Allow App To Choose Between MsgResponse Sinks

- MZS Schema Change: Add "MsgResponseSinks" element to
  mzs:DeliveryRequest/Config that allows sender to configure how
  MsgResponses should be archived.
- ConfigUtil: Interpret MsgResponseSink parameters from Spring
  Environment and merge with ConfigType.
- MsgResponseBackend: Send responses to sinks according to
  MsgResponseSinks in Config
- application.yaml: Add MsgResponseSinks parameter to configuration.
- Uncouple Sink implementations from java.util.function.Function,
  because the sink interfaces are going to differ and there is no need
  to unite them under one interface.
- Add and test LogResponseSink, which logs responses to it's logger.
- MsgResponse: Add JAXB getter for response. Reason: Can be passed to
  marshaller.

11 files changed, 286 insertions, 49 deletions

diff --git a/src/main/java/at/gv/egiz/moazs/backend/LogResponseSink.java b/src/main/java/at/gv/egiz/moazs/backend/LogResponseSink.java
new file mode 100644
index 0000000..d419944
--- /dev/null
+++ b/src/main/java/at/gv/egiz/moazs/backend/LogResponseSink.java
@@ -0,0 +1,44 @@
+package at.gv.egiz.moazs.backend;
+
+import at.gv.egiz.moazs.scheme.Marshaller;
+import at.gv.egiz.moazs.scheme.MsgResponse;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.stereotype.Component;
+
+import java.util.concurrent.CompletableFuture;
+
+import static java.util.concurrent.CompletableFuture.completedFuture;
+
+@Component
+public class LogResponseSink {
+
+    private static final Logger log = LoggerFactory.getLogger(LogResponseSink.class);
+    private static final String LOG_LEVEL_WARN_MESSAGE = "Will not log response because INFO level is disabled.";
+
+    private final Marshaller msgMarshaller;
+
+    public LogResponseSink(Marshaller msgMarshaller) {
+        this.msgMarshaller = msgMarshaller;
+    }
+
+    /**
+     * Log response to class logger at level=INFO.
+     *
+     * @param msgResponse
+     * @return
+     */
+    public CompletableFuture<Void> log(MsgResponse msgResponse) {
+
+        if(log.isInfoEnabled()) {
+            var builder = new StringBuilder("Received the following Message: \n");
+            builder.append(msgMarshaller.marshallXml(msgResponse.getResponseAsJAXBElement()));
+            log.info(builder.toString());
+        } else {
+            log.warn(LOG_LEVEL_WARN_MESSAGE);
+        }
+
+        return completedFuture(null);
+
+    }
+}
diff --git a/src/main/java/at/gv/egiz/moazs/backend/MsgResponseBackend.java b/src/main/java/at/gv/egiz/moazs/backend/MsgResponseBackend.java
index 414c2dc..1b17f34 100644
--- a/src/main/java/at/gv/egiz/moazs/backend/MsgResponseBackend.java
+++ b/src/main/java/at/gv/egiz/moazs/backend/MsgResponseBackend.java
@@ -4,14 +4,13 @@ import at.gv.egiz.moazs.MoaZSException;
 import at.gv.egiz.moazs.repository.DeliveryRepository;
 import at.gv.egiz.moazs.scheme.MsgResponse;
 import at.gv.egiz.moazs.service.MsgService;
+import at.gv.zustellung.app2mzs.xsd.MsgResponseSinksType;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Component;
 
-import java.util.concurrent.CompletableFuture;
 import java.util.function.Consumer;
-import java.util.function.Function;
 
 import static at.gv.egiz.moazs.MoaZSException.moaZSExceptionBuilder;
 import static java.lang.String.format;
@@ -27,29 +26,38 @@ public class MsgResponseBackend implements Consumer<String> {
 
     private final DeliveryRepository repository;
     private final Consumer<byte[]> signatureVerifier;
-    private final Function<MsgResponse, CompletableFuture<Void>> sink;
+    private final SaveResponseToFileSink saveResponseToFileSink;
+    private final LogResponseSink logResponseSink;
 
     @Autowired
     public MsgResponseBackend(DeliveryRepository repository,
                               Consumer<byte[]> signatureVerifier,
-                              Function<MsgResponse, CompletableFuture<Void>> sink) {
+                              SaveResponseToFileSink saveResponseToFileSink,
+                              LogResponseSink logResponseSink) {
         this.repository = repository;
         this.signatureVerifier = signatureVerifier;
-        this.sink = sink;
+        this.saveResponseToFileSink = saveResponseToFileSink;
+        this.logResponseSink = logResponseSink;
     }
 
     /**
      * Performs all {@code MsgResponse}'s Back-End Tasks, such as verifying
      * its signature and archiving the response.
      *
+     * Note: When the signature verification fails, this method will not archive
+     * the original response (the one that was received from msg) to the sink,
+     * but an error message.
+     *
      * @param responseID refers to MsgResponse Object.
      */
     @Override
     public void accept(String responseID) {
-        supplyAsync(() -> verify(responseID)).thenAcceptAsync(sink::apply);
+
+        supplyAsync(() -> verify(responseID))
+                .thenAcceptAsync(msgResponse -> applySinks(msgResponse));
     }
 
-    public MsgResponse verify(String responseID) {
+    private MsgResponse verify(String responseID) {
 
         var response = repository.retrieveResponse(responseID).get();
         var builder = moaZSExceptionBuilder().withAllParametersInAnswer(response.getAnswer());
@@ -72,4 +80,23 @@ public class MsgResponseBackend implements Consumer<String> {
 
     }
 
+    private void applySinks(MsgResponse msgResponse) {
+
+        var sinkParams = getSinkParams(msgResponse);
+
+        if (sinkParams.isSafeResponseToFile()) {
+            supplyAsync(() -> saveResponseToFileSink.save(msgResponse));
+        }
+
+        if (sinkParams.isLogResponse()) {
+            supplyAsync(() -> logResponseSink.log(msgResponse));
+        }
+    }
+
+    private MsgResponseSinksType getSinkParams(MsgResponse msgResponse) {
+        var appDeliveryID = msgResponse.getAppDeliveryID();
+        var request = repository.retrieveDeliveryRequest(appDeliveryID).get();
+        return request.getConfig().getMsgResponseSinks();
+    }
+
 }
diff --git a/src/main/java/at/gv/egiz/moazs/backend/SaveResponseToFileSink.java b/src/main/java/at/gv/egiz/moazs/backend/SaveResponseToFileSink.java
index 02771a9..7da76ef 100644
--- a/src/main/java/at/gv/egiz/moazs/backend/SaveResponseToFileSink.java
+++ b/src/main/java/at/gv/egiz/moazs/backend/SaveResponseToFileSink.java
@@ -15,7 +15,6 @@ import java.nio.charset.StandardCharsets;
 import java.text.SimpleDateFormat;
 import java.util.Date;
 import java.util.concurrent.CompletableFuture;
-import java.util.function.Function;
 
 import static at.gv.egiz.moazs.MoaZSException.moaZSException;
 import static java.lang.String.format;
@@ -23,10 +22,11 @@ import static java.util.concurrent.CompletableFuture.allOf;
 import static java.util.concurrent.CompletableFuture.supplyAsync;
 
 @Component
-public class SaveResponseToFileSink implements Function<MsgResponse, CompletableFuture<Void>> {
+public class SaveResponseToFileSink {
 
     private static final Logger log = LoggerFactory.getLogger(SaveResponseToFileSink.class);
     private static final String SAVING_FAILED_MSG = "Could not save response with AppDeliveryId=%s.";
+    private static final String SAVE_RESPONSE_MSG = "Saving response to {}..." ;
 
     private final SimpleDateFormat isoFormatter;
     private final Marshaller msgMarshaller;
@@ -41,8 +41,13 @@ public class SaveResponseToFileSink implements Function<MsgResponse, Completable
         this.isoFormatter = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
     }
 
-    @Override
-    public CompletableFuture<Void> apply(MsgResponse response) {
+    /**
+     * Save response and it's binary version to the file system.
+     *
+     * @param response
+     * @return Future that completes when both responses have been written to the file system.
+     */
+    public CompletableFuture<Void> save(MsgResponse response) {
 
         var responseID = response.getResponseID();
 
@@ -79,6 +84,7 @@ public class SaveResponseToFileSink implements Function<MsgResponse, Completable
     }
 
     private void storeToFile(String path, byte[] content) {
+        log.trace(SAVE_RESPONSE_MSG, path);
         try {
             FileUtils.writeByteArrayToFile(new File(path), content);
         } catch (IOException e) {
diff --git a/src/main/java/at/gv/egiz/moazs/preprocess/ConfigUtil.java b/src/main/java/at/gv/egiz/moazs/preprocess/ConfigUtil.java
index 68f833e..9cdc07a 100644
--- a/src/main/java/at/gv/egiz/moazs/preprocess/ConfigUtil.java
+++ b/src/main/java/at/gv/egiz/moazs/preprocess/ConfigUtil.java
@@ -1,10 +1,7 @@
 package at.gv.egiz.moazs.preprocess;
 
 import at.gv.egiz.moazs.util.StringUtils;
-import at.gv.zustellung.app2mzs.xsd.ClientType;
-import at.gv.zustellung.app2mzs.xsd.ConfigType;
-import at.gv.zustellung.app2mzs.xsd.KeyStoreType;
-import at.gv.zustellung.app2mzs.xsd.SSLType;
+import at.gv.zustellung.app2mzs.xsd.*;
 import org.springframework.stereotype.Component;
 
 import java.math.BigInteger;
@@ -13,6 +10,7 @@ import java.util.Map;
 import static at.gv.zustellung.app2mzs.xsd.ClientType.clientTypeBuilder;
 import static at.gv.zustellung.app2mzs.xsd.ConfigType.configTypeBuilder;
 import static at.gv.zustellung.app2mzs.xsd.KeyStoreType.keyStoreTypeBuilder;
+import static at.gv.zustellung.app2mzs.xsd.MsgResponseSinksType.msgResponseSinksTypeBuilder;
 import static at.gv.zustellung.app2mzs.xsd.SSLType.SSLTypeBuilder;
 import static java.util.stream.Collectors.toMap;
 
@@ -33,7 +31,9 @@ public class ConfigUtil {
     public static final String PASSWORD_KEY = "password";
     public static final String RECEIVE_TIMEOUT = "receive-timeout";
     public static final String CONNECTION_TIMEOUT_KEY = "connection-timeout";
-
+    public static final String MSG_RESPONSE_SINKS_KEY = "msg-response-sinks";
+    public static final String LOG_RESPONSE_KEY = "log-response";
+    public static final String SAVE_RESPONSE_TO_FILE_KEY = "save-response-to-file";
 
     /**
      * Convert a map into a Config object.
@@ -53,10 +53,15 @@ public class ConfigUtil {
         ClientType tnvzClient = tnvzClientParams.isEmpty()
                 ? null : buildClient(tnvzClientParams);
 
+        var msgResponseSinksParams = filterMapByPrefix(values, MSG_RESPONSE_SINKS_KEY);
+        MsgResponseSinksType sinks = msgResponseSinksParams.isEmpty()
+                ? null : buildMsgResponseSinks(msgResponseSinksParams);
+
         return ConfigType.configTypeBuilder()
                 .withPerformQueryPersonRequest(performQueryPersonRequest)
                 .withMSGClient(msgClient)
                 .withTNVZClient(tnvzClient)
+                .withMsgResponseSinks(sinks)
                 .build();
     }
 
@@ -102,11 +107,8 @@ public class ConfigUtil {
         KeyStoreType trustStore = trustStoreParams.isEmpty()
                 ? null : buildKeyStore(trustStoreParams);
 
-        var trustAll = sslParams.get(TRUST_ALL_KEY) == null
-                ? null : Boolean.getBoolean(sslParams.get(TRUST_ALL_KEY));
-
-        var laxHostNameVerification = sslParams.get(LAX_HOSTNAME_VERIFICATION_KEY) == null
-                ? null : Boolean.getBoolean(sslParams.get(LAX_HOSTNAME_VERIFICATION_KEY));
+        var trustAll = booleanOrNull(sslParams.get(TRUST_ALL_KEY));
+        var laxHostNameVerification = booleanOrNull(sslParams.get(LAX_HOSTNAME_VERIFICATION_KEY));
 
         return SSLTypeBuilder()
                 .withKeyStore(keyStore)
@@ -126,6 +128,22 @@ public class ConfigUtil {
                 .build();
     }
 
+    private MsgResponseSinksType buildMsgResponseSinks(Map<String, String> params) {
+
+        var logResponse  = booleanOrNull(params.get(LOG_RESPONSE_KEY));
+        var saveResponse = booleanOrNull(params.get(SAVE_RESPONSE_TO_FILE_KEY));
+
+        return msgResponseSinksTypeBuilder()
+                .withLogResponse(logResponse)
+                .withLogResponse(saveResponse)
+                .build();
+    }
+
+    private Boolean booleanOrNull(String value) {
+        return value == null ? null : Boolean.getBoolean(value);
+    }
+
+
     /**
      * Combine properties of two Configs; {@code primary} overrides {@code fallback}.
      *
@@ -149,6 +167,10 @@ public class ConfigUtil {
             builder.withMSGClient(merge(primary.getTNVZClient(), fallback.getTNVZClient()));
         }
 
+        if (primary.getMsgResponseSinks() != null) {
+            builder.withMsgResponseSinks(merge(primary.getMsgResponseSinks(), fallback.getMsgResponseSinks()));
+        }
+
         return builder.build();
     }
 
@@ -214,4 +236,24 @@ public class ConfigUtil {
 
     }
 
+    private MsgResponseSinksType merge(MsgResponseSinksType primary, MsgResponseSinksType fallback) {
+
+        if (fallback == null) {
+            return primary;
+        }
+
+        var builder = msgResponseSinksTypeBuilder(fallback);
+
+        if (primary.isLogResponse() != null)  {
+            builder.withLogResponse(primary.isLogResponse());
+        }
+
+        if (primary.isSafeResponseToFile() != null)  {
+            builder.withLogResponse(primary.isSafeResponseToFile());
+        }
+
+        return builder.build();
+    }
+
+
 }
diff --git a/src/main/java/at/gv/egiz/moazs/scheme/MsgResponse.java b/src/main/java/at/gv/egiz/moazs/scheme/MsgResponse.java
index 80e2059..5370448 100644
--- a/src/main/java/at/gv/egiz/moazs/scheme/MsgResponse.java
+++ b/src/main/java/at/gv/egiz/moazs/scheme/MsgResponse.java
@@ -3,6 +3,12 @@ package at.gv.egiz.moazs.scheme;
 import at.gv.egiz.moazs.MoaZSException;
 import at.gv.zustellung.msg.xsd.DeliveryAnswerType;
 
+import javax.xml.bind.JAXBElement;
+
+/**
+ * Represents responses to DeliveryRequests that were received from the msg service.
+ * @param <T> The type of the response.
+ */
 public abstract class MsgResponse <T> {
 
     protected String id;
@@ -20,6 +26,7 @@ public abstract class MsgResponse <T> {
     }
 
     public abstract T getResponse();
+    public abstract JAXBElement<T> getResponseAsJAXBElement();
     public abstract String getAppDeliveryID();
     public abstract String getZSDeliveryID();
     public abstract DeliveryAnswerType getAnswer();
diff --git a/src/main/java/at/gv/egiz/moazs/scheme/NotificationResponse.java b/src/main/java/at/gv/egiz/moazs/scheme/NotificationResponse.java
index de1fd38..784d000 100644
--- a/src/main/java/at/gv/egiz/moazs/scheme/NotificationResponse.java
+++ b/src/main/java/at/gv/egiz/moazs/scheme/NotificationResponse.java
@@ -3,6 +3,9 @@ package at.gv.egiz.moazs.scheme;
 import at.gv.egiz.moazs.MoaZSException;
 import at.gv.zustellung.msg.xsd.DeliveryAnswerType;
 import at.gv.zustellung.msg.xsd.DeliveryNotificationType;
+import at.gv.zustellung.msg.xsd.ObjectFactory;
+
+import javax.xml.bind.JAXBElement;
 
 import static at.gv.zustellung.msg.xsd.DeliveryNotificationType.deliveryNotificationTypeBuilder;
 
@@ -10,6 +13,7 @@ public class NotificationResponse extends MsgResponse<DeliveryNotificationType>
 
     private final DeliveryNotificationType notification;
     private static final String ID_SUFFIX = ".NO";
+    private static final ObjectFactory factory = new ObjectFactory();
 
     public NotificationResponse(DeliveryNotificationType notification) {
         super.id = createResponseId(notification.getAppDeliveryID(), ID_SUFFIX);
@@ -26,6 +30,11 @@ public class NotificationResponse extends MsgResponse<DeliveryNotificationType>
     }
 
     @Override
+    public JAXBElement<DeliveryNotificationType> getResponseAsJAXBElement() {
+        return factory.createDeliveryNotification(notification);
+    }
+
+    @Override
     public String getAppDeliveryID() {
         return notification.getAppDeliveryID();
     }
diff --git a/src/main/java/at/gv/egiz/moazs/scheme/RequestStatusResponse.java b/src/main/java/at/gv/egiz/moazs/scheme/RequestStatusResponse.java
index 0705698..3b4710b 100644
--- a/src/main/java/at/gv/egiz/moazs/scheme/RequestStatusResponse.java
+++ b/src/main/java/at/gv/egiz/moazs/scheme/RequestStatusResponse.java
@@ -4,6 +4,9 @@ import at.gv.egiz.moazs.MoaZSException;
 import at.gv.zustellung.msg.xsd.DeliveryAnswerType;
 import at.gv.zustellung.msg.xsd.DeliveryRequestStatusType;
 import at.gv.zustellung.msg.xsd.ErrorInfoType;
+import at.gv.zustellung.msg.xsd.ObjectFactory;
+
+import javax.xml.bind.JAXBElement;
 
 import static at.gv.egiz.moazs.util.NullCoalesce.coalesce;
 import static at.gv.zustellung.msg.xsd.DeliveryRequestStatusType.Error.errorBuilder;
@@ -15,6 +18,8 @@ public class RequestStatusResponse extends MsgResponse<DeliveryRequestStatusType
     private final DeliveryRequestStatusType status;
     private final DeliveryAnswerType answer;
     private static final String ID_SUFFIX = ".RS";
+    private static final ObjectFactory factory = new ObjectFactory();
+
 
     public RequestStatusResponse(DeliveryRequestStatusType status) {
         this.status = status;
@@ -32,6 +37,11 @@ public class RequestStatusResponse extends MsgResponse<DeliveryRequestStatusType
     }
 
     @Override
+    public JAXBElement<DeliveryRequestStatusType> getResponseAsJAXBElement() {
+        return factory.createDeliveryRequestStatus(status);
+    }
+
+    @Override
     public String getAppDeliveryID() {
         return answer.getAppDeliveryID();
     }
diff --git a/src/main/resources/application.yaml b/src/main/resources/application.yaml
index 0e7b67e..a04a903 100644
--- a/src/main/resources/application.yaml
+++ b/src/main/resources/application.yaml
@@ -1,11 +1,18 @@
-spring:
-  redis:
-    host: 172.17.0.2
-    port: 6379
+### Logging
+logging:
+  level:
+    root: WARN
+    org.springframework: WARN
+    at.gv: INFO #DEBUG
+    iaik: INFO #DEBUG
+    at.gv.egiz.moazs.backend:
+      SignatureVerifier: DEBUG
+      LogResponseSink: INFO
 
-## activate cluster mode
-#  profiles:
-#    active: cluster
+# Default type for java's ssl key/trust store
+javax.net.ssl:
+  keyStoreType: jks
+  trustStoreType: jks
 
 # Configure parameters here or in DeliveryRequest/Config.
 # Choose a profile in DeliveryRequest/Config/ProfileId.
@@ -23,8 +30,12 @@ delivery-request-configuration-profiles:
       # 0 means indefinitely.
       receive-timeout: 0
 
+    # Specifies how MoaZS should
+    msg-response-sinks:
+      save-response-to-file: false
+      log-response: true
+
   ssl-profile:
-    perform-query-person-request: false
     msg-client:
       url: https://localhost/zusemsg/services/DeliveryRequest
       ssl:
@@ -43,24 +54,10 @@ delivery-request-configuration-profiles:
           ## JKS or PKCS12
           type: PKCS12
 
-## If set to false, moa zs ignores an incomplete default DeliveryRequest-configuration
-## profile and continues startup. See 'delivery-request-configuration-profiles'.
-## Default value: true
-# verify-completeness-of-default-delivery-request-configuration: false
-
-### logging
-logging:
-  level:
-    root: WARN
-    org.springframework: WARN
-    at.gv: INFO #DEBUG
-    iaik: INFO #DEBUG
-    at.gv.egiz.moazs.backend.SignatureVerifier: DEBUG
-
-# default type for java's ssl key/trust store
-javax.net.ssl:
-  keyStoreType: jks
-  trustStoreType: jks
+# If set to false, moa zs ignores an incomplete default DeliveryRequest-configuration
+# profile and continues startup. See 'delivery-request-configuration-profiles'.
+# Default value: true
+verify-completeness-of-default-delivery-request-configuration: true
 
 ### moa spss config
 moa.spss:
@@ -74,6 +71,15 @@ moa.spss:
     configuration: moa-spss/MOASPSSConfiguration.xml
     default-trustprofile: test-trustprofile
 
+spring:
+  redis:
+    host: 172.17.0.2
+    port: 6379
+
 repository:
   # duration in minutes before repository records are evicted.
-  expiresAfterWrite: 30
\ No newline at end of file
+  expiresAfterWrite: 30
+
+## activate cluster mode
+#  profiles:
+#    active: cluster
diff --git a/src/main/resources/mzs/app2mzs.xsd b/src/main/resources/mzs/app2mzs.xsd
index 659bbb9..ba99eab 100644
--- a/src/main/resources/mzs/app2mzs.xsd
+++ b/src/main/resources/mzs/app2mzs.xsd
@@ -98,6 +98,7 @@
 			<xs:element name="PerformQueryPersonRequest" type="xs:boolean" minOccurs="0" />
 			<xs:element ref="MSGClient" minOccurs="0" />
 			<xs:element ref="TNVZClient" minOccurs="0" />
+			<xs:element ref="MsgResponseSinks" minOccurs="0" />
 		</xs:sequence>
 	</xs:complexType>
 	<xs:element name="MSGClient" type="ClientType" />
@@ -128,6 +129,13 @@
 			<xs:element name="FileType" type="xs:string" minOccurs="0"/>
 		</xs:sequence>
 	</xs:complexType>
+	<xs:element name="MsgResponseSinks" type="MsgResponseSinksType"/>
+	<xs:complexType name="MsgResponseSinksType">
+		<xs:sequence>
+			<xs:element name="SafeResponseToFile" type="xs:boolean" minOccurs="0" />
+			<xs:element name="LogResponse" type="xs:boolean" minOccurs="0" />
+		</xs:sequence>
+	</xs:complexType>
 	<xs:element name="DeliveryResponse" type="DeliveryResponseType"/>
 	<xs:complexType name="DeliveryResponseType">
 		<xs:choice>
diff --git a/src/test/java/at/gv/egiz/moazs/LogResponseSinkTest.java b/src/test/java/at/gv/egiz/moazs/LogResponseSinkTest.java
new file mode 100644
index 0000000..9e7c49d
--- /dev/null
+++ b/src/test/java/at/gv/egiz/moazs/LogResponseSinkTest.java
@@ -0,0 +1,78 @@
+package at.gv.egiz.moazs;
+
+import at.gv.egiz.moazs.backend.LogResponseSink;
+import at.gv.egiz.moazs.scheme.Marshaller;
+import at.gv.egiz.moazs.scheme.NotificationResponse;
+import ch.qos.logback.classic.Level;
+import ch.qos.logback.classic.spi.ILoggingEvent;
+import ch.qos.logback.core.Appender;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnitRunner;
+import org.slf4j.LoggerFactory;
+
+import static at.gv.zustellung.msg.xsd.DeliveryNotificationType.deliveryNotificationTypeBuilder;
+import static org.mockito.ArgumentMatchers.argThat;
+import static org.mockito.Mockito.verify;
+
+@RunWith(MockitoJUnitRunner.class)
+public class LogResponseSinkTest {
+
+    private LogResponseSink logResponseSink;
+
+    @Mock
+    private Appender appender;
+    private ch.qos.logback.classic.Logger logger;
+
+    @Before
+    public void setup() {
+        logResponseSink = new LogResponseSink(new Marshaller(false));
+        logger = (ch.qos.logback.classic.Logger) LoggerFactory.getLogger(LogResponseSink.class);
+        logger.addAppender(appender);
+    }
+
+    @Test
+    public void logNotification() {
+        setLogLevel(Level.INFO);
+        var appDeliveryID = "log-notification-id";
+        var notification = setupNotification(appDeliveryID);
+
+        logResponseSink.log(notification)
+                .thenRun(expectSubstringSentToAppender(appDeliveryID));
+    }
+
+    @Test
+    public void warnWhenLogDisabled() {
+        setLogLevel(Level.WARN);
+        var appDeliveryID = "log-info-disabled";
+        var notification = setupNotification(appDeliveryID);
+
+        logResponseSink.log(notification)
+                .thenRun(expectSubstringSentToAppender("WARN"));
+    }
+
+    private Runnable expectSubstringSentToAppender(String expectedSubstring) {
+        return ()-> verify(appender).doAppend(argThat(argument -> {
+            var message = ((ILoggingEvent) argument).getFormattedMessage();
+            return message.contains(expectedSubstring);
+        }));
+    }
+
+    private NotificationResponse setupNotification(String appDeliveryID) {
+
+        var notification = deliveryNotificationTypeBuilder()
+                .withAppDeliveryID(appDeliveryID)
+                .build();
+
+        return new NotificationResponse(notification);
+
+    }
+
+    private void setLogLevel(Level level) {
+        logger.setLevel(level);
+    }
+
+
+}
diff --git a/src/test/java/at/gv/egiz/moazs/SaveResponseToFileSinkTest.java b/src/test/java/at/gv/egiz/moazs/SaveResponseToFileSinkTest.java
index 9ddd37e..58efe6a 100644
--- a/src/test/java/at/gv/egiz/moazs/SaveResponseToFileSinkTest.java
+++ b/src/test/java/at/gv/egiz/moazs/SaveResponseToFileSinkTest.java
@@ -63,7 +63,7 @@ public class SaveResponseToFileSinkTest {
         var fileContent = "<xml>some content</xml>";
         var status = setupMocks(fileContent);
 
-        sink.apply(status)
+        sink.save(status)
                 .thenRun(() -> assertFilesCreatedAndContentMatches(fileContent));
     }