JSON VALIDATOR

Easy annotation based validator.

Predefined validations right out of the box i.e. required, minItems, maxItems, email, numeric etc.

Supports dynamic validations using conditional, customTask(s).

Supports ValidValues annotation for set of valid values.

Can be used with any framework of Java or a Rest based Java API.

A user validator map, user defined message set, valid value data set can be configured using builder pattern.

Output of the validation contains type and a json path(even the complex one) to rightly identify the issues.

Pass an Object Instance or List instance directly to the validation util.

Steps:

1. Add Maven dependency

<dependency>
    <groupId>com.github.salilvnair</groupId>
    <artifactId>json-validator</artifactId>
    <version>1.0.2</version>
</dependency>

2. Annotate a class or a field using @JsonKeyValidation , class should be implementing the marker interface named JsonRequest

@JsonKeyValidation 
public class School implements JsonRequest {
   ....
}

3. Set it as required, conditional, numeric, email erc.

@JsonKeyValidation(required=true, numeric=true)
private String id;

@JsonKeyValidation(conditional=true, condition="validateName")
private String name;

@JsonKeyValidation(email=true)
private String email;

4. Call the validator by passing the JsonValidatorContext using JsonValidator

JsonValidatorContext jsonValidatorContext = JsonValidatorContext
                                                .builder()
                                                .build();

List<ValidationMessage>  validationMsgList  = JsonValidator.validate(school, jsonValidatorContext);

5. User defined map can be passed in the builder which can be later used in customTask(s) or in Conditional validators.

Map<String,Object> validatorMap  = new HashMap<>();
validatorMap.put("alumini", "Hogward");

JsonValidatorContext jsonValidatorContext = JsonValidatorContext
                                                .builder()
                                                .userValidatorMap(validatorMap).build();

List<ValidationMessage>  validationMsgList  = JsonValidator.validate(school, jsonValidatorContext);

Complete Usage:

@JsonKeyValidation(id="School", customTaskValidator=SchoolCustomTask.class)
public class School implements JsonRequest {
	@JsonKeyValidation(required=true, message="User defined message!")
	private long id;
	@JsonKeyValidation(conditional=true, condition="validateAlumini")
	private String name;
	@JsonKeyValidation(required=true)
	private HeadMaster headMaster;
	@JsonKeyValidation(
		required=true,
		minItems=4,	
		userDefinedMessages = {
				@UserDefinedMessage(
						validatorType=ValidatorType.REQUIRED,
						message="Students are mandatory in a school",
						messageType=MessageType.ERROR
				),
				@UserDefinedMessage(
						validatorType=ValidatorType.MINITEMS,
						message="Minimum 4 students should be there at "+JsonKeyValidationConstant.PATH_PLACEHOLDER,
						messageType = MessageType.WARNING
				)
		}
	)
	private List<Student> students;
}

public class SchoolCustomTask extends AbstractCustomJsonValidatorTask {
	public String validateAlumini(JsonValidatorContext jsonValidatorContext) {
		School school = (School) jsonValidatorContext.getJsonRequest();
		Map<String,Object> validatorMap = jsonValidatorContext.getUserValidatorMap();
		if(!validatorMap.isEmpty() && school.getName()!=null) {
			String alumini  = (String) validatorMap.get("alumini");
			if(!school.getName().contains(alumini)){
				return "Only "+alumini+" alumini schools are allowed";
			}
		}
		return null;
	}
}