reverseproxy: Add `handle_response` blocks to `reverse_proxy` (#3710) (#4021)

* reverseproxy: Add `handle_response` blocks to `reverse_proxy` (#3710)

* reverseproxy: complete handle_response test

* reverseproxy: Change handle_response matchers to use named matchers

reverseproxy: Add support for changing status code

* fastcgi: Remove obsolete TODO

We already have d.Err("transport already specified") in the reverse_proxy parsing code which covers this case

* reverseproxy: Fix support for "4xx" type status codes

* Apply suggestions from code review

Co-authored-by: Matt Holt <mholt@users.noreply.github.com>

* caddyhttp: Reorganize response matchers

* reverseproxy: Reintroduce caddyfile.Unmarshaler

* reverseproxy: Add comment mentioning Finalize should be called

Co-authored-by: Maxime Soulé <btik-git@scoubidou.com>
Co-authored-by: Matt Holt <mholt@users.noreply.github.com>

1 files changed, 1 insertions, 68 deletions

diff --git a/modules/caddyhttp/encode/caddyfile.go b/modules/caddyhttp/encode/caddyfile.go
index c45f159..b236520 100644
--- a/modules/caddyhttp/encode/caddyfile.go
+++ b/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)