In my application I am running an applet to scan a picture from client. I need to upload the scanned file to the server then to database. I can upload the file by submitting a form in JSP, but I need the applet to post the file to URL.
Any hep would be appreciated.
Here is the code:
public static void main(String[] args) throws Exception {
URL url = new URL("http://localhost:8080/spring/upload");
URLConnection connection = url.openConnection();
connection.setDoOutput(true);
connection.setRequestProperty("Content-Type", "text/html;charset=UTF-8");
connection.setRequestProperty("enctype", "multipart/form-data");
DataOutputStream printout = new DataOutputStream(
connection.getOutputStream());
printout.write(FileUtils.readFileToByteArray(new File("c:\\img_khar.jpg")));
printout.flush();
printout.close();
BufferedReader in = new BufferedReader(new InputStreamReader(
connection.getInputStream()));
String decodedString;
while ((decodedString = in.readLine()) != null) {
System.out.println(decodedString);
}
in.close();
}
I prefer to use http client from apache for cases like this. They provide a MultipartEntity class that can be added to your HttpPost.
http://hc.apache.org/httpcomponents-client-ga/httpmime/apidocs/org/apache/http/entity/mime/MultipartEntity.html
Related
I have been looking around for sample code how to call a Restful service written in Spring boot (deployed in different server/ip) from an EJB client.
I couldn't find a simple example or reference to guide me on how to implement an EJB client that can call a restful service(deployed in different server/ip). Could you please point me to a document or example that shows or describe how the two can interface/talk to each other.
I need to call the endpoint by passing two header parameters for authentication, if authentication is success then only retrieve the details from Rest and send back the response to EJB client.
I use something like this, try
`public void calExternal() throws ProtocolException,
MalformedURLException,
IOException,
NoSuchAlgorithmException,
InvalidKeyException {
URL myurl = new URL("API END POINT URL");
ObjectMapper mapper = new ObjectMapper();
HttpURLConnection conn = (HttpURLConnection) myurl.openConnection();
conn.setUseCaches(false);
conn.setDoInput(true);
conn.setDoOutput(true);
String payLoad = mapper.writeValueAsString("your payload here");
conn.setRequestMethod("POST");
conn.setRequestProperty("Content-Type", "application/json");
conn.setRequestProperty("AUTHORIZATION-TYPE", "HMAC");
try {
OutputStreamWriter wr = new OutputStreamWriter(conn.getOutputStream());
wr.write(payLoad);
wr.flush();
InputStream in = null;
int responseCode = conn.getResponseCode();
if (responseCode == 200) {
in = conn.getInputStream();
} else {
in = conn.getErrorStream();
}
String encoding = conn.getContentEncoding() == null ? "UTF-8" : conn.getContentEncoding();
String response = IOUtils.toString(in, encoding);
} catch (Exception e) {
e.printStackTrace();
}
}
I have a Spring Boot 2 Web application which is a blogging website, where I have a dynamic sitemap.xml file. The sitemap.xml gets updated whenever we add a new article in the repository. Now I need to serve the sitemap.xml file from outside of the project location. Consider the sitemap.xml is present in the following location:
/home/admin/sitemap.xml
My requirement is, whenever a user hit the url https://<my_url>/sitemap.xml then the file should be served from the mentioned location. I have added the mapping for the same.
#Configuration
#AutoConfigureAfter(DispatcherServletAutoConfiguration.class)
public class WebConfiguration implements WebMvcConfigurer {
#Override
public void addResourceHandlers(final ResourceHandlerRegistry registry) {
registry.addResourceHandler("/sitemap.xml/**").addResourceLocations("/home/admin/sitemap.xml");
}
}
But the code is not working. Can anyone suggest that, what I am doing wrong here.
Finally, I have solved this by writing a GetMapping. Many solutions on the internet are saying that to return the sitemap.xml file as a String. But please note Google will not read that sitemap.xml file for the wrong Content-Type header. The Content-Type must be "application/xml". Following is my #GetMapping
#GetMapping(value = "/sitemap.xml")
public void serveSiteMapFile(HttpServletResponse response) throws IOException {
response.setContentType("application/xml");
try (BufferedReader bufferedReader =
new BufferedReader(new FileReader(new File("/home/admin/sitemap.xml")))) {
String line;
StringBuilder siteMapBuilder = new StringBuilder();
while ((line = bufferedReader.readLine()) != null) {
siteMapBuilder.append(line);
}
ServletOutputStream outStream = response.getOutputStream();
outStream.println(siteMapBuilder.toString());
outStream.flush();
outStream.close();
}
}
My project is a java spark project that I have hosted on heroku. A part of the project requires that I download a particular file from my google drive into the application. I managed to set up everything when my application was running locally but as soon as I deployed the app it stopped working. This was regardless of the fact that when the app was running locally I used an Oauth2 client ID of type other and when I deployed the application I created a new one of type web application.
Below is a snippet of the authentication and download code:
public class AutoCalls {
/** Application name. */
private static final String APPLICATION_NAME = "calls-made";
private static final java.io.File DATA_STORE_DIR = new java.io.File(System.getProperty("target/classes/auth"), ".credentials/calls-made");
private static FileDataStoreFactory DATA_STORE_FACTORY;
private static final JsonFactory JSON_FACTORY = JacksonFactory.getDefaultInstance();
private static HttpTransport HTTP_TRANSPORT;
private static final List<String> SCOPES = Arrays.asList(DriveScopes.DRIVE);
static {
try {
HTTP_TRANSPORT = GoogleNetHttpTransport.newTrustedTransport();
DATA_STORE_FACTORY = new FileDataStoreFactory(DATA_STORE_DIR);
} catch (GeneralSecurityException | IOException t) {
System.exit(1);
}
}
public static void startDownload() throws IOException, ParseException {
Drive serv = getDriveService();
// drive stuff deleted
}
public static Credential authorize() throws IOException {
InputStream in = new FileInputStream("target/classes/auth/client_secret_*****************************************.apps.googleusercontent.com.json");
GoogleClientSecrets clientSecrets = GoogleClientSecrets.load(JSON_FACTORY, new InputStreamReader(in));
GoogleAuthorizationCodeFlow flow = new GoogleAuthorizationCodeFlow.Builder(HTTP_TRANSPORT, JSON_FACTORY, clientSecrets, SCOPES)
.setDataStoreFactory(DATA_STORE_FACTORY)
.setAccessType("offline")
.build();
Credential credential = new AuthorizationCodeInstalledApp(flow, new LocalServerReceiver()).authorize("user");
System.out.println("Credentials saved to " + DATA_STORE_DIR.getAbsolutePath());
return credential;
}
public static Drive getDriveService() throws IOException {
Credential credential = authorize();
return new Drive.Builder(HTTP_TRANSPORT, JSON_FACTORY, credential)
.setApplicationName(APPLICATION_NAME)
.build();
}
}
Currently when I try to initiate the download I get a URL in the Heroku logs a follows:
2017-02-20T10:32:28.656820+00:00 app[web.1]: Please open the following address in your browser:
2017-02-20T10:32:28.656908+00:00 app[web.1]: https://accounts.google.com/o/oauth2/auth?access_type=offline&client_id=************-vvdi7u6bmp1vc90sdidtnuiftdi1t49c.apps.googleusercontent.com&redirect_uri=http://localhost:48085/Callback&response_type=code&scope=https://www.googleapis.com/auth/drive
When I try open the URL in a browser I get an error:
Error: redirect_uri_mismatch
I cannot find any good step by step tutorial on accessing google drive contents on a java web application so any help would be arreiciated.
Generally, if OAuth works on server-A but not on server-B, it's because the redirect URL hasn't been configured correctly on the API Console. There is no reason why you would need to use a different client-ID because a single client-ID can be configured with multiple URLs, eg your local host and your heroku server. Another possibility is the use of https.
There is a separate problem in your code where you iterate on lista.isEmpty(). You should be iterating on nextPageToken != null. See the answer to Google drive rest API, Download files from root folder only
I have saved some images to local path of pc and saved the file name to db. Now i want to load all the image from db and show to html page using java script and thymemleaf. Browser says not allowed to load local resources , So i made a servlet in spring boot. But it does not showing image.
Servlet
#WebServlet("/admin/imgServlet")
public class AdminImageServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
#Override
public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException {
String urlImage = request.getParameter("admin");
response.setContentType("image/jpeg");
ServletOutputStream out;
out = response.getOutputStream();
FileInputStream fin = new FileInputStream("C:/Users/Public/Documents/" + urlImage);
BufferedInputStream bin = new BufferedInputStream(fin);
BufferedOutputStream bout = new BufferedOutputStream(out);
int ch = 0;
while ((ch = bin.read()) != -1) {
bout.write(ch);
}
bin.close();
fin.close();
bout.close();
out.close();
}
}
#Bean
public ServletRegistrationBean adminImageServlet() {
DispatcherServlet dispatcherServlet = new DispatcherServlet();
AnnotationConfigWebApplicationContext applicationContext = new AnnotationConfigWebApplicationContext();
applicationContext.register(AdminImageServlet.class);
dispatcherServlet.setApplicationContext(applicationContext);
ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean(dispatcherServlet, "/admin/imgServlet");
servletRegistrationBean.setName("imgServlet");
return servletRegistrationBean;
}
Java script for loading image
'<img src=imgServlet?admin='+articles.bannerImg+' class="img-responsive" />'
error i'm getting imgServlet:1 GET http://localhost/techtalks/admin/imgServlet?admin=pyjc4x0B.jpeg 404 (Not Found)
And i also want to load image from local resources to thymeleaf html page
model.addAttribute("localImg", "E:\\picz\\assasins.jpg"); spring controller will pass the Model like this and it will pass the image to respective file to html page like this.
<img th:src="#{${localImg}}"/>
Your Servlet code works for me. I am able to get the image successfully.
I presume the problem could be most likely the file name. Please input the file name as below (i.e. without 'e' in jpeg).
It should work if the file is present in the local path that you are referring.
pyjc4x0B.jpg
I am creating POC for RESTFUL Web service using Spring 4.0. Requirement is to receive MultipartFile as Response from REST WEB-Service.
REST Service Controller
#RequestMapping(value="/getcontent/file", method=RequestMapping.post)
public MultipartFile getMultipartAsFileAsObject() {
File file = new File("src/test/resources/input.docx");
FileInputStream input = new FileInputStream(file);
MultipartFile multipartFile = new MockMultipartFile("file",file.getName(),
"application/docx", IOUtils.toByteArray(input));
return multipartFile
}
I call this service using third party Clients and Apache Http Client as well. kindly have a look on output.
Using Third party REST client ie. Postman
output looks like Json -
{
"name" : "file",
"originalfilename" : "sample.docx",
"contentType" : "application/docx",
"content" : [
82,
101,
97,
100,
101,
32,
32,
.
.
.
.
.
]
}
Apache HTTP Client Sample code
private static void executeClient() {
HttpClient client = new DefaultHttpClient();
HttpPost postReqeust = new HttpPost(SERVER_URI);
try{
// Set Various Attributes
HttpResponse response = client.execute(postReqeust) ;
//Verify response if any
if (response != null)
{
InputStream inputStream = response.getEntity().getContent();
byte[] buffer = new byte[inputStream.available()];
inputStream.read(buffer);
OutputStream outputStream = new FileOutputStream
(new File("src/main/resource/sample.docx"));
outputStream.write(buffer);
outputStream.flush();
outputStream.close();
}
}
catch(Exception ex){
ex.printStackTrace();
}
Output of Apache Http client
file is getting Created but It is empty. (0 bytes).
I found some interesting answers from multiple stackoverflow questions.
Links are given below
file downloading in restful web services
what's the correct way to send a file from REST web service to client?
For Sending single file : (copied from above sources)
#GET
#Produces(MediaType.APPLICATION_OCTET_STREAM)
public Response getFile() {
File file = ... // Initialize this to the File path you want to serve.
return Response.ok(file, MediaType.APPLICATION_OCTET_STREAM)
.header("Content-Disposition", "attachment; filename=\"" + file.getName() + "\"" ) //optional
.build();
}
For Sending Zip file : (copied from above sources)
1) Approach First :
You can use above method to send any file / Zip.
private static final String FILE_PATH = "d:\\Test2.zip";
#GET
#Path("/get")
#Produces(MediaType.APPLICATION_OCTET_STREAM)
public Response getFile() {
File file = new File(FILE_PATH);
ResponseBuilder response = Response.ok((Object) file);
response.header("Content-Disposition", "attachment; filename=newfile.zip");
return response.build();
}
2) Approach Second :
#GET
#Path("/get")
#Produces(MediaType.APPLICATION_OCTET_STREAM)
public StreamingOutput helloWorldZip() throws Exception {
return new StreamingOutput(){
#Override
public void write(OutputStream arg0) throws IOException, WebApplicationException {
// TODO Auto-generated method stub
BufferedOutputStream bus = new BufferedOutputStream(arg0);
try {
Thread.currentThread().getContextClassLoader().getResource("");
File file = new File("d:\\Test1.zip");
FileInputStream fizip = new FileInputStream(file);
byte[] buffer2 = IOUtils.toByteArray(fizip);
bus.write(buffer2);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
};
}