fixed unit tests relying on old SLF4J "Binder" mechanism

Signed-off-by: Thomas Jäckle <thomas.jaeckle@beyonnex.io>

internal/utils/pekko/src/test/java/org/eclipse/ditto/internal/utils/pekko/logging/CapturingMdcAdapterObserver.java

@@ -45,6 +45,11 @@ public void onPut(final String key, final String value) {
         allPutEntries.add(entry(key, value));
     }
 
+    @Override
+    public void onPushByKey(final String key, final String value) {
+        super.onPushByKey(key, value);
+    }
+
     @Override
     public void onRemove(final String key) {
         allRemovedKeys.add(key);

internal/utils/pekko/src/test/java/org/eclipse/ditto/internal/utils/pekko/logging/DefaultAutoCloseableSlf4jLoggerTest.java

@@ -19,6 +19,7 @@
 import org.assertj.core.api.JUnitSoftAssertions;
 import org.junit.After;
 import org.junit.Before;
+import org.junit.BeforeClass;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.TestName;
@@ -28,6 +29,7 @@
 import org.mockito.junit.MockitoJUnitRunner;
 import org.slf4j.Logger;
 import org.slf4j.impl.ObservableMdcAdapter;
+import org.slf4j.impl.StaticMDCServiceProvider;
 
 /**
  * Unit test for {@link DefaultAutoCloseableSlf4jLogger}.
@@ -49,6 +51,11 @@ public final class DefaultAutoCloseableSlf4jLoggerTest {
 
     private CapturingMdcAdapterObserver mdcObserver;
 
+    @BeforeClass
+    public static void configureProvider() {
+        System.setProperty("slf4j.provider", StaticMDCServiceProvider.class.getName());
+    }
+
     @Before
     public void setUp() {
         mdcObserver = new CapturingMdcAdapterObserver();

internal/utils/pekko/src/test/java/org/eclipse/ditto/internal/utils/pekko/logging/DefaultDittoLoggerTest.java

@@ -19,6 +19,7 @@
 import org.assertj.core.api.JUnitSoftAssertions;
 import org.junit.After;
 import org.junit.Before;
+import org.junit.BeforeClass;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.TestName;
@@ -28,6 +29,7 @@
 import org.mockito.junit.MockitoJUnitRunner;
 import org.slf4j.Logger;
 import org.slf4j.impl.ObservableMdcAdapter;
+import org.slf4j.impl.StaticMDCServiceProvider;
 
 /**
  * Unit test for {@link DefaultDittoLogger}.
@@ -49,6 +51,11 @@ public final class DefaultDittoLoggerTest {
 
     private CapturingMdcAdapterObserver mdcObserver;
 
+    @BeforeClass
+    public static void configureProvider() {
+        System.setProperty("slf4j.provider", StaticMDCServiceProvider.class.getName());
+    }
+
     @Before
     public void setUp() {
         mdcObserver = new CapturingMdcAdapterObserver();

internal/utils/pekko/src/test/java/org/eclipse/ditto/internal/utils/pekko/logging/ImmutableDittoLoggerTest.java

@@ -27,6 +27,7 @@
 import org.assertj.core.data.MapEntry;
 import org.junit.After;
 import org.junit.Before;
+import org.junit.BeforeClass;
 import org.junit.Ignore;
 import org.junit.Rule;
 import org.junit.Test;
@@ -37,6 +38,7 @@
 import org.mockito.junit.MockitoJUnitRunner;
 import org.slf4j.Logger;
 import org.slf4j.impl.ObservableMdcAdapter;
+import org.slf4j.impl.StaticMDCServiceProvider;
 
 /**
  * Unit test for {@link ImmutableDittoLogger}.
@@ -58,6 +60,11 @@ public final class ImmutableDittoLoggerTest {
 
     private CapturingMdcAdapterObserver mdcObserver;
 
+    @BeforeClass
+    public static void configureProvider() {
+        System.setProperty("slf4j.provider", StaticMDCServiceProvider.class.getName());
+    }
+
     @Before
     public void setUp() {
         mdcObserver = new CapturingMdcAdapterObserver();

internal/utils/pekko/src/test/java/org/slf4j/impl/ObservableMdcAdapter.java

@@ -104,21 +104,25 @@ public void setContextMap(final Map<String, String> contextMap) {
 
     @Override
     public void pushByKey(final String key, final String value) {
+        notifyAllObservers(observer -> observer.onPushByKey(key, value));
         basicMdcAdapter.pushByKey(key, value);
     }
 
     @Override
     public String popByKey(final String key) {
+        notifyAllObservers(observer -> observer.onPopByKey(key));
         return basicMdcAdapter.popByKey(key);
     }
 
     @Override
     public Deque<String> getCopyOfDequeByKey(final String key) {
+        notifyAllObservers(observer -> observer.onGetCopyOfDequeByKey(key));
         return basicMdcAdapter.getCopyOfDequeByKey(key);
     }
 
     @Override
     public void clearDequeByKey(final String key) {
+        notifyAllObservers(observer -> observer.onClearDequeByKey(key));
         basicMdcAdapter.clearDequeByKey(key);
     }
 
@@ -142,6 +146,13 @@ public interface MdcAdapterObserver {
 
         void onSetContextMap(Map<String, String> contextMap);
 
+        void onPushByKey(String key, String value);
+
+        void onPopByKey(String key);
+
+        void onGetCopyOfDequeByKey(String key);
+
+        void onClearDequeByKey(String key);
     }
 
     /**
@@ -187,6 +198,25 @@ public void onSetContextMap(final Map<String, String> contextMap) {
             // Does nothing by default.
         }
 
+        @Override
+        public void onPushByKey(final String key, final String value) {
+            // Does nothing by default.
+        }
+
+        @Override
+        public void onPopByKey(final String key) {
+            // Does nothing by default.
+        }
+
+        @Override
+        public void onGetCopyOfDequeByKey(final String key) {
+            // Does nothing by default.
+        }
+
+        @Override
+        public void onClearDequeByKey(final String key) {
+            // Does nothing by default.
+        }
     }
 
 }

internal/utils/pekko/src/test/java/org/slf4j/impl/StaticMDCServiceProvider.java

@@ -0,0 +1,60 @@
+/*
+ * Copyright (c) 2023 Contributors to the Eclipse Foundation
+ *
+ * See the NOTICE file(s) distributed with this work for additional
+ * information regarding copyright ownership.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package org.slf4j.impl;
+
+import javax.annotation.concurrent.Immutable;
+
+import org.slf4j.ILoggerFactory;
+import org.slf4j.IMarkerFactory;
+import org.slf4j.helpers.BasicMarkerFactory;
+import org.slf4j.helpers.NOPLoggerFactory;
+import org.slf4j.helpers.NOP_FallbackServiceProvider;
+import org.slf4j.spi.MDCAdapter;
+import org.slf4j.spi.SLF4JServiceProvider;
+
+/**
+ * The purpose of this class is to use {@link ObservableMdcAdapter} as MDC adapter for logging.
+ *
+ * @since 1.3.0
+ */
+@Immutable
+public final class StaticMDCServiceProvider implements SLF4JServiceProvider {
+
+    private final ILoggerFactory loggerFactory = new NOPLoggerFactory();
+    private final IMarkerFactory markerFactory = new BasicMarkerFactory();
+
+    @Override
+    public ILoggerFactory getLoggerFactory() {
+        return loggerFactory;
+    }
+
+    @Override
+    public IMarkerFactory getMarkerFactory() {
+        return markerFactory;
+    }
+
+    @Override
+    public MDCAdapter getMDCAdapter() {
+        return ObservableMdcAdapter.getInstance();
+    }
+
+    @Override
+    public String getRequestedApiVersion() {
+        return NOP_FallbackServiceProvider.REQUESTED_API_VERSION;
+    }
+
+    @Override
+    public void initialize() {
+        // already initialized
+    }
+}