Integrated standard Spring MessageSource components for resolving error messages in validators.

spring-data-rest-webmvc/src/main/java/org/springframework/data/rest/webmvc/RepositoryRestController.java

@@ -22,6 +22,8 @@ import java.util.SortedSet;
 import java.util.TreeSet;
 import java.util.concurrent.atomic.AtomicReference;
 import javax.servlet.http.HttpServletRequest;
+import javax.validation.ConstraintViolation;
+import javax.validation.ConstraintViolationException;
 
 import org.codehaus.jackson.map.ObjectMapper;
 import org.slf4j.Logger;
@@ -1579,7 +1581,46 @@ public class RepositoryRestController
     Map m = new HashMap();
     List<String> errors = new ArrayList<String>();
     for(FieldError fe : ex.getErrors().getFieldErrors()) {
-      errors.add(fe.getDefaultMessage());
+      String msg = applicationContext.getMessage(fe.getCode(),
+                                                 new Object[]{fe.getObjectName(), fe.getField(), fe.getRejectedValue()},
+                                                 fe.getDefaultMessage(),
+                                                 null);
+      errors.add(msg);
+    }
+    m.put("errors", errors);
+
+    return negotiateResponse(request, HttpStatus.BAD_REQUEST, new HttpHeaders(), m);
+  }
+
+  /**
+   * Send a 400 Bad Request in case of a validation failure.
+   *
+   * @param ex
+   * @param request
+   *
+   * @return
+   *
+   * @throws IOException
+   */
+  @SuppressWarnings({"unchecked"})
+  @ExceptionHandler(ConstraintViolationException.class)
+  @ResponseBody
+  public ResponseEntity handleJsr303ValidationFailure(ConstraintViolationException ex,
+                                                      ServletServerHttpRequest request) throws IOException {
+    LOG.error(ex.getMessage(), ex);
+
+    Map m = new HashMap();
+    List<String> errors = new ArrayList<String>();
+    for(ConstraintViolation cv : ex.getConstraintViolations()) {
+      String msg = applicationContext.getMessage(cv.getMessageTemplate(),
+                                                 new Object[]{
+                                                     cv.getLeafBean().getClass().getSimpleName(),
+                                                     cv.getPropertyPath().toString(),
+                                                     cv.getInvalidValue()
+                                                 },
+                                                 cv.getMessage(),
+                                                 null);
+      errors.add(msg);
     }
     m.put("errors", errors);
 

spring-data-rest-webmvc/src/test/groovy/org/springframework/data/rest/webmvc/spec/EventsSpec.groovy

@@ -2,10 +2,13 @@ package org.springframework.data.rest.webmvc.spec
 
 import org.springframework.beans.factory.annotation.Autowired
 import org.springframework.data.rest.repository.RepositoryConstraintViolationException
+import org.springframework.data.rest.test.webmvc.Customer
 import org.springframework.data.rest.test.webmvc.Person
 import org.springframework.data.rest.test.webmvc.TestRepositoryEventListener
 import org.springframework.http.HttpStatus
 
+import javax.validation.ConstraintViolationException
+
 /**
  * @author Jon Brisbin
  */
@@ -20,13 +23,37 @@ class EventsSpec extends BaseSpec {
     def request = createJsonRequest("POST", "people", null, person)
 
     when:
-    controller.create(request, baseUri, "people")
+    try {
+      controller.create(request, baseUri, "people")
+    } catch (RepositoryConstraintViolationException e) {
+      controller.handleValidationFailure(e, request)
+      throw e
+    }
 
     then:
     thrown(RepositoryConstraintViolationException)
 
   }
 
+  def "handles JSR-303 validation errors"() {
+
+    given:
+    def cust = new Customer()
+    def request = createJsonRequest("POST", "customer", null, cust)
+
+    when:
+    try {
+      controller.create(request, baseUri, "customer")
+    } catch (ConstraintViolationException e) {
+      controller.handleJsr303ValidationFailure(e, request)
+      throw e
+    }
+
+    then:
+    thrown(ConstraintViolationException)
+
+  }
+
   def "captures before and after events"() {
 
     given:

spring-data-rest-webmvc/src/test/java/org/springframework/data/rest/test/ApplicationConfig.java

@@ -1,33 +1,14 @@
 package org.springframework.data.rest.test;
 
-import java.io.IOException;
-import java.sql.Timestamp;
-import java.text.SimpleDateFormat;
-import java.util.ArrayList;
-import java.util.List;
 import javax.persistence.EntityManagerFactory;
 import javax.sql.DataSource;
 
-import org.codehaus.jackson.JsonGenerationException;
-import org.codehaus.jackson.JsonGenerator;
-import org.codehaus.jackson.Version;
-import org.codehaus.jackson.map.Module;
-import org.codehaus.jackson.map.SerializerProvider;
-import org.codehaus.jackson.map.module.SimpleSerializers;
-import org.codehaus.jackson.map.ser.std.SerializerBase;
+import org.springframework.context.MessageSource;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.ComponentScan;
 import org.springframework.context.annotation.Configuration;
-import org.springframework.core.convert.ConversionService;
-import org.springframework.core.convert.converter.Converter;
+import org.springframework.context.support.ResourceBundleMessageSource;
 import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
-import org.springframework.data.rest.test.webmvc.Person;
-import org.springframework.data.rest.test.webmvc.PersonValidator;
-import org.springframework.data.rest.test.webmvc.TestRepositoryEventListener;
-import org.springframework.format.support.DefaultFormattingConversionService;
-import org.springframework.hateoas.Link;
-import org.springframework.hateoas.Resource;
-import org.springframework.hateoas.ResourceProcessor;
 import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseBuilder;
 import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseType;
 import org.springframework.orm.jpa.JpaDialect;
@@ -48,6 +29,12 @@ import org.springframework.transaction.annotation.EnableTransactionManagement;
 @EnableTransactionManagement
 public class ApplicationConfig {
 
+  @Bean public MessageSource messageSource() {
+    ResourceBundleMessageSource ms = new ResourceBundleMessageSource();
+    ms.setBasename("org.springframework.data.rest.test.ValidationErrors");
+    return ms;
+  }
+
   @Bean public DataSource dataSource() {
     EmbeddedDatabaseBuilder builder = new EmbeddedDatabaseBuilder();
     return builder.setType(EmbeddedDatabaseType.HSQL).build();

spring-data-rest-webmvc/src/test/java/org/springframework/data/rest/test/webmvc/Customer.java

@@ -3,6 +3,7 @@ package org.springframework.data.rest.test.webmvc;
 import javax.persistence.Entity;
 import javax.persistence.GeneratedValue;
 import javax.persistence.Id;
+import javax.validation.constraints.NotNull;
 
 /**
  * @author Jon Brisbin
@@ -11,6 +12,7 @@ import javax.persistence.Id;
 public class Customer {
 
   @Id @GeneratedValue private Long   id;
+  @NotNull
   private                     String userid;
 
   public Long getId() {

spring-data-rest-webmvc/src/test/java/org/springframework/data/rest/test/webmvc/PersonValidator.java

@@ -21,7 +21,7 @@ public class PersonValidator implements Validator {
   @Override public void validate(Object target, Errors errors) {
     Person p = (Person)target;
     LOG.debug(" ***** Validating Person " + p);
-    ValidationUtils.rejectIfEmpty(errors, "name", "field.name.required", "Field 'name' cannot be blank.");
+    ValidationUtils.rejectIfEmpty(errors, "name", "field.name.required");
   }
 
 }