devstory

Le exemple de Upload file avec Spring Boot et jQuery Ajax

  1. Objectif de la leçon
  2. Créer un projet Spring Boot
  3. Form, Controller, Exception Handler
  4. Javascript, View

1. Objectif de la leçon

Dans cette leçon, nous allons créer une application Spring Boot file upload avec jQuery Ajax. Ci-dessous sont les images d'aperçu de l'application à effectuer :
Avertissez lorsqu'une erreur se produit :
Voir plus l'exemple du fichier Upload avec Spring Boot sans avoir besoin de AJAX:
File Upload + AngularJS:

2. Créer un projet Spring Boot

Sur Eclipse créez un projet Spring Boot:
pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
    http://maven.apache.org/xsd/maven-4.0.0.xsd">
    
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.o7planning</groupId>
    <artifactId>SpringBootFileUploadAjax</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>SpringBootFileUploadAjax</name>
    <description>Spring Boot + File Upload + JQuery Ajax</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.0.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>
SpringBootFileUploadAjaxApplication.java
package org.o7planning.sbfileupload;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class SpringBootFileUploadAjaxApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringBootFileUploadAjaxApplication.class, args);
    }
    
}

3. Form, Controller, Exception Handler

La classe UploadForm se présente les données du formulaire HTML.
UploadForm.java
package org.o7planning.sbfileupload.form;

import org.springframework.web.multipart.MultipartFile;

public class UploadForm {

    private String description;

    private MultipartFile[] files;

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public MultipartFile[] getFiles() {
        return files;
    }

    public void setFiles(MultipartFile[] files) {
        this.files = files;
    }

}
MainController.java
package org.o7planning.sbfileupload.controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;

@Controller
public class MainController {

    @GetMapping("/")
    public String index() {
        return "upload";
    }

}
La classe MainRESTController définit un REST API pour traiter les données des fichiers téléchargés par des utilisateurs. Ce REST API sera appelé par jQuery Ajax (Voir dans main.js).
MainRESTController.java
package org.o7planning.sbfileupload.restcontroller;

import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;

import org.o7planning.sbfileupload.form.UploadForm;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

@RestController
public class MainRESTController {

    // Linux: /home/{user}/test
    // Windows: C:/Users/{user}/test
    private static String UPLOAD_DIR = System.getProperty("user.home") + "/test";

    @PostMapping("/rest/uploadMultiFiles")
    public ResponseEntity<?> multiUploadFileModel(@ModelAttribute UploadForm form) {

        System.out.println("Description:" + form.getDescription());

        String result = null;
        try {

            result = this.saveUploadedFiles(form.getFiles());

        }
        // Here Catch IOException only.
        // Other Exceptions catch by RestGlobalExceptionHandler class.
        catch (IOException e) {
            e.printStackTrace();
            return new ResponseEntity<>("Error: " + e.getMessage(), HttpStatus.BAD_REQUEST);
        }

        return new ResponseEntity<String>("Uploaded to: <br/>" + result, HttpStatus.OK);

    }

    // Save Files
    private String saveUploadedFiles(MultipartFile[] files) throws IOException {

        // Make sure directory exists!
        File uploadDir = new File(UPLOAD_DIR);
        uploadDir.mkdirs();

        StringBuilder sb = new StringBuilder();

        for (MultipartFile file : files) {

            if (file.isEmpty()) {
                continue;
            }
            String uploadFilePath = UPLOAD_DIR + "/" + file.getOriginalFilename();

            byte[] bytes = file.getBytes();
            Path path = Paths.get(uploadFilePath);
            Files.write(path, bytes);

            sb.append(uploadFilePath).append("<br/>");
        }
        return sb.toString();
    }
}
La taille par défaut du fichier téléchargé sur le serveur ne doit pas dépasser 1 MB. Et si l'utilisateur télécharge plusieurs fichiers en même temps, la taille totale des fichiers ne doit pas dépasser 1 MB. Cependant, vous pouvez configurer afin de modifier ces paramètres.
application.properties
spring.servlet.multipart.max-file-size=1MB
spring.servlet.multipart.max-request-size=5MB

spring.thymeleaf.cache=false
RestGlobalExceptionHandler est une classe personnalisée, étendue de la classe ResponseEntityExceptionHandler. Dans cette classe, vous pouvez gérer des exceptions lancé (throw) par des méthodes REST. Ceci vous aide à résoudre des exceptions centralisées au lieu de gérer chaque méthode REST.
RestGlobalExceptionHandler.java
package org.o7planning.sbfileupload.exceptionhandler;

import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.multipart.MultipartException;
import org.springframework.web.servlet.mvc.method.annotation.ResponseEntityExceptionHandler;

import javax.servlet.http.HttpServletRequest;

@ControllerAdvice
public class RestGlobalExceptionHandler extends ResponseEntityExceptionHandler {

    // Catch max file size Exception.
    @ExceptionHandler(MultipartException.class)
    @ResponseBody
    public ResponseEntity<?> handleControllerException(HttpServletRequest request, Throwable ex) {

        HttpStatus status = this.getStatus(request);
        return new ResponseEntity<String>("(Message in RestGlobalExceptionHandler *): " + ex.getMessage(), status);
    }

    // Cache Other Exception
    @ExceptionHandler(Exception.class)
    @ResponseBody
    public ResponseEntity<?> handleControllerRootException(HttpServletRequest request, Throwable ex) {

        HttpStatus status = this.getStatus(request);
        return new ResponseEntity<String>("(Message in RestGlobalExceptionHandler **): " + ex.getMessage(), status);
    }

    private HttpStatus getStatus(HttpServletRequest request) {
        Integer statusCode = (Integer) request.getAttribute("javax.servlet.error.status_code");
        if (statusCode == null) {
            return HttpStatus.INTERNAL_SERVER_ERROR;
        }
        return HttpStatus.valueOf(statusCode);
    }

}

4. Javascript, View

upload.html
<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">
   <head>
      <title>Upload Files</title>
      <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
      <script type="text/javascript" th:src="@{/main.js}"></script>
   </head>
   <body>
      <h1>Spring Boot File Upload with jQuery Ajax</h1>
      <form method="POST" enctype="multipart/form-data" id="fileUploadForm">
         Description: <br/>
         <input type="text" name="description" style="width:350px;"/>
         <br/><br/>                 
         File to upload (1): <input type="file" name="files"/><br />      
         File to upload (2): <input type="file" name="files"/><br />    
         File to upload (3): <input type="file" name="files"/><br />    
         File to upload (4): <input type="file" name="files"/><br />    
         File to upload (5): <input type="file" name="files"/><br />    
         <input type="submit" value="Submit" id="submitButton"/>
      </form>
      <h2>Upload Results:</h2>
      <div style="border:1px solid #ccc;padding: 5px;">
         <span id="result"></span>
      </div>
      
   </body>
</html>
main.js
$(document).ready(function() {

    $("#submitButton").click(function(event) {

        // Stop default form Submit.
        event.preventDefault();

        // Call Ajax Submit.

        ajaxSubmitForm();

    });

});

function ajaxSubmitForm() {

    // Get form
    var form = $('#fileUploadForm')[0];

    var data = new FormData(form);


    $("#submitButton").prop("disabled", true);

    $.ajax({
        type: "POST",
        enctype: 'multipart/form-data',
        url: "/rest/uploadMultiFiles",
        data: data,

        // prevent jQuery from automatically transforming the data into a query string
        processData: false,
        contentType: false,
        cache: false,
        timeout: 1000000,
        success: function(data, textStatus, jqXHR) {

            $("#result").html(data);
            console.log("SUCCESS : ", data);
            $("#submitButton").prop("disabled", false);
            $('#fileUploadForm')[0].reset();
        },
        error: function(jqXHR, textStatus, errorThrown) {  

            $("#result").html(jqXHR.responseText);
            console.log("ERROR : ", jqXHR.responseText);
            $("#submitButton").prop("disabled", false);

        }
    });

}

Tutoriels Spring Boot

Show More

Tutoriels Spring Boot

Show More

Articles les plus récents

Show More