I'm working on a project using Spring 3.1. We're doing all our validation server side but are running into an issue when a request parameter is bound to a Long or Integer object. While most invalid values ultimately result in an exception and an error message is displayed, this is not the case when the request parameter contains whitespace between digits. For example, when binding "12345 6789", we would expect a validation error but instead the whitespace is just getting trimmed out.
I've used the debugger to find that this is occurring in org.springframework.util.NumberUtils. A StringUtils.trimAllWhitespace is called to remove the whitespace from all input. This seems like a common enough use-case but I've so far been unable to find anyone who has a good solution. What would be the best way to do a simple conversion of the String on the request parameters to Long or Integer while only accepting digits?
A solution would be to create a custom validator that will meet your needs.
Example taken from the documentation:
Constraint declaration:
#Target({ElementType.METHOD, ElementType.FIELD})
#Retention(RetentionPolicy.RUNTIME)
#Constraint(validatedBy=MyConstraintValidator.class)
public #interface MyConstraint {
}
Constraint implementation
import javax.validation.ConstraintValidator;
public class MyConstraintValidator implements ConstraintValidator {
#Autowired;
private Foo aDependency;
...
}
Edit:
Creating a custom property converter documentation.
#Controller
public class MyFormController {
#InitBinder
public void initBinder(WebDataBinder binder) {
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
dateFormat.setLenient(false);
binder.registerCustomEditor(Date.class, new CustomDateEditor(dateFormat, false));
}
// ...
}
Related
I have a field in my entity that holds phone-number. According to the conventions of the project, I need to save it in E.164 format in the DB. At the moment I use #PrePersist and #PreUpdate annotations for changing the phone number to the specified format. This method is good for one or two entities but it becomes very error-prone when you have to repeat it over and over.
I was thinking that it would be awesome if I could put the code in annotation and the annotation reads the fields and changes its value just before the persistence something like what #LastModifiedDate and annotation do. I searched the web for the codes of this annotation but I didn't understand how they managed it.
How I can write an annotation that reads the value of a field and changes it before persistence, and how I can do it before some specific operations like delete (I want to set some params before deleting the object too)
Take a look at EntityListeners.
You can create a listener that checks your custom annotation and triggers the appropriate methods.
#Retention(RetentionPolicy.RUNTIME)
#Target(ElementType.FIELD)
public #interface TheCustomAnnotation{
}
#Entity
#EntityListeners(TheListener.class)
public class TheEntity {
#TheCustomAnnotation
private String phoneNumber;
public class TheListener {
#PrePersist
public void prePersist(Object target) {
for(Field field : target.getClass().getDeclaredFields()){
Annotation[] annotations = field.getDeclaredAnnotations();
// Iterate annotations and check if yours is in it.
}
}
This is just an example.
#Pattern is a pretty powerful annotation that would be a good fit for validations if you are experienced with regular expressions.
For example,
#Pattern(regexp="^[0-9]{3}-[0-9]{3}-[0-9]{4}$")
private String phoneNumber;
The downside is that this only works for Strings though.
If you are interested more in conversions than validations, you may want to look into #JsonDeserialize if you are using Jackson.
For example:
#JsonDeserialize(using=PhoneNumberDeserializer.class)
private String phoneNumber;
Pattern phonePattern = Pattern.compile("^[0-9]{3}(.+)[0-9]{3}(.+)[0-9]{4}$");
public class PhoneNumberDeserializer extends JsonDeserializer<String> {
#Override
public String deserialize(JsonParser jsonParser,
DeserializationContext deserializationContext)
throws IOException, JsonProcessingException {
String phone = jsonParser.getText();
if (matcher.matches(phone)) {
Matcher matcher = phonePattern.matcher(phone);
for (int i = 1; i < matcher.groupCount(); i++) {
marcher.group(i).replaceAll(".*", "");
}
}
}
}
This will work for any type, not just strings.
Sorry it's a little convoluted, I was having fun reteaching myself.
According to the current doc (5.0.0.RELEASE) Spring Webflux supports validation when working with annotated controllers:
By default if Bean Validation is present on the classpath — e.g.
Hibernate Validator, the LocalValidatorFactoryBean is registered as a
global Validator for use with #Valid and Validated on #Controller
method arguments.
However nothing is said about how to automate it with functional endpoints. In fact, the only example of input processing in the documentation doesn't validate anything:
public Mono<ServerResponse> createPerson(ServerRequest request) {
Mono<Person> person = request.bodyToMono(Person.class);
return ServerResponse.ok().build(repository.savePerson(person));
}
Are we supposed to do this manually or there is some automatic way to do it?
In Spring version 5.0, there is no automatic way to do validation in functional endpoints, and as such validation must be done manually.
Though there are currently no concrete plans to do so, we might add some sort of validation in the future. But even then it will be an explicit method call, and not an automatic mechanism. Overall, the functional endpoint model is designed to be a lot more explicit than the annotation-based model.
As arjen-poutsma said, it seems there is no way of running automated validations on Spring 5 functional endpoints.
Spring documentation is not very clear about this, and it doesn't suggest any approach.
On this Baeldung article, you'll find an idea on how you can run validations using this approach (disclaimer: I'm the writer of the article :) )
In a nutshell, you can follow these steps:
Implement Spring Validators to evaluate your resources
Create an abstract class with the basic procedure that any handler will follow when processing a request, leaving up to the children classes what to do when the data is valid
Make your request handler classes extend this abstract class, implementing this abstract method, stating the body it will be expecting, and what validator needs to be used to validate it
EDIT:
I've been following this related Spring issue, and it seems we now count with official documentation regarding this subject: https://github.com/spring-projects/spring-framework/blob/master/src/docs/asciidoc/web/webflux-functional.adoc#validation
The suggested approach is to use validators as explained in the article.
At the current version(2.0.4.RELEASE) there isn't a way to do automatic validation with handles, however you always could make a manual validation like this:
#Slf4j
#Component
#FieldDefaults(makeFinal = true, level = AccessLevel.PRIVATE)
#RequiredArgsConstructor
public class MyHandlerValidator implements HandlerValidator<MyResource> {
Validator validator;
#Override
public void callValidator(final MyResource fdr) {
final DataBinder binder = new DataBinder(fdr);
binder.setValidator(validator);
binder.validate();
if (binder.getBindingResult().hasErrors()) {
final String reason = binder.getBindingResult().getFieldError().toString();
log.error(reason);
throw new ResponseStatusException(HttpStatus.BAD_REQUEST, reason);
}
}
}
The thing with this, its that the you should throw a WebExchangeBindException like automatic validation does, however i could't create a MethodParameter witch is a dependency to create this exception.
UPDATE:
Spring show us a way to do it, which is similar to my solution, but, not enough in my opinion on documentation
Just to demo some working code. If you need simple validation based on the object annotations like:
#Value
#Builder
#Jacksonized
public class SigninRequest {
#NotBlank(message = "The username is mandatory")
#Email(message = "The username should be valid Email")
String username;
#NotBlank(message = "The password is mandatory")
String password;
}
At the handler you need just one simple additional operator doOnNext:
#Component
#RequiredArgsConstructor
public class AuthHandler {
private final AuthService authService;
private final ObjectValidator validator;
public Mono<ServerResponse> signin(ServerRequest request) {
return ok().body(
request.bodyToMono(SigninRequest.class)
.doOnNext(validator::validate) //<-- just one single line
.flatMap(login -> authService.authenticate(login.getUsername(), login.getPassword())),
AuthResult.class);
}
}
The ObjectValidator is doing actual validation and throws the runtime exception with the 4xx error in case of validation errors:
#Component
#RequiredArgsConstructor
public class ObjectValidator {
private final Validator validator;
public <T> T validate(T object) {
var errors = validator.validate(object);
if (errors.isEmpty()) {
return object;
} else {
String errorDetails = errors.stream().map(er -> er.getMessage()).collect(Collectors.joining(", "));
throw new ObjectValidationException(errorDetails);
}
}
}
And the exception:
#ResponseStatus(code = HttpStatus.UNPROCESSABLE_ENTITY)
public class ObjectValidationException extends RuntimeException {
public ObjectValidationException(String errorDetails) {
super("Please supply the valid data: " + errorDetails);
}
}
If you properly setup global error handling you can keep you handler code clean and reuse the object validator across all your handlers.
How can I use the #Value annotation to configure a Joda-Time Period field in my spring bean?
E.g. Given the following component class:
#Component
public class MyService {
#Value("${myapp.period:P1D}")
private Period periodField;
...
}
I want to use standard ISO8601 format to define the period in a properties file.
I get this error:
Caused by: java.lang.IllegalStateException: Cannot convert value of type [java.lang.String] to required type [org.joda.time.Period]: no matching editors or conversion strategy found
at org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:302)
at org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:125)
at org.springframework.beans.TypeConverterSupport.doConvert(TypeConverterSupport.java:61)
... 35 more
A simple solution that does not require any java code is to use Spring Expression Language (SpEL).
(My example uses java.time.Duration and not Joda stuff but I think you get it anyway.)
#Value("#{T(java.time.Duration).parse('${notifications.maxJobAge}')}")
private Duration maxJobAge;
What you can do is register a Spring ConversionService bean and implement a proper converter.
#Bean
public ConversionServiceFactoryBean conversionService() {
ConversionServiceFactoryBean conversionServiceFactoryBean = new ConversionServiceFactoryBean();
Set<Converter<?, ?>> myConverters = new HashSet<>();
myConverters.add(new StringToPeriodConverter());
conversionServiceFactoryBean.setConverters(myConverters);
return conversionServiceFactoryBean;
}
public class StringToPeriodConverter implements Converter<String, Period> {
#Override
public Period convert(String source) {
return Period.parse(source);
}
}
Another, not elegant, option, is to use a String setter who invokes the parse method.
#Value("${myapp.period:P1D}")
public void setPeriodField(String periodField)
{
if (isBlank(periodField))
this.periodField= null;
this.periodField= Duration.parse(periodField);
}
For joda-time:2.10.13 and spring-boot:2.3.2.RELEASE next example (like in question) is worked:
#Value("${myapp.period:P1D}")
private Period periodField;
If you use java.time.Period, in addition, worked a simple period property format (org.springframework.boot.convert.PeriodStyle):
#Value("${myapp.period:1d}")
private Period periodField;
I have a really strange issue with converting from domain objects to those Neo4j can natively store as property value. As a test case I use Joda's DateTime. A object of that type can be converted to a String or Long quite easily.
The conversion from DateTime to String works flawlessly with this code:
public class DateTimeToStringConverter implements Converter<DateTime, String> {
#Override
public String convert(DateTime source) {
return source.toDateTimeISO().toString();
}
}
The property shows up in the node:
Node[1] {
'__type__' = '...',
'entityEditedAt' = '2012-12-28T12:32:50.308+01:00',
'entityCreatedAt' = '2012-12-28T12:32:50.297+01:00',
...
}
However if I like to save the DateTime as Long (useful to sort by time in Cypher), it does not work at all. Here is my converter:
public class DateTimeToLongConverter implements Converter<DateTime, Long> {
#Override
public Long convert(DateTime source) {
return source.toDateTimeISO().getMillis();
}
}
The property is not saved on the node. Thus it is missing completely. No exception is thrown. It seems like the conversion code is not called at all.
The converters are hooked to Spring Data using code based configuration:
#Bean
public ConversionServiceFactoryBean conversionService() {
Set converters = Sets.newHashSet();
// These work!
converters.add(new DateTimeToStringConverter());
converters.add(new StringToDateTimeConverter());
// These don't :-(
//converters.add(new DateTimeToLongConverter());
//converters.add(new LongToDateTimeConverter());
ConversionServiceFactoryBean bean = new ConversionServiceFactoryBean();
bean.setConverters(converters);
return bean;
}
Any clues? I'm quite lost here, as it should work in my opinion...
Edit
I found following text in the Spring Data Neo4j documentation:
All fields convertible to a String using the Spring conversion services will be stored as a string.
Does this mean, that only conversions to string are supported? This seems rather limiting.
Tell SDN that you want to store your joda DateTime property as a long with:
#NodeEntity
public class MyEntity {
...
#GraphProperty(propertyType = Long.class)
private DateTime timestamp;
....
}
Then your registered DateTimeToLongConverter will kick in.
I am trying to submit a form from Ext JS 4 to a Spring 3 Controller using JSON. I am using Jackson 1.9.8 for the serialization/deserialization using Spring's built-in Jackson JSON support.
I have a status field that is initially null in the Domain object for a new record. When the form is submitted it generates the following json (scaled down to a few fields)
{"id":0,"name":"someName","status":""}
After submitted the following is seen in the server log
"nested exception is org.codehaus.jackson.map.JsonMappingException: Can not construct instance of com.blah.domain.StatusEnum from String value '': value not one of the declared Enum instance names"
So it appears that Jackson is expecting a valid Enum value or no value at all including an empty string. How do I fix this whether it is in Ext JS, Jackson or Spring?
I tried to create my own ObjectMapper such as
public class MyObjectMapper extends Object Mapper {
public MyObjectMapper() {
configure(DeserializationConfig.Feature.ACCEPT_EMPTY_STRING_AS_NULL_OBJECT, true);
}
}
and send this as a property to MappingJacksonMappingView but this didn't work. I also tried sending it in to MappingJacksonHttpMessageConverter but that didn't work. Side question: Which one should I be sending in my own ObjectMapper?
Suggestions?
The other thing you could do is create a specialized deserializer (extends org.codehaus.jackson.map.JsonDeserializer) for your particular enum, that has default values for things that don't match. What I've done is to create an abstract deserializer for enums that takes the class it deserializes, and it speeds this process along when I run into the issue.
public abstract class EnumDeserializer<T extends Enum<T>> extends JsonDeserializer<T> {
private Class<T> enumClass;
public EnumDeserializer(final Class<T> iEnumClass) {
super();
enumClass = iEnumClass;
}
#Override
public T deserialize(final JsonParser jp,
final DeserializationContext ctxt) throws IOException, JsonProcessingException {
final String value = jp.getText();
for (final T enumValue : enumClass.getEnumConstants()) {
if (enumValue.name().equals(value)) {
return enumValue;
}
}
return null;
}
}
That's the generic class, basically just takes an enum class, iterates over the values of the enum and checks the next token to match any name. If they do it returns it otherwise return null;
Then If you have an enum MyEnum you'd make a subclass of EnumDeserializer like this:
public class MyEnumDeserializer extends EnumDeserializer<MyEnum> {
public MyEnumDeserializer() {
super(MyEnum.class);
}
}
Then wherever you declare MyEnum:
#JsonDeserialize(using = MyEnumDeserializer.class)
public enum MyEnum {
...
}
I'm not familiar with Spring, but just in case, it may be easier to handle that on the client side:
Ext.define('My.form.Field', {
extend: 'Ext.form.field.Text',
getSubmitValue: function() {
var me = this,
value;
value = me.getRawValue();
if ( value === '' ) {
return ...;
}
}
});
You can also disallow submitting empty fields by setting their allowBlank property to false.
Ended up adding defaults in the EXT JS Model so there is always a value. Was hoping that I didn't have to this but it's not that big of a deal.
I have the same issue. I am reading a JSON stream with some empty strings. I am not in control of the JSON stream, because it is from a foreign service. And I am always getting the same error message. I tried this here:
mapper.getDeserializationConfig().with(DeserializationConfig.Feature.ACCEPT_EMPTY_STRING_AS_NULL_OBJECT);
But without any effect. Looks like a Bug.