Cleanup: Use Envoy contains for header routing (#5585)

Fixes #5572

Signed-off-by: Sotiris Nanopoulos <[email protected]>

Author: davinci26

internal/envoy/v3/route.go

@@ -17,7 +17,6 @@ import (
 	"bytes"
 	"fmt"
 	"net/http"
-	"regexp"
 	"sort"
 	"strings"
 	"text/template"
@@ -825,23 +824,11 @@ func queryParamMatcher(queryParams []dag.QueryParamMatchCondition) []*envoy_rout
 // containsMatch returns a HeaderMatchSpecifier which will match the
 // supplied substring
 func containsMatch(s string, ignoreCase bool) *envoy_route_v3.HeaderMatcher_StringMatch {
-	// convert the substring s into a regular expression that matches s.
-	// note that Envoy expects the expression to match the entire string, not just the substring
-	// formed from s. see [projectcontour/contour/#1751 & envoyproxy/envoy#8283]
-	var regex string
-	if ignoreCase {
-		regex = fmt.Sprintf("(?i).*%s.*", regexp.QuoteMeta(s))
-	} else {
-		regex = fmt.Sprintf(".*%s.*", regexp.QuoteMeta(s))
-	}
-
-	// This could also be implemented with contains envoy Matcher but the problem
-	// would be that it will be a breaking change for contour due to the way the
-	// envoy handles empty strings.
 	return &envoy_route_v3.HeaderMatcher_StringMatch{
 		StringMatch: &matcher.StringMatcher{
-			MatchPattern: &matcher.StringMatcher_SafeRegex{
-				SafeRegex: SafeRegexMatch(regex),
+			IgnoreCase: ignoreCase,
+			MatchPattern: &matcher.StringMatcher_Contains{
+				Contains: s,
 			},
 		},
 	}

internal/envoy/v3/route_test.go

@@ -1872,8 +1872,8 @@ func TestRouteMatch(t *testing.T) {
 					InvertMatch: false,
 					HeaderMatchSpecifier: &envoy_route_v3.HeaderMatcher_StringMatch{
 						StringMatch: &matcher.StringMatcher{
-							MatchPattern: &matcher.StringMatcher_SafeRegex{
-								SafeRegex: SafeRegexMatch(".*11-22-33-44.*"),
+							MatchPattern: &matcher.StringMatcher_Contains{
+								Contains: "11-22-33-44",
 							},
 						},
 					},
@@ -1895,8 +1895,8 @@ func TestRouteMatch(t *testing.T) {
 					InvertMatch: false,
 					HeaderMatchSpecifier: &envoy_route_v3.HeaderMatcher_StringMatch{
 						StringMatch: &matcher.StringMatcher{
-							MatchPattern: &matcher.StringMatcher_SafeRegex{
-								SafeRegex: SafeRegexMatch(".*11\\.22\\.33\\.44.*"),
+							MatchPattern: &matcher.StringMatcher_Contains{
+								Contains: "11.22.33.44",
 							},
 						},
 					},
@@ -1918,8 +1918,8 @@ func TestRouteMatch(t *testing.T) {
 					InvertMatch: false,
 					HeaderMatchSpecifier: &envoy_route_v3.HeaderMatcher_StringMatch{
 						StringMatch: &matcher.StringMatcher{
-							MatchPattern: &matcher.StringMatcher_SafeRegex{
-								SafeRegex: SafeRegexMatch(".*11\\.\\[22\\]\\.\\*33\\.44.*"),
+							MatchPattern: &matcher.StringMatcher_Contains{
+								Contains: "11.[22].*33.44",
 							},
 						},
 					},
@@ -2141,8 +2141,8 @@ func TestRouteMatch(t *testing.T) {
 					Name: "x-header-foo",
 					HeaderMatchSpecifier: &envoy_route_v3.HeaderMatcher_StringMatch{
 						StringMatch: &matcher.StringMatcher{
-							MatchPattern: &matcher.StringMatcher_SafeRegex{
-								SafeRegex: SafeRegexMatch(".*bar.*"),
+							MatchPattern: &matcher.StringMatcher_Contains{
+								Contains: "bar",
 							},
 						},
 					},
@@ -2163,8 +2163,9 @@ func TestRouteMatch(t *testing.T) {
 					Name: "x-header-foo",
 					HeaderMatchSpecifier: &envoy_route_v3.HeaderMatcher_StringMatch{
 						StringMatch: &matcher.StringMatcher{
-							MatchPattern: &matcher.StringMatcher_SafeRegex{
-								SafeRegex: SafeRegexMatch("(?i).*bar.*"),
+							IgnoreCase: true,
+							MatchPattern: &matcher.StringMatcher_Contains{
+								Contains: "bar",
 							},
 						},
 					},