Initial implementations for customizing OutputContext

Introduce OutputContextCustomizer, TemplateVariableBindingCustomizer, WebOutputContextInitializer

grails-taglib/src/main/groovy/org/grails/taglib/TemplateVariableBindingCustomizer.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2022-2023 the original author or authors.
+ *
+ * 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
+ *
+ *      https://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 org.grails.taglib;
+
+/**
+ * Callback interface that can be used to customize a {@link AbstractTemplateVariableBinding}.
+ *
+ * @author Michael Yan
+ * @since 2022.0.0
+ * @see AbstractTemplateVariableBinding
+ */
+public interface TemplateVariableBindingCustomizer {
+
+    /**
+     * Callback to customize a {@link AbstractTemplateVariableBinding} instance.
+     * @param binding the Output Context to customize
+     */
+    void customize(AbstractTemplateVariableBinding binding);
+
+}

grails-taglib/src/main/groovy/org/grails/taglib/encoder/AbstractOutputContext.java

@@ -0,0 +1,58 @@
+/*
+ * Copyright 2022-2023 the original author or authors.
+ *
+ * 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
+ *
+ *      https://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 org.grails.taglib.encoder;
+
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.LinkedHashSet;
+import java.util.Set;
+
+import org.springframework.util.Assert;
+
+import org.grails.taglib.AbstractTemplateVariableBinding;
+import org.grails.taglib.TemplateVariableBindingCustomizer;
+
+/**
+ * Abstract {@link OutputContext} to support customizing
+ *
+ * @author Michael Yan
+ * @since 2022.0.0
+ * @see TemplateVariableBindingCustomizer
+ */
+public abstract class AbstractOutputContext implements OutputContext {
+
+    protected Set<TemplateVariableBindingCustomizer> variableBindingCustomizers = new LinkedHashSet<>();
+
+    public void addVariableBindingCustomizer(TemplateVariableBindingCustomizer... customizers) {
+        Assert.notNull(customizers, "Customizers must not be null");
+        this.variableBindingCustomizers.addAll(Arrays.asList(customizers));
+    }
+
+    public void setVariableBindingCustomizers(Collection<? extends TemplateVariableBindingCustomizer> customizers) {
+        Assert.notNull(customizers, "Customizers must not be null");
+        this.variableBindingCustomizers = new LinkedHashSet<>(customizers);
+    }
+
+    public Collection<TemplateVariableBindingCustomizer> getVariableBindingCustomizers() {
+        return this.variableBindingCustomizers;
+    }
+
+    protected void customizeTemplateVariableBinding(AbstractTemplateVariableBinding binding) {
+        for (TemplateVariableBindingCustomizer customizer : getVariableBindingCustomizers()) {
+            customizer.customize(binding);
+        }
+    }
+}

grails-taglib/src/main/groovy/org/grails/taglib/encoder/AbstractOutputContextLookup.java

@@ -0,0 +1,56 @@
+/*
+ * Copyright 2022-2023 the original author or authors.
+ *
+ * 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
+ *
+ *      https://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 org.grails.taglib.encoder;
+
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.LinkedHashSet;
+import java.util.Set;
+
+import org.springframework.util.Assert;
+
+/**
+ * Abstract {@link OutputContextLookup} to support customizing
+ *
+ * @author Michael Yan
+ * @since 2022.0.0
+ * @see OutputContextCustomizer
+ */
+public abstract class AbstractOutputContextLookup implements OutputContextLookup {
+
+    protected Set<OutputContextCustomizer> customizers = new LinkedHashSet<>();
+
+    public void addContextCustomizers(OutputContextCustomizer... customizers) {
+        Assert.notNull(customizers, "Customizers must not be null");
+        this.customizers.addAll(Arrays.asList(customizers));
+    }
+
+    public void setContextCustomizers(Collection<? extends OutputContextCustomizer> customizers) {
+        Assert.notNull(customizers, "Customizers must not be null");
+        this.customizers = new LinkedHashSet<>(customizers);
+    }
+
+    public Collection<OutputContextCustomizer> getContextCustomizers() {
+        return this.customizers;
+    }
+
+    protected void customizeOutputContext(OutputContext outputContext) {
+        for (OutputContextCustomizer customizer : getContextCustomizers()) {
+            customizer.customize(outputContext);
+        }
+    }
+
+}

grails-taglib/src/main/groovy/org/grails/taglib/encoder/DefaultOutputContext.java

@@ -0,0 +1,105 @@
+/*
+ * Copyright 2015-2023 the original author or authors.
+ *
+ * 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
+ *
+ *      https://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 org.grails.taglib.encoder;
+
+import java.io.Writer;
+
+import grails.core.GrailsApplication;
+import grails.util.Holders;
+
+import org.grails.encoder.DefaultEncodingStateRegistry;
+import org.grails.encoder.EncodingStateRegistry;
+import org.grails.taglib.AbstractTemplateVariableBinding;
+import org.grails.taglib.TemplateVariableBinding;
+
+/**
+ * Default implementation for {@link OutputContext}
+ *
+ * @author Lari Hotari
+ * @since 3.0
+ */
+public class DefaultOutputContext extends AbstractOutputContext {
+
+    private OutputEncodingStack outputEncodingStack;
+
+    private Writer currentWriter;
+
+    private AbstractTemplateVariableBinding binding;
+
+    private EncodingStateRegistry encodingStateRegistry = new DefaultEncodingStateRegistry();
+
+    public DefaultOutputContext() {
+
+    }
+
+    @Override
+    public EncodingStateRegistry getEncodingStateRegistry() {
+        return this.encodingStateRegistry;
+    }
+
+    @Override
+    public void setCurrentOutputEncodingStack(OutputEncodingStack outputEncodingStack) {
+        this.outputEncodingStack = outputEncodingStack;
+    }
+
+    @Override
+    public OutputEncodingStack getCurrentOutputEncodingStack() {
+        return this.outputEncodingStack;
+    }
+
+    @Override
+    public Writer getCurrentWriter() {
+        return this.currentWriter;
+    }
+
+    @Override
+    public void setCurrentWriter(Writer currentWriter) {
+        this.currentWriter = currentWriter;
+    }
+
+    @Override
+    public AbstractTemplateVariableBinding createAndRegisterRootBinding() {
+        this.binding = new TemplateVariableBinding();
+        customizeTemplateVariableBinding(this.binding);
+        return this.binding;
+    }
+
+    @Override
+    public AbstractTemplateVariableBinding getBinding() {
+        return this.binding;
+    }
+
+    @Override
+    public void setBinding(AbstractTemplateVariableBinding binding) {
+        this.binding = binding;
+    }
+
+    @Override
+    public GrailsApplication getGrailsApplication() {
+        return Holders.findApplication();
+    }
+
+    @Override
+    public void setContentType(String contentType) {
+        // no-op
+    }
+
+    @Override
+    public boolean isContentTypeAlreadySet() {
+        return true;
+    }
+
+}

grails-taglib/src/main/groovy/org/grails/taglib/encoder/DefaultOutputContextLookup.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015-2022 the original author or authors.
+ * Copyright 2015-2023 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,21 +15,19 @@
  */
 package org.grails.taglib.encoder;
 
-import java.io.Writer;
-
 import org.springframework.core.Ordered;
 
-import grails.core.GrailsApplication;
-import grails.util.Holders;
-
-import org.grails.encoder.DefaultEncodingStateRegistry;
 import org.grails.encoder.EncodingStateRegistry;
 import org.grails.encoder.EncodingStateRegistryLookup;
 import org.grails.encoder.EncodingStateRegistryLookupHolder;
-import org.grails.taglib.AbstractTemplateVariableBinding;
-import org.grails.taglib.TemplateVariableBinding;
 
-public class DefaultOutputContextLookup implements OutputContextLookup, EncodingStateRegistryLookup, Ordered {
+/**
+ * Default implementation for {@link OutputContextLookup}
+ *
+ * @author Lari Hotari
+ * @since 3.0
+ */
+public class DefaultOutputContextLookup extends AbstractOutputContextLookup implements EncodingStateRegistryLookup, Ordered {
 
     private ThreadLocal<OutputContext> outputContextThreadLocal = new ThreadLocal<OutputContext>() {
         @Override
@@ -38,13 +36,19 @@ protected OutputContext initialValue() {
         }
     };
 
+    public DefaultOutputContextLookup() {
+
+    }
+
     @Override
     public OutputContext lookupOutputContext() {
         if (EncodingStateRegistryLookupHolder.getEncodingStateRegistryLookup() == null) {
             // TODO: improve EncodingStateRegistry solution so that global state doesn't have to be used
             EncodingStateRegistryLookupHolder.setEncodingStateRegistryLookup(this);
         }
-        return this.outputContextThreadLocal.get();
+        OutputContext outputContext = this.outputContextThreadLocal.get();
+        customizeOutputContext(outputContext);
+        return outputContext;
     }
 
     @Override
@@ -57,80 +61,4 @@ public EncodingStateRegistry lookup() {
         return lookupOutputContext().getEncodingStateRegistry();
     }
 
-    public DefaultOutputContextLookup() {
-
-    }
-
-    public static class DefaultOutputContext implements OutputContext {
-
-        private OutputEncodingStack outputEncodingStack;
-
-        private Writer currentWriter;
-
-        private AbstractTemplateVariableBinding binding;
-
-        private EncodingStateRegistry encodingStateRegistry = new DefaultEncodingStateRegistry();
-
-        public DefaultOutputContext() {
-
-        }
-
-        @Override
-        public EncodingStateRegistry getEncodingStateRegistry() {
-            return this.encodingStateRegistry;
-        }
-
-        @Override
-        public void setCurrentOutputEncodingStack(OutputEncodingStack outputEncodingStack) {
-            this.outputEncodingStack = outputEncodingStack;
-        }
-
-        @Override
-        public OutputEncodingStack getCurrentOutputEncodingStack() {
-            return this.outputEncodingStack;
-        }
-
-        @Override
-        public Writer getCurrentWriter() {
-            return this.currentWriter;
-        }
-
-        @Override
-        public void setCurrentWriter(Writer currentWriter) {
-            this.currentWriter = currentWriter;
-        }
-
-        @Override
-        public AbstractTemplateVariableBinding createAndRegisterRootBinding() {
-            this.binding = new TemplateVariableBinding();
-            return this.binding;
-        }
-
-        @Override
-        public AbstractTemplateVariableBinding getBinding() {
-            return this.binding;
-        }
-
-        @Override
-        public void setBinding(AbstractTemplateVariableBinding binding) {
-            this.binding = binding;
-        }
-
-        @Override
-        public GrailsApplication getGrailsApplication() {
-            return Holders.findApplication();
-        }
-
-        @Override
-        public void setContentType(String contentType) {
-            // no-op
-        }
-
-        @Override
-        public boolean isContentTypeAlreadySet() {
-            return true;
-        }
-
-    }
-
 }