XCOMMONS-3289: Allow overwritting xwiki.properties and xwiki.cfg properties via environment variable and Java system properties

xwiki-commons-core/xwiki-commons-configuration/pom.xml

@@ -33,6 +33,7 @@
   <description>XWiki Commons - Configuration - Parent POM</description>
   <modules>
     <module>xwiki-commons-configuration-api</module>
+    <module>xwiki-commons-configuration-default</module>
   </modules>
 </project>
 

xwiki-commons-core/xwiki-commons-configuration/xwiki-commons-configuration-api/src/main/java/org/xwiki/configuration/ConfigurationSource.java

@@ -23,6 +23,7 @@
 import java.util.Map;
 
 import org.xwiki.component.annotation.Role;
+import org.xwiki.stability.Unstable;
 
 /**
  * @version $Id$
@@ -66,9 +67,9 @@ default <T> T getProperty(String key, Class<T> valueClass, T defaultValue)
     {
         if (containsKey(key)) {
             return getProperty(key, valueClass);
-        } else {
-            return getProperty(key, defaultValue);
         }
+
+        return defaultValue;
     }
 
     /**
@@ -84,6 +85,17 @@ default <T> T getProperty(String key, Class<T> valueClass, T defaultValue)
      */
     List<String> getKeys();
 
+    /**
+     * @param prefix the prefix to filter the keys
+     * @return the list of available keys in the configuration source that start with the passed prefix
+     * @since 17.5.0RC1
+     */
+    @Unstable
+    default List<String> getKeys(String prefix)
+    {
+        return getKeys().stream().filter(key -> key.startsWith(prefix)).toList();
+    }
+
     /**
      * @param key the key to check
      * @return true if the key is present in the configuration source or false otherwise
@@ -95,6 +107,17 @@ default <T> T getProperty(String key, Class<T> valueClass, T defaultValue)
      */
     boolean isEmpty();
 
+    /**
+     * @param prefix the prefix to filter the keys
+     * @return true if the configuration source doesn't have any key or false otherwise
+     * @since 17.5.0RC1
+     */
+    @Unstable
+    default boolean isEmpty(String prefix)
+    {
+        return getKeys(prefix).isEmpty();
+    }
+
     /**
      * Set a property, this will replace any previously set values.
      *

xwiki-commons-core/xwiki-commons-configuration/xwiki-commons-configuration-api/src/main/java/org/xwiki/configuration/internal/AbstractCompositeConfigurationSource.java

@@ -0,0 +1,157 @@
+/*
+ * 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.configuration.internal;
+
+import java.util.ArrayList;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Set;
+
+import org.xwiki.configuration.ConfigurationSource;
+
+/**
+ * Base class for composing (aka chaining) several Configuration Sources. The order of sources is important. Sources
+ * located before other sources take priority.
+ * 
+ * @version $Id$
+ * @since 7.4M1
+ */
+public abstract class AbstractCompositeConfigurationSource extends AbstractConfigurationSource
+    implements Iterable<ConfigurationSource>
+{
+    @Override
+    public boolean containsKey(String key)
+    {
+        boolean result = false;
+
+        for (ConfigurationSource source : this) {
+            if (source.containsKey(key)) {
+                result = true;
+                break;
+            }
+        }
+
+        return result;
+    }
+
+    @Override
+    public <T> T getProperty(String key)
+    {
+        T result = null;
+
+        for (ConfigurationSource source : this) {
+            if (source.containsKey(key)) {
+                result = source.<T>getProperty(key);
+                break;
+            }
+        }
+
+        return result;
+    }
+
+    @Override
+    public <T> T getProperty(String key, Class<T> valueClass)
+    {
+        T result = null;
+
+        for (ConfigurationSource source : this) {
+            if (source.containsKey(key)) {
+                result = source.getProperty(key, valueClass);
+                break;
+            }
+        }
+
+        // List and Properties must return empty collections and not null values.
+        if (result == null) {
+            result = getDefault(valueClass);
+        }
+
+        return result;
+    }
+
+    @Override
+    public <T> T getProperty(String key, T defaultValue)
+    {
+        T result = null;
+
+        for (ConfigurationSource source : this) {
+            if (source.containsKey(key)) {
+                result = source.<T>getProperty(key, defaultValue);
+                break;
+            }
+        }
+
+        if (result == null) {
+            result = defaultValue;
+        }
+
+        return result;
+    }
+
+    @Override
+    public List<String> getKeys()
+    {
+        // We use a linked hash set in order to keep the keys in the order in which they were defined in the sources.
+        Set<String> keys = new LinkedHashSet<>();
+
+        for (ConfigurationSource source : this) {
+            keys.addAll(source.getKeys());
+        }
+
+        return new ArrayList<>(keys);
+    }
+
+    @Override
+    public List<String> getKeys(String prefix)
+    {
+        // We use a linked hash set in order to keep the keys in the order in which they were defined in the sources.
+        Set<String> keys = new LinkedHashSet<>();
+
+        for (ConfigurationSource source : this) {
+            keys.addAll(source.getKeys(prefix));
+        }
+
+        return new ArrayList<>(keys);
+    }
+
+    @Override
+    public boolean isEmpty()
+    {
+        for (ConfigurationSource source : this) {
+            if (!source.isEmpty()) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    @Override
+    public boolean isEmpty(String prefix)
+    {
+        for (ConfigurationSource source : this) {
+            if (!source.isEmpty(prefix)) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+}

xwiki-commons-core/xwiki-commons-configuration/xwiki-commons-configuration-api/src/main/java/org/xwiki/configuration/internal/CompositeConfigurationSource.java

@@ -0,0 +1,55 @@
+/*
+ * 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.configuration.internal;
+
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+
+import org.xwiki.configuration.ConfigurationSource;
+
+/**
+ * Allows composing (aka chaining) several Configuration Sources. The order of sources is important. Sources located
+ * before other sources take priority.
+ * 
+ * @version $Id$
+ * @since 2.0M1
+ */
+public class CompositeConfigurationSource extends AbstractCompositeConfigurationSource
+{
+    /**
+     * The order of sources is important. Sources located before other sources take priority.
+     */
+    protected List<ConfigurationSource> sources = new ArrayList<>();
+
+    /**
+     * @param source the source to add to the list of sources
+     */
+    public void addConfigurationSource(ConfigurationSource source)
+    {
+        this.sources.add(source);
+    }
+
+    @Override
+    public Iterator<ConfigurationSource> iterator()
+    {
+        return this.sources.iterator();
+    }
+}

xwiki-commons-core/xwiki-commons-configuration/xwiki-commons-configuration-api/src/main/java/org/xwiki/configuration/internal/ConfigurationSourceDecorator.java

@@ -90,6 +90,12 @@ public List<String> getKeys()
         return executeRead(() -> getWrappedConfigurationSource().getKeys());
     }
 
+    @Override
+    public List<String> getKeys(String prefix)
+    {
+        return executeRead(() -> getWrappedConfigurationSource().getKeys(prefix));
+    }
+
     @Override
     public boolean containsKey(String key)
     {
@@ -102,6 +108,12 @@ public boolean isEmpty()
         return executeRead(() -> getWrappedConfigurationSource().isEmpty());
     }
 
+    @Override
+    public boolean isEmpty(String prefix)
+    {
+        return executeRead(() -> getWrappedConfigurationSource().isEmpty(prefix));
+    }
+
     @Override
     public void setProperties(Map<String, Object> properties) throws ConfigurationSaveException
     {