feat: add prefix monitor

spi/common/core-spi/src/main/java/org/eclipse/edc/spi/monitor/Monitor.java

@@ -9,6 +9,7 @@
  *
  *  Contributors:
  *       Microsoft Corporation - initial API and implementation
+ *       Mercedes-Benz Tech Innovation GmbH - prefix monitoring
  *
  */
 
@@ -64,4 +65,17 @@ default String sanitizeMessage(Supplier<String> supplier) {
                 .orElse(null);
     }
 
+    /**
+     * Creates a prefixed {@link Monitor} which will prepend the supplied prefix parameter to the actual log message
+     * in the format of: <strong>[LOGLEVEL] [TIMESTAMP] [[PREFIX]] [MESSAGE]</strong>
+     * <br>
+     * Example output: <strong>INFO 2023-11-08T15:53:39.989025 [JerseyExtension]: Registered Web API context alias: protocol</strong>
+     *
+     * @param prefix string value to be prefixed
+     * @return the prefixed monitor
+     */
+    default Monitor withPrefix(String prefix) {
+        return new PrefixMonitor(this, prefix);
+    }
+
 }

spi/common/core-spi/src/main/java/org/eclipse/edc/spi/monitor/PrefixMonitor.java

@@ -0,0 +1,74 @@
+/*
+ *  Copyright (c) 2023 Mercedes-Benz Tech Innovation GmbH
+ *
+ *  This program and the accompanying materials are made available under the
+ *  terms of the Apache License, Version 2.0 which is available at
+ *  https://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  SPDX-License-Identifier: Apache-2.0
+ *
+ *  Contributors:
+ *       Mercedes-Benz Tech Innovation GmbH -  initial implementation
+ *
+ */
+
+package org.eclipse.edc.spi.monitor;
+
+import java.util.function.Supplier;
+
+/**
+ * Monitor implementation which will prefix a supplied text to all log messages.
+ * Note that this monitor will delegate the actual log execution to the underlying monitor provided by the context.
+ */
+class PrefixMonitor implements Monitor {
+
+    private static final String MESSAGE_FORMAT = "[%s] %s";
+
+    private final Monitor monitor;
+    private final String prefix;
+
+    PrefixMonitor(Monitor monitor, String prefix) {
+        this.monitor = monitor;
+        this.prefix = prefix;
+    }
+
+    @Override
+    public void severe(Supplier<String> supplier, Throwable... errors) {
+        monitor.severe(() -> MESSAGE_FORMAT.formatted(prefix, supplier.get()), errors);
+    }
+
+    @Override
+    public void severe(String message, Throwable... errors) {
+        monitor.severe(MESSAGE_FORMAT.formatted(prefix, message), errors);
+    }
+
+    @Override
+    public void warning(Supplier<String> supplier, Throwable... errors) {
+        monitor.warning(() -> MESSAGE_FORMAT.formatted(prefix, supplier.get()), errors);
+    }
+
+    @Override
+    public void warning(String message, Throwable... errors) {
+        monitor.warning(MESSAGE_FORMAT.formatted(prefix, message), errors);
+    }
+
+    @Override
+    public void info(Supplier<String> supplier, Throwable... errors) {
+        monitor.info(() -> MESSAGE_FORMAT.formatted(prefix, supplier.get()), errors);
+    }
+
+    @Override
+    public void info(String message, Throwable... errors) {
+        monitor.info(MESSAGE_FORMAT.formatted(prefix, message), errors);
+    }
+
+    @Override
+    public void debug(Supplier<String> supplier, Throwable... errors) {
+        monitor.debug(() -> MESSAGE_FORMAT.formatted(prefix, supplier.get()), errors);
+    }
+
+    @Override
+    public void debug(String message, Throwable... errors) {
+        monitor.debug(MESSAGE_FORMAT.formatted(prefix, message), errors);
+    }
+}

spi/common/core-spi/src/test/java/org/eclipse/edc/spi/monitor/PrefixMonitorTest.java

@@ -0,0 +1,81 @@
+/*
+ *  Copyright (c) 2023 Mercedes-Benz Tech Innovation GmbH
+ *
+ *  This program and the accompanying materials are made available under the
+ *  terms of the Apache License, Version 2.0 which is available at
+ *  https://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  SPDX-License-Identifier: Apache-2.0
+ *
+ *  Contributors:
+ *       Mercedes-Benz Tech Innovation GmbH -  initial implementation
+ *
+ */
+
+package org.eclipse.edc.spi.monitor;
+
+import org.junit.jupiter.api.Test;
+import org.mockito.Mockito;
+
+import java.util.function.Supplier;
+
+import static org.mockito.ArgumentMatchers.argThat;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.verify;
+
+class PrefixMonitorTest {
+
+    private static final String TEST_PREFIX = "Test Prefix";
+    private static final String TEST_MESSAGE = "Test Message";
+    private static final String EXPECTED_MESSAGE = "[Test Prefix] Test Message";
+    private final Monitor mockMonitor = Mockito.mock();
+    private final Monitor prefixMonitor = new PrefixMonitor(mockMonitor, TEST_PREFIX);
+
+    @Test
+    void logSevere_byMessageSupplier_logIsDelegated() {
+        prefixMonitor.severe(() -> TEST_MESSAGE);
+        verify(mockMonitor).severe(argThat((Supplier<String> supplier) -> EXPECTED_MESSAGE.equals(supplier.get())));
+    }
+
+    @Test
+    void logSevere_byMessageString_logIsDelegated() {
+        prefixMonitor.severe(TEST_MESSAGE);
+        verify(mockMonitor).severe(eq(EXPECTED_MESSAGE));
+    }
+
+    @Test
+    void logWarning_byMessageSupplier_logIsDelegated() {
+        prefixMonitor.warning(() -> TEST_MESSAGE);
+        verify(mockMonitor).warning(argThat((Supplier<String> supplier) -> EXPECTED_MESSAGE.equals(supplier.get())));
+    }
+
+    @Test
+    void logWarning_byMessageString_logIsDelegated() {
+        prefixMonitor.warning(TEST_MESSAGE);
+        verify(mockMonitor).warning(eq(EXPECTED_MESSAGE));
+    }
+
+    @Test
+    void logInfo_byMessageSupplier_logIsDelegated() {
+        prefixMonitor.info(() -> TEST_MESSAGE);
+        verify(mockMonitor).info(argThat((Supplier<String> supplier) -> EXPECTED_MESSAGE.equals(supplier.get())));
+    }
+
+    @Test
+    void logInfo_byMessageString_logIsDelegated() {
+        prefixMonitor.info(TEST_MESSAGE);
+        verify(mockMonitor).info(eq(EXPECTED_MESSAGE));
+    }
+
+    @Test
+    void logDebug_byMessageSupplier_logIsDelegated() {
+        prefixMonitor.debug(() -> TEST_MESSAGE);
+        verify(mockMonitor).debug(argThat((Supplier<String> supplier) -> EXPECTED_MESSAGE.equals(supplier.get())));
+    }
+
+    @Test
+    void logDebug_byMessageString_logIsDelegated() {
+        prefixMonitor.debug(TEST_MESSAGE);
+        verify(mockMonitor).debug(eq(EXPECTED_MESSAGE));
+    }
+}