This question is in reference of the question:
Setting the response content-type without using HttpServletResponse
with the following code:
#RequestMapping("handle.htm")
public ResponseEntity<String> handle() {
HttpHeaders responseHeaders = new HttpHeaders();
responseHeaders.setContentType(new MediaType("text", "plain"));
//responseHeaders.set("myheader","xyz");
return new ResponseEntity<String>("Hello World", responseHeaders, HttpStatus.CREATED);
}
I am getting following error:
java.lang.NoSuchMethodError: org.springframework.http.HttpHeaders.readOnlyHttpHeaders(Lorg/springframework/http/HttpHeaders;)Lorg/springframework/http/HttpHeaders;
org.springframework.http.HttpEntity.<init>(HttpEntity.java:100)
org.springframework.http.HttpEntity.<init>(HttpEntity.java:70)
org.springframework.http.HttpEntity.<clinit>(HttpEntity.java:58)
...
But in spring API docs there is a static method:
static HttpHeaders readOnlyHttpHeaders(HttpHeaders headers)
Then why it is giving such error?
Thanks...
I have had a look in the code, and it must work. Double check everything that you do not use different (old) versions of that jar.
Related
I'm trying to POST a multipart/form-data using Spring RestTemplate with a byte array as the file to upload and it keeps failing (Server rejects with different kinds of errors).
I'm using a MultiValueMap with ByteArrayResource. Is there something I'm missing?
Yes there is something missing.
I have found this article:
https://medium.com/#voziv/posting-a-byte-array-instead-of-a-file-using-spring-s-resttemplate-56268b45140b
The author mentions that in order to POST a byte array using Spring RestTemplate one needs to override getFileName() of the ByteArrayResource.
Here is the code example from the article:
private static void uploadWordDocument(byte[] fileContents, final String filename) {
RestTemplate restTemplate = new RestTemplate();
String fooResourceUrl = "http://localhost:8080/spring-rest/foos"; // Dummy URL.
MultiValueMap<String, Object> map = new LinkedMultiValueMap<String, Object>();
map.add("name", filename);
map.add("filename", filename);
// Here we
ByteArrayResource contentsAsResource = new ByteArrayResource(fileContents) {
#Override
public String getFilename() {
return filename; // Filename has to be returned in order to be able to post.
}
};
map.add("file", contentsAsResource);
// Now you can send your file along.
String result = restTemplate.postForObject(fooResourceUrl, map, String.class);
// Proceed as normal with your results.
}
I tried it and it works!
I added an issue to send a request from java client to Python service in FastApi and sending a ByteArrayResource instaead of simple byte[] fixed the issue.
FastAPI server returned: "Expected UploadFile, received: <class 'str'>","type":"value_error""
I want to make a multipart request to some external API (created using Spring Boot) but all I get is Required request part 'file' is not present.
I know the source code of the external API but I can't modify it. It looks like this:
#PostMapping("/upload")
public ResponseEntity handleFileUpload(#RequestParam("file") MultipartFile file){
return ResponseEntity.ok().build();
}
And from my application I create and send requests exactly like on the following snippet:
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.MULTIPART_FORM_DATA);
MultiValueMap<String, Object> body
= new LinkedMultiValueMap<>();
body.add("file", "dupa".getBytes());
HttpEntity<MultiValueMap<String, Object>> requestEntity
= new HttpEntity<>(body, headers);
RestTemplate restTemplate = new RestTemplate();
ResponseEntity<String> response = restTemplate
.postForEntity("http://api:8080/upload", requestEntity, String.class);
return response.getBody();
What's the reason it doesn't work? The above code rewritten using Apache HttpClient works like charm.
You basically have two options, the solution with byte array:
map.add("file", new ByteArrayResource(byteArrayContent) {
#Override
public String getFilename() {
return "yourFilename";
}
});
I remember having a problem with just adding a byte array, so you need to have a filename too and use ByteArrayResource.
Or adding a File:
map.add("file", new FileSystemResource(file));
I would like to return in my #Controller static HTML website that was generated by other process. Let's say that generated .html files are in /tmp/generated. I'm trying to read file and pass its content to ResponseEntity:
#GetMapping(value = "test")
ResponseEntity<String> test(#RequestParam("filename") String filename) throws IOException {
String content = new String(Files.readAllBytes(Paths.get("/tmp/generated/" + filename)), "UTF-8");
final HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.TEXT_HTML);
return new ResponseEntity<String>(content, headers, HttpStatus.OK);
}
But when I open url in browser I get badly encoded html content (stating and ending with '"'):
"\u003chtml\u003e\n\u003chead\u003e\n \u003cmeta charset\u003d\"utf-8\" /\u003e\n \u003cmeta http-equiv\u003d\"X-UA-Compatible\" content\u003d\"IE\u003dedge\" /\u003e\n \u003cmeta name\u003d\"viewport\" content\u003d\"width\u003ddevice-width, initial-scale\u003d1\" /\u003e [.....]
If I add produces = MediaType.TEXT_HTML_VALUE to my #GetMapping annotation then I get 406 Not Acceptable error response (but no exception in my spring app)...
How to fix it?
I'm not sure why you are facing problems when using produces in your mapping.
I gave a quick try and it worked for me.
#GetMapping(value = "test", produces=MediaType.TEXT_HTML_VALUE)
public ResponseEntity<String> test(#RequestParam("filename") String filename) throws IOException {
String content = new String(Files.readAllBytes(Paths.get("/tmp/generated/" + filename)), "UTF-8");
return new ResponseEntity<String>(content, HttpStatus.OK);
}
Tested in Chrome browser:
File
NOTE: I tested this controller using SpringBoot v2.0.5.RELEASE
Cheers!
I have successfully build application with Spring Boot 1.5.2.RELEASE and it will return static HTML site from any directory
you can checkout here
I really like the solution I have with RestTemplate but soon it will be depreciated with future spring releases. I am trying to send some text to a third party api using WebClient
String text = URLEncoder.encode(text,"UTF-8");
WebClient webClient = WebClient.builder()
.baseUrl(BASE_URL)
.defaultHeader("Key","af999-e99-4456-b556-4ef9947383d")
.defaultHeader("src", srcLang)
.defaultHeader("tgt", tgtLang)
.defaultHeader("text", text)
.build();
Then send a post here:
Mono<String> response = webClient.post().uri("/google/rtv/text")
.retrieve()
.bodyToMono(String.class);
Trying to parse based off of the legacy response:
private String parseJson( Mono<String> response) {
ObjectMapper mapper = new ObjectMapper();
JsonNode root = null;
JsonNode review = null;
//TODO: create an object and map it here. We need to save the original review too.
try {
root = mapper.readTree(response.toString());
review = root.path("message");
} catch (IOException e) {
e.printStackTrace();
}
return review.asText();
}
Later I need to parse the response but right now I am getting an error saying:
com.fasterxml.jackson.core.JsonParseException: Unrecognized token 'MonoFlatMap': was expecting ('true', 'false' or 'null')
at [Source: (String)"MonoFlatMap"; line: 1, column: 23]
and later:
java.lang.NullPointerException: null
What I am trying to accomplish is something like I have done with RestTemplate.
Like so:
UriComponentsBuilder builder = UriComponentsBuilder
.fromUriString(URL)
.queryParam("src", src)
.queryParam("tgt", tgt)
.queryParam("text", text);
ResponseEntity<String> response = restTemplate.exchange(builder.toUriString(), HttpMethod.GET, request, String.class);
then set my header for the subscription globally.
private ClientHttpResponse intercept(HttpRequest request, byte[] body,
ClientHttpRequestExecution execution) throws IOException {
request.getHeaders().add("Key","af999-e99-4456-b556-4ef9947383d");
ClientHttpResponse response = execution.execute(request, body);
return response;
}
#Bean
public RestTemplate restTemplate() {
RestTemplate restTemplate = new RestTemplate();
restTemplate.setInterceptors(Collections.singletonList(this::intercept));
return restTemplate;
}
Advice?
The problem happens here:
root = mapper.readTree(response.toString());
This code snippet is trying to serialize a Mono<String> as a String, when a Mono is a reactive type that can provide that String value eventually.
You could call response.block() and getting the resulting String, but this would be a blocking call and Reactor forbids that if in the middle of a reactive execution. This is done for good reasons, since this will block one of the few threads that your web application is using and can cause it to stop serving other requests.
You could instead have something like:
Mono<String> review = response.map(r -> parseJson(r);
And then reuse that new value down the line.
Note that WebClient natively supports JSON deserialization and you could deserialize the whole payload like so:
Mono<Review> review = webClient.post().uri("/google/rtv/text")
.retrieve()
.bodyToMono(Review.class);
When I try to make a get request with Spring's RestTemplate, it gives 400 BAD Request. I can call the same url from javascript successfully with the headers below :
But the code below does not work. What might be the cause?
public Entity getEntityByUri(String uri) {
String req = "http://live.dbpedia.org/sparql?query=DESCRIBE%20%3Chttp://dbpedia.org/resource/Concept_learning%3E&format=application%2Fjson-ld";
HttpHeaders headers = new HttpHeaders();
headers.setAccept(Arrays.asList(MediaType.ALL));
HttpEntity<String> httpEntity = new HttpEntity<String>(headers);
new RestTemplate().exchange(req, HttpMethod.GET, httpEntity, Map.class);
Entity entity = new Entity();
return entity;
}
Your url is already encoded. Popular browsers such as Chrome are capable of understanding and responding appropriately. However, it's not the same case with RestTemplate.
I had to decode your uri here and the decoded uri is DESCRIBE <http://dbpedia.org/resource/Concept_learning>
Having checked the browser console, I got to know you have two query strings passed in the url, they are query and format holding values DESCRIBE <http://dbpedia.org/resource/Concept_learning> and application/json-ld respectively.
I assume Entity class is the pojo class of json response.
Have created Entity as from your json response:
public class Entity {
private String value;
private String type;
// getters and setters omitted for brevity
}
Finally in your getEntityByUri method have got the instance of UriComponentsBuilder which handles uri encoding and query params.
To sum up, your getEntityByUri looks below.
public HttpEntity<Entity> getEntityByUri() {
String req = "http://live.dbpedia.org/sparql";
UriComponentsBuilder builder = UriComponentsBuilder.fromHttpUrl(req)
.queryParam("query",
"DESCRIBE <http://dbpedia.org/resource/Concept_learning>")
.queryParam("format", "application/json-ld");
HttpHeaders headers = new HttpHeaders();
headers.setAccept(Arrays.asList(MediaType.ALL));
HttpEntity<String> httpEntity = new HttpEntity<String>(headers);
return new RestTemplate().exchange(builder.build().encode().toUri(), HttpMethod.GET, httpEntity, Entity.class);
}
The above method didn't throw HTTP400 as the required query params have been passed in builder object.
Hope this helps and good luck!
Anyone getting same error make sure your URL is decoded means no percent symbols in url (if space in param values).
This worked for me
try {
requestURL = URLDecoder.decode("http://api.com?p=1&groups=3212&affected-since=2019-06-06T14%3A11%3A14.880&detail=full&after-id=43536", "UTF-8");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
Maybe
headers.setAccept(Arrays.asList(MediaType.ALL));
generates a malformed "Accept" header field? (FWIW, why do you send it at all???)