reverseproxy: Add handle_response blocks to reverse_proxy (#3710)

caddyconfig/httpcaddyfile/directives.go

@@ -265,6 +265,13 @@ func (h Helper) NewBindAddresses(addrs []string) []ConfigValue {
 	return []ConfigValue{{Class: "bind", Value: addrs}}
 }
 
+// WithDispenser returns a new instance based on d. All others Helper
+// fields are copied, so typically maps are shared with this new instance.
+func (h Helper) WithDispenser(d *caddyfile.Dispenser) Helper {
+	h.Dispenser = d
+	return h
+}
+
 // ParseSegmentAsSubroute parses the segment such that its subdirectives
 // are themselves treated as directives, from which a subroute is built
 // and returned.

caddytest/integration/caddyfile_adapt/reverse_proxy_handle_response.txt

@@ -0,0 +1,193 @@
+:8884
+
+reverse_proxy 127.0.0.1:65535 {
+	@accel header X-Accel-Redirect *
+	handle_response @accel {
+		respond "Header X-Accel-Redirect!"
+	}
+
+	@another {
+		header X-Another *
+	}
+	handle_response @another {
+		respond "Header X-Another!"
+	}
+
+	@401 status 401
+	handle_response @401 {
+		respond "Status 401!"
+	}
+
+	handle_response {
+		respond "Any! This should be last in the JSON!"
+	}
+
+	@403 {
+		status 403
+	}
+	handle_response @403 {
+		respond "Status 403!"
+	}
+
+	@multi {
+		status 401 403
+		status 404
+		header Foo *
+		header Bar *
+	}
+	handle_response @multi {
+		respond "Headers Foo, Bar AND statuses 401, 403 and 404!"
+	}
+
+	@changeStatus status 500
+	handle_response @changeStatus 400
+}
+----------
+{
+	"apps": {
+		"http": {
+			"servers": {
+				"srv0": {
+					"listen": [
+						":8884"
+					],
+					"routes": [
+						{
+							"handle": [
+								{
+									"handle_response": [
+										{
+											"match": {
+												"headers": {
+													"X-Accel-Redirect": [
+														"*"
+													]
+												}
+											},
+											"routes": [
+												{
+													"handle": [
+														{
+															"body": "Header X-Accel-Redirect!",
+															"handler": "static_response"
+														}
+													]
+												}
+											]
+										},
+										{
+											"match": {
+												"headers": {
+													"X-Another": [
+														"*"
+													]
+												}
+											},
+											"routes": [
+												{
+													"handle": [
+														{
+															"body": "Header X-Another!",
+															"handler": "static_response"
+														}
+													]
+												}
+											]
+										},
+										{
+											"match": {
+												"status_code": [
+													401
+												]
+											},
+											"routes": [
+												{
+													"handle": [
+														{
+															"body": "Status 401!",
+															"handler": "static_response"
+														}
+													]
+												}
+											]
+										},
+										{
+											"match": {
+												"status_code": [
+													403
+												]
+											},
+											"routes": [
+												{
+													"handle": [
+														{
+															"body": "Status 403!",
+															"handler": "static_response"
+														}
+													]
+												}
+											]
+										},
+										{
+											"match": {
+												"headers": {
+													"Bar": [
+														"*"
+													],
+													"Foo": [
+														"*"
+													]
+												},
+												"status_code": [
+													401,
+													403,
+													404
+												]
+											},
+											"routes": [
+												{
+													"handle": [
+														{
+															"body": "Headers Foo, Bar AND statuses 401, 403 and 404!",
+															"handler": "static_response"
+														}
+													]
+												}
+											]
+										},
+										{
+											"match": {
+												"status_code": [
+													500
+												]
+											},
+											"status_code": 400
+										},
+										{
+											"routes": [
+												{
+													"handle": [
+														{
+															"body": "Any! This should be last in the JSON!",
+															"handler": "static_response"
+														}
+													]
+												}
+											]
+										}
+									],
+									"handler": "reverse_proxy",
+									"upstreams": [
+										{
+											"dial": "127.0.0.1:65535"
+										}
+									]
+								}
+							]
+						}
+					]
+				}
+			}
+		}
+	}
+}

modules/caddyhttp/encode/caddyfile.go

@@ -15,9 +15,7 @@
 package encode
 
 import (
-	"net/http"
 	"strconv"
-	"strings"
 
 	"github.com/caddyserver/caddy/v2"
 	"github.com/caddyserver/caddy/v2/caddyconfig"
@@ -95,7 +93,7 @@ func (enc *Encode) UnmarshalCaddyfile(d *caddyfile.Dispenser) error {
 				}
 				enc.Prefer = encs
 			case "match":
-				err := enc.parseNamedResponseMatcher(d.NewFromNextSegment(), responseMatchers)
+				err := caddyhttp.ParseNamedResponseMatcher(d.NewFromNextSegment(), responseMatchers)
 				if err != nil {
 					return err
 				}
@@ -123,70 +121,5 @@ func (enc *Encode) UnmarshalCaddyfile(d *caddyfile.Dispenser) error {
 	return nil
 }
 
-// Parse the tokens of a named response matcher.
-//
-//     match {
-//         header <field> [<value>]
-//         status <code...>
-//     }
-//
-// Or, single line syntax:
-//
-//     match [header <field> [<value>]] | [status <code...>]
-//
-func (enc *Encode) parseNamedResponseMatcher(d *caddyfile.Dispenser, matchers map[string]caddyhttp.ResponseMatcher) error {
-	for d.Next() {
-		definitionName := d.Val()
-
-		if _, ok := matchers[definitionName]; ok {
-			return d.Errf("matcher is defined more than once: %s", definitionName)
-		}
-
-		matcher := caddyhttp.ResponseMatcher{}
-		for nesting := d.Nesting(); d.NextArg() || d.NextBlock(nesting); {
-			switch d.Val() {
-			case "header":
-				if matcher.Headers == nil {
-					matcher.Headers = http.Header{}
-				}
-
-				// reuse the header request matcher's unmarshaler
-				headerMatcher := caddyhttp.MatchHeader(matcher.Headers)
-				err := headerMatcher.UnmarshalCaddyfile(d.NewFromNextSegment())
-				if err != nil {
-					return err
-				}
-
-				matcher.Headers = http.Header(headerMatcher)
-			case "status":
-				if matcher.StatusCode == nil {
-					matcher.StatusCode = []int{}
-				}
-
-				args := d.RemainingArgs()
-				if len(args) == 0 {
-					return d.ArgErr()
-				}
-
-				for _, arg := range args {
-					if len(arg) == 3 && strings.HasSuffix(arg, "xx") {
-						arg = arg[:1]
-					}
-					statusNum, err := strconv.Atoi(arg)
-					if err != nil {
-						return d.Errf("bad status value '%s': %v", arg, err)
-					}
-					matcher.StatusCode = append(matcher.StatusCode, statusNum)
-				}
-			default:
-				return d.Errf("unrecognized response matcher %s", d.Val())
-			}
-		}
-
-		matchers[definitionName] = matcher
-	}
-	return nil
-}
-
 // Interface guard
 var _ caddyfile.Unmarshaler = (*Encode)(nil)

modules/caddyhttp/matchers.go

@@ -971,40 +971,6 @@ func (mre *MatchRegexp) UnmarshalCaddyfile(d *caddyfile.Dispenser) error {
 	return nil
 }
 
-// ResponseMatcher is a type which can determine if an
-// HTTP response matches some criteria.
-type ResponseMatcher struct {
-	// If set, one of these status codes would be required.
-	// A one-digit status can be used to represent all codes
-	// in that class (e.g. 3 for all 3xx codes).
-	StatusCode []int `json:"status_code,omitempty"`
-
-	// If set, each header specified must be one of the
-	// specified values, with the same logic used by the
-	// request header matcher.
-	Headers http.Header `json:"headers,omitempty"`
-}
-
-// Match returns true if the given statusCode and hdr match rm.
-func (rm ResponseMatcher) Match(statusCode int, hdr http.Header) bool {
-	if !rm.matchStatusCode(statusCode) {
-		return false
-	}
-	return matchHeaders(hdr, rm.Headers, "", nil)
-}
-
-func (rm ResponseMatcher) matchStatusCode(statusCode int) bool {
-	if rm.StatusCode == nil {
-		return true
-	}
-	for _, code := range rm.StatusCode {
-		if StatusCodeMatches(statusCode, code) {
-			return true
-		}
-	}
-	return false
-}
-
 var wordRE = regexp.MustCompile(`\w+`)
 
 const regexpPlaceholderPrefix = "http.regexp"