I have different types of logs having a common pattern. What I intend to do is mask the value present in it with #.

cvc-length-valid: Value '9899488103' with length = '10' is not facet-valid with respect to length '20' for type 'customerId'.

cvc-pattern-valid: Value 'GB200102BUYFNBUYSN' is not facet-valid with respect to pattern '[A-Za-z]{2,2}(17|18|19|20|21)[0-9]{2}((0)[1-9]|(1)[012])((0)[1-9]|(1|2)[0-9]|(3)[01])[A-Za-z]{1}[A-Za-z#]{4}[A-Za-z]{1}[A-Za-z#]{4}' for type '#AnonType_NATIONAL_ID_CONCATbuyerSellerId'.

Expected Output

cvc-length-valid: Value '#####' with length = '10' is not facet-valid with respect to length '20' for type 'customerId'.
cvc-pattern-valid: Value '#####' is not facet-valid with respect to pattern '[A-Za-z]{2,2}(17|18|19|20|21)[0-9]{2}((0)[1-9]|(1)[012])((0)[1-9]|(1|2)[0-9]|(3)[01])[A-Za-z]{1}[A-Za-z#]{4}[A-Za-z]{1}[A-Za-z#]{4}' for type '#AnonType_NATIONAL_ID_CONCATbuyerSellerId'.

CodePudding user response：

You could try a regex replacement:

String input = "cvc-length-valid: Value '9899488103' with length = '10' is not facet-valid with respect to length '20' for type 'customerId'.";
String output = input.replaceAll("(\\S ): Value '.*?' (.*)", "$1: Value '#####' $2");
System.out.println(output);

This prints:

cvc-length-valid: Value '#####' with length = '10' is not facet-valid with respect to length '20' for type 'customerId'.

CodePudding user response：

One practice is to use LayoutWrappingEncoder and configuration class to read the masking patterns from the configuration and apply them in the log messages. This is rather a simple approach and can be achieved with a custom pattern handler.

The MaskingPatternLayout (Configuration) class to read patterns

public class MaskingPatternLayout extends PatternLayout {

    private Pattern multilinePattern;
    private List<String> maskPatterns = new ArrayList<>();

    public void addMaskPattern(String maskPattern) {
        maskPatterns.add(maskPattern);
        multilinePattern = Pattern.compile(maskPatterns.stream().collect(Collectors.joining("|")), Pattern.MULTILINE);
    }

    @Override
    public String doLayout(ILoggingEvent event) {
        return maskMessage(super.doLayout(event));
    }

    private String maskMessage(String message) {
        if (multilinePattern == null) {
            return message;
        }
        StringBuilder sb = new StringBuilder(message);
        Matcher matcher = multilinePattern.matcher(sb);
        while (matcher.find()) {
            IntStream.rangeClosed(1, matcher.groupCount()).forEach(group -> {
                if (matcher.group(group) != null) {
                    IntStream.range(matcher.start(group), matcher.end(group)).forEach(i -> sb.setCharAt(i, '#'));
                }
            });
        }
        return sb.toString();
    }
}

And pattern matcher(here i assumed we using Logback as log provider) as logback.xml file .

<configuration>
    <appender name="mask" >
        <encoder >
           <layout >
           <maskPattern>\"YOU mentioned log pattern\"</maskPattern>
         
            </layout>
        </encoder>
    </appender>
</ configuration>