通过Axios发送发布请求会在Spring-Boot后端生成一个空的RequestBody。 在Postman中工作，但不能通过Axios发布请求工作

Question

I have a react frontend and a spring backend. I have rest service for the backend that takes a summarizerData as an input and returns the same as output. I have a form which takes a textarea input and submit button. When sending a post request through axios i am getting an empty object. I have tested the api through postman but when submitting it through axios, i am getting a 500 internal error.

I have enabled CORS in the RestController.

Please let me know what is the issue SummarizerData Pojo

@Entity(name = "user_text_data")
@Getter
@Setter
@ToString
public class SummarizerData {


    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Integer id;

    @Column
    private String paragraph;


    @Column
    private LocalDateTime creationDate;

    @Transient
    private List<Sentence> summarizedSentences;


    public SummarizerData(){

    }

    public SummarizerData(String paragraph){
        this.paragraph = paragraph;
        this.creationDate = LocalDateTime.now();
    }


}

TextSummarizerController

@RepositoryRestController
@RequestMapping("/api")
public class TextSummarizerController{

    @Autowired
    SummarizerDataRepository repository;

    Logger logger = Logger.getLogger(TextSummarizerController.class.getName());


    @CrossOrigin
    @RequestMapping(method = RequestMethod.POST, value = "/summarize")
    public @ResponseBody SummarizerData getSummarizerData(@RequestBody SummarizerData data ){
        System.out.println("Returning Summarized Data");
        SummaryTool summaryTool = new SummaryTool();

        logger.info(data.toString());
        repository.save(data);
        data.setSummarizedSentences(summaryTool.startSummarization(data.getParagraph()));
        return data;
    }



}

React FrontEnd

import React, { Component } from 'react';
import './App.css';
import 'bootstrap/dist/css/bootstrap.min.css';
import Navbar from './components/Navbar';
import ParagraphEntry from './components/ParagraphEntry';
import {BrowserRouter as Router, Route} from 'react-router-dom';
import axios from 'axios';
class App extends Component {



  constructor(props){
    super(props);

    this.state = {
      "summarizerData" : {}, 
      "paragraph" : ""
    } ; 
  }



  onChange = (e) => {
    this.setState({"paragraph" : e.target.value});
  };

onSubmit= (e) => {
    e.preventDefault();
    var headers = {
      'Content-Type': 'application/json' 
  }
    const summarizerData = {
        "paragraph" : this.state.paragraph,
        "creationDate" : "2019-03-10T00:58:23",
        "summarizedSentences" :null
    };

    axios.post('http://localhost:8080/api/summarize',{summarizerData}, {headers})
        .then(res => console.log(res.data))
    console.log(summarizerData);


}


handleClear = (e) => {
  console.log(e);
  e.target.value = "";
  this.setState({"paragraph" : ""});

}
  render() {
    return (

      <div className="App">

       <Navbar />

       <ParagraphEntry onChange = {this.onChange} onSubmit={this.onSubmit} handleClear = {this.handleClear}  paragraph = {this.state.paragraph}/>


      </div>

    );
  }
}

export default App;

Error logs

Returning Summarized Data
2019-03-18 00:10:19.487  INFO 8336 --- [nio-8080-exec-5] c.n.t.s.rest.TextSummarizerController    : SummarizerData(id=null, paragraph=null, creationDate=null, summarizedSentences=null)
2019-03-18 00:10:19.491  WARN 8336 --- [nio-8080-exec-5] o.h.engine.jdbc.spi.SqlExceptionHelper   : SQL Error: 1048, SQLState: 23000
2019-03-18 00:10:19.491 ERROR 8336 --- [nio-8080-exec-5] o.h.engine.jdbc.spi.SqlExceptionHelper   : Column 'creation_date' cannot be null
2019-03-18 00:10:19.495 ERROR 8336 --- [nio-8080-exec-5] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.dao.DataIntegrityViolationException: could not execute statement; SQL [n/a]; constraint [null]; nested exception is org.hibernate.exception.ConstraintViolationException: could not execute statement] with root cause

java.sql.SQLIntegrityConstraintViolationException: Column 'creation_date' cannot be null
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:117) ~[mysql-connector-java-8.0.15.jar:8.0.15]
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97) ~[mysql-connector-java-8.0.15.jar:8.0.15]
    at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:122) ~[mysql-connector-java-8.0.15.jar:8.0.15]
    at com.mysql.cj.jdbc.ClientPreparedStatement.executeInternal(ClientPreparedStatement.java:970) ~[mysql-connector-java-8.0.15.jar:8.0.15]

The highlight in the above is SummarizerData with all fields as null.

I am a react beginner so pls let me know of any mistakes.

Thanks

Answer 1

The problem is that you unnecessarily wrap summarizerData and headers with object constructor operator ( {} ). You have already created the objects before and this should resolve your issue:

axios.post('http://localhost:8080/api/summarize', summarizerData, headers)

What {summarizerData} does is create an object like this:

{
  "summarizerData": {
    "paragraph": this.state.paragraph,
    "creationDate": "2019-03-10T00:58:23",
    "summarizedSentences": null
  }
}

Which cannot be mapped to SummarizerData in your backend. You can use Devloper Tools ( Chrome , Firefox ) to investigate your HTTP calls. It will allow you eg to see what is actually sent in request body, see request and response headers and it's values etc.