commit for version used in evaluation of thesis

internal/drain3/masking.go

@@ -0,0 +1,32 @@
+// Package drain3 provides log stripping via regex-based masking templates which
+// sits in front of Drain3 template mining.
+package drain3
+
+import (
+	"codeberg.org/pata1704/guenther/internal/config"
+)
+
+// ApplyMasking applies all MaskingPatterns sequentially to line.
+//
+// For each pattern with a non-empty Name, capture group 1 of the regex is
+// stored in params before the match is replaced with mp.Replace.
+// Patterns without a Name only mask; they never write to params.
+//
+// All patterns are pre-compiled via config.Compile at startup;
+// no compilation happens in this hot-path function.
+func ApplyMasking(line string, patterns []config.MaskingPattern) (masked string, params map[string]string) {
+	params = make(map[string]string, len(patterns))
+	masked = line
+	for _, mp := range patterns {
+		if mp.Re == nil {
+			continue
+		}
+		if mp.Name != "" {
+			if m := mp.Re.FindStringSubmatch(masked); len(m) > 1 {
+				params[mp.Name] = m[1]
+			}
+		}
+		masked = mp.Re.ReplaceAllString(masked, mp.Replace)
+	}
+	return masked, params
+}