feat(logging/logback): update docs, align logback with log4j implementation

Author: cmtjk

docs/core/logging.md

@@ -378,9 +378,17 @@ You can use Powertools for AWS Lambda Logging with either the `@Logging` annotat
     }
     ```
 
-???+ warning "SLF4J Fluent Logging API"
-    When using [SLF4J Fluent Logging API](https://www.slf4j.org/manual.html#fluent) **do not add reserved keys** listed in [standard structured keys](#standard-structured-keys) and [additional structured keys](#additional-structured-keys) as key-value pairs via `addKeyValue`.
-    This may cause unindented behavior.
+???+ warning "Do not reuse reserved keys"
+
+    Do not reuse reserved keys listed in [standard structured keys](#standard-structured-keys) and [additional structured keys](#additional-structured-keys).
+    This restriction applies to all structured logging mechanisms, including:
+
+    - Log arguments
+    - MDC entries
+    - `addKeyValue(...)` or `addArgument(...)` of [SLF4J Fluent Logging API](https://www.slf4j.org/manual.html#fluent)
+    - Any other structured data fields
+
+    Reusing reserved keys in any of these contexts may result in unintended or inconsistent behavior.
 
 ## Standard structured keys
 

powertools-logging/powertools-logging-logback/src/main/java/software/amazon/lambda/powertools/logging/logback/JsonUtils.java

@@ -73,12 +73,6 @@ static void serializeMDCEntry(Map.Entry<String, String> entry, JsonSerializer se
         }
     }
 
-    static void serializeKVPEntry(String key, Object value, JsonSerializer serializer) {
-        serializer.writeRaw(',');
-        serializer.writeFieldName(key);
-        serializer.writeObject(value);
-    }
-
     static void serializeArguments(ILoggingEvent event, JsonSerializer serializer) throws IOException {
         Object[] arguments = event.getArgumentArray();
         if (arguments != null) {

powertools-logging/powertools-logging-logback/src/main/java/software/amazon/lambda/powertools/logging/logback/LambdaEcsEncoder.java

@@ -98,7 +98,8 @@ public byte[] headerBytes() {
     @SuppressWarnings("java:S106")
     @Override
     public byte[] encode(ILoggingEvent event) {
-        final Map<String, String> mdcPropertyMap = event.getMDCPropertyMap();
+        final Map<String, String> mdcPropertyMap = new TreeMap<>(event.getMDCPropertyMap());
+        mdcPropertyMap.putAll(getKeyValuePairs(event));
 
         StringBuilder builder = new StringBuilder();
         try (JsonSerializer serializer = new JsonSerializer(builder)) {
@@ -131,8 +132,6 @@ public byte[] encode(ILoggingEvent event) {
 
             serializeMDCEntries(mdcPropertyMap, serializer);
 
-            serializeKeyValuePairs(event, serializer);
-
             serializeArguments(event, serializer);
 
             serializer.writeEndObject();
@@ -143,14 +142,11 @@ public byte[] encode(ILoggingEvent event) {
         return builder.toString().getBytes(UTF_8);
     }
 
-    private void serializeKeyValuePairs(ILoggingEvent event, JsonSerializer serializer) {
-        Optional.ofNullable(event.getKeyValuePairs())
+    private Map<String, String> getKeyValuePairs(ILoggingEvent event) {
+        return Optional.ofNullable(event.getKeyValuePairs())
                 .orElse(Collections.emptyList()).stream()
                 .filter(Objects::nonNull)
-                .map(kvp -> new AbstractMap.SimpleEntry<>(String.valueOf(kvp.key), kvp.value))
-                .filter(kvp -> !PowertoolsLoggedFields.stringValues().contains(kvp.getKey()))
-                .sorted(Map.Entry.comparingByKey())
-                .forEach(kvp -> serializeKVPEntry(kvp.getKey(), kvp.getValue(), serializer));
+                .collect(TreeMap::new, (map, kvp) -> map.put(String.valueOf(kvp.key), String.valueOf(kvp.value)), TreeMap::putAll);
     }
 
     private void serializeFunctionInfo(JsonSerializer serializer, String arn, Map<String, String> mdcPropertyMap) {

powertools-logging/powertools-logging-logback/src/main/java/software/amazon/lambda/powertools/logging/logback/LambdaJsonEncoder.java

@@ -79,12 +79,11 @@ public byte[] encode(ILoggingEvent event) {
             serializeException(event, serializer);
 
             TreeMap<String, String> sortedMap = new TreeMap<>(event.getMDCPropertyMap());
+            sortedMap.putAll(getKeyValuePairs(event));
             serializePowertools(sortedMap, serializer);
 
             serializeMDCEntries(sortedMap, serializer);
 
-            serializeKeyValuePairs(event, serializer);
-
             serializeArguments(event, serializer);
 
             serializeThreadInfo(event, serializer);
@@ -101,14 +100,11 @@ public byte[] encode(ILoggingEvent event) {
         return builder.toString().getBytes(UTF_8);
     }
 
-    private void serializeKeyValuePairs(ILoggingEvent event, JsonSerializer serializer) {
-        Optional.ofNullable(event.getKeyValuePairs())
+    private Map<String, String> getKeyValuePairs(ILoggingEvent event) {
+        return Optional.ofNullable(event.getKeyValuePairs())
                 .orElse(Collections.emptyList()).stream()
                 .filter(Objects::nonNull)
-                .map(kvp -> new AbstractMap.SimpleEntry<>(String.valueOf(kvp.key), kvp.value))
-                .filter(kvp -> !PowertoolsLoggedFields.stringValues().contains(kvp.getKey()))
-                .sorted(Map.Entry.comparingByKey())
-                .forEach(kvp -> serializeKVPEntry(kvp.getKey(), kvp.getValue(), serializer));
+                .collect(TreeMap::new, (map, kvp) -> map.put(String.valueOf(kvp.key), String.valueOf(kvp.value)), TreeMap::putAll);
     }
 
     private void serializeThreadInfo(ILoggingEvent event, JsonSerializer serializer) {

powertools-logging/powertools-logging-logback/src/test/java/software/amazon/lambda/powertools/logging/internal/LambdaEcsEncoderTest.java

@@ -188,7 +188,7 @@ void shouldLogKeyValuePairs() {
         LambdaEcsEncoder encoder = new LambdaEcsEncoder();
         encoder.start();
 
-        LoggingEvent keyValuePairsLoggingEvent = new LoggingEvent("fqcn", logger, Level.INFO, "Key Value Pairs Test with argument: {}",
+        LoggingEvent keyValuePairsLoggingEvent = new LoggingEvent("fqcn", logger, Level.INFO, "Key Value Pairs Test",
                 null, new Object[0]);
 
         keyValuePairsLoggingEvent.setKeyValuePairs(List.of(
@@ -211,7 +211,7 @@ void shouldLogKeyValuePairs() {
                 .contains("\"key_01_string\":\"value_01\"")
                 .contains("\"key_02_numeric\":2")
                 .contains("\"key_03_decimal\":2.333")
-                .contains("\"key_04_null\":null")
+                .contains("\"key_04_null\":\"null\"")
                 .contains("\"\":\"value_05_empty_key\"")
                 .contains("\"null\":\"value_06_null_key\"")
                 .contains("\"key_07_boolean_true\":true")

powertools-logging/powertools-logging-logback/src/test/java/software/amazon/lambda/powertools/logging/internal/LambdaJsonEncoderTest.java

@@ -450,7 +450,7 @@ void shouldLogKeyValuePairs() {
         LambdaJsonEncoder encoder = new LambdaJsonEncoder();
         encoder.start();
 
-        LoggingEvent keyValuePairsLoggingEvent = new LoggingEvent("fqcn", logger, Level.INFO, "Key Value Pairs Test with argument: {}",
+        LoggingEvent keyValuePairsLoggingEvent = new LoggingEvent("fqcn", logger, Level.INFO, "Key Value Pairs Test",
                 null, new Object[0]);
 
         keyValuePairsLoggingEvent.setKeyValuePairs(List.of(
@@ -473,7 +473,7 @@ void shouldLogKeyValuePairs() {
                 .contains("\"key_01_string\":\"value_01\"")
                 .contains("\"key_02_numeric\":2")
                 .contains("\"key_03_decimal\":2.333")
-                .contains("\"key_04_null\":null")
+                .contains("\"key_04_null\":\"null\"")
                 .contains("\"\":\"value_05_empty_key\"")
                 .contains("\"null\":\"value_06_null_key\"")
                 .contains("\"key_07_boolean_true\":true")