Added logging context service, refactoring

Change-Id: Ib040d4579107b60c8da2c7a6da829f49c1cd8dd4
Issue-ID: SDC-772
Signed-off-by: vempo <vitaliy.emporopulo@amdocs.com>

11 files changed, 689 insertions, 373 deletions

diff --git a/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/LoggerFactory.java b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/LoggerFactory.java
index 1be2fa21dc..b790a02042 100644
--- a/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/LoggerFactory.java
+++ b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/LoggerFactory.java
@@ -4,9 +4,9 @@
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- * 
+ *
  *      http://www.apache.org/licenses/LICENSE-2.0
- * 
+ *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -16,245 +16,244 @@
 
 package org.openecomp.sdc.logging.api;
 
+import org.openecomp.sdc.logging.provider.LoggerCreationService;
+
+import java.util.Objects;
 
 /**
  * <a>Factory to hide a concrete, framework-specific implementation of logger creation.</a>
  * <p>The service used by this factory must implement {@link LoggerCreationService}. If no
- * implementation has been configured or could not be instantiated, a <b>no-op logger</b> will be
+ * implementation has been configured or could be instantiated, a <b>no-op logger</b> will be
  * used, and <b>no events</b> will be logged. This is done to prevent recursion if attempts are
  * being made to log exceptions that resulted from logger initialization. </p>
  *
  * @author evitaliy
- * @see BaseFactory
- * @see LoggerCreationService
  * @since 13/09/2016.
+ *
+ * @see ServiceBinder
+ * @see LoggerCreationService
  */
-@SuppressWarnings("ThrowableInstanceNeverThrown")
-public class LoggerFactory extends BaseFactory {
-
-  private static final LoggerCreationService SERVICE;
+public class LoggerFactory {
 
-  static {
-    LoggerCreationService service;
+    // use the no-op service to prevent recursion in case of an attempt to log an exception as a
+    // result of a logger initialization error
+    private static final LoggerCreationService SERVICE = ServiceBinder.getCreationServiceBinding().orElse(
+            new NoOpLoggerCreationService());
 
-    try {
-      service = locateService(LoggerCreationService.class);
-    } catch (Exception ex) {
-      new RuntimeException("Failed to instantiate logger factory", ex).printStackTrace();
-      // use the no-op service to prevent recursion in case of an attempt to log an exception as a
-      // result of a logger initialization error
-      service = new NoOpLoggerCreationService();
+    private LoggerFactory() {
+        // prevent instantiation
     }
 
-    SERVICE = service;
-  }
-
-  public static Logger getLogger(String clazzName) {
-    return SERVICE.getLogger(clazzName);
-  }
-
-  public static Logger getLogger(Class<?> clazz) {
-    return SERVICE.getLogger(clazz);
-  }
-
-  private static class NoOpLoggerCreationService implements LoggerCreationService {
-    private static final Logger NO_OP_LOGGER = new NoOpLogger();
-
-    private static class NoOpLogger implements Logger {
-      @Override
-      public String getName() {
-        return "No-Op Logger";
-      }
-
-      @Override
-      public boolean isMetricsEnabled() {
-        return false;
-      }
-
-      @Override
-      public void metrics(String msg) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void metrics(String msg, Object arg) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void metrics(String msg, Object arg1, Object arg2) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void metrics(String msg, Object... arguments) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void metrics(String msg, Throwable t) {
-        //this is no_op_method
-      }
-
-      @Override
-      public boolean isAuditEnabled() {
-        return false;
-      }
-
-      @Override
-      public void audit(String msg) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void audit(String msg, Object arg) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void audit(String msg, Object arg1, Object arg2) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void audit(String msg, Object... arguments) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void audit(String msg, Throwable t) {
-        //this is no_op_method
-      }
-
-      @Override
-      public boolean isDebugEnabled() {
-        return false;
-      }
-
-      @Override
-      public void debug(String msg) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void debug(String msg, Object arg) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void debug(String msg, Object arg1, Object arg2) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void debug(String msg, Object... arguments) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void debug(String msg, Throwable t) {
-        //this is no_op_method
-      }
-
-      @Override
-      public boolean isInfoEnabled() {
-        return false;
-      }
-
-      @Override
-      public void info(String msg) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void info(String msg, Object arg) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void info(String msg, Object arg1, Object arg2) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void info(String msg, Object... arguments) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void info(String msg, Throwable t) {
-        //this is no_op_method
-      }
-
-      @Override
-      public boolean isWarnEnabled() {
-        return false;
-      }
-
-      @Override
-      public void warn(String msg) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void warn(String msg, Object arg) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void warn(String msg, Object... arguments) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void warn(String msg, Object arg1, Object arg2) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void warn(String msg, Throwable t) {
-        //this is no_op_method
-      }
-
-      @Override
-      public boolean isErrorEnabled() {
-        return false;
-      }
-
-      @Override
-      public void error(String msg) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void error(String msg, Object arg) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void error(String msg, Object arg1, Object arg2) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void error(String msg, Object... arguments) {
-        //this is no_op_method
-      }
-
-      @Override
-      public void error(String msg, Throwable t) {
-        //this is no_op_method
-      }
+    public static Logger getLogger(String clazzName) {
+        return SERVICE.getLogger(clazzName);
     }
 
-    @Override
-    public Logger getLogger(String className) {
-      return NO_OP_LOGGER;
+    public static Logger getLogger(Class<?> clazz) {
+        return SERVICE.getLogger(clazz);
     }
 
-    @Override
-    public Logger getLogger(Class<?> clazz) {
-      return NO_OP_LOGGER;
+    private static class NoOpLoggerCreationService implements LoggerCreationService {
+
+        private static final Logger NO_OP_LOGGER = new NoOpLogger();
+
+        private static class NoOpLogger implements Logger {
+
+            @Override
+            public String getName() {
+                return "No-Op Logger";
+            }
+
+            @Override
+            public boolean isMetricsEnabled() {
+                return false;
+            }
+
+            @Override
+            public void metrics(String msg) {
+                // no-op
+            }
+
+            @Override
+            public void metrics(String msg, Object arg) {
+                // no-op
+            }
+
+            @Override
+            public void metrics(String msg, Object arg1, Object arg2) {
+                // no-op
+            }
+
+            @Override
+            public void metrics(String msg, Object... arguments) {
+                // no-op
+            }
+
+            @Override
+            public void metrics(String msg, Throwable t) {
+                // no-op
+            }
+
+            @Override
+            public boolean isAuditEnabled() {
+                return false;
+            }
+
+            @Override
+            public void audit(String msg) {
+                // no-op
+            }
+
+            @Override
+            public void audit(String msg, Object arg) {
+                // no-op
+            }
+
+            @Override
+            public void audit(String msg, Object arg1, Object arg2) {
+                // no-op
+            }
+
+            @Override
+            public void audit(String msg, Object... arguments) {
+                // no-op
+            }
+
+            @Override
+            public void audit(String msg, Throwable t) {
+                // no-op
+            }
+
+            @Override
+            public boolean isDebugEnabled() {
+                return false;
+            }
+
+            @Override
+            public void debug(String msg) {
+                // no-op
+            }
+
+            @Override
+            public void debug(String msg, Object arg) {
+                // no-op
+            }
+
+            @Override
+            public void debug(String msg, Object arg1, Object arg2) {
+                // no-op
+            }
+
+            @Override
+            public void debug(String msg, Object... arguments) {
+                // no-op
+            }
+
+            @Override
+            public void debug(String msg, Throwable t) {
+                // no-op
+            }
+
+            @Override
+            public boolean isInfoEnabled() {
+                return false;
+            }
+
+            @Override
+            public void info(String msg) {
+                // no-op
+            }
+
+            @Override
+            public void info(String msg, Object arg) {
+                // no-op
+            }
+
+            @Override
+            public void info(String msg, Object arg1, Object arg2) {
+                // no-op
+            }
+
+            @Override
+            public void info(String msg, Object... arguments) {
+                // no-op
+            }
+
+            @Override
+            public void info(String msg, Throwable t) {
+                // no-op
+            }
+
+            @Override
+            public boolean isWarnEnabled() {
+                return false;
+            }
+
+            @Override
+            public void warn(String msg) {
+                // no-op
+            }
+
+            @Override
+            public void warn(String msg, Object arg) {
+                // no-op
+            }
+
+            @Override
+            public void warn(String msg, Object... arguments) {
+                // no-op
+            }
+
+            @Override
+            public void warn(String msg, Object arg1, Object arg2) {
+                // no-op
+            }
+
+            @Override
+            public void warn(String msg, Throwable t) {
+                // no-op
+            }
+
+            @Override
+            public boolean isErrorEnabled() {
+                return false;
+            }
+
+            @Override
+            public void error(String msg) {
+                // no-op
+            }
+
+            @Override
+            public void error(String msg, Object arg) {
+                // no-op
+            }
+
+            @Override
+            public void error(String msg, Object arg1, Object arg2) {
+                // no-op
+            }
+
+            @Override
+            public void error(String msg, Object... arguments) {
+                // no-op
+            }
+
+            @Override
+            public void error(String msg, Throwable t) {
+                // no-op
+            }
+        }
+
+        @Override
+        public Logger getLogger(String className) {
+            Objects.requireNonNull(className, "Name cannot be null");
+            return NO_OP_LOGGER;
+        }
+
+        @Override
+        public Logger getLogger(Class<?> clazz) {
+            Objects.requireNonNull(clazz, "Class cannot be null");
+            return NO_OP_LOGGER;
+        }
     }
-  }
 }
diff --git a/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/LoggingContext.java b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/LoggingContext.java
new file mode 100644
index 0000000000..542f709074
--- /dev/null
+++ b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/LoggingContext.java
@@ -0,0 +1,109 @@
+/*
+ * Copyright © 2016-2017 European Support Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.openecomp.sdc.logging.api;
+
+import org.openecomp.sdc.logging.provider.LoggingContextService;
+
+import java.util.Objects;
+import java.util.concurrent.Callable;
+
+/**
+ * <a>Factory to hide a concrete, framework-specific implementation of diagnostic context.</a>
+ * <p>The service used by this factory must implement {@link LoggingContextService}. If no
+ * implementation has been configured or could be instantiated, a <b>no-op context service</b> will be
+ * used, and <b>no context</b> will be stored or propagated. No errors will be generated, so that the application can
+ * still work (albeit without proper logging).</p>
+ *
+ * @author evitaliy
+ * @since 07/01/2018.
+ *
+ * @see ServiceBinder
+ * @see LoggingContextService
+ */
+public class LoggingContext {
+
+    private static final LoggingContextService SERVICE = ServiceBinder.getContextServiceBinding().orElse(
+            new NoOpLoggingContextService());
+
+    private LoggingContext() {
+        // prevent instantiation
+    }
+
+    public static void put(String key, String value) {
+        SERVICE.put(key, value);
+    }
+
+    public static String get(String key) {
+        return SERVICE.get(key);
+    }
+
+    public static void remove(String key) {
+        SERVICE.remove(key);
+    }
+
+    public static void clear() {
+        SERVICE.clear();
+    }
+
+    public static Runnable toRunnable(Runnable runnable) {
+        return SERVICE.toRunnable(runnable);
+    }
+
+    public static <V> Callable<V> toCallable(Callable<V> callable) {
+        return SERVICE.toCallable(callable);
+    }
+
+    private static class NoOpLoggingContextService implements LoggingContextService {
+
+        private static final String KEY_CANNOT_BE_NULL = "Key cannot be null";
+
+        @Override
+        public void put(String key, String value) {
+            Objects.requireNonNull(key, KEY_CANNOT_BE_NULL);
+            // no-op
+        }
+
+        @Override
+        public String get(String key) {
+            Objects.requireNonNull(key, KEY_CANNOT_BE_NULL);
+            return null;
+        }
+
+        @Override
+        public void remove(String key) {
+            Objects.requireNonNull(key, KEY_CANNOT_BE_NULL);
+            // no-op
+        }
+
+        @Override
+        public void clear() {
+            // no-op
+        }
+
+        @Override
+        public Runnable toRunnable(Runnable runnable) {
+            Objects.requireNonNull(runnable, "Runnable cannot be null");
+            return runnable;
+        }
+
+        @Override
+        public <V> Callable<V> toCallable(Callable<V> callable) {
+            Objects.requireNonNull(callable, "Callable cannot be null");
+            return callable;
+        }
+    }
+}
diff --git a/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/ServiceBinder.java b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/ServiceBinder.java
new file mode 100644
index 0000000000..b16f3944e9
--- /dev/null
+++ b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/ServiceBinder.java
@@ -0,0 +1,93 @@
+/*
+ * Copyright © 2016-2017 European Support Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.openecomp.sdc.logging.api;
+
+import org.openecomp.sdc.logging.provider.LoggerCreationService;
+import org.openecomp.sdc.logging.provider.LoggingContextService;
+import org.openecomp.sdc.logging.provider.LoggingServiceProvider;
+
+import java.util.Iterator;
+import java.util.Optional;
+import java.util.ServiceLoader;
+
+/**
+ * <p>Binds to a concrete implementation of logging services.</p>
+ *
+ * <p>In order to use the factory, a particular (e.g. framework-specific) implementation of a service must be
+ * configured as described in
+ * <a href="http://docs.oracle.com/javase/8/docs/api/java/util/ServiceLoader.html">java.util.ServiceLoader</a>).</p>
+ *
+ * @author evitaliy
+ * @since 13/09/2016.
+ *
+ * @see ServiceLoader
+ */
+
+// No advanced logging can be used here because we don't know
+// which underlying implementation will be used
+@SuppressWarnings({"UseOfSystemOutOrSystemErr", "squid:S106"})
+class ServiceBinder {
+
+    private static final LoggingServiceProvider PROVIDER = lookupProvider();
+
+    private ServiceBinder () {
+        // prevent instantiation
+    }
+
+    private static LoggingServiceProvider lookupProvider() {
+
+        ServiceLoader<LoggingServiceProvider> loader = ServiceLoader.load(LoggingServiceProvider.class);
+        Iterator<LoggingServiceProvider> iterator = loader.iterator();
+
+        if (!iterator.hasNext()) {
+            System.err.printf("[ERROR] No provider configured for logging services %s. " +
+                            "Default implementation will be used.\n",
+                    LoggingServiceProvider.class.getName());
+            return null;
+        }
+
+        try {
+
+            LoggingServiceProvider provider = iterator.next();
+            if (!iterator.hasNext()) {
+                return provider;
+            }
+
+            Logger logger = provider.getLogger(ServiceBinder.class);
+            if (logger.isWarnEnabled()) {
+                logger.warn("More than one provider for logging services {} found",
+                        LoggingServiceProvider.class.getName());
+            }
+
+            return provider;
+
+        } catch (Exception e) {
+            // don't fail if the provider cannot be instantiated
+            e.printStackTrace(System.err);
+            return null;
+        }
+    }
+
+    static Optional<LoggingContextService> getContextServiceBinding() {
+        return Optional.ofNullable(PROVIDER);
+    }
+
+    static Optional<LoggerCreationService> getCreationServiceBinding() {
+        return Optional.ofNullable(PROVIDER);
+    }
+}
+
diff --git a/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/context/TaskFactory.java b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/context/TaskFactory.java
deleted file mode 100644
index 8621638460..0000000000
--- a/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/context/TaskFactory.java
+++ /dev/null
@@ -1,71 +0,0 @@
-/*
- * Copyright © 2016-2017 European Support Limited
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- * 
- *      http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.openecomp.sdc.logging.api.context;
-
-import org.openecomp.sdc.logging.api.BaseFactory;
-
-/**
- * <p>Should be used to propagate a diagnostic context (for instance <a
- * href="http://www.slf4j.org/manual.html#mdc">MDC</a>) to other threads.</p>
- * <p>Applicable when creating a child thread directly, or submitting tasks for potentially
- * postponed execution via an <a href="http://docs.oracle.com/javase/8/docs/api/java/util/concurrent/Executor.html">Executor</a>
- * (including any of the <a href="http://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ExecutorService.html">executor
- * services</a> and <a href="http://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ForkJoinPool.html">ForkJoinPool</a>).</p>
- * <p>The service used by this factory must implement {@link ContextPropagationService}.</p>
- *
- * @author evitaliy
- * @see ContextPropagationService
- * @since 12/09/2016.
- */
-@SuppressWarnings("ThrowableInstanceNeverThrown")
-public class TaskFactory extends BaseFactory {
-
-  private static final ContextPropagationService SERVICE;
-  private static final RuntimeException ERROR;
-
-  static {
-
-    ContextPropagationService service = null;
-    RuntimeException error = null;
-
-    try {
-      service = locateService(ContextPropagationService.class);
-    } catch (Exception ex) {
-      error = new RuntimeException("Failed to instantiate task factory", ex);
-    }
-
-    SERVICE = service;
-    ERROR = error;
-  }
-
-  /**
-   * Modify a task so that a diagnostic context is propagated to the thread when the task runs. Done
-   * in a logging-framework specific way.
-   *
-   * @param task any Runnable that will run in a thread
-   * @return modified (wrapped) original task that runs the same business logic, but also takes care
-   * of copying the diagnostic context for logging
-   */
-  public static Runnable create(Runnable task) {
-
-    if (SERVICE == null) {
-      throw ERROR;
-    }
-
-    return SERVICE.create(task);
-  }
-}
diff --git a/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/LoggerCreationService.java b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/provider/LoggerCreationService.java
index 1d8eda255e..344d23688e 100644
--- a/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/LoggerCreationService.java
+++ b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/provider/LoggerCreationService.java
@@ -14,7 +14,10 @@
  * limitations under the License.
  */
 
-package org.openecomp.sdc.logging.api;
+package org.openecomp.sdc.logging.provider;
+
+import org.openecomp.sdc.logging.api.Logger;
+import org.openecomp.sdc.logging.api.LoggerFactory;
 
 /**
  *
diff --git a/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/provider/LoggingContextService.java b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/provider/LoggingContextService.java
new file mode 100644
index 0000000000..8e725e7cc5
--- /dev/null
+++ b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/provider/LoggingContextService.java
@@ -0,0 +1,70 @@
+/*
+ * Copyright © 2016-2017 European Support Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.openecomp.sdc.logging.provider;
+
+import java.util.concurrent.Callable;
+
+/**
+ * Should be used to implement a framework-specific mechanism of managing a per-thread diagnostic context
+ * (for instance <a href="http://www.slf4j.org/manual.html#mdc">MDC</a>), and propagating it to child threads if needed.
+ * Context propagation should be used when creating a child thread directly, or submitting tasks for potentially
+ * postponed execution via an
+ * <a href="http://docs.oracle.com/javase/8/docs/api/java/util/concurrent/Executor.html">Executor</a> (including any of
+ * the
+ * <a href="http://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ExecutorService.html">executor services</a>
+ * and <a href="http://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ForkJoinPool.html">ForkJoinPool</a>).
+ *
+ * @author evitaliy
+ * @since 07/01/2018.
+ */
+
+public interface LoggingContextService {
+
+    /**
+     * Allows to store a key-value pair on thread context
+     */
+    void put(String key, String value);
+
+    /**
+     * Returns the value associated with a key stored on thread context
+     *
+     * @return value or <code>null</code> if the key does not exits
+     */
+    String get(String key);
+
+    /**
+     * Removes a particular key from thread context
+     */
+    void remove(String key);
+
+    /**
+     * Clear logging thread context
+     */
+    void clear();
+
+    /**
+     * Copies logging context of current thread onto a {@link Runnable}, so that the context is available
+     * when this {@link Runnable} runs in another thread.
+     */
+    Runnable toRunnable(Runnable runnable);
+
+    /**
+     * Copies logging context of current thread onto a {@link Callable}, so that the context is available
+     * when this {@link Callable} runs in another thread
+     */
+    <V> Callable<V> toCallable(Callable<V> callable);
+}
diff --git a/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/provider/LoggingServiceProvider.java b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/provider/LoggingServiceProvider.java
new file mode 100644
index 0000000000..baf99f0e55
--- /dev/null
+++ b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/provider/LoggingServiceProvider.java
@@ -0,0 +1,30 @@
+/*
+ * Copyright © 2016-2017 European Support Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.openecomp.sdc.logging.provider;
+
+/**
+ * <p>From the application code (consumer) perspective, logger creation (factory) and logging context are independent
+ * services. From the service provider perspective, however, these services are related and must be implemented together
+ * using the same underlying mechanism. Therefore, the service provider-facing interface combines the two services
+ * &mdash; to eliminate the chance that their implementations don't work well together.</p>
+ *
+ * @author EVITALIY
+ * @since 07 Jan 18
+ */
+public interface LoggingServiceProvider extends LoggerCreationService, LoggingContextService {
+    // single provider must implement two separate consumer services
+}
diff --git a/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/test/java/org/openecomp/sdc/logging/api/LoggerFactoryTest.java b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/test/java/org/openecomp/sdc/logging/api/LoggerFactoryTest.java
index 4b3a1ba7c7..9fde4e5e6c 100644
--- a/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/test/java/org/openecomp/sdc/logging/api/LoggerFactoryTest.java
+++ b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/test/java/org/openecomp/sdc/logging/api/LoggerFactoryTest.java
@@ -4,9 +4,9 @@
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- * 
+ *
  *      http://www.apache.org/licenses/LICENSE-2.0
- * 
+ *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -19,10 +19,8 @@ package org.openecomp.sdc.logging.api;
 import org.testng.annotations.Test;
 
 import java.lang.reflect.Field;
-import java.util.ServiceLoader;
 
 import static org.testng.Assert.assertEquals;
-import static org.testng.Assert.assertFalse;
 import static org.testng.Assert.assertNotNull;
 
 /**
@@ -31,40 +29,48 @@ import static org.testng.Assert.assertNotNull;
  */
 public class LoggerFactoryTest {
 
-  @Test
-  public void testNoOpLoggerService() throws Exception {
+    @Test
+    public void shouldHoldNoOpWhenNoBinding() throws Exception {
+
+        // set up to access the private static field
+        Field factory = LoggerFactory.class.getDeclaredField("SERVICE");
+        factory.setAccessible(true);
+        Object impl = factory.get(null);
 
-    assertFalse(ServiceLoader.load(LoggerCreationService.class).iterator().hasNext());
+        assertEquals(impl.getClass().getName(),
+                "org.openecomp.sdc.logging.api.LoggerFactory$NoOpLoggerCreationService");
+    }
 
-    LoggerFactory.getLogger(LoggerFactoryTest.class);
-    Field factory = LoggerFactory.class.getDeclaredField("SERVICE");
-    factory.setAccessible(true);
-    Object impl = factory.get(null);
-    assertEquals("org.openecomp.sdc.logging.api.LoggerFactory$NoOpLoggerCreationService",
-        impl.getClass().getName());
-  }
+    @Test
+    public void verifyNoOpLoggerWorksWhenGotByClass() {
+        Logger logger = LoggerFactory.getLogger(LoggerFactoryTest.class);
+        verifyLoggerWorks(logger);
+    }
 
-  @Test
-  public void testNoOpLoggerByClass() throws Exception {
-    Logger logger = LoggerFactory.getLogger(LoggerFactoryTest.class);
-    verifyLogger(logger);
-  }
+    @Test
+    public void verifyNoOpLoggerWorksWhenGotByName() {
+        Logger logger = LoggerFactory.getLogger(LoggerFactoryTest.class.getName());
+        verifyLoggerWorks(logger);
+    }
 
-  @Test
-  public void testNoOpLoggerByName() throws Exception {
-    Logger logger = LoggerFactory.getLogger(LoggerFactoryTest.class.getName());
-    verifyLogger(logger);
-  }
+    @Test(expectedExceptions = NullPointerException.class)
+    public void throwNpeWhenGetByNameWithNull() {
+        LoggerFactory.getLogger((String) null);
+    }
 
-  private void verifyLogger(Logger logger) {
-    assertNotNull(logger);
+    @Test(expectedExceptions = NullPointerException.class)
+    public void throwNpeWhenGetByClassWithNull() {
+        LoggerFactory.getLogger((Class<LoggerFactoryTest>) null);
+    }
 
-    // make sure no exceptions are thrown
-    logger.error("");
-    logger.warn("");
-    logger.info("");
-    logger.debug("");
-    logger.audit("");
-    logger.metrics("");
-  }
+    private void verifyLoggerWorks(Logger logger) {
+        assertNotNull(logger);
+        // make sure no exceptions are thrown
+        logger.error("");
+        logger.warn("");
+        logger.info("");
+        logger.debug("");
+        logger.audit("");
+        logger.metrics("");
+    }
 }
diff --git a/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/test/java/org/openecomp/sdc/logging/api/LoggingContextTest.java b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/test/java/org/openecomp/sdc/logging/api/LoggingContextTest.java
new file mode 100644
index 0000000000..7899eebd51
--- /dev/null
+++ b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/test/java/org/openecomp/sdc/logging/api/LoggingContextTest.java
@@ -0,0 +1,101 @@
+/*
+ * Copyright © 2016-2017 European Support Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.openecomp.sdc.logging.api;
+
+import org.testng.annotations.Test;
+
+import java.lang.reflect.Field;
+import java.util.concurrent.Callable;
+
+import static org.testng.Assert.assertEquals;
+import static org.testng.Assert.assertNull;
+import static org.testng.Assert.assertTrue;
+
+/**
+ * @author EVITALIY
+ * @since 08 Jan 18
+ */
+public class LoggingContextTest {
+
+    @Test
+    public void shouldHoldNoOpWhenNoBinding() throws Exception {
+        Field factory = LoggingContext.class.getDeclaredField("SERVICE");
+        factory.setAccessible(true);
+        Object impl = factory.get(null);
+        assertEquals(impl.getClass().getName(),
+                "org.openecomp.sdc.logging.api.LoggingContext$NoOpLoggingContextService");
+    }
+
+    @Test
+    public void putDoesNotHaveEffectWhenNoBinding() {
+        final String key = "Key";
+        LoggingContext.put(key, "Dummy");
+        assertNull(LoggingContext.get(key));
+    }
+
+    @Test(expectedExceptions = NullPointerException.class)
+    public void throwNpeWhenPutWithKeyNull() {
+        LoggingContext.put(null, "value");
+    }
+
+    @Test
+    public void getAlwaysReturnsNull() {
+        assertNull(LoggingContext.get("GetKey"));
+    }
+
+    @Test(expectedExceptions = NullPointerException.class)
+    public void throwNpeWhenGetWithKeyNull() {
+        LoggingContext.get(null);
+    }
+
+    @Test
+    public void removeDoesNotFail() {
+        LoggingContext.remove("RemoveKey");
+    }
+
+    @Test(expectedExceptions = NullPointerException.class)
+    public void throwNpWhenRemoveWithKeyNull() {
+        LoggingContext.remove(null);
+    }
+
+    @Test
+    public void clearDoesNotFail() {
+        LoggingContext.clear();
+    }
+
+    @Test
+    public void toRunnableReturnsSameInstance() {
+        Runnable test = () -> { /* do nothing */ };
+        assertTrue(test == LoggingContext.toRunnable(test));
+    }
+
+    @Test(expectedExceptions = NullPointerException.class)
+    public void throwNpeWhenToRunnableWithNull() {
+        LoggingContext.toRunnable(null);
+    }
+
+    @Test
+    public void toCallableReturnsSameInstance() {
+        Callable<String> test = () -> "";
+        assertTrue(test == LoggingContext.toCallable(test));
+    }
+
+    @Test(expectedExceptions = NullPointerException.class)
+    public void throwNpeWhenToCallableWithNull() {
+        LoggingContext.toCallable(null);
+    }
+}
\ No newline at end of file
diff --git a/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/context/ContextPropagationService.java b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/test/java/org/openecomp/sdc/logging/api/ServiceBinderTest.java
index 7207ea7610..1a5c81d90d 100644
--- a/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/context/ContextPropagationService.java
+++ b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/test/java/org/openecomp/sdc/logging/api/ServiceBinderTest.java
@@ -4,9 +4,9 @@
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- * 
+ *
  *      http://www.apache.org/licenses/LICENSE-2.0
- * 
+ *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -14,17 +14,25 @@
  * limitations under the License.
  */
 
-package org.openecomp.sdc.logging.api.context;
+package org.openecomp.sdc.logging.api;
+
+import org.testng.annotations.Test;
+
+import static org.testng.Assert.*;
 
 /**
- * Should be used to implement a framework-specific mechanism of propagation of a diagnostic context to child threads.
- *
- * @author evitaliy
- * @since 12/09/2016.
+ * @author EVITALIY
+ * @since 08 Jan 18
  */
+public class ServiceBinderTest {
 
-@FunctionalInterface
-public interface ContextPropagationService {
+    @Test
+    public void makeSureNoContextServiceBinding() {
+        assertFalse(ServiceBinder.getContextServiceBinding().isPresent());
+    }
 
-    Runnable create(Runnable task);
-}
+    @Test
+    public void makeSureNoCreationServiceBinding() {
+        assertFalse(ServiceBinder.getCreationServiceBinding().isPresent());
+    }
+}
\ No newline at end of file
diff --git a/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/test/java/org/openecomp/sdc/logging/api/context/TaskFactoryTest.java b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/test/java/org/openecomp/sdc/logging/api/context/TaskFactoryTest.java
deleted file mode 100644
index f5c2187024..0000000000
--- a/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/test/java/org/openecomp/sdc/logging/api/context/TaskFactoryTest.java
+++ /dev/null
@@ -1,32 +0,0 @@
-package org.openecomp.sdc.logging.api.context;
-
-import org.testng.annotations.Test;
-
-import java.util.ServiceLoader;
-
-import static org.testng.Assert.assertFalse;
-import static org.testng.Assert.assertNotNull;
-import static org.testng.Assert.assertTrue;
-
-/**
- * @author evitaliy
- * @since 14/09/2016.
- */
-public class TaskFactoryTest {
-
-  @Test(expectedExceptions = RuntimeException.class)
-  public void testNoImplementation() throws Exception {
-
-    assertFalse(ServiceLoader.load(ContextPropagationService.class).iterator().hasNext());
-
-    try {
-      TaskFactory.create(() -> {
-      });
-    } catch (RuntimeException e) {
-      Throwable cause = e.getCause();
-      assertNotNull(cause);
-      assertTrue(cause.getMessage().contains(ContextPropagationService.class.getName()));
-      throw e;
-    }
-  }
-}
\ No newline at end of file