Add support for dynamic MDC with jakarta (modern javax)

logevents/pom.xml

@@ -54,6 +54,12 @@
             <version>3.1.0</version>
             <optional>true</optional>
         </dependency>
+        <dependency>
+            <groupId>jakarta.servlet</groupId>
+            <artifactId>jakarta.servlet-api</artifactId>
+            <version>6.0.0</version>
+            <optional>true</optional>
+        </dependency>
         <dependency>
             <groupId>com.microsoft.azure</groupId>
             <artifactId>applicationinsights-core</artifactId>

logevents/src/main/java/org/logevents/optional/jakarta/HttpServletMDC.java

@@ -0,0 +1,63 @@
+package org.logevents.optional.jakarta;
+
+import org.logevents.config.MdcFilter;
+import org.logevents.formatters.exceptions.ExceptionFormatter;
+import org.logevents.mdc.DynamicMDC;
+
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+import java.util.Map;
+import java.util.function.Supplier;
+
+/**
+ * Populates MDC or JSON format according to <a href="https://www.elastic.co/guide/en/ecs/current/">Elastic
+ * Common Schema</a> guidelines:
+ *
+ * <ul>
+ *     <li><strong>url.original:</strong> The URL as the user entered it</li>
+ *     <li><strong>http.request.method:</strong> GET, PUT, POST, DELETE etc</li>
+ *     <li><strong>user.name:</strong> {@link HttpServletRequest#getRemoteUser()}</li>
+ *     <li><strong>client.address:</strong> {@link HttpServletRequest#getRemoteAddr()}</li>
+ *     <li><strong>event.time:</strong> The number of seconds since the request started</li>
+ *     <li>
+ *         <strong>error.{class, message, stack_trace} (only JSON, not MDC)</strong>:
+ *          The exception in <code>"javax.servlet.error.exception"</code> (if any)
+ *     </li>
+ *     <li><strong>http.response.status_code</strong>: {@link HttpServletResponse#getStatus()}</li>
+ *     <li><strong>http.response.mime_type</strong>: {@link HttpServletResponse#getContentType()}</li>
+ *     <li><strong>http.response.redirect</strong>: "Location" response header</li>
+ * </ul>
+ */
+public class HttpServletMDC implements DynamicMDC {
+
+    private final HttpServletRequest request;
+    private final HttpServletResponse response;
+    private final long duration;
+
+    public HttpServletMDC(HttpServletRequest request, HttpServletResponse response, long duration) {
+        this.request = request;
+        this.response = response;
+        this.duration = duration;
+    }
+
+    public static Supplier<DynamicMDC> supplier(HttpServletRequest request, HttpServletResponse response) {
+        long start = System.currentTimeMillis();
+        return () -> new HttpServletMDC(request, response, System.currentTimeMillis() - start);
+    }
+
+    @Override
+    public Iterable<? extends Map.Entry<String, String>> entrySet() {
+        Map<String, String> result = new java.util.LinkedHashMap<>();
+        HttpServletResponseMDC.addMdcVariables(result, response);
+        HttpServletRequestMDC.addMdcVariables(result, request);
+        result.put("event.time", String.format("%.04f", duration / 1000.0));
+        return result.entrySet();
+    }
+
+    @Override
+    public void populateJsonEvent(Map<String, Object> jsonPayload, MdcFilter mdcFilter, ExceptionFormatter exceptionFormatter) {
+        HttpServletResponseMDC.populateJson(jsonPayload, response);
+        HttpServletRequestMDC.populateJson(jsonPayload, exceptionFormatter, request);
+        jsonPayload.put("event.time", String.format("%.04f", duration / 1000.0));
+    }
+}

logevents/src/main/java/org/logevents/optional/jakarta/HttpServletRequestMDC.java

@@ -0,0 +1,87 @@
+package org.logevents.optional.jakarta;
+
+import org.logevents.config.MdcFilter;
+import org.logevents.formatters.JsonLogEventFormatter;
+import org.logevents.formatters.exceptions.ExceptionFormatter;
+import org.logevents.mdc.DynamicMDC;
+import org.logevents.mdc.DynamicMDCAdapter;
+import org.logevents.util.JsonUtil;
+
+import jakarta.servlet.ServletRequest;
+import jakarta.servlet.http.HttpServletRequest;
+import java.util.Map;
+import java.util.function.Supplier;
+
+/**
+ * Populates MDC or JSON format according to <a href="https://www.elastic.co/guide/en/ecs/current/">Elastic
+ * Common Schema</a> guidelines:
+ *
+ * <ul>
+ *     <li><strong>url.original:</strong> The URL as the user entered it</li>
+ *     <li><strong>http.request.method:</strong> GET, PUT, POST, DELETE etc</li>
+ *     <li><strong>user.name:</strong> {@link HttpServletRequest#getRemoteUser()}</li>
+ *     <li><strong>client.address:</strong> {@link HttpServletRequest#getRemoteAddr()}</li>
+ *     <li><strong>event.time:</strong> The number of seconds since the request started</li>
+ *     <li>
+ *         <strong>error.{class, message, stack_trace} (only JSON, not MDC)</strong>:
+ *          The exception in <code>"javax.servlet.error.exception"</code> (if any)
+ *      </li>
+ * </ul>
+ */
+public class HttpServletRequestMDC implements DynamicMDC {
+
+    public static void addMdcVariables(Map<String, String> result, HttpServletRequest request) {
+        result.put("http.request.method", request.getMethod());
+        result.put("url.original", request.getRequestURL().toString());
+        result.put("user.name", request.getRemoteUser());
+        result.put("client.address", request.getRemoteHost());
+    }
+
+    public static void populateJson(Map<String, Object> jsonPayload, ExceptionFormatter exceptionFormatter, HttpServletRequest request) {
+        jsonPayload.put("url.original", request.getRequestURL().toString());
+        jsonPayload.put("user.name", request.getRemoteUser());
+        jsonPayload.put("client.address", request.getRemoteHost());
+
+        if (jsonPayload.containsKey("http")) {
+            JsonUtil.getObject(jsonPayload, "http").put("request.method", request.getMethod());
+        } else {
+            jsonPayload.put("http.request.method", request.getMethod());
+        }
+
+        if (request.getAttribute("javax.servlet.error.exception") instanceof Throwable) {
+            Throwable exception = (Throwable) request.getAttribute("javax.servlet.error.exception");
+            jsonPayload.put("error", JsonLogEventFormatter.toJsonObject(exception, exceptionFormatter));
+        }
+    }
+
+    private final HttpServletRequest request;
+    private final long duration;
+
+    private HttpServletRequestMDC(HttpServletRequest request, long duration) {
+        this.request = request;
+        this.duration = duration;
+    }
+
+    public static Supplier<DynamicMDC> supplier(HttpServletRequest request) {
+        long start = System.currentTimeMillis();
+        return () -> new HttpServletRequestMDC(request, System.currentTimeMillis() - start);
+    }
+
+    public static DynamicMDCAdapter.Cleanup put(ServletRequest request) {
+        return DynamicMDC.putDynamic("request", supplier((HttpServletRequest) request));
+    }
+
+    @Override
+    public Iterable<? extends Map.Entry<String, String>> entrySet() {
+        Map<String, String> result = new java.util.LinkedHashMap<>();
+        addMdcVariables(result, request);
+        result.put("event.time", String.format("%.04f", duration / 1000.0));
+        return result.entrySet();
+    }
+
+    @Override
+    public void populateJsonEvent(Map<String, Object> jsonPayload, MdcFilter mdcFilter, ExceptionFormatter exceptionFormatter) {
+        populateJson(jsonPayload, exceptionFormatter, request);
+        jsonPayload.put("event.time", String.format("%.04f", duration / 1000.0));
+    }
+}

logevents/src/main/java/org/logevents/optional/jakarta/HttpServletResponseMDC.java

@@ -0,0 +1,63 @@
+package org.logevents.optional.jakarta;
+
+import org.logevents.config.MdcFilter;
+import org.logevents.formatters.exceptions.ExceptionFormatter;
+import org.logevents.mdc.DynamicMDC;
+
+import jakarta.servlet.http.HttpServletResponse;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.function.Supplier;
+
+/**
+ * Populates MDC or JSON format according to <a href="https://www.elastic.co/guide/en/ecs/current/">Elastic
+ * Common Schema</a> guidelines:
+ *
+ * <ul>
+ * <li><strong>http.response.status_code</strong>: {@link HttpServletResponse#getStatus()}</li>
+ * <li><strong>http.response.mime_type</strong>: {@link HttpServletResponse#getContentType()}</li>
+ * <li><strong>http.response.redirect</strong>: "Location" response header</li>
+ * </ul>
+ */
+public class HttpServletResponseMDC implements DynamicMDC {
+
+    public static void populateJson(Map<String, Object> jsonPayload, HttpServletResponse response) {
+        Map<String, Object> http = new HashMap<>();
+
+        Map<String, Object> httpResponse = new HashMap<>();
+        httpResponse.put("status_code", response.getStatus());
+        httpResponse.put("mime_type", response.getContentType());
+        httpResponse.put("redirect", response.getHeader("Location"));
+
+        http.put("response", httpResponse);
+        jsonPayload.put("http", http);
+    }
+
+    public static void addMdcVariables(Map<String, String> result, HttpServletResponse response) {
+        result.put("http.response.status_code", String.valueOf(response.getStatus()));
+        result.put("http.response.mime_type", response.getContentType());
+        result.put("http.response.redirect", response.getHeader("Location"));
+    }
+
+    private final HttpServletResponse response;
+
+    public HttpServletResponseMDC(HttpServletResponse response) {
+        this.response = response;
+    }
+
+    public static Supplier<DynamicMDC> supplier(HttpServletResponse response) {
+        return () -> new HttpServletResponseMDC(response);
+    }
+
+    @Override
+    public Iterable<? extends Map.Entry<String, String>> entrySet() {
+        Map<String, String> result = new java.util.LinkedHashMap<>();
+        addMdcVariables(result, response);
+        return result.entrySet();
+    }
+
+    @Override
+    public void populateJsonEvent(Map<String, Object> jsonPayload, MdcFilter mdcFilter, ExceptionFormatter exceptionFormatter) {
+        populateJson(jsonPayload, response);
+    }
+}

logevents/src/main/java/org/logevents/optional/jakarta/LogEventsConfigurationServlet.java

@@ -0,0 +1,71 @@
+package org.logevents.optional.jakarta;
+
+import org.logevents.LogEventFactory;
+import org.logevents.LogEventLogger;
+import org.logevents.core.LogEventFilter;
+import org.logevents.util.JsonUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.slf4j.event.Level;
+
+import jakarta.servlet.http.HttpServlet;
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+
+public class LogEventsConfigurationServlet extends HttpServlet {
+
+    private static final Logger logger = LoggerFactory.getLogger(LogEventsConfigurationServlet.class);
+
+    @Override
+    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {
+        Map<String, Object> configuration = logConfigurationToJson(LogEventFactory.getInstance());
+        resp.setContentType("application/json");
+        resp.getWriter().println(JsonUtil.toIndentedJson(configuration));
+    }
+
+    Map<String, Object> logConfigurationToJson(LogEventFactory logEventFactory) {
+        Map<String, LogEventLogger> loggers = logEventFactory.getLoggers();
+
+        List<String> loggerNames = new ArrayList<>(loggers.keySet());
+        Collections.sort(loggerNames);
+
+        Map<String, String> logLevels = new LinkedHashMap<>();
+        // TODO: null check?
+        logLevels.put("/", logEventFactory.getRootLogger().getOwnFilter().toString());
+        for (String loggerName : loggerNames) {
+            LogEventFilter threshold = logEventFactory.getLogger(loggerName).getOwnFilter();
+            logLevels.put(loggerName, threshold != null ? threshold.toString() : "<inherited>");
+        }
+
+        Map<String, String> observers = new LinkedHashMap<>();
+        observers.put("/", logEventFactory.getRootLogger().getObserver());
+        for (String loggerName : loggerNames) {
+            observers.put(loggerName, logEventFactory.getLogger(loggerName).getObserver());
+        }
+
+        Map<String, Object> configuration = new LinkedHashMap<>();
+        configuration.put("logLevels", logLevels);
+        configuration.put("observers", observers);
+        return configuration;
+    }
+
+    @Override
+    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws IOException {
+        setLogLevel(req.getParameter("loggerName"), req.getParameter("level"));
+        resp.sendRedirect(req.getContextPath() + req.getServletPath() + req.getPathInfo());
+    }
+
+    void setLogLevel(String loggerName, String levelName) {
+        Level level = levelName == null || levelName.equals("null") ? null : Level.valueOf(levelName);
+        logger.info("Changing log level for {} to {}", loggerName, level);
+
+        LogEventFactory.getInstance().setLevel(loggerName, level);
+    }
+
+}