feat: Add ext-auth plugin support for authentication blacklists/whitelists (#1694)

plugins/wasm-go/extensions/ext-auth/expr/repeated_string_matcher.go

@@ -0,0 +1,76 @@
+package expr
+
+import (
+	"errors"
+
+	"github.com/tidwall/gjson"
+)
+
+type repeatedStringMatcher struct {
+	matchers []Matcher
+}
+
+func (rsm *repeatedStringMatcher) Match(s string) bool {
+	for _, m := range rsm.matchers {
+		if m.Match(s) {
+			return true
+		}
+	}
+	return false
+}
+
+func buildRepeatedStringMatcher(matchers []gjson.Result, allIgnoreCase bool) (Matcher, error) {
+	builtMatchers := make([]Matcher, len(matchers))
+
+	createMatcher := func(json gjson.Result, targetKey string, ignoreCase bool, constructor MatcherConstructor) (Matcher, error) {
+		result := json.Get(targetKey)
+		if result.Exists() && result.String() != "" {
+			target := result.String()
+			return constructor(target, ignoreCase)
+		}
+		return nil, nil
+	}
+
+	for i, item := range matchers {
+		var matcher Matcher
+		var err error
+
+		// If allIgnoreCase is true, it takes precedence over any user configuration,
+		// forcing case-insensitive matching regardless of individual item settings.
+		ignoreCase := allIgnoreCase
+		if !allIgnoreCase {
+			ignoreCaseResult := item.Get(MatchIgnoreCase)
+			if ignoreCaseResult.Exists() && ignoreCaseResult.Bool() {
+				ignoreCase = true
+			}
+		}
+
+		for key, creator := range matcherConstructors {
+			if matcher, err = createMatcher(item, key, ignoreCase, creator); err != nil {
+				return nil, err
+			}
+			if matcher != nil {
+				break
+			}
+		}
+
+		if matcher == nil {
+			return nil, errors.New("unknown string matcher type")
+		}
+
+		builtMatchers[i] = matcher
+
+	}
+
+	return &repeatedStringMatcher{
+		matchers: builtMatchers,
+	}, nil
+}
+
+func BuildRepeatedStringMatcherIgnoreCase(matchers []gjson.Result) (Matcher, error) {
+	return buildRepeatedStringMatcher(matchers, true)
+}
+
+func BuildRepeatedStringMatcher(matchers []gjson.Result) (Matcher, error) {
+	return buildRepeatedStringMatcher(matchers, false)
+}