ContentFilteringSlf4jEventSender

ContentFilteringSlf4jEventSender.java

import org.apache.cxf.common.util.StringUtils;
import org.apache.cxf.ext.logging.event.LogEvent;
import org.apache.cxf.ext.logging.slf4j.Slf4jEventSender;
import org.apache.cxf.ext.logging.slf4j.Slf4jVerboseEventSender;
import org.slf4j.event.Level;

import javax.xml.namespace.QName;
import java.util.Set;
import java.util.regex.Pattern;

/**
 * Based on {@link Slf4jVerboseEventSender} and
 * https://stackoverflow.com/questions/23212313/cxf-logging-request-response-with-content-filtering-or-masking-soap-fields
 */
public class ContentFilteringSlf4jEventSender extends Slf4jEventSender {
    private static final String MASK_PATTERN = "<\\s*{}\\s*>(.*)</\\s*{}\\s*>|<\\s*name\\s*>\\s*{}\\s*</\\s*name\\s*>\\s*<\\s*value\\s*>(.*)<";
    private final Pattern pattern;

    public static ContentFilteringSlf4jEventSender of(Level loggingLevel, Set<String> sensitiveFields) {
        return new ContentFilteringSlf4jEventSender(loggingLevel, sensitiveFields);
    }

    private ContentFilteringSlf4jEventSender(Level loggingLevel, Set<String> sensitiveFields) {
        super.setLoggingLevel(loggingLevel);
        var patternBuilder = new StringBuilder();
        sensitiveFields.forEach(field -> {
            patternBuilder.append(MASK_PATTERN.replace("{}", field));
            patternBuilder.append("|");
        });
        patternBuilder.setLength(patternBuilder.length() - 1);
        pattern = Pattern.compile(patternBuilder.toString(), Pattern.CASE_INSENSITIVE | Pattern.MULTILINE);
    }

    @Override
    protected String getLogMessage(LogEvent event) {
        var b = new StringBuilder();
        // Start from the next line to have the output well-aligned
        b.append(event.getType()).append('\n');

        write(b, "Address", event.getAddress());
        write(b, "HttpMethod", event.getHttpMethod());
        write(b, "Content-Type", event.getContentType());
        write(b, "ResponseCode", event.getResponseCode());
        write(b, "ExchangeId", event.getExchangeId());
        if (event.getServiceName() != null) {
            write(b, "ServiceName", localPart(event.getServiceName()));
            write(b, "PortName", localPart(event.getPortName()));
            write(b, "PortTypeName", localPart(event.getPortTypeName()));
        }
        if (event.getFullContentFile() != null) {
            write(b, "FullContentFile", event.getFullContentFile().getAbsolutePath());
        }
        write(b, "Headers", event.getHeaders().toString());
        if (!StringUtils.isEmpty(event.getPayload())) {
            writePayload(b, event.getPayload());
        }
        return b.toString();
    }

    private void writePayload(StringBuilder b, String payload) {
        b.append('\n');
        var matcher = pattern.matcher(payload);
        var builder = new StringBuilder(payload);
        while (matcher.find()) {
            int group = 1;
            while (group <= matcher.groupCount()) {
                if (matcher.group(group) != null) {
                    for (int i = matcher.start(group); i < matcher.end(group); i++) {
                        builder.setCharAt(i, '*');
                    }
                }
                group++;
            }
        }
        b.append(builder.toString());
    }

    private static String localPart(QName name) {
        return name == null ? null : name.getLocalPart();
    }

    private static void write(StringBuilder b, String key, String value) {
        if (value != null) {
            b.append("    ").append(key).append(": ").append(value).append('\n');
        }
    }
}