Allow !~= for website/uri

cmd/frontend/filter.go

@@ -19,9 +19,11 @@ var andRe = regexp.MustCompile(`(?i)\s+and\s+`)
 //
 //	status=200  status!=200  status>=400  status>400  status<=500  status<500
 //	website=example.com      — exact match
-//	website~=gouda.*         — RE2 regex
+//	website~=gouda.*         — RE2 regex match
+//	website!~=gouda.*        — RE2 regex exclusion
 //	uri=/api/v1/             — exact match
-//	uri~=^/api/.*            — RE2 regex
+//	uri~=^/api/.*            — RE2 regex match
+//	uri!~=^/ct/.*            — RE2 regex exclusion
 //	prefix=1.2.3.0/24        — exact match
 //
 // Values may be enclosed in double or single quotes.
@@ -57,6 +59,8 @@ func applyTerm(term string, fs *filterState) error {
 
 	var op, value string
 	switch {
+	case strings.HasPrefix(rest, "!~="):
+		op, value = "!~=", rest[3:]
 	case strings.HasPrefix(rest, "~="):
 		op, value = "~=", rest[2:]
 	case strings.HasPrefix(rest, "!="):
@@ -96,8 +100,10 @@ func applyTerm(term string, fs *filterState) error {
 			fs.Website = value
 		case "~=":
 			fs.WebsiteRe = value
+		case "!~=":
+			fs.WebsiteReNeg = value
 		default:
-			return fmt.Errorf("website only supports = and ~=, not %q", op)
+			return fmt.Errorf("website only supports =, ~=, and !~=, not %q", op)
 		}
 	case "uri":
 		switch op {
@@ -105,8 +111,10 @@ func applyTerm(term string, fs *filterState) error {
 			fs.URI = value
 		case "~=":
 			fs.URIRe = value
+		case "!~=":
+			fs.URIReNeg = value
 		default:
-			return fmt.Errorf("uri only supports = and ~=, not %q", op)
+			return fmt.Errorf("uri only supports =, ~=, and !~=, not %q", op)
 		}
 	case "prefix":
 		if op != "=" {
@@ -164,6 +172,9 @@ func FilterExprString(f filterState) string {
 	if f.WebsiteRe != "" {
 		parts = append(parts, "website~="+quoteMaybe(f.WebsiteRe))
 	}
+	if f.WebsiteReNeg != "" {
+		parts = append(parts, "website!~="+quoteMaybe(f.WebsiteReNeg))
+	}
 	if f.Prefix != "" {
 		parts = append(parts, "prefix="+quoteMaybe(f.Prefix))
 	}
@@ -173,6 +184,9 @@ func FilterExprString(f filterState) string {
 	if f.URIRe != "" {
 		parts = append(parts, "uri~="+quoteMaybe(f.URIRe))
 	}
+	if f.URIReNeg != "" {
+		parts = append(parts, "uri!~="+quoteMaybe(f.URIReNeg))
+	}
 	if f.Status != "" {
 		parts = append(parts, statusTermStr(f.Status))
 	}