2)
+ varsR := make([]*regexp.Regexp, len(idxs)/2)
+ pattern := bytes.NewBufferString("")
+ pattern.WriteByte('^')
+ reverse := bytes.NewBufferString("")
+ var end int
+ var err error
+ for i := 0; i < len(idxs); i += 2 {
+ // Set all values we are interested in.
+ raw := tpl[end:idxs[i]]
+ end = idxs[i+1]
+ parts := strings.SplitN(tpl[idxs[i]+1:end-1], ":", 2)
+ name := parts[0]
+ patt := defaultPattern
+ if len(parts) == 2 {
+ patt = parts[1]
+ }
+ // Name or pattern can't be empty.
+ if name == "" || patt == "" {
+ return nil, fmt.Errorf("mux: missing name or pattern in %q",
+ tpl[idxs[i]:end])
+ }
+ // Build the regexp pattern.
+ fmt.Fprintf(pattern, "%s(?P<%s>%s)", regexp.QuoteMeta(raw), varGroupName(i/2), patt)
+
+ // Build the reverse template.
+ fmt.Fprintf(reverse, "%s%%s", raw)
+
+ // Append variable name and compiled pattern.
+ varsN[i/2] = name
+ varsR[i/2], err = regexp.Compile(fmt.Sprintf("^%s$", patt))
+ if err != nil {
+ return nil, err
+ }
+ }
+ // Add the remaining.
+ raw := tpl[end:]
+ pattern.WriteString(regexp.QuoteMeta(raw))
+ if options.strictSlash {
+ pattern.WriteString("[/]?")
+ }
+ if typ == regexpTypeQuery {
+ // Add the default pattern if the query value is empty
+ if queryVal := strings.SplitN(template, "=", 2)[1]; queryVal == "" {
+ pattern.WriteString(defaultPattern)
+ }
+ }
+ if typ != regexpTypePrefix {
+ pattern.WriteByte('$')
+ }
+ reverse.WriteString(raw)
+ if endSlash {
+ reverse.WriteByte('/')
+ }
+ // Compile full regexp.
+ reg, errCompile := regexp.Compile(pattern.String())
+ if errCompile != nil {
+ return nil, errCompile
+ }
+
+ // Check for capturing groups which used to work in older versions
+ if reg.NumSubexp() != len(idxs)/2 {
+ panic(fmt.Sprintf("route %s contains capture groups in its regexp. ", template) +
+ "Only non-capturing groups are accepted: e.g. (?:pattern) instead of (pattern)")
+ }
+
+ // Done!
+ return &routeRegexp{
+ template: template,
+ regexpType: typ,
+ options: options,
+ regexp: reg,
+ reverse: reverse.String(),
+ varsN: varsN,
+ varsR: varsR,
+ }, nil
+}
+
+// routeRegexp stores a regexp to match a host or path and information to
+// collect and validate route variables.
+type routeRegexp struct {
+ // The unmodified template.
+ template string
+ // The type of match
+ regexpType regexpType
+ // Options for matching
+ options routeRegexpOptions
+ // Expanded regexp.
+ regexp *regexp.Regexp
+ // Reverse template.
+ reverse string
+ // Variable names.
+ varsN []string
+ // Variable regexps (validators).
+ varsR []*regexp.Regexp
+}
+
+// Match matches the regexp against the URL host or path.
+func (r *routeRegexp) Match(req *http.Request, match *RouteMatch) bool {
+ if r.regexpType != regexpTypeHost {
+ if r.regexpType == regexpTypeQuery {
+ return r.matchQueryString(req)
+ }
+ path := req.URL.Path
+ if r.options.useEncodedPath {
+ path = req.URL.EscapedPath()
+ }
+ return r.regexp.MatchString(path)
+ }
+
+ return r.regexp.MatchString(getHost(req))
+}
+
+// url builds a URL part using the given values.
+func (r *routeRegexp) url(values map[string]string) (string, error) {
+ urlValues := make([]interface{}, len(r.varsN))
+ for k, v := range r.varsN {
+ value, ok := values[v]
+ if !ok {
+ return "", fmt.Errorf("mux: missing route variable %q", v)
+ }
+ if r.regexpType == regexpTypeQuery {
+ value = url.QueryEscape(value)
+ }
+ urlValues[k] = value
+ }
+ rv := fmt.Sprintf(r.reverse, urlValues...)
+ if !r.regexp.MatchString(rv) {
+ // The URL is checked against the full regexp, instead of checking
+ // individual variables. This is faster but to provide a good error
+ // message, we check individual regexps if the URL doesn't match.
+ for k, v := range r.varsN {
+ if !r.varsR[k].MatchString(values[v]) {
+ return "", fmt.Errorf(
+ "mux: variable %q doesn't match, expected %q", values[v],
+ r.varsR[k].String())
+ }
+ }
+ }
+ return rv, nil
+}
+
+// getURLQuery returns a single query parameter from a request URL.
+// For a URL with foo=bar&baz=ding, we return only the relevant key
+// value pair for the routeRegexp.
+func (r *routeRegexp) getURLQuery(req *http.Request) string {
+ if r.regexpType != regexpTypeQuery {
+ return ""
+ }
+ templateKey := strings.SplitN(r.template, "=", 2)[0]
+ for key, vals := range req.URL.Query() {
+ if key == templateKey && len(vals) > 0 {
+ return key + "=" + vals[0]
+ }
+ }
+ return ""
+}
+
+func (r *routeRegexp) matchQueryString(req *http.Request) bool {
+ return r.regexp.MatchString(r.getURLQuery(req))
+}
+
+// braceIndices returns the first level curly brace indices from a string.
+// It returns an error in case of unbalanced braces.
+func braceIndices(s string) ([]int, error) {
+ var level, idx int
+ var idxs []int
+ for i := 0; i < len(s); i++ {
+ switch s[i] {
+ case '{':
+ if level++; level == 1 {
+ idx = i
+ }
+ case '}':
+ if level--; level == 0 {
+ idxs = append(idxs, idx, i+1)
+ } else if level < 0 {
+ return nil, fmt.Errorf("mux: unbalanced braces in %q", s)
+ }
+ }
+ }
+ if level != 0 {
+ return nil, fmt.Errorf("mux: unbalanced braces in %q", s)
+ }
+ return idxs, nil
+}
+
+// varGroupName builds a capturing group name for the indexed variable.
+func varGroupName(idx int) string {
+ return "v" + strconv.Itoa(idx)
+}
+
+// ----------------------------------------------------------------------------
+// routeRegexpGroup
+// ----------------------------------------------------------------------------
+
+// routeRegexpGroup groups the route matchers that carry variables.
+type routeRegexpGroup struct {
+ host *routeRegexp
+ path *routeRegexp
+ queries []*routeRegexp
+}
+
+// setMatch extracts the variables from the URL once a route matches.
+func (v *routeRegexpGroup) setMatch(req *http.Request, m *RouteMatch, r *Route) {
+ // Store host variables.
+ if v.host != nil {
+ host := getHost(req)
+ matches := v.host.regexp.FindStringSubmatchIndex(host)
+ if len(matches) > 0 {
+ extractVars(host, matches, v.host.varsN, m.Vars)
+ }
+ }
+ path := req.URL.Path
+ if r.useEncodedPath {
+ path = req.URL.EscapedPath()
+ }
+ // Store path variables.
+ if v.path != nil {
+ matches := v.path.regexp.FindStringSubmatchIndex(path)
+ if len(matches) > 0 {
+ extractVars(path, matches, v.path.varsN, m.Vars)
+ // Check if we should redirect.
+ if v.path.options.strictSlash {
+ p1 := strings.HasSuffix(path, "/")
+ p2 := strings.HasSuffix(v.path.template, "/")
+ if p1 != p2 {
+ u, _ := url.Parse(req.URL.String())
+ if p1 {
+ u.Path = u.Path[:len(u.Path)-1]
+ } else {
+ u.Path += "/"
+ }
+ m.Handler = http.RedirectHandler(u.String(), 301)
+ }
+ }
+ }
+ }
+ // Store query string variables.
+ for _, q := range v.queries {
+ queryURL := q.getURLQuery(req)
+ matches := q.regexp.FindStringSubmatchIndex(queryURL)
+ if len(matches) > 0 {
+ extractVars(queryURL, matches, q.varsN, m.Vars)
+ }
+ }
+}
+
+// getHost tries its best to return the request host.
+func getHost(r *http.Request) string {
+ if r.URL.IsAbs() {
+ return r.URL.Host
+ }
+ host := r.Host
+ // Slice off any port information.
+ if i := strings.Index(host, ":"); i != -1 {
+ host = host[:i]
+ }
+ return host
+
+}
+
+func extractVars(input string, matches []int, names []string, output map[string]string) {
+ for i, name := range names {
+ output[name] = input[matches[2*i+2]:matches[2*i+3]]
+ }
+}