001/*
002 * Copyright 2012-2018 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.boot.context.properties.bind.validation;
018
019import java.util.Arrays;
020import java.util.Deque;
021import java.util.LinkedHashSet;
022import java.util.LinkedList;
023import java.util.Set;
024import java.util.stream.Collectors;
025
026import org.springframework.boot.context.properties.bind.AbstractBindHandler;
027import org.springframework.boot.context.properties.bind.BindContext;
028import org.springframework.boot.context.properties.bind.BindHandler;
029import org.springframework.boot.context.properties.bind.Bindable;
030import org.springframework.boot.context.properties.source.ConfigurationProperty;
031import org.springframework.boot.context.properties.source.ConfigurationPropertyName;
032import org.springframework.validation.BeanPropertyBindingResult;
033import org.springframework.validation.BindingResult;
034import org.springframework.validation.Validator;
035
036/**
037 * {@link BindHandler} to apply {@link Validator Validators} to bound results.
038 *
039 * @author Phillip Webb
040 * @author Madhura Bhave
041 * @since 2.0.0
042 */
043public class ValidationBindHandler extends AbstractBindHandler {
044
045        private final Validator[] validators;
046
047        private final Set<ConfigurationProperty> boundProperties = new LinkedHashSet<>();
048
049        private final Deque<BindValidationException> exceptions = new LinkedList<>();
050
051        public ValidationBindHandler(Validator... validators) {
052                this.validators = validators;
053        }
054
055        public ValidationBindHandler(BindHandler parent, Validator... validators) {
056                super(parent);
057                this.validators = validators;
058        }
059
060        @Override
061        public Object onSuccess(ConfigurationPropertyName name, Bindable<?> target,
062                        BindContext context, Object result) {
063                if (context.getConfigurationProperty() != null) {
064                        this.boundProperties.add(context.getConfigurationProperty());
065                }
066                return super.onSuccess(name, target, context, result);
067        }
068
069        @Override
070        public void onFinish(ConfigurationPropertyName name, Bindable<?> target,
071                        BindContext context, Object result) throws Exception {
072                validate(name, target, context, result);
073                if (context.getDepth() == 0 && !this.exceptions.isEmpty()) {
074                        throw this.exceptions.pop();
075                }
076                super.onFinish(name, target, context, result);
077        }
078
079        private void validate(ConfigurationPropertyName name, Bindable<?> target,
080                        BindContext context, Object result) {
081                Object validationTarget = getValidationTarget(target, context, result);
082                Class<?> validationType = target.getBoxedType().resolve();
083                validate(name, validationTarget, validationType);
084        }
085
086        private Object getValidationTarget(Bindable<?> target, BindContext context,
087                        Object result) {
088                if (result != null) {
089                        return result;
090                }
091                if (context.getDepth() == 0 && target.getValue() != null) {
092                        return target.getValue().get();
093                }
094                return null;
095        }
096
097        private void validate(ConfigurationPropertyName name, Object target, Class<?> type) {
098                if (target != null) {
099                        BindingResult errors = new BeanPropertyBindingResult(target, name.toString());
100                        Arrays.stream(this.validators).filter((validator) -> validator.supports(type))
101                                        .forEach((validator) -> validator.validate(target, errors));
102                        if (errors.hasErrors()) {
103                                this.exceptions.push(getBindValidationException(name, errors));
104                        }
105                }
106        }
107
108        private BindValidationException getBindValidationException(
109                        ConfigurationPropertyName name, BindingResult errors) {
110                Set<ConfigurationProperty> boundProperties = this.boundProperties.stream()
111                                .filter((property) -> name.isAncestorOf(property.getName()))
112                                .collect(Collectors.toCollection(LinkedHashSet::new));
113                ValidationErrors validationErrors = new ValidationErrors(name, boundProperties,
114                                errors.getAllErrors());
115                return new BindValidationException(validationErrors);
116        }
117
118}