XRENDERING-621: Make rendering errors translatables and extendables

* simplify the API
* make the code more reusable

xwiki-rendering-api/src/main/java/org/xwiki/rendering/internal/util/DefaultErrorBlockGenerator.java

@@ -28,9 +28,15 @@
 import javax.inject.Inject;
 import javax.inject.Singleton;
 
+import org.apache.commons.lang3.ArrayUtils;
+import org.apache.commons.lang3.StringUtils;
 import org.apache.commons.lang3.exception.ExceptionUtils;
 import org.slf4j.Logger;
 import org.xwiki.component.annotation.Component;
+import org.xwiki.logging.LogLevel;
+import org.xwiki.logging.LogUtils;
+import org.xwiki.logging.event.LogEvent;
+import org.xwiki.logging.marker.TranslationMarker;
 import org.xwiki.rendering.block.Block;
 import org.xwiki.rendering.block.FormatBlock;
 import org.xwiki.rendering.block.GroupBlock;
@@ -55,7 +61,21 @@ public class DefaultErrorBlockGenerator implements ErrorBlockGenerator
     protected Logger logger;
 
     @Override
-    public List<Block> generateErrorBlocks(String message, String description, boolean isInline)
+    public List<Block> generateErrorBlocks(boolean inline, String messageId, String defaultMessage,
+        String defaultDescription, Object... arguments)
+    {
+        LogEvent message = LogUtils.newLogEvent(messageId != null ? new TranslationMarker(messageId) : null,
+            LogLevel.ERROR,
+            defaultMessage != null && !defaultMessage.endsWith(".") ? defaultMessage + '.' : defaultMessage, arguments);
+        LogEvent description = defaultDescription != null
+            ? LogUtils.newLogEvent(messageId != null ? new TranslationMarker(messageId + ".description") : null,
+                LogLevel.ERROR, defaultDescription, arguments)
+            : null;
+
+        return generateErrorBlocks(inline, message, description);
+    }
+
+    protected List<Block> generateErrorBlocks(boolean inline, LogEvent message, LogEvent description)
     {
         List<Block> errorBlocks = new ArrayList<>();
 
@@ -64,39 +84,80 @@ public List<Block> generateErrorBlocks(String message, String description, boole
         Map<String, String> errorDescriptionBlockParams =
             Collections.singletonMap(CLASS_ATTRIBUTE_NAME, CLASS_ATTRIBUTE_DESCRIPTION_VALUE);
 
-        Block descriptionBlock = new VerbatimBlock(description, isInline);
+        StringBuilder messageBuilder = new StringBuilder();
+
+        if (StringUtils.isNotEmpty(message.getMessage())) {
+            messageBuilder.append(message.getFormattedMessage());
+        }
+
+        List<Block> descriptionChildren = new ArrayList<>();
 
-        if (isInline) {
-            errorBlocks.add(new FormatBlock(Arrays.asList(new WordBlock(message)), Format.NONE, errorBlockParams));
-            errorBlocks.add(new FormatBlock(Arrays.asList(descriptionBlock), Format.NONE, errorDescriptionBlockParams));
+        // Description
+        addDescriptionBlock(inline, description, descriptionChildren);
+
+        // Stack trace
+        addStackTraceBlock(inline, message, messageBuilder, descriptionChildren);
+
+        if (!descriptionChildren.isEmpty()) {
+            messageBuilder.append(" Click on this message for details.");
+        }
+
+        if (inline) {
+            errorBlocks.add(new FormatBlock(Arrays.asList(new WordBlock(messageBuilder.toString())), Format.NONE,
+                errorBlockParams));
+            if (!descriptionChildren.isEmpty()) {
+                errorBlocks.add(new FormatBlock(descriptionChildren, Format.NONE, errorDescriptionBlockParams));
+            }
         } else {
-            errorBlocks.add(new GroupBlock(Arrays.asList(new WordBlock(message)), errorBlockParams));
-            errorBlocks.add(new GroupBlock(Arrays.asList(descriptionBlock), errorDescriptionBlockParams));
+            errorBlocks
+                .add(new GroupBlock(Arrays.asList(new WordBlock(message.getFormattedMessage())), errorBlockParams));
+            if (!descriptionChildren.isEmpty()) {
+                errorBlocks.add(new GroupBlock(descriptionChildren, errorDescriptionBlockParams));
+            }
         }
 
         return errorBlocks;
     }
 
-    @Override
-    public List<Block> generateErrorBlocks(String messagePrefix, Throwable throwable, boolean isInline)
+    private void addDescriptionBlock(boolean inline, LogEvent description, List<Block> descriptionChildren)
     {
-        // Note: We're using ExceptionUtils.getRootCause(e).getMessage() instead of getRootCauseMessage()
-        // below because getRootCauseMessage() adds a technical prefix (the name of the exception), that
-        // we don't want to display to our users.
-        Throwable rootCause = ExceptionUtils.getRootCause(throwable);
-        if (rootCause == null) {
-            // If there's no nested exception, fall back to the throwable itself for getting the cause
-            rootCause = throwable;
+        if (description != null) {
+            descriptionChildren.add(new VerbatimBlock(description.getFormattedMessage(), inline));
         }
+    }
+
+    private void addStackTraceBlock(boolean inline, LogEvent message, StringBuilder messageBuilder,
+        List<Block> descriptionChildren)
+    {
+        if (message.getThrowable() != null) {
+            // Note: We're using ExceptionUtils.getRootCause(e).getMessage() instead of getRootCauseMessage()
+            // below because getRootCauseMessage() adds a technical prefix (the name of the exception), that
+            // we don't want to display to our users.
+            Throwable rootCause = ExceptionUtils.getRootCause(message.getThrowable());
+            if (rootCause == null) {
+                // If there's no nested exception, fall back to the throwable itself for getting the cause
+                rootCause = message.getThrowable();
+            }
 
-        String augmentedMessage = String.format("%s%s", messagePrefix,
-            rootCause == null ? "" : String.format(". Cause: [%s]", rootCause.getMessage()));
-        augmentedMessage = String.format("%s%sClick on this message for details.", augmentedMessage,
-            augmentedMessage.trim().endsWith(".") ? " " : ". ");
+            descriptionChildren.add(new VerbatimBlock(ExceptionUtils.getStackTrace(message.getThrowable()), inline));
 
-        this.logger.debug(augmentedMessage);
+            // Also add more details to the message
+            messageBuilder.append(" Cause: [");
+            messageBuilder.append(rootCause.getMessage());
+            messageBuilder.append("].");
+        }
+    }
 
-        return generateErrorBlocks(augmentedMessage, ExceptionUtils.getStackTrace(throwable), isInline);
+    @Override
+    public List<Block> generateErrorBlocks(String message, String description, boolean isInline)
+    {
+        return generateErrorBlocks(isInline, null, message, description, ArrayUtils.EMPTY_OBJECT_ARRAY);
+    }
+
+    @Override
+    public List<Block> generateErrorBlocks(String messagePrefix, Throwable throwable, boolean isInline)
+    {
+        return generateErrorBlocks(isInline, null, messagePrefix, null, throwable);
     }
 
     @Override

xwiki-rendering-api/src/main/java/org/xwiki/rendering/util/ErrorBlockGenerator.java

@@ -102,8 +102,8 @@
      * context depending on the implementation of this component.
      * 
      * @param inline whether the generated blocks should be inline or not
-     * @param marker a marker associated to the message. It's recommended to at least pass a {@link TranslationMarker}
-     *            to indicate how to translate the message.
+     * @param messageId an identifier associated to the message. It's generally used, among other things, to find a
+     *            translation for the message and the description in implementation which supports it.
      * @param defaultMessage the default message following SLF4J's {@link Logger} syntax
      * @param defaultDescription the default description following SLF4J's {@link Logger} syntax
      * @param arguments a list arguments to insert in the message and the description and/or a {@link Throwable}
@@ -111,9 +111,10 @@
      * @since 14.0RC1
      */
     @Unstable
-    default List<Block> generateErrorBlocks(boolean inline, Marker marker, String defaultMessage,
+    default List<Block> generateErrorBlocks(boolean inline, String messageId, String defaultMessage,
         String defaultDescription, Object... arguments)
     {
+        Marker marker = new TranslationMarker(messageId);
         LogEvent message = LogUtils.newLogEvent(marker, LogLevel.ERROR, defaultMessage, arguments);
 
         if (message.getThrowable() != null) {

xwiki-rendering-transformations/xwiki-rendering-transformation-macro/src/main/java/org/xwiki/rendering/internal/transformation/macro/MacroErrorManager.java

@@ -22,8 +22,6 @@
 import java.util.List;
 
 import org.slf4j.Logger;
-import org.slf4j.Marker;
-import org.xwiki.logging.marker.TranslationMarker;
 import org.xwiki.rendering.block.Block;
 import org.xwiki.rendering.block.MacroBlock;
 import org.xwiki.rendering.block.MacroMarkerBlock;
@@ -74,17 +72,17 @@ private Block wrapInMacroMarker(MacroBlock macroBlockToWrap, List<Block> newBloc
      * Generates Blocks to signify that the passed Macro Block has failed to execute.
      * 
      * @param macroToReplace
-     * @param marker a marker associated to the message. It's recommended to at least pass a {@link TranslationMarker}
-     *            to indicate how to translate the message.
+     * @param messageId an identifier associated to the message. It's generally used, among other things, to find a
+     *            translation for the message and the description in implementation which supports it.
      * @param defaultMessage the default message following SLF4J's {@link Logger} syntax
      * @param defaultDescription the default description following SLF4J's {@link Logger} syntax
      * @param arguments a list arguments to insert in the message and the description and/or a {@link Throwable}
      * @since 14.0RC1
      */
-    public void generateError(MacroBlock macroToReplace, Marker marker, String defaultMessage,
+    public void generateError(MacroBlock macroToReplace, String messageId, String defaultMessage,
         String defaultDescription, Object... arguments)
     {
-        List<Block> errorBlocks = this.errorBlockGenerator.generateErrorBlocks(macroToReplace.isInline(), marker,
+        List<Block> errorBlocks = this.errorBlockGenerator.generateErrorBlocks(macroToReplace.isInline(), messageId,
             defaultMessage, defaultDescription, arguments);
         macroToReplace.getParent().replaceChild(wrapInMacroMarker(macroToReplace, errorBlocks), macroToReplace);
     }

xwiki-rendering-transformations/xwiki-rendering-transformation-macro/src/main/java/org/xwiki/rendering/internal/transformation/macro/MacroTransformation.java

@@ -32,7 +32,6 @@
 import org.xwiki.component.annotation.Component;
 import org.xwiki.component.phase.Initializable;
 import org.xwiki.component.phase.InitializationException;
-import org.xwiki.logging.marker.TranslationMarker;
 import org.xwiki.properties.BeanManager;
 import org.xwiki.rendering.block.Block;
 import org.xwiki.rendering.block.MacroBlock;
@@ -68,15 +67,15 @@
 @Singleton
 public class MacroTransformation extends AbstractTransformation implements Initializable
 {
-    private static final TranslationMarker TM_UNKNOWNMACRO = new TranslationMarker("rendering.macro.error.unknown");
+    private static final String TM_UNKNOWNMACRO = "rendering.macro.error.unknown";
 
-    private static final TranslationMarker TM_FAILEDMACRO = new TranslationMarker("rendering.macro.error.failed");
+    private static final String TM_FAILEDMACRO = "rendering.macro.error.failed";
 
-    private static final TranslationMarker TM_INVALIDMACRO = new TranslationMarker("rendering.macro.error.invalid");
+    private static final String TM_INVALIDMACRO = "rendering.macro.error.invalid";
 
-    private static final TranslationMarker TM_STANDALONEMACRO = new TranslationMarker("rendering.macro.error.standalone");
+    private static final String TM_STANDALONEMACRO = "rendering.macro.error.standalone";
 
-    private static final TranslationMarker TM_INVALIDMACROPARAMETER = new TranslationMarker("rendering.macro.error.invalidParameter");
+    private static final String TM_INVALIDMACROPARAMETER = "rendering.macro.error.invalidParameter";
 
     private static class MacroLookupExceptionElement
     {