D10030, JSR303, @NotNull message

This chapter is a little same as D10029, but we could define the info node of JSON message instead of the default message as following:

must not be null

It’s useful in many business scenarios. For example you want to write a method to verify the username and password when logging, here are two parameters:

• username: ( Path Parameter )
• password: ( Query Parameter )

And in your requirement, you want to define some validation rules such as following:

• When the username is null, the message should be Sorry, the system require you input the 'username'.
• When the password is null, the system should say Hi, you have not provide your password, did you forget ?.

For above requirement you can do as following in zero.

Demo projects:

• Standalone - 6083: up-rhea

Rules:

1. JSR303 is only supported in Agent component in zero system, it means that after you have send the message to event bus, the JSR303 will be effectiveness.
2. When you write the code with the Interface Style ( Will introduce in forward tutorials ), JSR303 will not support this kind of situation.
3. For @BodyParam, it also impact Agent component only, but could support Interface Style instead of JSR303 and could provide more useful validations.

1. Source Code

package up.god.micro.validation;

import io.vertx.up.annotations.EndPoint;

import javax.validation.constraints.NotNull;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.QueryParam;

@EndPoint
@Path("/api/jsr303")
public class NotNullMessageActor {

    @Path("notnull/message")
    @GET
    public String verify(
            @NotNull(message = "Sorry, the system require you input the 'username'")
            @QueryParam("username") final String username,
            @NotNull(message = "Hi, you have not provide your password, did you forget ?")
            @QueryParam("password") final String password
    ) {
        return "Hi, " + username + ", Your password is: " + password;
    }
}

Here we could see:

The message attribute ‘message’ also belong to JSR303, Bean Validation, you can set any response error message that you wanted here.

2. Testing

URL : http://localhost:6083/api/jsr303/notnull/message

Method : GET

Response :

{
    "code": -60000,
    "message": "[ERR-60000] (Validator) Web Exception occus: (400) - Request validation handler, class = class up.god.micro.validation.NotNullMessageActor, method = public java.lang.String up.god.micro.validation.NotNullMessageActor.verify(java.lang.String,java.lang.String), message = Hi, you have not provide your password, did you forget ?.",
    "info": "Hi, you have not provide your password, did you forget ?"
}

** URL** : http://localhost:6083/api/jsr303/notnull/message?password=111111

Method : GET

Response :

{
    "code": -60000,
    "message": "[ERR-60000] (Validator) Web Exception occus: (400) - Request validation handler, class = class up.god.micro.validation.NotNullMessageActor, method = public java.lang.String up.god.micro.validation.NotNullMessageActor.verify(java.lang.String,java.lang.String), message = Sorry, the system require you input the 'username'.",
    "info": "Sorry, the system require you input the 'username'"
}

The successful message should be as following, URL:

http://localhost:6083/api/jsr303/notnull/message?password=111111&username=Lang

{
    "data": "Hi, Lang, Your password is: 111111"
}

3. Summary

Please be careful that JSR303 for this validation do not focus on the validation sequence, it just like above examples that the password is validated first, then the username. Here we have defined our own message for JSR303 validation instead of default validation messages. In this situation you can work in your real business requirements for more extensions to do user-defined business validation information.