review

modules/caddyhttp/fileserver/matcher.go

@@ -431,7 +431,7 @@ func (m MatchFile) selectFile(r *http.Request) (bool, error) {
 	// match file according to the configured policy
 	switch m.TryPolicy {
 	case "", tryPolicyFirstExist, tryPolicyFirstExistFallback:
-		var maxI int
+		maxI := -1
 		if m.TryPolicy == tryPolicyFirstExistFallback {
 			maxI = len(m.TryFiles) - 1
 		}

modules/caddyhttp/reverseproxy/fastcgi/caddyfile.go

@@ -18,6 +18,7 @@ import (
 	"encoding/json"
 	"net/http"
 	"strconv"
+	"strings"
 
 	"github.com/caddyserver/caddy/v2"
 	"github.com/caddyserver/caddy/v2/caddyconfig"
@@ -332,16 +333,20 @@ func parsePHPFastCGI(h httpcaddyfile.Helper) ([]httpcaddyfile.ConfigValue, error
 			HandlersRaw:    []json.RawMessage{caddyconfig.JSONModuleObject(redirHandler, "handler", "static_response", nil)},
 		}
 
+		tryPolicy := "first_exist_fallback"
 		// if tryFiles wasn't overridden, use a reasonable default
 		if len(tryFiles) == 0 {
 			tryFiles = []string{"{http.request.uri.path}", "{http.request.uri.path}/" + indexFile, indexFile}
+		} else if !strings.HasSuffix(tryFiles[len(tryFiles)-1], ".php") {
+			// use first_exist strategy if the last file is not a PHP file
+			tryPolicy = ""
 		}
 
 		// route to rewrite to PHP index file
 		rewriteMatcherSet := caddy.ModuleMap{
 			"file": h.JSON(fileserver.MatchFile{
 				TryFiles:  tryFiles,
-				TryPolicy: "first_exist_fallback",
+				TryPolicy: tryPolicy,
 				SplitPath: extensions,
 			}),
 		}