Sling log interceptor

core/pom.xml

@@ -149,10 +149,6 @@ DynamicImport-Package: *
             <groupId>org.osgi</groupId>
             <artifactId>org.osgi.service.event</artifactId>
         </dependency>
-        <dependency>
-            <groupId>org.osgi</groupId>
-            <artifactId>org.osgi.service.log</artifactId>
-        </dependency>
         <dependency>
             <groupId>org.osgi</groupId>
             <artifactId>org.osgi.framework</artifactId>
@@ -172,12 +168,10 @@ DynamicImport-Package: *
             <artifactId>slf4j-api</artifactId>
         </dependency>
         <dependency>
-            <groupId>ch.qos.logback</groupId>
-            <artifactId>logback-classic</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>ch.qos.logback</groupId>
-            <artifactId>logback-core</artifactId>
+            <groupId>org.apache.sling</groupId>
+            <artifactId>org.apache.sling.commons.classloader</artifactId>
+            <version>1.4.2</version>
+            <scope>provided</scope>
         </dependency>
         <dependency>
             <groupId>javax.jcr</groupId>

core/src/main/java/dev/vml/es/acm/core/code/CodePrintStream.java

@@ -1,10 +1,9 @@
 package dev.vml.es.acm.core.code;
 
-import ch.qos.logback.classic.Logger;
-import ch.qos.logback.classic.LoggerContext;
-import ch.qos.logback.classic.spi.ILoggingEvent;
-import ch.qos.logback.core.AppenderBase;
 import dev.vml.es.acm.core.AcmException;
+import dev.vml.es.acm.core.code.log.LogInterceptor;
+import dev.vml.es.acm.core.code.log.LogInterceptorManager;
+import dev.vml.es.acm.core.code.log.LogMessage;
 import java.io.OutputStream;
 import java.io.PrintStream;
 import java.time.Instant;
@@ -15,6 +14,7 @@
 import java.util.List;
 import java.util.Set;
 import org.apache.commons.lang3.StringUtils;
+import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
@@ -32,84 +32,71 @@ public class CodePrintStream extends PrintStream {
 
     private final Logger logger;
 
-    private final LoggerContext loggerContext;
+    private final LogInterceptorManager logInterceptorManager;
 
     private final Set<String> loggerNames;
 
     private boolean loggerTimestamps;
 
-    private final LogAppender logAppender;
+    private LogInterceptor.Handle interceptorHandle;
 
     private boolean printerTimestamps;
 
-    public CodePrintStream(OutputStream output, String id) {
+    public CodePrintStream(OutputStream output, String id, LogInterceptorManager logInterceptorManager) {
         super(output);
 
-        this.loggerContext = (LoggerContext) LoggerFactory.getILoggerFactory();
+        this.logInterceptorManager = logInterceptorManager;
         this.loggerNames = new HashSet<>();
         this.loggerTimestamps = true;
-        this.logger = loggerContext.getLogger(id);
-        this.logAppender = new LogAppender();
-
+        this.logger = LoggerFactory.getLogger(id);
         this.printerTimestamps = true;
     }
 
-    private class LogAppender extends AppenderBase<ILoggingEvent> {
-        @Override
-        protected void append(ILoggingEvent event) {
-            String loggerName = event.getLoggerName();
-            for (String loggerPrefix : loggerNames) {
-                if (StringUtils.startsWith(loggerName, loggerPrefix)) {
-                    String level = event.getLevel().toString();
-                    if (loggerTimestamps) {
-                        LocalDateTime eventTime = LocalDateTime.ofInstant(
-                                Instant.ofEpochMilli(event.getTimeStamp()), ZoneId.systemDefault());
-                        String timestamp = eventTime.format(TIMESTAMP_FORMATTER);
-                        println(timestamp + " [" + level + "] " + event.getFormattedMessage());
-                    } else {
-                        println('[' + level + "] " + event.getFormattedMessage());
-                    }
-                    break;
-                }
-            }
-        }
-    }
-
     public void fromLogger(String loggerName) {
         if (StringUtils.isBlank(loggerName)) {
             throw new AcmException("Logger name cannot be blank!");
         }
-        enableAppender();
         loggerNames.add(loggerName);
+        updateInterceptor();
     }
 
     @Override
     public void close() {
-        disableAppender();
+        detachInterceptor();
         super.close();
     }
 
-    private void enableAppender() {
-        if (logAppender.isStarted()) {
-            return;
+    private void updateInterceptor() {
+        detachInterceptor();
+        if (!loggerNames.isEmpty() && logInterceptorManager != null) {
+            interceptorHandle =
+                    logInterceptorManager.attach(this::handleLogMessage, loggerNames.toArray(new String[0]));
         }
-        Logger rootLogger = getRootLogger();
-        rootLogger.addAppender(logAppender);
-        logAppender.setContext(loggerContext);
-        logAppender.start();
     }
 
-    private void disableAppender() {
-        if (!logAppender.isStarted()) {
-            return;
+    private void detachInterceptor() {
+        if (interceptorHandle != null) {
+            interceptorHandle.detach();
+            interceptorHandle = null;
         }
-        logAppender.stop();
-        Logger rootLogger = getRootLogger();
-        rootLogger.detachAppender(logAppender);
     }
 
-    private Logger getRootLogger() {
-        return loggerContext.getLogger(Logger.ROOT_LOGGER_NAME);
+    private void handleLogMessage(LogMessage event) {
+        String loggerName = event.getLoggerName();
+        for (String loggerPrefix : loggerNames) {
+            if (StringUtils.startsWith(loggerName, loggerPrefix)) {
+                String level = event.getLevel();
+                if (loggerTimestamps) {
+                    LocalDateTime eventTime =
+                            LocalDateTime.ofInstant(Instant.ofEpochMilli(event.getTimestamp()), ZoneId.systemDefault());
+                    String timestamp = eventTime.format(TIMESTAMP_FORMATTER);
+                    println(timestamp + " [" + level + "] " + event.getMessage());
+                } else {
+                    println('[' + level + "] " + event.getMessage());
+                }
+                break;
+            }
+        }
     }
 
     public Logger getLogger() {

core/src/main/java/dev/vml/es/acm/core/code/ExecutionContext.java

@@ -1,6 +1,7 @@
 package dev.vml.es.acm.core.code;
 
 import dev.vml.es.acm.core.AcmConstants;
+import dev.vml.es.acm.core.code.log.LogInterceptorManager;
 import dev.vml.es.acm.core.repo.Repo;
 import dev.vml.es.acm.core.util.ResolverUtils;
 import groovy.lang.Binding;
@@ -70,7 +71,13 @@ public ExecutionContext(
         this.inputValues = inputValues;
         this.codeContext = codeContext;
         this.codeOutput = codeOutput;
-        this.printStream = new CodePrintStream(codeOutput.write(), String.format("%s|%s", executable.getId(), id));
+        this.printStream = new CodePrintStream(
+                codeOutput.write(),
+                String.format("%s|%s", executable.getId(), id),
+                codeContext
+                        .getOsgiContext()
+                        .findService(LogInterceptorManager.class)
+                        .orElse(null));
         this.schedules = new Schedules();
         this.conditions = new Conditions(this);
         this.inputs = new Inputs();

core/src/main/java/dev/vml/es/acm/core/code/log/LogInterceptor.java

@@ -0,0 +1,21 @@
+package dev.vml.es.acm.core.code.log;
+
+import java.util.function.Consumer;
+
+/**
+ * Intercepts log messages from specified loggers for automatic capture in script output.
+ *
+ * <p>Opt-in feature controlled by {@link dev.vml.es.acm.core.code.Executor.Config#logPrintingEnabled()}.
+ * Scripts can always log manually via SLF4J regardless of this setting.</p>
+ */
+public interface LogInterceptor {
+
+    boolean isAvailable();
+
+    Handle attach(Consumer<LogMessage> listener, String... loggerNames);
+
+    @FunctionalInterface
+    interface Handle {
+        void detach();
+    }
+}

core/src/main/java/dev/vml/es/acm/core/code/log/LogInterceptorManager.java

@@ -0,0 +1,55 @@
+package dev.vml.es.acm.core.code.log;
+
+import java.util.List;
+import java.util.concurrent.CopyOnWriteArrayList;
+import java.util.function.Consumer;
+import org.osgi.service.component.annotations.*;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Selects the best available {@link LogInterceptor} implementation.
+ *
+ * <p><strong>Why not OSGi Log Service 1.4?</strong> Its {@code LogReaderService} only captures
+ * logs sent directly to OSGi Log Service. SLF4J/Logback logs are bridged one-way (SLF4J → OSGi),
+ * so {@code LogReaderService} doesn't receive them. We use Sling AppenderTracker instead.</p>
+ *
+ * @see SlingLogInterceptor
+ */
+@Component(service = LogInterceptorManager.class)
+public class LogInterceptorManager {
+
+    private static final Logger LOG = LoggerFactory.getLogger(LogInterceptorManager.class);
+
+    private final List<LogInterceptor> interceptors = new CopyOnWriteArrayList<>();
+
+    @Reference(
+            service = LogInterceptor.class,
+            cardinality = ReferenceCardinality.MULTIPLE,
+            policy = ReferencePolicy.DYNAMIC)
+    protected void bindInterceptor(LogInterceptor interceptor) {
+        interceptors.add(interceptor);
+    }
+
+    protected void unbindInterceptor(LogInterceptor interceptor) {
+        interceptors.remove(interceptor);
+    }
+
+    public LogInterceptor.Handle attach(Consumer<LogMessage> listener, String... loggerNames) {
+        return interceptors.stream()
+                .filter(LogInterceptor::isAvailable)
+                .findFirst()
+                .map(i -> {
+                    LOG.debug("Using log interceptor: {}", i.getClass().getSimpleName());
+                    return i.attach(listener, loggerNames);
+                })
+                .orElseGet(() -> {
+                    LOG.warn("No log interceptor available");
+                    return () -> {};
+                });
+    }
+
+    public boolean isAvailable() {
+        return interceptors.stream().anyMatch(LogInterceptor::isAvailable);
+    }
+}

core/src/main/java/dev/vml/es/acm/core/code/log/LogMessage.java

@@ -0,0 +1,35 @@
+package dev.vml.es.acm.core.code.log;
+
+public class LogMessage {
+
+    private final String loggerName;
+
+    private final String level;
+
+    private final String message;
+
+    private final long timestamp;
+
+    public LogMessage(String loggerName, String level, String message, long timestamp) {
+        this.loggerName = loggerName;
+        this.level = level;
+        this.message = message;
+        this.timestamp = timestamp;
+    }
+
+    public String getLoggerName() {
+        return loggerName;
+    }
+
+    public String getLevel() {
+        return level;
+    }
+
+    public String getMessage() {
+        return message;
+    }
+
+    public long getTimestamp() {
+        return timestamp;
+    }
+}