Merge pull request #479 from abiosoft/rewrite-patch

rewrite: not_has, not_match, multiple to, and status codes

caddy/setup/rewrite.go

@@ -2,6 +2,7 @@ package setup
 
 import (
 	"net/http"
+	"strconv"
 	"strings"
 
 	"github.com/mholt/caddy/middleware"
@@ -33,6 +34,7 @@ func rewriteParse(c *Controller) ([]rewrite.Rule, error) {
 		var err error
 		var base = "/"
 		var pattern, to string
+		var status int
 		var ext []string
 
 		args := c.RemainingArgs()
@@ -40,9 +42,6 @@ func rewriteParse(c *Controller) ([]rewrite.Rule, error) {
 		var ifs []rewrite.If
 
 		switch len(args) {
-		case 2:
-			rule = rewrite.NewSimpleRule(args[0], args[1])
-			simpleRules = append(simpleRules, rule)
 		case 1:
 			base = args[0]
 			fallthrough
@@ -76,20 +75,31 @@ func rewriteParse(c *Controller) ([]rewrite.Rule, error) {
 						return nil, err
 					}
 					ifs = append(ifs, ifCond)
+				case "status":
+					if !c.NextArg() {
+						return nil, c.ArgErr()
+					}
+					status, _ = strconv.Atoi(c.Val())
+					if status < 400 || status > 499 {
+						return nil, c.Err("status must be 4xx")
+					}
 				default:
 					return nil, c.ArgErr()
 				}
 			}
-			// ensure to is specified
-			if to == "" {
+			// ensure to or status is specified
+			if to == "" && status == 0 {
 				return nil, c.ArgErr()
 			}
-			if rule, err = rewrite.NewComplexRule(base, pattern, to, ext, ifs); err != nil {
+			if rule, err = rewrite.NewComplexRule(base, pattern, to, status, ext, ifs); err != nil {
 				return nil, err
 			}
 			regexpRules = append(regexpRules, rule)
+
+		// the only unhandled case is 2 and above
 		default:
-			return nil, c.ArgErr()
+			rule = rewrite.NewSimpleRule(args[0], strings.Join(args[1:], " "))
+			simpleRules = append(simpleRules, rule)
 		}
 
 	}

caddy/setup/rewrite_test.go

@@ -50,8 +50,8 @@ func TestRewriteParse(t *testing.T) {
 		}},
 		{`rewrite a`, true, []rewrite.Rule{}},
 		{`rewrite`, true, []rewrite.Rule{}},
-		{`rewrite a b c`, true, []rewrite.Rule{
-			rewrite.SimpleRule{From: "a", To: "b"},
+		{`rewrite a b c`, false, []rewrite.Rule{
+			rewrite.SimpleRule{From: "a", To: "b c"},
 		}},
 	}
 
@@ -137,6 +137,33 @@ func TestRewriteParse(t *testing.T) {
 		 }`, false, []rewrite.Rule{
 			&rewrite.ComplexRule{Base: "/", To: "/to", Ifs: []rewrite.If{rewrite.If{A: "{path}", Operator: "is", B: "a"}}},
 		}},
+		{`rewrite {
+			status 400
+		 }`, false, []rewrite.Rule{
+			&rewrite.ComplexRule{Base: "/", Regexp: regexp.MustCompile(".*"), Status: 400},
+		}},
+		{`rewrite {
+			to /to
+			status 400
+		 }`, false, []rewrite.Rule{
+			&rewrite.ComplexRule{Base: "/", To: "/to", Regexp: regexp.MustCompile(".*"), Status: 400},
+		}},
+		{`rewrite {
+			status 399
+		 }`, true, []rewrite.Rule{
+			&rewrite.ComplexRule{},
+		}},
+		{`rewrite {
+			status 0
+		 }`, true, []rewrite.Rule{
+			&rewrite.ComplexRule{},
+		}},
+		{`rewrite {
+			to /to
+			status 0
+		 }`, true, []rewrite.Rule{
+			&rewrite.ComplexRule{},
+		}},
 	}
 
 	for i, test := range regexpTests {

middleware/rewrite/condition.go

@@ -14,9 +14,11 @@ const (
 	Is         = "is"
 	Not        = "not"
 	Has        = "has"
+	NotHas     = "not_has"
 	StartsWith = "starts_with"
 	EndsWith   = "ends_with"
 	Match      = "match"
+	NotMatch   = "not_match"
 )
 
 func operatorError(operator string) error {
@@ -34,9 +36,11 @@ var conditions = map[string]condition{
 	Is:         isFunc,
 	Not:        notFunc,
 	Has:        hasFunc,
+	NotHas:     notHasFunc,
 	StartsWith: startsWithFunc,
 	EndsWith:   endsWithFunc,
 	Match:      matchFunc,
+	NotMatch:   notMatchFunc,
 }
 
 // isFunc is condition for Is operator.
@@ -57,6 +61,12 @@ func hasFunc(a, b string) bool {
 	return strings.Contains(a, b)
 }
 
+// notHasFunc is condition for NotHas operator.
+// It checks if b is not a substring of a.
+func notHasFunc(a, b string) bool {
+	return !strings.Contains(a, b)
+}
+
 // startsWithFunc is condition for StartsWith operator.
 // It checks if b is a prefix of a.
 func startsWithFunc(a, b string) bool {
@@ -71,11 +81,20 @@ func endsWithFunc(a, b string) bool {
 
 // matchFunc is condition for Match operator.
 // It does regexp matching of a against pattern in b
+// and returns if they match.
 func matchFunc(a, b string) bool {
 	matched, _ := regexp.MatchString(b, a)
 	return matched
 }
 
+// notMatchFunc is condition for NotMatch operator.
+// It does regexp matching of a against pattern in b
+// and returns if they do not match.
+func notMatchFunc(a, b string) bool {
+	matched, _ := regexp.MatchString(b, a)
+	return !matched
+}
+
 // If is statement for a rewrite condition.
 type If struct {
 	A        string

middleware/rewrite/condition_test.go

@@ -20,6 +20,11 @@ func TestConditions(t *testing.T) {
 		{"ba has b", true},
 		{"bab has b", true},
 		{"bab has bb", false},
+		{"a not_has a", false},
+		{"a not_has b", true},
+		{"ba not_has b", false},
+		{"bab not_has b", false},
+		{"bab not_has bb", true},
 		{"bab starts_with bb", false},
 		{"bab starts_with ba", true},
 		{"bab starts_with bab", true},
@@ -37,6 +42,17 @@ func TestConditions(t *testing.T) {
 		{"b0a match b[a-z]", false},
 		{"b0a match b[a-z]+", false},
 		{"b0a match b[a-z0-9]+", true},
+		{"a not_match *", true},
+		{"a not_match a", false},
+		{"a not_match .*", false},
+		{"a not_match a.*", false},
+		{"a not_match b.*", true},
+		{"ba not_match b.*", false},
+		{"ba not_match b[a-z]", false},
+		{"b0 not_match b[a-z]", true},
+		{"b0a not_match b[a-z]", true},
+		{"b0a not_match b[a-z]+", true},
+		{"b0a not_match b[a-z0-9]+", false},
 	}
 
 	for i, test := range tests {

middleware/rewrite/rewrite.go

@@ -13,6 +13,19 @@ import (
 	"github.com/mholt/caddy/middleware"
 )
 
+// RewriteResult is the result of a rewrite
+type RewriteResult int
+
+const (
+	// RewriteIgnored is returned when rewrite is not done on request.
+	RewriteIgnored RewriteResult = iota
+	// RewriteDone is returned when rewrite is done on request.
+	RewriteDone
+	// RewriteStatus is returned when rewrite is not needed and status code should be set
+	// for the request.
+	RewriteStatus
+)
+
 // Rewrite is middleware to rewrite request locations internally before being handled.
 type Rewrite struct {
 	Next    middleware.Handler
@@ -22,9 +35,18 @@ type Rewrite struct {
 
 // ServeHTTP implements the middleware.Handler interface.
 func (rw Rewrite) ServeHTTP(w http.ResponseWriter, r *http.Request) (int, error) {
+outer:
 	for _, rule := range rw.Rules {
-		if ok := rule.Rewrite(rw.FileSys, r); ok {
+		switch result := rule.Rewrite(rw.FileSys, r); result {
+		case RewriteDone:
+			break outer
+		case RewriteIgnored:
 			break
+		case RewriteStatus:
+			// only valid for complex rules.
+			if cRule, ok := rule.(*ComplexRule); ok && cRule.Status != 0 {
+				return cRule.Status, nil
+			}
 		}
 	}
 	return rw.Next.ServeHTTP(w, r)
@@ -33,7 +55,7 @@ func (rw Rewrite) ServeHTTP(w http.ResponseWriter, r *http.Request) (int, error)
 // Rule describes an internal location rewrite rule.
 type Rule interface {
 	// Rewrite rewrites the internal location of the current request.
-	Rewrite(http.FileSystem, *http.Request) bool
+	Rewrite(http.FileSystem, *http.Request) RewriteResult
 }
 
 // SimpleRule is a simple rewrite rule.
@@ -47,7 +69,7 @@ func NewSimpleRule(from, to string) SimpleRule {
 }
 
 // Rewrite rewrites the internal location of the current request.
-func (s SimpleRule) Rewrite(fs http.FileSystem, r *http.Request) bool {
+func (s SimpleRule) Rewrite(fs http.FileSystem, r *http.Request) RewriteResult {
 	if s.From == r.URL.Path {
 		// take note of this rewrite for internal use by fastcgi
 		// all we need is the URI, not full URL
@@ -56,7 +78,7 @@ func (s SimpleRule) Rewrite(fs http.FileSystem, r *http.Request) bool {
 		// attempt rewrite
 		return To(fs, r, s.To, newReplacer(r))
 	}
-	return false
+	return RewriteIgnored
 }
 
 // ComplexRule is a rewrite rule based on a regular expression
@@ -67,6 +89,10 @@ type ComplexRule struct {
 	// Path to rewrite to
 	To string
 
+	// If set, neither performs rewrite nor proceeds
+	// with request. Only returns code.
+	Status int
+
 	// Extensions to filter by
 	Exts []string
 
@@ -78,7 +104,7 @@ type ComplexRule struct {
 
 // NewRegexpRule creates a new RegexpRule. It returns an error if regexp
 // pattern (pattern) or extensions (ext) are invalid.
-func NewComplexRule(base, pattern, to string, ext []string, ifs []If) (*ComplexRule, error) {
+func NewComplexRule(base, pattern, to string, status int, ext []string, ifs []If) (*ComplexRule, error) {
 	// validate regexp if present
 	var r *regexp.Regexp
 	if pattern != "" {
@@ -102,6 +128,7 @@ func NewComplexRule(base, pattern, to string, ext []string, ifs []If) (*ComplexR
 	return &ComplexRule{
 		Base:   base,
 		To:     to,
+		Status: status,
 		Exts:   ext,
 		Ifs:    ifs,
 		Regexp: r,
@@ -109,33 +136,33 @@ func NewComplexRule(base, pattern, to string, ext []string, ifs []If) (*ComplexR
 }
 
 // Rewrite rewrites the internal location of the current request.
-func (r *ComplexRule) Rewrite(fs http.FileSystem, req *http.Request) bool {
+func (r *ComplexRule) Rewrite(fs http.FileSystem, req *http.Request) (re RewriteResult) {
 	rPath := req.URL.Path
 	replacer := newReplacer(req)
 
 	// validate base
 	if !middleware.Path(rPath).Matches(r.Base) {
-		return false
+		return
 	}
 
 	// validate extensions
 	if !r.matchExt(rPath) {
-		return false
+		return
 	}
 
+	// validate regexp if present
+	if r.Regexp != nil {
 		// include trailing slash in regexp if present
 		start := len(r.Base)
 		if strings.HasSuffix(r.Base, "/") {
 			start--
 		}
 
-	// validate regexp if present
-	if r.Regexp != nil {
 		matches := r.FindStringSubmatch(rPath[start:])
 		switch len(matches) {
 		case 0:
 			// no match
-			return false
+			return
 		default:
 			// set regexp match variables {1}, {2} ...
 			for i := 1; i < len(matches); i++ {
@@ -147,8 +174,13 @@ func (r *ComplexRule) Rewrite(fs http.FileSystem, req *http.Request) bool {
 	// validate rewrite conditions
 	for _, i := range r.Ifs {
 		if !i.True(req) {
-			return false
+			return
+		}
 	}
+
+	// if status is present, stop rewrite and return it.
+	if r.Status != 0 {
+		return RewriteStatus
 	}
 
 	// attempt rewrite

middleware/rewrite/rewrite_test.go

@@ -41,7 +41,7 @@ func TestRewrite(t *testing.T) {
 		if s := strings.Split(regexpRule[3], "|"); len(s) > 1 {
 			ext = s[:len(s)-1]
 		}
-		rule, err := NewComplexRule(regexpRule[0], regexpRule[1], regexpRule[2], ext, nil)
+		rule, err := NewComplexRule(regexpRule[0], regexpRule[1], regexpRule[2], 0, ext, nil)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -106,6 +106,51 @@ func TestRewrite(t *testing.T) {
 				i, test.expectedTo, rec.Body.String())
 		}
 	}
+
+	statusTests := []struct {
+		status         int
+		base           string
+		to             string
+		regexp         string
+		statusExpected bool
+	}{
+		{400, "/status", "", "", true},
+		{400, "/ignore", "", "", false},
+		{400, "/", "", "^/ignore", false},
+		{400, "/", "", "(.*)", true},
+		{400, "/status", "", "", true},
+	}
+
+	for i, s := range statusTests {
+		urlPath := fmt.Sprintf("/status%d", i)
+		rule, err := NewComplexRule(s.base, s.regexp, s.to, s.status, nil, nil)
+		if err != nil {
+			t.Fatalf("Test %d: No error expected for rule but found %v", i, err)
+		}
+		rw.Rules = []Rule{rule}
+		req, err := http.NewRequest("GET", urlPath, nil)
+		if err != nil {
+			t.Fatalf("Test %d: Could not create HTTP request: %v", i, err)
+		}
+
+		rec := httptest.NewRecorder()
+		code, err := rw.ServeHTTP(rec, req)
+		if err != nil {
+			t.Fatalf("Test %d: No error expected for handler but found %v", i, err)
+		}
+		if s.statusExpected {
+			if rec.Body.String() != "" {
+				t.Errorf("Test %d: Expected empty body but found %s", i, rec.Body.String())
+			}
+			if code != s.status {
+				t.Errorf("Test %d: Expected status code %d found %d", i, s.status, code)
+			}
+		} else {
+			if code != 0 {
+				t.Errorf("Test %d: Expected no status code found %d", i, code)
+			}
+		}
+	}
 }
 
 func urlPrinter(w http.ResponseWriter, r *http.Request) (int, error) {

middleware/rewrite/to.go

@@ -13,7 +13,7 @@ import (
 // To attempts rewrite. It attempts to rewrite to first valid path
 // or the last path if none of the paths are valid.
 // Returns true if rewrite is successful and false otherwise.
-func To(fs http.FileSystem, r *http.Request, to string, replacer middleware.Replacer) bool {
+func To(fs http.FileSystem, r *http.Request, to string, replacer middleware.Replacer) RewriteResult {
 	tos := strings.Fields(to)
 
 	// try each rewrite paths
@@ -38,7 +38,7 @@ func To(fs http.FileSystem, r *http.Request, to string, replacer middleware.Repl
 		// Let the user know we got here. Rewrite is expected but
 		// the resulting url is invalid.
 		log.Printf("[ERROR] rewrite: resulting path '%v' is invalid. error: %v", t, err)
-		return false
+		return RewriteIgnored
 	}
 
 	// take note of this rewrite for internal use by fastcgi
@@ -56,7 +56,7 @@ func To(fs http.FileSystem, r *http.Request, to string, replacer middleware.Repl
 		r.URL.Fragment = u.Fragment
 	}
 
-	return true
+	return RewriteDone
 }
 
 // isValidFile checks if file exists on the filesystem.