[EAK-504] Limited Parsys: add functionality to limit parsys-like components child component count

core/src/main/java/com/exadel/aem/toolkit/api/annotations/policies/MaxChildren.java

@@ -0,0 +1,40 @@
+/*
+ * Licensed 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.
+ */
+package com.exadel.aem.toolkit.api.annotations.policies;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.RUNTIME)
+public @interface MaxChildren {
+    /**
+     * Specifies the maximum number of children allowed for container component
+     * @return Long value, 0 or greater
+     */
+    long value();
+
+    /**
+     * Used to specify target node for max children limit. The limitation applies to the current annotated component
+     * if set to {@link PolicyTarget#CURRENT}. Otherwise, the limitation is applied to a container nested within the current
+     * component. E.g. if the current component is an inheritor of parsys, setting {@code targetContainer} to {@link
+     * PolicyTarget#CURRENT} means that the limitation affects which components can be added to the current
+     * one. But if the current component contains a parsys inside you need to skip {@code targetContainer} or set it to
+     * {@link PolicyTarget#CHILD} so that the limitation applies to the parsys.
+     * @return {@link PolicyTarget} value
+     */
+    PolicyTarget targetContainer() default PolicyTarget.CHILD;
+}

core/src/main/java/com/exadel/aem/toolkit/api/annotations/policies/PolicyTarget.java

@@ -14,7 +14,7 @@
 package com.exadel.aem.toolkit.api.annotations.policies;
 
 /**
- * Defines possible values of {@link AllowedChildren#targetContainer()} property
+ * Defines possible values of {@link AllowedChildren#targetContainer()} and {@link MaxChildren#targetContainer()} properties
  */
 public enum PolicyTarget {
     CHILD,

plugin/src/main/java/com/exadel/aem/toolkit/plugin/handlers/Handlers.java

@@ -28,6 +28,7 @@
 import com.exadel.aem.toolkit.plugin.handlers.common.CqDialogHandler;
 import com.exadel.aem.toolkit.plugin.handlers.common.CqEditConfigHandler;
 import com.exadel.aem.toolkit.plugin.handlers.common.CqHtmlTagHandler;
+import com.exadel.aem.toolkit.plugin.handlers.common.MaxChildrenHandler;
 import com.exadel.aem.toolkit.plugin.handlers.common.PropertyMappingHandler;
 import com.exadel.aem.toolkit.plugin.handlers.dependson.DependsOnHandler;
 import com.exadel.aem.toolkit.plugin.handlers.editconfig.DropTargetsHandler;
@@ -54,12 +55,17 @@ public class Handlers {
     private static final BiConsumer<Source, Target> CASUAL_ANNOTATIONS_HANDLER = new CasualAnnotationsHandler();
     private static final BiConsumer<Source, Target> PROPERTY_MAPPING_HANDLER = new PropertyMappingHandler();
     private static final BiConsumer<Source, Target> ALLOWED_CHILDREN_HANDLER = new AllowedChildrenHandler();
+    private static final BiConsumer<Source, Target> MAX_CHILDREN_HANDLER = new MaxChildrenHandler();
 
     // UI-specific handlers
-    private static final BiConsumer<Source, Target> CHILD_EDIT_CONFIG_HANDLER = new CqChildEditConfigHandler().andThen(ALLOWED_CHILDREN_HANDLER);
+    private static final BiConsumer<Source, Target> CHILD_EDIT_CONFIG_HANDLER = new CqChildEditConfigHandler()
+        .andThen(ALLOWED_CHILDREN_HANDLER)
+        .andThen(MAX_CHILDREN_HANDLER);
     private static final BiConsumer<Source, Target> COMPONENT_HANDLER = new ComponentHandler();
     private static final BiConsumer<Source, Target> DIALOG_HANDLER = new CqDialogHandler();
-    private static final BiConsumer<Source, Target> EDIT_CONFIG_HANDLER = new CqEditConfigHandler().andThen(ALLOWED_CHILDREN_HANDLER);
+    private static final BiConsumer<Source, Target> EDIT_CONFIG_HANDLER = new CqEditConfigHandler()
+        .andThen(ALLOWED_CHILDREN_HANDLER)
+        .andThen(MAX_CHILDREN_HANDLER);
     private static final BiConsumer<Source, Target> HTML_TAG_HANDLER = new CqHtmlTagHandler();
     private static final Map<String, BiConsumer<Source, Target>> UI_HANDLERS = ImmutableMap.<String, BiConsumer<Source, Target>>builder()
         .put(Scopes.COMPONENT, COMPONENT_HANDLER)

plugin/src/main/java/com/exadel/aem/toolkit/plugin/handlers/common/MaxChildrenHandler.java

@@ -0,0 +1,76 @@
+/*
+ * Licensed 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.
+ */
+package com.exadel.aem.toolkit.plugin.handlers.common;
+
+import com.exadel.aem.toolkit.api.annotations.meta.Scopes;
+import com.exadel.aem.toolkit.api.annotations.policies.MaxChildren;
+import com.exadel.aem.toolkit.api.annotations.policies.PolicyTarget;
+import com.exadel.aem.toolkit.api.handlers.Handler;
+import com.exadel.aem.toolkit.api.handlers.Source;
+import com.exadel.aem.toolkit.api.handlers.Target;
+import com.exadel.aem.toolkit.plugin.utils.DialogConstants;
+
+/**
+ * Implements {@code BiConsumer} to populate a {@link Target} instance with properties originating from a {@link Source}
+ * object. The source refers to the {@code resolvemaxchildren} listener of the {@code
+ * cq:editConfig} node of an AEM component
+ */
+public class MaxChildrenHandler implements Handler {
+    /**
+     * Name of the listener to resolve max children limit for `policies` js module
+     */
+    public static final String MAX_LIMIT_RESOLVER_NAME = "resolvemaxchildren";
+
+    /**
+     * Format of default max children limit resolver
+     */
+    private static final String MAX_LIMIT_RESOLVER_FORMAT = "() => %d";
+
+
+    /**
+     * Processes data that can be extracted from the given {@code Source} and stores it into the provided {@code
+     * Target}
+     * @param source {@code Source} object used for data retrieval
+     * @param target Resulting {@code Target} object
+     */
+    @Override
+    public void accept(Source source, Target target) {
+        source.tryAdaptTo(MaxChildren.class).ifPresent(adaptation -> populate(adaptation, target));
+    }
+
+    /**
+     * Processes data from {@code MaxChildren} annotation and stores it into 'cq:listeners' node of the provided
+     * {@code Target}
+     * @param rule  {@code MaxChildren} object used for data retrieval
+     * @param target Resulting {@code Target} object
+     */
+    private static void populate(MaxChildren rule, Target target) {
+        if (isEditConfig(target) == (PolicyTarget.CURRENT == rule.targetContainer())) {
+            target
+                .attribute(DialogConstants.PN_PRIMARY_TYPE, DialogConstants.NT_EDIT_CONFIG)
+                .getOrCreateTarget(DialogConstants.NN_LISTENERS)
+                .attribute(DialogConstants.PN_PRIMARY_TYPE, DialogConstants.NT_LISTENERS)
+                .attribute(MAX_LIMIT_RESOLVER_NAME, String.format(MAX_LIMIT_RESOLVER_FORMAT, rule.value()));
+        }
+    }
+
+    /**
+     * Gets whether the given {@link Target} is a representation of a {@code cq:editConfig} node of an AEM component
+     * @param target {@code Target} instance
+     * @return True if the target is a {@code cq:editConfig} node; otherwise, false
+     */
+    private static boolean isEditConfig(Target target) {
+        return Scopes.CQ_EDIT_CONFIG.equals(target.getScope());
+    }
+}

plugin/src/main/java/com/exadel/aem/toolkit/plugin/writers/CqChildEditConfigWriter.java

@@ -19,6 +19,7 @@
 import com.exadel.aem.toolkit.api.annotations.editconfig.ChildEditConfig;
 import com.exadel.aem.toolkit.api.annotations.meta.Scopes;
 import com.exadel.aem.toolkit.api.annotations.policies.AllowedChildren;
+import com.exadel.aem.toolkit.api.annotations.policies.MaxChildren;
 import com.exadel.aem.toolkit.api.annotations.policies.PolicyTarget;
 import com.exadel.aem.toolkit.api.handlers.Source;
 
@@ -55,6 +56,8 @@ boolean canProcess(Source source) {
         Class<?> componentClass = (Class<?>) source.adaptTo(Class.class);
         return componentClass.isAnnotationPresent(ChildEditConfig.class)
                 || Arrays.stream(componentClass.getAnnotationsByType(AllowedChildren.class))
+                .anyMatch(ac -> PolicyTarget.CHILD.equals(ac.targetContainer()))
+                || Arrays.stream(componentClass.getAnnotationsByType(MaxChildren.class))
                 .anyMatch(ac -> PolicyTarget.CHILD.equals(ac.targetContainer()));
     }
 }

plugin/src/main/java/com/exadel/aem/toolkit/plugin/writers/CqEditConfigWriter.java

@@ -19,6 +19,7 @@
 import com.exadel.aem.toolkit.api.annotations.editconfig.EditConfig;
 import com.exadel.aem.toolkit.api.annotations.meta.Scopes;
 import com.exadel.aem.toolkit.api.annotations.policies.AllowedChildren;
+import com.exadel.aem.toolkit.api.annotations.policies.MaxChildren;
 import com.exadel.aem.toolkit.api.annotations.policies.PolicyTarget;
 import com.exadel.aem.toolkit.api.handlers.Source;
 
@@ -56,6 +57,8 @@ boolean canProcess(Source source) {
         Class<?> componentClass = (Class<?>) source.adaptTo(Class.class);
         return componentClass.isAnnotationPresent(EditConfig.class)
                 || Arrays.stream(componentClass.getAnnotationsByType(AllowedChildren.class))
+                .anyMatch(ac -> PolicyTarget.CURRENT.equals(ac.targetContainer()))
+                || Arrays.stream(componentClass.getAnnotationsByType(MaxChildren.class))
                 .anyMatch(ac -> PolicyTarget.CURRENT.equals(ac.targetContainer()));
     }
 }

plugin/src/test/com/exadel/aem/toolkit/plugin/AllTests.java

@@ -24,6 +24,7 @@
 import com.exadel.aem.toolkit.plugin.handlers.common.ComponentsTest;
 import com.exadel.aem.toolkit.plugin.handlers.common.EditConfigTest;
 import com.exadel.aem.toolkit.plugin.handlers.common.IgnoreFreshnessTest;
+import com.exadel.aem.toolkit.plugin.handlers.common.MaxChildrenTest;
 import com.exadel.aem.toolkit.plugin.handlers.common.WriteModeTest;
 import com.exadel.aem.toolkit.plugin.handlers.dependson.DependsOnTest;
 import com.exadel.aem.toolkit.plugin.handlers.placement.CoincidenceTest;
@@ -63,6 +64,7 @@
     AllowedChildrenTest.class,
     DependsOnTest.class,
     IgnoreFreshnessTest.class,
+    MaxChildrenTest.class,
 
     LayoutTest.class,
     ReplacementTest.class,

plugin/src/test/com/exadel/aem/toolkit/plugin/handlers/common/MaxChildrenTest.java

@@ -0,0 +1,29 @@
+package com.exadel.aem.toolkit.plugin.handlers.common;
+
+import org.junit.ClassRule;
+import org.junit.Rule;
+import org.junit.Test;
+
+import com.exadel.aem.toolkit.plugin.handlers.common.cases.maxchildren.MaxChildrenTestCases;
+import com.exadel.aem.toolkit.plugin.maven.FileSystemRule;
+import com.exadel.aem.toolkit.plugin.maven.PluginContextRenderingRule;
+
+public class MaxChildrenTest {
+
+    @ClassRule
+    public static FileSystemRule fileSystemHost = new FileSystemRule();
+
+    @Rule
+    public PluginContextRenderingRule pluginContext = new PluginContextRenderingRule(fileSystemHost.getFileSystem());
+
+    @Test
+    public void testSimpleAnnotation() {
+        pluginContext.test(MaxChildrenTestCases.SimpleMaxLimitAnnotation.class, "handlers/common/maxChildren/simple");
+    }
+
+    @Test
+    public void testAllowedChildrenWithMaxLimitConflict() {
+        pluginContext.test(MaxChildrenTestCases.AllowedChildrenWithMaxLimit.class, "handlers/common/maxChildren/withAllowedChildren");
+    }
+
+}

plugin/src/test/com/exadel/aem/toolkit/plugin/handlers/common/cases/maxchildren/MaxChildrenTestCases.java

@@ -0,0 +1,32 @@
+package com.exadel.aem.toolkit.plugin.handlers.common.cases.maxchildren;
+
+import com.exadel.aem.toolkit.api.annotations.main.AemComponent;
+import com.exadel.aem.toolkit.api.annotations.policies.AllowedChildren;
+import com.exadel.aem.toolkit.api.annotations.policies.MaxChildren;
+import com.exadel.aem.toolkit.api.annotations.policies.PolicyMergeMode;
+import com.exadel.aem.toolkit.plugin.handlers.common.cases.components.ComplexComponent1;
+import com.exadel.aem.toolkit.plugin.handlers.common.cases.components.ComplexComponent2;
+import com.exadel.aem.toolkit.plugin.maven.TestConstants;
+
+public class MaxChildrenTestCases {
+    @AemComponent(
+        title = TestConstants.DEFAULT_COMPONENT_TITLE,
+        path = TestConstants.DEFAULT_COMPONENT_NAME
+    )
+    @MaxChildren(5)
+    public static class SimpleMaxLimitAnnotation {
+    }
+
+    @AemComponent(
+        title = TestConstants.DEFAULT_COMPONENT_TITLE,
+        path = TestConstants.DEFAULT_COMPONENT_NAME
+    )
+    @AllowedChildren(
+        classes = {ComplexComponent1.class, ComplexComponent2.class},
+        pagePaths = {"page/Path1, page/Path2"},
+        mode = PolicyMergeMode.MERGE
+    )
+    @MaxChildren(1)
+    public static class AllowedChildrenWithMaxLimit {
+    }
+}

plugin/src/test/resources/handlers/common/maxChildren/simple/.content.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<jcr:root xmlns:jcr="http://www.jcp.org/jcr/1.0"
+          xmlns:cq="http://www.day.com/jcr/cq/1.0"
+          jcr:primaryType="cq:Component"
+          jcr:title="Test Component"/>

plugin/src/test/resources/handlers/common/maxChildren/simple/_cq_childEditConfig.xml

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<jcr:root xmlns:cq="http://www.day.com/jcr/cq/1.0"
+          xmlns:jcr="http://www.jcp.org/jcr/1.0"
+          jcr:primaryType="cq:EditConfig">
+    <cq:listeners jcr:primaryType="cq:EditListenersConfig"
+                  resolvemaxchildren="() => 5"/>
+</jcr:root>

plugin/src/test/resources/handlers/common/maxChildren/withAllowedChildren/.content.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<jcr:root xmlns:jcr="http://www.jcp.org/jcr/1.0"
+          xmlns:cq="http://www.day.com/jcr/cq/1.0"
+          jcr:primaryType="cq:Component"
+          jcr:title="Test Component"/>

plugin/src/test/resources/handlers/common/maxChildren/withAllowedChildren/_cq_childEditConfig.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<jcr:root xmlns:cq="http://www.day.com/jcr/cq/1.0"
+          xmlns:jcr="http://www.jcp.org/jcr/1.0"
+          jcr:primaryType="cq:EditConfig">
+    <cq:listeners jcr:primaryType="cq:EditListenersConfig"
+                  resolvemaxchildren="() => 1"
+                  updatecomponentlist="Granite.PolicyResolver.build('{&quot;isEditConfig&quot;:false,&quot;rules&quot;:[{&quot;value&quot;:[&quot;/apps/eak/test-component&quot;],&quot;pagePaths&quot;:[&quot;page/Path1&quot;,&quot;page/Path2&quot;],&quot;mode&quot;:&quot;MERGE&quot;}]}')"/>
+</jcr:root>

ui.apps/src/main/content/jcr_root/apps/etoolbox-authoring-kit/clientlib-injector/.content.xml

@@ -3,5 +3,5 @@
 		  xmlns:jcr="http://www.jcp.org/jcr/1.0"
           jcr:primaryType="cq:ClientLibraryFolder"
           categories="[cq.authoring.dialog]"
-          dependencies="[eak.dependson,eak.coral-overlay,eak.lists.item-dialog,eak.policy-management]"
+          dependencies="[eak.dependson,eak.coral-overlay,eak.lists.item-dialog,eak.policies]"
 />

ui.apps/src/main/content/jcr_root/apps/etoolbox-authoring-kit/depends-on/.content.xml

@@ -3,6 +3,6 @@
 		  xmlns:jcr="http://www.jcp.org/jcr/1.0"
           jcr:primaryType="cq:ClientLibraryFolder"
           categories="[cq.authoring.dependson,eak.dependson]"
-          dependencies="[granite.jquery,granite.utils]"
+          dependencies="[eak.utils]"
 		  jsProcessor="[min:gcc;languageIn=ECMASCRIPT_2015,compilationLevel=advanced,languageOut=ECMASCRIPT5]"
 />

ui.apps/src/main/content/jcr_root/apps/etoolbox-authoring-kit/policy-management/.content.xml → ui.apps/src/main/content/jcr_root/apps/etoolbox-authoring-kit/policies/.content.xml

@@ -1,6 +1,8 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<jcr:root xmlns:cq="http://www.day.com/jcr/cq/1.0" xmlns:jcr="http://www.jcp.org/jcr/1.0"
+<jcr:root xmlns:cq="http://www.day.com/jcr/cq/1.0"
+		  xmlns:jcr="http://www.jcp.org/jcr/1.0"
           jcr:primaryType="cq:ClientLibraryFolder"
-          categories="[eak.policy-management]"
+          categories="[eak.policies]"
+          dependencies="[eak.utils]"
           jsProcessor="[min:gcc;languageIn=ECMASCRIPT_2015,compilationLevel=advanced,languageOut=ECMASCRIPT5]"
 />

ui.apps/src/main/content/jcr_root/apps/etoolbox-authoring-kit/policies/css.txt

@@ -0,0 +1 @@
+css/maxChildren.css

ui.apps/src/main/content/jcr_root/apps/etoolbox-authoring-kit/policies/css/maxChildren.css

@@ -0,0 +1,15 @@
+/* Blocked text */
+.cq-Overlay--placeholder[data-max-children-marker]::before {
+    content: attr(data-max-children-marker);
+    color: #d24637;
+
+    /* Position fix */
+    line-height: 100%;
+    vertical-align: middle;
+}
+
+/* Blocked hover state */
+.cq-Overlay--placeholder[data-max-children-marker]:hover {
+    border-color: #d24637;
+    background-color: rgba(203, 156, 150, 0.6);
+}

ui.apps/src/main/content/jcr_root/apps/etoolbox-authoring-kit/policies/js.txt

@@ -0,0 +1,3 @@
+js/policyUtils.js
+js/maxChildren.js
+js/policyManagement.js