Angular 5 – Upload/Get Images to/from Spring Boot Server

Upload files to Servlet containers, application need register a MultipartConfigElement class. But Spring Boot makes it more easy by configuring it automatically. In this tutorial, we’re gonna look at way to build an Angular 5 App Client to upload/get Images to/from Spring Boot RestApi Server.

Related posts:
How to upload MultipartFile with Spring Boot
MultipartFile – SpringBoot + JQuery Ajax + Bootstrap.
MultipartFile – SpringBoot + AngularJs + Bootstrap.
Angular 4 Firebase – Get List Files from Storage
Angular 5 – Upload/Get MultipartFile to/from Spring Boot Server

I. Technologies

– Angular 5
– Java 1.8
– Spring Boot 1.5.7.RELEASE
– Maven 3.3.9
– Spring Tool Suite – Version 3.8.1.RELEASE

II. Overview

1. Spring Boot Server

angular-5-upload-multipart-file-spring-boot-spring-structure

StorageService helps to init, delete all files, store file, load file
UploadController uses StorageService to provide Rest API: POST a file, GET all files
application.properties to configure parameters such as MultipartFile max size…
– Spring Boot Starter Web dependency in pom.xml

2. Angular 5 App Client

angular-5-upload-multipart-file-spring-boot-angular-structure

upload-file.service provides methods: push File to Storage and get Files.
list-upload.component gets and displays list of Files.
form-upload.component helps upload File.
details-upload.component is detail for each item in list of Files.

angular-5-upload-image-spring-boot-server-overview

III. Practice

1. Spring Boot Server
1.1 Create Spring Boot project

With Dependency:


	org.springframework.boot
	spring-boot-starter-web

1.2 Create Storage Service for File Systems

Create StorageService with 4 functions:
– public void store(MultipartFile file): save a file
– public Resource loadFile(String filename): load a file
– public void deleteAll(): remove all uploaded files
– public void init(): create upload directory

package com.javasampleapproach.uploadfiles.storage;

import java.io.IOException;
import java.net.MalformedURLException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.io.Resource;
import org.springframework.core.io.UrlResource;
import org.springframework.stereotype.Service;
import org.springframework.util.FileSystemUtils;
import org.springframework.web.multipart.MultipartFile;

@Service
public class StorageService {

	Logger log = LoggerFactory.getLogger(this.getClass().getName());
	private final Path rootLocation = Paths.get("upload-dir");

	public void store(MultipartFile file) {
		try {
			Files.copy(file.getInputStream(), this.rootLocation.resolve(file.getOriginalFilename()));
		} catch (Exception e) {
			throw new RuntimeException("FAIL!");
		}
	}

	public Resource loadFile(String filename) {
		try {
			Path file = rootLocation.resolve(filename);
			Resource resource = new UrlResource(file.toUri());
			if (resource.exists() || resource.isReadable()) {
				return resource;
			} else {
				throw new RuntimeException("FAIL!");
			}
		} catch (MalformedURLException e) {
			throw new RuntimeException("FAIL!");
		}
	}

	public void deleteAll() {
		FileSystemUtils.deleteRecursively(rootLocation.toFile());
	}

	public void init() {
		try {
			Files.createDirectory(rootLocation);
		} catch (IOException e) {
			throw new RuntimeException("Could not initialize storage!");
		}
	}
}
1.3 Create Upload Controller
package com.javasampleapproach.uploadfiles.controller;

import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.io.Resource;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.servlet.mvc.method.annotation.MvcUriComponentsBuilder;

import com.javasampleapproach.uploadfiles.storage.StorageService;

@Controller
public class UploadController {

	@Autowired
	StorageService storageService;

	List files = new ArrayList();

	@PostMapping("/post")
	public ResponseEntity handleFileUpload(@RequestParam("file") MultipartFile file) {
		String message = "";
		try {
			storageService.store(file);
			files.add(file.getOriginalFilename());

			message = "You successfully uploaded " + file.getOriginalFilename() + "!";
			return ResponseEntity.status(HttpStatus.OK).body(message);
		} catch (Exception e) {
			message = "FAIL to upload " + file.getOriginalFilename() + "!";
			return ResponseEntity.status(HttpStatus.EXPECTATION_FAILED).body(message);
		}
	}

	@GetMapping("/getallfiles")
	public ResponseEntity> getListFiles(Model model) {
		List fileNames = files
				.stream().map(fileName -> MvcUriComponentsBuilder
						.fromMethodName(UploadController.class, "getFile", fileName).build().toString())
				.collect(Collectors.toList());

		return ResponseEntity.ok().body(fileNames);
	}

	@GetMapping("/files/{filename:.+}")
	@ResponseBody
	public ResponseEntity getFile(@PathVariable String filename) {
		Resource file = storageService.loadFile(filename);
		return ResponseEntity.ok()
				.header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"" + file.getFilename() + "\"")
				.body(file);
	}
}
1.4 Config multipart.max-file

Open application.properties:

spring.http.multipart.max-file-size=500KB
spring.http.multipart.max-request-size=500KB

spring.http.multipart.max-file-size: limit total file size for each request.
spring.http.multipart.max-request-size: limit total request size for a multipart/form-data.

1.5 Init Storage for File System
package com.javasampleapproach.uploadfiles;

import javax.annotation.Resource;

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

import com.javasampleapproach.uploadfiles.storage.StorageService;

@SpringBootApplication
public class SpringBootUploadFileApplication implements CommandLineRunner {

	@Resource
	StorageService storageService;

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

	@Override
	public void run(String... arg) throws Exception {
		storageService.deleteAll();
		storageService.init();
	}
}
2. Angular 5 App Client
2.1 App Module
import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { HttpClientModule } from '@angular/common/http';

import { AppComponent } from './app.component';
import { ListUploadComponent } from './upload/list-upload/list-upload.component';
import { FormUploadComponent } from './upload/form-upload/form-upload.component';
import { DetailsUploadComponent } from './upload/details-upload/details-upload.component';
import { UploadFileService } from './upload/upload-file.service';

@NgModule({
  declarations: [
    AppComponent,
    ListUploadComponent,
    FormUploadComponent,
    DetailsUploadComponent
  ],
  imports: [
    BrowserModule,
    HttpClientModule
  ],
  providers: [UploadFileService],
  bootstrap: [AppComponent]
})
export class AppModule { }
2.2 Upload File Service
import { Injectable } from '@angular/core';
import { HttpClient, HttpRequest, HttpEvent } from '@angular/common/http';
import { Observable } from 'rxjs/Observable';

@Injectable()
export class UploadFileService {

  constructor(private http: HttpClient) { }

  pushFileToStorage(file: File): Observable> {
    const formdata: FormData = new FormData();

    formdata.append('file', file);

    const req = new HttpRequest('POST', '/post', formdata, {
      reportProgress: true,
      responseType: 'text'
    });

    return this.http.request(req);
  }

  getFiles(): Observable {
    return this.http.get('/getallfiles');
  }
}
2.3 Component for getting List of Images

list-upload.component.ts

import { Component, OnInit } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import { Observable } from 'rxjs/Observable';
import { UploadFileService } from '../upload-file.service';

@Component({
  selector: 'list-upload',
  templateUrl: './list-upload.component.html',
  styleUrls: ['./list-upload.component.css']
})
export class ListUploadComponent implements OnInit {

  showFile = false;
  fileUploads: Observable;

  constructor(private uploadService: UploadFileService) { }

  ngOnInit() {
  }

  showFiles(enable: boolean) {
    this.showFile = enable;

    if (enable) {
      this.fileUploads = this.uploadService.getFiles();
    }
  }
}

list-upload.component.html





List of Images

details-upload.component.ts

import { Component, OnInit, Input } from '@angular/core';

@Component({
  selector: 'details-upload',
  templateUrl: './details-upload.component.html',
  styleUrls: ['./details-upload.component.css']
})
export class DetailsUploadComponent implements OnInit {

  @Input() fileUpload: string;

  constructor() { }

  ngOnInit() {
  }

}

details-upload.component.html

{{fileUpload}}
2.4 Component for uploading Image

form-upload.component.ts

import { Component, OnInit } from '@angular/core';
import { HttpClient, HttpResponse, HttpEventType } from '@angular/common/http';
import { UploadFileService } from '../upload-file.service';

@Component({
  selector: 'form-upload',
  templateUrl: './form-upload.component.html',
  styleUrls: ['./form-upload.component.css']
})
export class FormUploadComponent implements OnInit {

  selectedFiles: FileList;
  currentFileUpload: File;
  progress: { percentage: number } = { percentage: 0 };

  constructor(private uploadService: UploadFileService) { }

  ngOnInit() {
  }

  selectFile(event) {
    const file = event.target.files.item(0);

    if (file.type.match('image.*')) {
      this.selectedFiles = event.target.files;
    } else {
      alert('invalid format!');
    }
  }

  upload() {
    this.progress.percentage = 0;

    this.currentFileUpload = this.selectedFiles.item(0);
    this.uploadService.pushFileToStorage(this.currentFileUpload).subscribe(event => {
      if (event.type === HttpEventType.UploadProgress) {
        this.progress.percentage = Math.round(100 * event.loaded / event.total);
      } else if (event instanceof HttpResponse) {
        console.log('File is completely uploaded!');
      }
    });

    this.selectedFiles = undefined;
  }
}

form-upload.component.html

{{progress.percentage}}%
2.5 App Component

app.component.ts

import { Component } from '@angular/core';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})
export class AppComponent {
  title = 'JavaSampleApproach';
  description = 'Angular-SpringBoot Demo';
}

app.component.html

{{title}}

{{description}}



2.6 Integrate Spring Boot Server with Angular 5 client

– Create proxy.conf.json file under project:

{
	"/": {
		"target": "http://localhost:8080",
		"secure": false
	}
}

– Edit package.json file for “start” script:

...
"scripts": {
    "ng": "ng",
    "start": "ng serve --proxy-config proxy.conf.json",
    "build": "ng build",
    "test": "ng test",
    "lint": "ng lint",
    "e2e": "ng e2e"
},
...
3. Check Results

Run Spring Boot Server and Angular 5 Client App, go to http://localhost:4200/:
angular-5-upload-image-spring-boot-server-run

Upload files and show list of Files:
angular-5-upload-image-spring-boot-server-result

IV. Sourcecode

SpringBootUploadFile
Angular5Upload-Images



By grokonez | March 30, 2018.


Related Posts


6 thoughts on “Angular 5 – Upload/Get Images to/from Spring Boot Server”

  1. An interesting thing about Angular is that uploading files is barely handled by anyone. It’s not mentioned in the docs and the first thing you find by using Google is a third party lib, ng2-file-upload .

  2. Hi,

    I am getting this error “Response for preflight has invalid HTTP status code 403.”
    I replicated the same example.
    I dont know what I m missing.

  3. “timestamp”: “2018-07-06T15:43:00.228+0000”,
    “status”: 400,
    “error”: “Bad Request”,
    “message”: “Required request part ‘file’ is not present”,

    bonjour je vient de suivre votre tutoriel mais j’ai cette erreur

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