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How to redirect s3 link from rest controller java

we have S3 storage ,there are a lot of some files, jpg,mp3 and others
what i need to do?
i need to redirect client to get the file from our s3 without uploading it on our server
and i want that clien get the file on his pc with name and extension
so it looks like clien send us uuid - we find link of this file on s3 and redirect it like this
#GetMapping("/test/{uuid}")
public ResponseEntity<Void> getFile(#PathVariable UUID uuid) {
var url = storageServiceS3.getUrl(uuid);
try {
var name = storageServiceS3.getName(uuid);
return ResponseEntity.status(HttpStatus.MOVED_PERMANENTLY)
.header(HttpHeaders.LOCATION, url)
.header(HttpHeaders.CONTENT_TYPE, new MimetypesFileTypeMap().getContentType(name))
.header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=" + name)
.build();
} catch (NoSuchKeyException ex) {
return ResponseEntity.status(HttpStatus.NOT_FOUND)
.build();
}
}
everything works good ,the file is downloading but one problem - the file has no name (its name still is key from s3) and no extension.
i think this code not works correctly
.header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=" + name)
is there any way to do this or i still need upload file to server and then send it to client ?

Finally i found solution- i use S3Presigner ,make presigned url and redirect it with simple Http response
#Bean
public S3Presigner getS3Presigner() {
return S3Presigner.builder()
.credentialsProvider(StaticCredentialsProvider.create(AwsBasicCredentials.create(ACCESS_KEY, SECRET_KEY)))
.region(Region.of(REGION))
.endpointOverride(URI.create(END_POINT))
.build();
}
public String getPresignedURL(UUID uuid) {
var name = getName(uuid);
var contentDisposition = "attachment;filename=" + name;
var contentType = new MimetypesFileTypeMap().getContentType(name);
GetObjectRequest getObjectRequest = GetObjectRequest.builder()
.bucket(BUCKET)
.key(uuid.toString())
.responseContentDisposition(contentDisposition)
.responseContentType(contentType)
.build();
GetObjectPresignRequest getObjectPresignRequest =
GetObjectPresignRequest.builder()
.signatureDuration(Duration.ofMinutes(5))
.getObjectRequest(getObjectRequest)
.build();
PresignedGetObjectRequest presignedGetObjectRequest =
s3Presigner.presignGetObject(getObjectPresignRequest);
return presignedGetObjectRequest.url().toString();
}
#GetMapping("/redirect/{uuid}")
public void redirectToS3(#PathVariable UUID uuid, HttpServletResponse response) {
try {
var URI = storageServiceS3.getPresignedURL(uuid);
response.sendRedirect(URI);
} catch (NoSuchKeyException | IOException e) {
response.setStatus(404);
}
}
It works pretty good ;)

#Алексеев станислав
Some work arround for this is consuming your rest service by javascript and add file's name in a new header response and rename file when download by client.
// don't forget to allow X-File-Name header on CORS in spring
headers.add("X-File-Name", nameToBeDownloaded );
Example on ANGULAR but can be parsed to other language
this.http.get(uri_link_spring_redirecting_to_S3, {
responseType: 'blob',
observe: 'response'
}).subscribe(
(response) => {
var link = document.createElement('a');
var file = new Blob([response.body], {
type: 'text/csv;charset=utf-8;'
});
link.href = window.URL.createObjectURL(file);
link.download = response?.headers?.get('X-File-Name');; 'download.csv';
link.click();
},
error => {
...
}
)

Changing a 404 response for REST API to a 200 empty response

I have a Spring Boot application written in Java that is a REST API. This service (Svc A) calls a REST API service (Svc B) with is also a Spring Boot Application written in Java. Svc B returns a 404 status code when no data was found. I need to change this response to a 200 status code and return an empty response object. I am not sure if or how to do this.
I can catch the error and determine if the 404 is this no data found error. However, I don't know how to change the response to a 200 empty response.
I am using a FeignClient to call the service. This is the error code that catches the 404:
#Component
public class FeignErrorDecoder implements ErrorDecoder {
Logger logger = LoggerFactory.getLogger(this.getClass());
#Override
public Exception decode(String methodKey, Response response) {
Reader reader = null;
String messageText = null;
switch (response.status()){
case 400:
logger.error("Status code " + response.status() + ", methodKey = " + methodKey);
case 404:
{
logger.error("Error took place when using Feign client to send HTTP Request. Status code " + response.status() + ", methodKey = " + methodKey);
try {
reader = response.body().asReader();
//Easy way to read the stream and get a String object
String result = CharStreams.toString(reader);
logger.error("RESPONSE BODY: " + result);
ObjectMapper mapper = new ObjectMapper();
//just in case you missed an attribute in the Pojo
mapper.disable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES);
//init the Pojo
ExceptionMessage exceptionMessage = mapper.readValue(result,
ExceptionMessage.class);
messageText = exceptionMessage.getMessage();
logger.info("message: " + messageText);
} catch(IOException ex) {
logger.error(ex.getMessage());
}
finally {
try {
if (reader != null)
reader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return new ResponseStatusException(HttpStatus.valueOf(200), messageText);
}
default:
return new Exception(response.reason());
}
}
}
I can change the status code to a 200 and it returns a 200 but I need to the response to have an empty response object.
The above code will return this response body of an error response object:
{
"statusCd" : "200",
"message" : "The Location not found for given Location Number and Facility Type Code",
"detailDesc" : "The Location not found for given Location Number and Facility Type Code. Error Timestamp : 2020-01-31 18:19:13"
}
I need it to return a response body like this:
200 - Empty Response
{
"facilityNumber": "923",
"facilityTimeZone": null,
"facilityAbbr": null,
"scheduledOperations": []
}

In case 404 just try
return new ResponseStatusException(HttpStatus.valueOf(200));

For anyone that has to do something this crazy...here is my solution:
Removed the FeignErrorCode file.
Added an exception to ControllerAdvice class like this:
#ExceptionHandler(FeignException.class)
public ResponseEntity<?> handleFeignException(FeignException fe, WebRequest request) {
ErrorDetails errorDetails = new ErrorDetails(new Date(), HttpStatus.valueOf(fe.status()), fe.getMessage(), request.getDescription(false));
String response = fe.contentUTF8();
if(response != null) {
ScheduledOperationsViewResponse scheduledOperationsViewResponse = new ScheduledOperationsViewResponse();
if (response.contains("Scheduled") || response.contains("Location")) {
HttpHeaders headers = new HttpHeaders();
scheduledOperationsViewResponse.setFacilityNumber(request.getParameter("facilityNumber"));
return new ResponseEntity<ScheduledOperationsViewResponse>(scheduledOperationsViewResponse, headers, HttpStatus.OK);
}
}
return new ResponseEntity<>(errorDetails, errorDetails.getStatus());
}

Determining the cause of org.apache.catalina.connector.ClientAbortException: java.io.IOException: Broken pipe with Spring Boot 1.5 and Angular 5

So I have an API that receives GET request (Spring Boot), generates an excel file and returns it back to the client (Angular) and it works however I have been getting the following exception below while the front end receives a 504 response for files that are a bit larger and longer to generate.
Caused by: org.apache.catalina.connector.ClientAbortException: java.io.IOException: Broken pipe
at org.apache.catalina.connector.OutputBuffer.realWriteBytes(OutputBuffer.java:393)
at org.apache.tomcat.util.buf.ByteChunk.flushBuffer(ByteChunk.java:426)
at org.apache.catalina.connector.OutputBuffer.doFlush(OutputBuffer.java:342)
This is the java code that takes the excel workbook and returns it back out as a response:
public ResponseEntity<?> doReturn(ResponseDTO responseDTO, String fileName, HttpServletRequest req,
String methodName) throws Exception {
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
Workbook workbook = responseDTO.getWorkbook();
ByteArrayOutputStream out = new ByteArrayOutputStream();
try {
workbook.write(out);
} catch (IOException e) {
throw e;
} finally {
try {
workbook.close();
} catch (IOException e) {
logger.info("User: " + user + " failed to close exported file from " + methodName);
}
}
ResponseEntity<?> resp = new ResponseEntity<>(out.toByteArray(), headers, HttpStatus.OK);
}
Here is the Angular code that issues the request:
exportwithparam(url, fileName, Params): Observable<string> {
let Headers = new HttpHeaders().set("Authorization", "Basic " + btoa(environment.roles.basicAuth)).set("Content-Type", "application/json");
return this.http
.get(url, { headers: Headers, responseType: 'arraybuffer', observe: 'response', withCredentials: true, params: Params })
.pipe(
map(res => {
let errmsg = "You have successfully exported " + fileName;
if (res.ok) {
let blob = new Blob([res.body], { type: 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet' });
if (window.navigator.msSaveOrOpenBlob) {
window.navigator.msSaveBlob(blob, fileName);
} else {
let objectUrl = URL.createObjectURL(blob);
let a = document.createElement('a');
a.href = objectUrl;
a.target = '_blank';
a.download = fileName;
document.body.appendChild(a);
a.click();
}
}
return errmsg;
}),
catchError((err: HttpErrorResponse): string => {
if (err.status == 504) {
throw "Gateway Time-out";
} else {
let errormessage = String.fromCharCode.apply(null, new Uint8Array(err.error));
throw errormessage;
}
})
)
}
I was wondering if there is anything I am doing wrong in the Java code that would cause this exception. However, if it is client that is dropping the connection then is there anything in Angular I can do ? I have tried setting a break point in VS Code just after the this.http.get and it seems for cases where the problem happens, it doesn't flow to the next line of code and directly goes to the catchError part at the bottom.
Also I need to note that this problem does not happen when I try this with both Spring Boot and Angular running in localhost. It happens when I either test this with Spring Boot running in our dev/test/prod environments. I know some of you may say the environment setting is the culprit but I just want to see if you guys notice anything before I draw that conclusion.
I have also tried just issuing the GET request as an URL with query params for these requests that would take longer to return a response and it also returns a 504 GATEWAY TIMEOUT.

Sendgrid v3: "Substitutions may not be used with dynamic templating"

I am trying to update my API Code from Sendgrid v2, to the actual Sendgrid v3, so my code used to look like this:
public void sendCreatedUserEmail(User user) {
Email from = new Email(FROM);
from.setName(EMAIL_NAME);
String subject = "Hello" + user.getName();
Email to = new Email(user.getEmail());
Content content = new Content("text/html", "Something");
Mail mail = new Mail(from, subject, to, content);
mail.personalization.get(0).addSubstitution("{name1}", user.getName());
mail.personalization.get(0).addSubstitution("{name2}", user.getName());
mail.setTemplateId(USER_TEMPLATE_ID);
SendGrid sg = new SendGrid(SENDGRID_API_KEY);
Request request = new Request();
try {
request.setMethod(Method.POST);
request.setEndpoint("mail/send");
request.setBody(mail.build());
Response response = sg.api(request);
} catch (IOException ex) {
logger.error(ex);
}
}
After some hours of research I changed for v3 to this:
(I separeted everthing for a cleaner view)
public void sendCreatedUserEmail(User user) {
Mail mail = new Mail();
Email from = new Email();
from.setName(EMAIL_NAME);
from.setEmail(FROM);
mail.setFrom(from);
String subject = "Hello, " + user.getName();
mail.setSubject(subject);
Personalization personalization = new Personalization();
Email to = new Email();
to.setEmail(user.getEmail());
to.setName(user.getName());
personalization.addTo(to);
personalization.setSubject(subject);
personalization.addSubstitution("{name2}",user.getName());
personalization.addSubstitution("{name1}",user.getName());
mail.addPersonalization(personalization);
Content content = new Content();
content.setType("text/html");
content.setValue("Something");
mail.addContent(content);
mail.setTemplateId(NEW_USER_TEMPLATE_ID);
SendGrid sg = new SendGrid(SENDGRID_API_KEY);
Request request = new Request();
try {
request.setMethod(Method.POST);
request.setEndpoint("mail/send");
request.setBody(mail.build());
Response response = sg.api(request);
System.out.println(response.getStatusCode());
System.out.println(response.getBody());
System.out.println(response.getHeaders());
} catch (IOException ex) {
logger.error(ex);
}
}
I am getting the following error:
ERROR ROOT - java.io.IOException: Request returned status Code 400Body:{"errors":[{"message":"Substitutions may not be used with dynamic templating","field":"personalizations.0.substitutions","help":"http://sendgrid.com/docs/API_Reference/Web_API_v3/Mail/errors.html#message.personalizations.substitutions"}]}
And I really don't know how to proceed! I've been reading the sendgrid documentation but I couldn't get it.
Some details that might help
- Java8 is the language
- MAVEN for dependencies
- IntelliJ for the IDE
Sorry for the possible mistakes, it's my first post and English is not my main language. Thank you!

V3 of the Sendgrid API uses Dynamic Template Data instead of substitutions.
Try this instead of using addSubstitution:
personalization.addDynamicTemplateData("{name2}",user.getName());
personalization.addDynamicTemplateData("{name1}",user.getName());
Sources:
https://github.com/sendgrid/sendgrid-java/blob/9bc569cbdb908dba609ed0d9d2691dff319ce155/src/main/java/com/sendgrid/helpers/mail/objects/Personalization.java
https://sendgrid.com/docs/ui/sending-email/how-to-send-an-email-with-dynamic-transactional-templates/

Try:
personalization.addDynamicTemplateData("name2",user.getName());
personalization.addDynamicTemplateData("name1",user.getName());

Sent request parameters to UploadAction in gwt-upload

I get gwt-upload working in a GAE application. As suggested, I implemented a Custom UploadAction to handle the storage of the file in the DataStore. The code goes like this:
public String executeAction(HttpServletRequest request,
List<FileItem> sessionFiles) throws UploadActionException {
logger.info("Starting: DatastoreUploadAction.executeAction");
String executeAction = super.executeAction(request, sessionFiles);
for (FileItem uploadedFile : sessionFiles) {
Long entityId = new Long(2001); // This is where i wanna use a request parameter
InputStream imgStream;
try {
imgStream = uploadedFile.getInputStream();
Blob attachment = new Blob(IOUtils.toByteArray(imgStream));
String contentType = uploadedFile.getContentType();
appointmentDao.setAppointmentAttachment(entityId, attachment,
contentType);
} catch (IOException e) {
logger.error("Unable to store file", e);
throw new UploadActionException(e);
}
}
return executeAction;
}
As you see, the DAO class requires the "EntityID" to store the uploaded file in the DataStore. Now i'm working with a hard-coded value and it goes fine, but i'd like to have the entityID sent by the client as a request parameter. The widget that does the upload is a MultiUploader:
private MultiUploader defaultUploader;
Is it posible to the MultiUploader -or any other Widget- to set a request parameter so i can use it in my UploadAction?

Yes, you can set it on your client-side code. There is method: MultiUploader #setServletPath(java.lang.String), for example:
final MultiUploader u = new MultiUploader();
...
...
...
u.setServletPath(u.getServletPath() + "?entityId="+myObject.getEntityId());
on server side:
String entityId= request.getParameter("entityId");
Read this for more information: Sending additional parameters to the servlet