experimental/branch_for_jsf_2/validation-modules/bean-validation/src/main/java/org/apache/myfaces/extensions/validator/beanval/BeanValidationInterceptor.java

/*
 * 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.
 */
package org.apache.myfaces.extensions.validator.beanval;

import org.apache.myfaces.extensions.validator.core.renderkit.exception.SkipBeforeInterceptorsException;
import org.apache.myfaces.extensions.validator.core.renderkit.exception.SkipRendererDelegationException;
import org.apache.myfaces.extensions.validator.core.recorder.ProcessedInformationRecorder;
import org.apache.myfaces.extensions.validator.core.ExtValContext;
import org.apache.myfaces.extensions.validator.core.WebXmlParameter;
import org.apache.myfaces.extensions.validator.core.validation.strategy.ValidationStrategy;
import org.apache.myfaces.extensions.validator.core.property.PropertyInformation;
import org.apache.myfaces.extensions.validator.core.property.PropertyInformationKeys;
import org.apache.myfaces.extensions.validator.core.property.PropertyDetails;
import org.apache.myfaces.extensions.validator.core.metadata.extractor.MetaDataExtractor;
import org.apache.myfaces.extensions.validator.core.metadata.MetaDataEntry;
import org.apache.myfaces.extensions.validator.core.metadata.transformer.MetaDataTransformer;
import org.apache.myfaces.extensions.validator.core.interceptor.AbstractRendererInterceptor;
import org.apache.myfaces.extensions.validator.util.ExtValUtils;
import org.apache.myfaces.extensions.validator.beanval.property.BeanValidationPropertyInformationKeys;
import org.apache.myfaces.extensions.validator.beanval.validation.strategy.BeanValidationStrategyAdapter;
import org.apache.myfaces.extensions.validator.internal.ToDo;
import org.apache.myfaces.extensions.validator.internal.Priority;
import org.apache.myfaces.extensions.validator.internal.UsageInformation;
import org.apache.myfaces.extensions.validator.internal.UsageCategory;

import javax.faces.context.FacesContext;
import javax.faces.component.UIComponent;
import javax.faces.component.EditableValueHolder;
import javax.faces.render.Renderer;
import javax.faces.convert.ConverterException;
import javax.faces.validator.ValidatorException;
import javax.faces.application.FacesMessage;
import javax.validation.Validation;
import javax.validation.BeanDescriptor;
import javax.validation.ElementDescriptor;
import javax.validation.ConstraintDescriptor;
import javax.validation.ValidatorFactory;
import javax.validation.ConstraintViolation;
import java.util.Set;
import java.util.Map;
import java.io.IOException;

/**
 * @author Gerhard Petracek
 * @since x.x.3
 */
@ToDo(value = Priority.HIGH, description = "sync jsf 2.0 specific changes with bv-branch")
@UsageInformation(UsageCategory.INTERNAL)
public class BeanValidationInterceptor extends AbstractRendererInterceptor
{
    private ValidatorFactory validationFactory = Validation.buildDefaultValidatorFactory();

    @Override
    public void beforeEncodeBegin(FacesContext facesContext, UIComponent uiComponent, Renderer wrapped)
            throws IOException, SkipBeforeInterceptorsException, SkipRendererDelegationException
    {
        if(processComponent(uiComponent))
        {
            initComponent(facesContext, uiComponent);
        }
    }

    @ToDo(value = Priority.HIGH, description = "check groups")
    protected void initComponent(FacesContext facesContext, UIComponent uiComponent)
    {
        if (logger.isTraceEnabled())
        {
            logger.trace("start to init component " + uiComponent.getClass().getName());
        }

        MetaDataExtractor metaDataExtractor = ExtValUtils.getComponentMetaDataExtractor();

        PropertyDetails propertyDetails = metaDataExtractor.extract(facesContext, uiComponent)
                .getInformation(PropertyInformationKeys.PROPERTY_DETAILS, PropertyDetails.class);

        if(propertyDetails.getBaseObject() == null)
        {
            if(this.logger.isWarnEnabled())
            {
                this.logger.warn("no base object at " + propertyDetails.getKey() +
                        " component-id: " + uiComponent.getClientId(facesContext));
            }
            return;
        }

        /*TODO
            //TODO extract groups - see ValidationGroupProvider
            Class[] foundGroups = ExtValBeanValidationContext.getCurrentInstance().getGroups(
                    facesContext.getViewRoot().getViewId(),
                    uiComponent.getClientId(facesContext));

            foundGroups = mergeFoundGroupsWithValidatorGroups(
                foundGroups, ((EditableValueHolder)uiComponent).getValidators());
         */

        BeanDescriptor beanDescriptor = this.validationFactory.getValidator().getConstraintsForClass(
                propertyDetails.getBaseObject().getClass()/*, foundGroups*/);

        ElementDescriptor elementDescriptor = beanDescriptor.getConstraintsForProperty(propertyDetails.getProperty());

        if(elementDescriptor == null)
        {
            return;
        }
        
        ValidationStrategy validationStrategy;
        MetaDataTransformer metaDataTransformer;
        MetaDataEntry entry;
        Map<String, Object> metaData;

        for (ConstraintDescriptor<?> constraintDescriptor : elementDescriptor.getConstraintDescriptors())
        {
            //TODO check groups
            
            validationStrategy = new BeanValidationStrategyAdapter(constraintDescriptor);

            /*
             * per default
             * org.apache.myfaces.extensions.validator.beanval.metadata.transformer.BeanValidationMetaDataTransformer
             * is bound to BeanValidationStrategyAdapter
             * don't use it directly - it's possible to deactivate
             * org.apache.myfaces.extensions.validator.beanval.metadata.transformer.mapper
             *    .DefaultBeanValidationStrategyToMetaDataTransformerNameMapper
             */
            metaDataTransformer = ExtValUtils.getMetaDataTransformerForValidationStrategy(validationStrategy);

            if (metaDataTransformer != null)
            {
                if (this.logger.isDebugEnabled())
                {
                    this.logger.debug(metaDataTransformer.getClass().getName() + " instantiated");
                }

                entry = new MetaDataEntry();
                entry.setKey(constraintDescriptor.getAnnotation().annotationType().getName());
                entry.setValue(constraintDescriptor);
                //TODO (?) add type of property for meta-data transformation (e.g. size: string vs. number)

                metaData = metaDataTransformer.convertMetaData(entry);
            }
            else
            {
                metaData = null;
            }

            if (metaData == null)
            {
                continue;
            }

            //get component initializer for the current component and configure it
            //also in case of skipped validation to reset e.g. the required attribute
            if (!metaData.isEmpty())
            {
                ExtValUtils.configureComponentWithMetaData(facesContext, uiComponent, metaData);
            }
        }

        if (logger.isTraceEnabled())
        {
            logger.trace("init component of " + uiComponent.getClass().getName() + " finished");
        }
    }

    @Override
    public void beforeGetConvertedValue(FacesContext facesContext, UIComponent uiComponent, Object o, Renderer wrapped)
            throws ConverterException, SkipBeforeInterceptorsException, SkipRendererDelegationException
    {
        Object convertedObject = wrapped.getConvertedValue(facesContext, uiComponent, o);

        //recorde user input e.g. for cross-component validation
        for (ProcessedInformationRecorder recorder : ExtValContext.getContext().getProcessedInformationRecorders())
        {
            recorder.recordUserInput(uiComponent, convertedObject);

            if (logger.isTraceEnabled())
            {
                logger.trace(recorder.getClass().getName() + " called");
            }
        }

        try
        {
            if(processComponent(uiComponent))
            {
                processValidation(facesContext, uiComponent, convertedObject);
            }
        }
        catch (ValidatorException e)
        {
            throw new ConverterException(e.getFacesMessage(), e);
        }
    }

    protected boolean processComponent(UIComponent uiComponent)
    {
        return uiComponent instanceof EditableValueHolder;
    }

    @ToDo(value = Priority.HIGH, description = "use ExtValUtils#createFacesMessage")
    protected void processValidation(FacesContext facesContext, UIComponent uiComponent, Object convertedObject)
    {
        if (!"true".equalsIgnoreCase(WebXmlParameter.DEACTIVATE_EMPTY_STRING_INTERPRETATION)
                && "".equals(convertedObject))
        {
            convertedObject = null;
        }

        MetaDataExtractor metaDataExtractor = ExtValUtils.getComponentMetaDataExtractor();

        PropertyInformation propertyInformation = metaDataExtractor.extract(facesContext, uiComponent);

        //e.g.: extract groups for validation
        if(!ExtValUtils.executeBeforeValidationInterceptors(facesContext, uiComponent, convertedObject,
                PropertyInformation.class.getName() ,propertyInformation))
        {
            return;
        }

        try
        {
            if (logger.isTraceEnabled())
            {
                logger.trace("jsr303 start validation");
            }

            processFieldValidation(facesContext, uiComponent, convertedObject, propertyInformation);

            if (logger.isTraceEnabled())
            {
                logger.trace("jsr303 validation finished");
            }
        }
        finally
        {
            ExtValUtils.executeAfterValidationInterceptors(facesContext, uiComponent, convertedObject,
                    PropertyInformation.class.getName(), propertyInformation);
        }
    }

    protected void processFieldValidation(FacesContext facesContext,
                                        UIComponent uiComponent,
                                        Object convertedObject,
                                        PropertyInformation propertyInformation)
    {
        Class baseBeanClass = (propertyInformation.getInformation(
                PropertyInformationKeys.PROPERTY_DETAILS, PropertyDetails.class)).getBaseObject().getClass();

        String propertyName = (propertyInformation.getInformation(
                PropertyInformationKeys.PROPERTY_DETAILS, PropertyDetails.class)).getProperty();

        ExtValBeanValidationContext beanValidationContext = ExtValBeanValidationContext.getCurrentInstance();

        Class[] groups = beanValidationContext.getGroups(
                facesContext.getViewRoot().getViewId(), uiComponent.getClientId(facesContext));

        if(groups == null)
        {
            return;
        }

        Set<ConstraintViolation> violations = this.validationFactory.usingContext()
                .messageInterpolator(ExtValBeanValidationContext.getCurrentInstance().getMessageInterpolator())
                .getValidator()
                .validateValue(baseBeanClass, propertyName, convertedObject, groups);

        if (violations != null && violations.size() > 0)
        {
            //TODO jsf 2.0 supports multiple messages -> use all messages
            ConstraintViolation violation = (ConstraintViolation) violations.toArray()[0];

            String violationMessage = violation.getMessage();

            String labeledMessage = "{0}: " + violationMessage;
            ValidatorException validatorException = new ValidatorException(
                    new FacesMessage(FacesMessage.SEVERITY_ERROR, labeledMessage, labeledMessage));

            ExtValUtils.executeAfterThrowingInterceptors(
                    uiComponent,
                    null,
                    convertedObject,
                    validatorException,
                    null);

            //TODO check & remove
            propertyInformation.setInformation(
                    BeanValidationPropertyInformationKeys.CONSTRAINT_VIOLATIONS, violations);

            if (labeledMessage.equals(validatorException.getFacesMessage().getSummary()) ||
                    labeledMessage.equals(validatorException.getFacesMessage().getDetail()))
            {
                throw new ValidatorException(
                        new FacesMessage(FacesMessage.SEVERITY_ERROR, violationMessage, violationMessage));
            }
            else
            {
                throw validatorException;
            }
        }
    }
    
}