XWIKI-20266: Ability to restrict attachment upload based on mime types

- Explicit coverage for xwiki-platform-attachment-validation-api
- Provide a default implementation of AttachmentValidator with a low priority in oldcore

xwiki-platform-core/xwiki-platform-attachment/xwiki-platform-attachment-validation/xwiki-platform-attachment-validation-api/pom.xml

@@ -34,6 +34,7 @@
   <properties>
     <!-- Name to display by the Extension Manager -->
     <xwiki.extension.name>Attachment Validation API</xwiki.extension.name>
+    <xwiki.jacoco.instructionRatio>0.00</xwiki.jacoco.instructionRatio>
   </properties>
   <dependencies>
     <dependency>

xwiki-platform-core/xwiki-platform-oldcore/src/main/java/org/xwiki/internal/attachment/validation/VoidAttachmentValidator.java

+/*
+ * See the NOTICE file distributed with this work for additional
+ * information regarding copyright ownership.
+ *
+ * This is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This software is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this software; if not, write to the Free
+ * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
+ */
+package org.xwiki.internal.attachment.validation;
+
+import javax.inject.Inject;
+import javax.inject.Singleton;
+
+import org.slf4j.Logger;
+import org.xwiki.attachment.AttachmentAccessWrapper;
+import org.xwiki.attachment.validation.AttachmentValidationException;
+import org.xwiki.attachment.validation.AttachmentValidator;
+import org.xwiki.component.annotation.Component;
+
+/**
+ * Implementation of {@link AttachmentValidator} with a low priority ({@code 2000}) doing nothing but logging a debug
+ * trace. This is meant as a replacement in contexts where no actual implementation of {@link AttachmentValidator} is
+ * provided by another extension. The default expected extension is
+ * {@code xwiki-platform-attachment-validation-default}.
+ *
+ * @version $Id$
+ * @since 14.10RC1
+ */
+@Component
+@Singleton
+public class VoidAttachmentValidator implements AttachmentValidator
+{
+    @Inject
+    private Logger logger;
+
+    @Override
+    public void validateAttachment(AttachmentAccessWrapper wrapper) throws AttachmentValidationException
+    {
+        this.logger.debug("This is a minimal default implementation with a low priority. This component is expected "
+            + "to be replaced by an actual implementation in production.");
+    }
+}

xwiki-platform-core/xwiki-platform-oldcore/src/main/resources/META-INF/components.txt

@@ -265,3 +265,4 @@ com.xpn.xwiki.web.UnknownAction
 com.xpn.xwiki.web.UploadAction
 com.xpn.xwiki.web.ViewAction
 com.xpn.xwiki.web.ViewAttachRevAction
+2000:org.xwiki.internal.attachment.validation.VoidAttachmentValidator