Ensure scripts are processed before their references

Alters AbstractConfiguration to process the Scripts element before other components. This allows ScriptRef elements to be resolved correctly, regardless of their order in the configuration file.

Author: jhl221123

log4j-core-test/src/test/java/org/apache/logging/log4j/core/config/AbstractConfigurationTest.java

@@ -24,14 +24,19 @@
 import java.util.Map;
 import java.util.Map.Entry;
 import org.apache.logging.log4j.core.LoggerContext;
+import org.apache.logging.log4j.core.filter.CompositeFilter;
+import org.apache.logging.log4j.core.filter.ScriptFilter;
 import org.apache.logging.log4j.core.lookup.Interpolator;
 import org.apache.logging.log4j.core.lookup.InterpolatorTest;
 import org.apache.logging.log4j.core.lookup.StrSubstitutor;
+import org.apache.logging.log4j.core.test.junit.LoggerContextSource;
+import org.apache.logging.log4j.test.junit.SetTestProperty;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.ValueSource;
 import org.junitpioneer.jupiter.Issue;
 
+@SetTestProperty(key = "log4j2.scriptEnableLanguages", value = "groovy")
 class AbstractConfigurationTest {
 
     @Test
@@ -60,6 +65,26 @@ void substitutorHasConfigurationAndLoggerContext(final boolean hasProperties) {
         }
     }
 
+    @Test
+    @LoggerContextSource("log4j2-script-order-test.xml")
+    void scriptRefShouldBeResolvedWhenScriptsElementIsLast(final Configuration config) {
+        assertThat(config.getFilter())
+                .as("Top-level filter should be a CompositeFilter")
+                .isInstanceOf(CompositeFilter.class);
+        final CompositeFilter compositeFilter = (CompositeFilter) config.getFilter();
+
+        assertThat(compositeFilter.getFilters())
+                .as("CompositeFilter should contain one filter")
+                .hasSize(1);
+        final ScriptFilter scriptFilter =
+                (ScriptFilter) compositeFilter.getFilters().get(0);
+
+        assertThat(scriptFilter).isNotNull();
+        assertThat(scriptFilter.toString())
+                .as("Script name should match the one in the config")
+                .isEqualTo("GLOBAL_FILTER");
+    }
+
     private static class TestConfiguration extends AbstractConfiguration {
 
         private final Map<String, String> map;

log4j-core-test/src/test/resources/log4j2-script-order-test.xml

@@ -0,0 +1,31 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  ~ Licensed to the Apache Software Foundation (ASF) under one or more
+  ~ contributor license agreements.  See the NOTICE file distributed with
+  ~ this work for additional information regarding copyright ownership.
+  ~ The ASF licenses this file to you under the Apache License, Version 2.0
+  ~ (the "License"); you may not use this file except in compliance with
+  ~ the License.  You may obtain a copy of the License at
+  ~
+  ~      http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  -->
+<Configuration status="WARN">
+    <Filters>
+        <ScriptFilter onMatch="ACCEPT" onMisMatch="DENY">
+            <ScriptRef ref="GLOBAL_FILTER"/>
+        </ScriptFilter>
+    </Filters>
+
+    <Scripts>
+        <Script name="GLOBAL_FILTER" language="groovy"><![CDATA[
+        // simple script
+        return true
+    ]]></Script>
+    </Scripts>
+</Configuration>

log4j-core/src/main/java/org/apache/logging/log4j/core/config/AbstractConfiguration.java

@@ -682,13 +682,14 @@ protected void doConfigure() {
         preConfigure(rootNode);
         configurationScheduler.start();
         // Find the "Properties" node first
+        final List<Node> children = rootNode.getChildren();
         boolean hasProperties = false;
-        for (final Node node : rootNode.getChildren()) {
-            if ("Properties".equalsIgnoreCase(node.getName())) {
+        for (final Node child : children) {
+            if ("Properties".equalsIgnoreCase(child.getName())) {
                 hasProperties = true;
-                createConfiguration(node, null);
-                if (node.getObject() != null) {
-                    final StrLookup lookup = node.getObject();
+                createConfiguration(child, null);
+                if (child.getObject() != null) {
+                    final StrLookup lookup = child.getObject();
                     runtimeStrSubstitutor.setVariableResolver(lookup);
                     configurationStrSubstitutor.setVariableResolver(lookup);
                 }
@@ -705,28 +706,36 @@ protected void doConfigure() {
             configurationStrSubstitutor.setVariableResolver(interpolator);
         }
 
+        for (final Node child : children) {
+            if ("Scripts".equalsIgnoreCase(child.getName())) {
+                createConfiguration(child, null);
+                if (child.getObject() != null) {
+                    for (final AbstractScript script : child.getObject(AbstractScript[].class)) {
+                        if (script instanceof ScriptRef) {
+                            LOGGER.error(
+                                    "Script reference to {} not added. Scripts definition cannot contain script references",
+                                    script.getName());
+                        } else if (scriptManager != null) {
+                            scriptManager.addScript(script);
+                        }
+                    }
+                }
+                break;
+            }
+        }
+
         boolean setLoggers = false;
         boolean setRoot = false;
-        for (final Node child : rootNode.getChildren()) {
-            if ("Properties".equalsIgnoreCase(child.getName())) {
+        for (final Node child : children) {
+            if ("Properties".equalsIgnoreCase(child.getName()) || "Scripts".equalsIgnoreCase(child.getName())) {
                 // We already used this node
                 continue;
             }
             createConfiguration(child, null);
             if (child.getObject() == null) {
                 continue;
             }
-            if ("Scripts".equalsIgnoreCase(child.getName())) {
-                for (final AbstractScript script : child.getObject(AbstractScript[].class)) {
-                    if (script instanceof ScriptRef) {
-                        LOGGER.error(
-                                "Script reference to {} not added. Scripts definition cannot contain script references",
-                                script.getName());
-                    } else if (scriptManager != null) {
-                        scriptManager.addScript(script);
-                    }
-                }
-            } else if ("Appenders".equalsIgnoreCase(child.getName())) {
+            if ("Appenders".equalsIgnoreCase(child.getName())) {
                 appenders = child.getObject();
             } else if (child.isInstanceOf(Filter.class)) {
                 addFilter(child.getObject(Filter.class));

src/changelog/.2.x.x/3336_script_resolution_order_fix.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<entry xmlns="https://logging.apache.org/xml/ns"
+       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+       xsi:schemaLocation="
+           https://logging.apache.org/xml/ns
+           https://logging.apache.org/xml/ns/log4j-changelog-0.xsd"
+       type="fixed">
+    <issue id="3336" link="https://github.com/apache/logging-log4j2/issues/3336"/>
+    <description format="asciidoc">
+        Fix script resolution failure when the Scripts element is placed after a ScriptRef in the configuration.
+    </description>
+</entry>