feat: adds more levels parsing like [ error] with spaces (#2441)

docker/level_guesser.go

@@ -7,22 +7,30 @@ import (
 
 var KEY_VALUE_REGEX = regexp.MustCompile(`level=(\w+)`)
 var ANSI_COLOR_REGEX = regexp.MustCompile(`\x1b\[[0-9;]*m`)
+var LOG_LEVELS = []string{"error", "warn", "warning", "info", "debug", "trace", "fatal"}
+var LOG_LEVELS_PLAIN = map[string]*regexp.Regexp{}
+var LOG_LEVEL_BRACKET = map[string]*regexp.Regexp{}
+
+func init() {
+	for _, level := range LOG_LEVELS {
+		LOG_LEVELS_PLAIN[level] = regexp.MustCompile("(?i)^" + level + "[^a-z]")
+	}
+
+	for _, level := range LOG_LEVELS {
+		LOG_LEVEL_BRACKET[level] = regexp.MustCompile("(?i)^\\[ ?" + level + " ?\\]")
+	}
+}
 
 func guessLogLevel(logEvent *LogEvent) string {
 	switch value := logEvent.Message.(type) {
 	case string:
-		levels := []string{"error", "warn", "warning", "info", "debug", "trace", "fatal"}
 		stripped := ANSI_COLOR_REGEX.ReplaceAllString(value, "") // remove ansi color codes
-		for _, level := range levels {
-			if match, _ := regexp.MatchString("(?i)^"+level+"[^a-z]", stripped); match {
-				return level
-			}
-
-			if strings.Contains(value, "["+strings.ToUpper(level)+"]") {
+		for _, level := range LOG_LEVELS {
+			if LOG_LEVELS_PLAIN[level].MatchString(stripped) {
 				return level
 			}
 
-			if strings.Contains(value, "["+strings.ToLower(level)+"]") {
+			if LOG_LEVEL_BRACKET[level].MatchString(stripped) {
 				return level
 			}
 

docker/level_guesser_test.go

@@ -0,0 +1,37 @@
+package docker
+
+import (
+	"testing"
+)
+
+func TestGuessLogLevel(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected string
+	}{
+		{"ERROR: Something went wrong", "error"},
+		{"WARN: Something might be wrong", "warn"},
+		{"INFO: Something happened", "info"},
+		{"debug: Something happened", "debug"},
+		{"debug Something happened", "debug"},
+		{"TRACE: Something happened", "trace"},
+		{"FATAL: Something happened", "fatal"},
+		{"level=error Something went wrong", "error"},
+		{"[ERROR] Something went wrong", "error"},
+		{"[error] Something went wrong", "error"},
+		{"[ ERROR ] Something went wrong", "error"},
+		{"[error] Something went wrong", "error"},
+		{"123 ERROR Something went wrong", "error"},
+		{"123 Something went wrong", ""},
+	}
+
+	for _, test := range tests {
+		logEvent := &LogEvent{
+			Message: test.input,
+		}
+		if level := guessLogLevel(logEvent); level != test.expected {
+			t.Errorf("guessLogLevel(%s) = %s, want %s", test.input, level, test.expected)
+		}
+	}
+
+}