Add ability to capture variables in query strings

mux_test.go

@@ -471,6 +471,24 @@ func TestQueries(t *testing.T) {
 			path:        "",
 			shouldMatch: false,
 		},
+		{
+			title:       "Queries route with pattern, match",
+			route:       new(Route).Queries("foo", "{v1}"),
+			request:     newRequest("GET", "http://localhost?foo=bar"),
+			vars:        map[string]string{"v1": "bar"},
+			host:        "",
+			path:        "",
+			shouldMatch: true,
+		},
+		{
+			title:       "Queries route with multiple patterns, match",
+			route:       new(Route).Queries("foo", "{v1}", "baz", "{v2}"),
+			request:     newRequest("GET", "http://localhost?foo=bar&baz=ding"),
+			vars:        map[string]string{"v1": "bar", "v2": "ding"},
+			host:        "",
+			path:        "",
+			shouldMatch: true,
+		},
 	}
 
 	for _, test := range tests {

old_test.go

@@ -735,7 +735,7 @@ func TestNewRegexp(t *testing.T) {
 	}
 
 	for pattern, paths := range tests {
-		p, _ = newRouteRegexp(pattern, false, false, false)
+		p, _ = newRouteRegexp(pattern, false, false, false, false)
 		for path, result := range paths {
 			matches = p.regexp.FindStringSubmatch(path)
 			if result == nil {

regexp.go

@@ -14,7 +14,7 @@ import (
 )
 
 // newRouteRegexp parses a route template and returns a routeRegexp,
-// used to match a host or path.
+// 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
@@ -23,7 +23,7 @@ import (
 // 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, matchHost, matchPrefix, strictSlash bool) (*routeRegexp, error) {
+func newRouteRegexp(tpl string, matchHost, matchPrefix, matchQuery, strictSlash bool) (*routeRegexp, error) {
 	// Check if it is well-formed.
 	idxs, errBraces := braceIndices(tpl)
 	if errBraces != nil {
@@ -33,7 +33,10 @@ func newRouteRegexp(tpl string, matchHost, matchPrefix, strictSlash bool) (*rout
 	template := tpl
 	// Now let's parse it.
 	defaultPattern := "[^/]+"
-	if matchHost {
+	if matchQuery {
+		defaultPattern = "[^?]+"
+		matchPrefix, strictSlash = true, false
+	} else if matchHost {
 		defaultPattern = "[^.]+"
 		matchPrefix, strictSlash = false, false
 	}
@@ -49,6 +52,9 @@ func newRouteRegexp(tpl string, matchHost, matchPrefix, strictSlash bool) (*rout
 	varsN := make([]string, len(idxs)/2)
 	varsR := make([]*regexp.Regexp, len(idxs)/2)
 	pattern := bytes.NewBufferString("^")
+	if matchQuery {
+		pattern = bytes.NewBufferString("")
+	}
 	reverse := bytes.NewBufferString("")
 	var end int
 	var err error
@@ -100,6 +106,7 @@ func newRouteRegexp(tpl string, matchHost, matchPrefix, strictSlash bool) (*rout
 	return &routeRegexp{
 		template:    template,
 		matchHost:   matchHost,
+		matchQuery:  matchQuery,
 		strictSlash: strictSlash,
 		regexp:      reg,
 		reverse:     reverse.String(),
@@ -113,8 +120,10 @@ func newRouteRegexp(tpl string, matchHost, matchPrefix, strictSlash bool) (*rout
 type routeRegexp struct {
 	// The unmodified template.
 	template string
-	// True for host match, false for path match.
+	// True for host match, false for path or query string match.
 	matchHost bool
+	// True for query string match, false for path and host match.
+	matchQuery bool
 	// The strictSlash value defined on the route, but disabled if PathPrefix was used.
 	strictSlash bool
 	// Expanded regexp.
@@ -130,7 +139,11 @@ type routeRegexp struct {
 // Match matches the regexp against the URL host or path.
 func (r *routeRegexp) Match(req *http.Request, match *RouteMatch) bool {
 	if !r.matchHost {
-		return r.regexp.MatchString(req.URL.Path)
+		if r.matchQuery {
+			return r.regexp.MatchString(req.URL.RawQuery)
+		} else {
+			return r.regexp.MatchString(req.URL.Path)
+		}
 	}
 	return r.regexp.MatchString(getHost(req))
 }
@@ -196,8 +209,9 @@ func braceIndices(s string) ([]int, error) {
 
 // routeRegexpGroup groups the route matchers that carry variables.
 type routeRegexpGroup struct {
-	host *routeRegexp
+	host  *routeRegexp
-	path *routeRegexp
+	path  *routeRegexp
+	query *routeRegexp
 }
 
 // setMatch extracts the variables from the URL once a route matches.
@@ -234,6 +248,15 @@ func (v *routeRegexpGroup) setMatch(req *http.Request, m *RouteMatch, r *Route)
 			}
 		}
 	}
+	// Store query string variables.
+	if v.query != nil {
+		queryVars := v.query.regexp.FindStringSubmatch(req.URL.RawQuery)
+		if queryVars != nil {
+			for k, v := range v.query.varsN {
+				m.Vars[v] = queryVars[k+1]
+			}
+		}
+	}
 }
 
 // getHost tries its best to return the request host.

route.go

@@ -5,6 +5,7 @@
 package mux
 
 import (
+	"bytes"
 	"errors"
 	"fmt"
 	"net/http"
@@ -135,12 +136,12 @@ func (r *Route) addMatcher(m matcher) *Route {
 }
 
 // addRegexpMatcher adds a host or path matcher and builder to a route.
-func (r *Route) addRegexpMatcher(tpl string, matchHost, matchPrefix bool) error {
+func (r *Route) addRegexpMatcher(tpl string, matchHost, matchPrefix, matchQuery bool) error {
 	if r.err != nil {
 		return r.err
 	}
 	r.regexp = r.getRegexpGroup()
-	if !matchHost {
+	if !matchHost && !matchQuery {
 		if len(tpl) == 0 || tpl[0] != '/' {
 			return fmt.Errorf("mux: path must start with a slash, got %q", tpl)
 		}
@@ -148,7 +149,7 @@ func (r *Route) addRegexpMatcher(tpl string, matchHost, matchPrefix bool) error
 			tpl = strings.TrimRight(r.regexp.path.template, "/") + tpl
 		}
 	}
-	rr, err := newRouteRegexp(tpl, matchHost, matchPrefix, r.strictSlash)
+	rr, err := newRouteRegexp(tpl, matchHost, matchPrefix, matchQuery, r.strictSlash)
 	if err != nil {
 		return err
 	}
@@ -158,6 +159,11 @@ func (r *Route) addRegexpMatcher(tpl string, matchHost, matchPrefix bool) error
 				return err
 			}
 		}
+		if r.regexp.query != nil {
+			if err = uniqueVars(rr.varsN, r.regexp.query.varsN); err != nil {
+				return err
+			}
+		}
 		r.regexp.host = rr
 	} else {
 		if r.regexp.host != nil {
@@ -165,7 +171,21 @@ func (r *Route) addRegexpMatcher(tpl string, matchHost, matchPrefix bool) error
 				return err
 			}
 		}
-		r.regexp.path = rr
+		if matchQuery {
+			if r.regexp.path != nil {
+				if err = uniqueVars(rr.varsN, r.regexp.path.varsN); err != nil {
+					return err
+				}
+			}
+			r.regexp.query = rr
+		} else {
+			if r.regexp.query != nil {
+				if err = uniqueVars(rr.varsN, r.regexp.query.varsN); err != nil {
+					return err
+				}
+			}
+			r.regexp.path = rr
+		}
 	}
 	r.addMatcher(rr)
 	return nil
@@ -219,7 +239,7 @@ func (r *Route) Headers(pairs ...string) *Route {
 // Variable names must be unique in a given route. They can be retrieved
 // calling mux.Vars(request).
 func (r *Route) Host(tpl string) *Route {
-	r.err = r.addRegexpMatcher(tpl, true, false)
+	r.err = r.addRegexpMatcher(tpl, true, false, false)
 	return r
 }
 
@@ -278,7 +298,7 @@ func (r *Route) Methods(methods ...string) *Route {
 // Variable names must be unique in a given route. They can be retrieved
 // calling mux.Vars(request).
 func (r *Route) Path(tpl string) *Route {
-	r.err = r.addRegexpMatcher(tpl, false, false)
+	r.err = r.addRegexpMatcher(tpl, false, false, false)
 	return r
 }
 
@@ -294,35 +314,40 @@ func (r *Route) Path(tpl string) *Route {
 // Also note that the setting of Router.StrictSlash() has no effect on routes
 // with a PathPrefix matcher.
 func (r *Route) PathPrefix(tpl string) *Route {
-	r.err = r.addRegexpMatcher(tpl, false, true)
+	r.err = r.addRegexpMatcher(tpl, false, true, false)
 	return r
 }
 
 // Query ----------------------------------------------------------------------
 
-// queryMatcher matches the request against URL queries.
-type queryMatcher map[string]string
-
-func (m queryMatcher) Match(r *http.Request, match *RouteMatch) bool {
-	return matchMap(m, r.URL.Query(), false)
-}
-
 // Queries adds a matcher for URL query values.
-// It accepts a sequence of key/value pairs. For example:
+// It accepts a sequence of key/value pairs. Values may define variables.
+// For example:
 //
 //     r := mux.NewRouter()
-//     r.Queries("foo", "bar", "baz", "ding")
+//     r.Queries("foo", "bar", "id", "{id:[0-9]+}")
 //
 // The above route will only match if the URL contains the defined queries
-// values, e.g.: ?foo=bar&baz=ding.
+// values, e.g.: ?foo=bar&id=42.
 //
 // It the value is an empty string, it will match any value if the key is set.
+//
+// Variables can define an optional regexp pattern to me matched:
+//
+// - {name} matches anything until the next slash.
+//
+// - {name:pattern} matches the given regexp pattern.
+
 func (r *Route) Queries(pairs ...string) *Route {
-	if r.err == nil {
+	var buf bytes.Buffer
-		var queries map[string]string
+	var queries map[string]string
-		queries, r.err = mapFromPairs(pairs...)
+	buf.WriteString("")
-		return r.addMatcher(queryMatcher(queries))
+	queries, r.err = mapFromPairs(pairs...)
+	for k, v := range queries {
+		buf.WriteString(fmt.Sprintf("%s=%s&", k, v))
 	}
+	tpl := strings.TrimRight(buf.String(), "&")
+	r.err = r.addRegexpMatcher(tpl, false, true, true)
 	return r
 }
 
@@ -498,8 +523,9 @@ func (r *Route) getRegexpGroup() *routeRegexpGroup {
 		} else {
 			// Copy.
 			r.regexp = &routeRegexpGroup{
-				host: regexp.host,
+				host:  regexp.host,
-				path: regexp.path,
+				path:  regexp.path,
+				query: regexp.query,
 			}
 		}
 	}