We Keep Coding

FIXED Send POST request to server from client, Springboot

I am trying to send a post request, but springboot doesnt seem to recieve it.
My code:
Serverside reader
#RestController
public class MessageService {
#PostMapping(path = "/online")
public ResponseEntity<?> getResponse(){
System.out.println("Post Recieved");
return new ResponseEntity<>(HttpStatus.OK);
}
}
Client
private String url = "http://127.0.0.1:8090";
public static void main(String[] args) throws IOException {
SpringApplication.run(Client.class, args);
new StartupService().init();
}
public String getUrl() {
return url;
}
public void setUrl(String url) {
this.url = url;
}
StartupService/ POST Sender
public void init() throws IOException {
String query = "Body";
Client client = new Client();
HttpURLConnection urlConn;
URL mUrl = new URL(client.getUrl()+ "/online");
urlConn = (HttpURLConnection) mUrl.openConnection();
//query is body
urlConn.addRequestProperty("Content-Type", "application/" + "POST");
urlConn.setDoOutput(true);
urlConn.setRequestProperty("Content-Length", Integer.toString(query.length()));
urlConn.getOutputStream().write(query.getBytes(StandardCharsets.UTF_8));
System.out.println("Post Sent");
}
I tried sending a POST request via Postman, which worked as expected and gave me the console output. But the POST from code isn't recieved from the server.

FIXED: I used a simpler method to send a POST:
javaClient userClient = new Client();
HttpClient client = HttpClient.newHttpClient();
HttpRequest request = HttpRequest.newBuilder()
.uri(URI.create(userClient.getUrl()+ "/online"))
.POST(HttpRequest.BodyPublishers.ofString(query))
.build();
HttpResponse<String> response = client.send(
request,
HttpResponse.BodyHandlers.ofString()
);
System.out.println(response.body());
System.out.println("Post Sent");

Send HTTPS request with JSON through Java [duplicate]

I would like to make a simple HTTP POST using JSON in Java.
Let's say the URL is www.site.com
and it takes in the value {"name":"myname","age":"20"} labeled as 'details' for example.
How would I go about creating the syntax for the POST?
I also can't seem to find a POST method in the JSON Javadocs.

Here is what you need to do:
Get the Apache HttpClient, this would enable you to make the required request
Create an HttpPost request with it and add the header application/x-www-form-urlencoded
Create a StringEntity that you will pass JSON to it
Execute the call
The code roughly looks like (you will still need to debug it and make it work):
// #Deprecated HttpClient httpClient = new DefaultHttpClient();
HttpClient httpClient = HttpClientBuilder.create().build();
try {
HttpPost request = new HttpPost("http://yoururl");
StringEntity params = new StringEntity("details={\"name\":\"xyz\",\"age\":\"20\"} ");
request.addHeader("content-type", "application/x-www-form-urlencoded");
request.setEntity(params);
HttpResponse response = httpClient.execute(request);
} catch (Exception ex) {
} finally {
// #Deprecated httpClient.getConnectionManager().shutdown();
}

You can make use of Gson library to convert your java classes to JSON objects.
Create a pojo class for variables you want to send
as per above Example
{"name":"myname","age":"20"}
becomes
class pojo1
{
String name;
String age;
//generate setter and getters
}
once you set the variables in pojo1 class you can send that using the following code
String postUrl = "www.site.com";// put in your url
Gson gson = new Gson();
HttpClient httpClient = HttpClientBuilder.create().build();
HttpPost post = new HttpPost(postUrl);
StringEntity postingString = new StringEntity(gson.toJson(pojo1));//gson.tojson() converts your pojo to json
post.setEntity(postingString);
post.setHeader("Content-type", "application/json");
HttpResponse response = httpClient.execute(post);
and these are the imports
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.HttpClientBuilder;
and for GSON
import com.google.gson.Gson;

#momo's answer for Apache HttpClient, version 4.3.1 or later. I'm using JSON-Java to build my JSON object:
JSONObject json = new JSONObject();
json.put("someKey", "someValue");
CloseableHttpClient httpClient = HttpClientBuilder.create().build();
try {
HttpPost request = new HttpPost("http://yoururl");
StringEntity params = new StringEntity(json.toString());
request.addHeader("content-type", "application/json");
request.setEntity(params);
httpClient.execute(request);
// handle response here...
} catch (Exception ex) {
// handle exception here
} finally {
httpClient.close();
}

It's probably easiest to use HttpURLConnection.
http://www.xyzws.com/Javafaq/how-to-use-httpurlconnection-post-data-to-web-server/139
You'll use JSONObject or whatever to construct your JSON, but not to handle the network; you need to serialize it and then pass it to an HttpURLConnection to POST.

protected void sendJson(final String play, final String prop) {
Thread t = new Thread() {
public void run() {
Looper.prepare(); //For Preparing Message Pool for the childThread
HttpClient client = new DefaultHttpClient();
HttpConnectionParams.setConnectionTimeout(client.getParams(), 1000); //Timeout Limit
HttpResponse response;
JSONObject json = new JSONObject();
try {
HttpPost post = new HttpPost("http://192.168.0.44:80");
json.put("play", play);
json.put("Properties", prop);
StringEntity se = new StringEntity(json.toString());
se.setContentType(new BasicHeader(HTTP.CONTENT_TYPE, "application/json"));
post.setEntity(se);
response = client.execute(post);
/*Checking response */
if (response != null) {
InputStream in = response.getEntity().getContent(); //Get the data in the entity
}
} catch (Exception e) {
e.printStackTrace();
showMessage("Error", "Cannot Estabilish Connection");
}
Looper.loop(); //Loop in the message queue
}
};
t.start();
}

Try this code:
HttpClient httpClient = new DefaultHttpClient();
try {
HttpPost request = new HttpPost("http://yoururl");
StringEntity params =new StringEntity("details={\"name\":\"myname\",\"age\":\"20\"} ");
request.addHeader("content-type", "application/json");
request.addHeader("Accept","application/json");
request.setEntity(params);
HttpResponse response = httpClient.execute(request);
// handle response here...
}catch (Exception ex) {
// handle exception here
} finally {
httpClient.getConnectionManager().shutdown();
}

I found this question looking for solution about how to send post request from java client to Google Endpoints. Above answers, very likely correct, but not work in case of Google Endpoints.
Solution for Google Endpoints.
Request body must contains only JSON string, not name=value pair.
Content type header must be set to "application/json".
post("http://localhost:8888/_ah/api/langapi/v1/createLanguage",
"{\"language\":\"russian\", \"description\":\"dsfsdfsdfsdfsd\"}");
public static void post(String url, String json ) throws Exception{
String charset = "UTF-8";
URLConnection connection = new URL(url).openConnection();
connection.setDoOutput(true); // Triggers POST.
connection.setRequestProperty("Accept-Charset", charset);
connection.setRequestProperty("Content-Type", "application/json;charset=" + charset);
try (OutputStream output = connection.getOutputStream()) {
output.write(json.getBytes(charset));
}
InputStream response = connection.getInputStream();
}
It sure can be done using HttpClient as well.

You can use the following code with Apache HTTP:
String payload = "{\"name\": \"myname\", \"age\": \"20\"}";
post.setEntity(new StringEntity(payload, ContentType.APPLICATION_JSON));
response = client.execute(request);
Additionally you can create a json object and put in fields into the object like this
HttpPost post = new HttpPost(URL);
JSONObject payload = new JSONObject();
payload.put("name", "myName");
payload.put("age", "20");
post.setEntity(new StringEntity(payload.toString(), ContentType.APPLICATION_JSON));

For Java 11 you can use the new HTTP client:
HttpClient client = HttpClient.newHttpClient();
HttpRequest request = HttpRequest.newBuilder()
.uri(URI.create("http://localhost/api"))
.header("Content-Type", "application/json")
.POST(ofInputStream(() -> getClass().getResourceAsStream(
"/some-data.json")))
.build();
client.sendAsync(request, BodyHandlers.ofString())
.thenApply(HttpResponse::body)
.thenAccept(System.out::println)
.join();
You can use publishers from InputStream, String, File. Converting JSON to a String or IS can be done with Jackson.

Java 11 standardization of HTTP client API that implements HTTP/2 and Web Socket, and can be found at java.net.HTTP.*:
String payload = "{\"name\": \"myname\", \"age\": \"20\"}";
HttpClient client = HttpClient.newHttpClient();
HttpRequest request = HttpRequest.newBuilder(URI.create("www.site.com"))
.header("content-type", "application/json")
.POST(HttpRequest.BodyPublishers.ofString(payload))
.build();
HttpResponse<String> response = client.send(request, BodyHandlers.ofString());

Java 8 with apache httpClient 4
CloseableHttpClient client = HttpClientBuilder.create().build();
HttpPost httpPost = new HttpPost("www.site.com");
String json = "details={\"name\":\"myname\",\"age\":\"20\"} ";
try {
StringEntity entity = new StringEntity(json);
httpPost.setEntity(entity);
// set your POST request headers to accept json contents
httpPost.setHeader("Accept", "application/json");
httpPost.setHeader("Content-type", "application/json");
try {
// your closeablehttp response
CloseableHttpResponse response = client.execute(httpPost);
// print your status code from the response
System.out.println(response.getStatusLine().getStatusCode());
// take the response body as a json formatted string
String responseJSON = EntityUtils.toString(response.getEntity());
// convert/parse the json formatted string to a json object
JSONObject jobj = new JSONObject(responseJSON);
//print your response body that formatted into json
System.out.println(jobj);
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
}
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}

I recomend http-request built on apache http api.
HttpRequest<String> httpRequest = HttpRequestBuilder.createPost(yourUri, String.class)
.responseDeserializer(ResponseDeserializer.ignorableDeserializer()).build();
public void send(){
ResponseHandler<String> responseHandler = httpRequest.execute("details", yourJsonData);
int statusCode = responseHandler.getStatusCode();
String responseContent = responseHandler.orElse(null); // returns Content from response. If content isn't present returns null.
}
If you want send JSON as request body you can:
ResponseHandler<String> responseHandler = httpRequest.executeWithBody(yourJsonData);
I higly recomend read documentation before use.

Apache HttpClient 4.5 redirect POST request to GET request

Am traying to hit a post endpoint but It is giving error 302, When I tried another get Url on the same server it gives me 200. Then I redirected the post request using LaxRedirectStrategy() The post request is redirecting to the get request(same endpoint only method name is GET and POST) it is not getting response from the post method. Can anyone tell me how to redirect post request to post request using apahce httpClient 4.5
HttpClient client= HttpClientBuilder.create()
.setRedirectStrategy(new LaxRedirectStrategy()).build();
HttpPost post = new HttpPost("url");
post.addHeader("content-type", " application/json");
HttpResponse response = client.execute(post);

I had the same issue I solved it by using using LaxRedirectStrategy with overridden getRedirect method.
Apparently the default behaviour for POST requests is to make the redirected call as a GET request when the initial redirect response is different than 307 or 308.
See:
DefaultRedirectStrategy which LaxRedirectStrategy inherits from.
In my case the redirect response code was a 302.
So if you want something different, you can just override the getRedirect method and provide your own implementation.
Something like:
new LaxRedirectStrategy() {
#Override
public HttpUriRequest getRedirect(HttpRequest request, HttpResponse response, HttpContext context) throws ProtocolException {
final URI uri = getLocationURI(request, response, context);
final String method = request.getRequestLine().getMethod();
if (method.equalsIgnoreCase(HttpHead.METHOD_NAME)) {
return new HttpHead(uri);
} else if (method.equalsIgnoreCase(HttpGet.METHOD_NAME)) {
return new HttpGet(uri);
} else {
final int status = response.getStatusLine().getStatusCode();
if (status == HttpStatus.SC_TEMPORARY_REDIRECT || status == HttpStatus.SC_MOVED_TEMPORARILY) { //HttpStatus.SC_MOVED_TEMPORARILY == 302
return RequestBuilder.copy(request).setUri(uri).build();
} else {
return new HttpGet(uri);
}
}
}
}

HttpClient httpClient =
HttpClients.custom().setRedirectStrategy(new LaxRedirectStrategy() {
/*
* (non-Javadoc)
*
* #see org.apache.http.impl.client.DefaultRedirectStrategy#
* getRedirect(org.apache.http.HttpRequest,
* org.apache.http.HttpResponse,
* org.apache.http.protocol.HttpContext)
*/
#Override
public HttpUriRequest getRedirect(
HttpRequest request, HttpResponse response,
HttpContext context) throws ProtocolException
{
final URI uri = getLocationURI(request, response, context);
final String method = request.getRequestLine().getMethod();
if (method.equalsIgnoreCase(HttpPost.METHOD_NAME)) {
HttpPost post = new HttpPost(uri);
post.setEntity(entity);
return post;
} else if (method.equalsIgnoreCase(HttpHead.METHOD_NAME)) {
return new HttpHead(uri);
} else if (method.equalsIgnoreCase(HttpGet.METHOD_NAME)) {
return new HttpGet(uri);
} else {
final int status =
response.getStatusLine().getStatusCode();
return status == HttpStatus.SC_TEMPORARY_REDIRECT
? RequestBuilder.copy(request).setUri(uri).build()
: new HttpGet(uri);
}
}
})

Empty request when sending special characters to API with Java

I'm using Java to send http requests to my API which is created using Laravel (5.4). If I send a request without any special characters it all works like a charm. But if there are any 'special' characters like: é, å, ö and such the request in Laravel is empty:
dd(request()->all()) outputs []
I guess this has to do with some wrong settings while creating the request in Java. I couldn't find a solution.
Here is the code responsible for creating the request.
public class HttpClient {
org.apache.http.client.HttpClient client;
public HttpClient() {
client = HttpClientBuilder.create().build();
}
public void post(String json) {
try {
HttpPost request = buildPostRequest(json);
HttpResponse response = createClient().execute(request);
int code = getStatusCode(response);
if (code != 200) {
throw new Exception("Error (" + code + ") on server.");
}
} catch (Exception e) {
System.out.println(e.getMessage());
}
}
private org.apache.http.client.HttpClient createClient() {
return HttpClientBuilder.create().build();
}
private HttpPost buildPostRequest(String json) throws Exception {
HttpPost request = new HttpPost("some uri");
request.addHeader("Content-type", "application/json; charset=utf-8");
request.addHeader("Accept", "application/json");
StringEntity params = new StringEntity(json);
params.setContentEncoding("utf-8");
params.setContentType("application/json; charset=utf-8");
request.setEntity(params);
return request;
}
private int getStatusCode(HttpResponse response) {
StatusLine line = response.getStatusLine();
return line.getStatusCode();
}
}
EDIT
Dump of the request before it get's send to the API.

I found a solution to the problem. In the buildPostRequest() method I changed from a StringEntity to a ByteArrayEntity and coverted the string to UTF-8 bytes.
ByteArrayEntity params = new ByteArrayEntity(json.getBytes("UTF-8"));
If I send special characters to the API the request isn't empty anymore.

try this way
HttpPost request = new HttpPost(URLEncoder.encode("url here", "UTF-8"));

authentication with Java and apache HttpClient 4.5.1

my problem is, that i don't get, how to log in with Java and Apache HttpComponents (HttpClient v4.5.1) into a specific site: Site im trying to log in. I have the username (test_admin) and the password (testing) to log in but i think this is not enough and i need something more. I think this has something to do with the field security_token i see when i make a get request to the uri, but i dont know how to keep that or how to save that and what to do with it afterwards. There is also a hidden input field with the name login-ticket, but i dont know what's that for either. I want to login, because i need to see the courses and add some new ones. After trying with several code implementations im stick with this code:
public static void setGet(CloseableHttpClient httpClient) throws UnsupportedOperationException, IOException
{
HttpGet httpGet = new HttpGet("http://demo.studip.de/dispatch.php/admin/courses");
CloseableHttpResponse httpResponse = httpClient.execute(httpGet);
System.out.println("GET Response Status:: "
+ httpResponse.getStatusLine().getStatusCode());
showEntity(httpResponse,httpResponse.getEntity());
}
public static HttpEntity setParam(int count, String[] params, String[] values)
{
List<NameValuePair> formparams = new ArrayList<NameValuePair>();
for (int i = 0; i < count; i++)
{
formparams.add(new BasicNameValuePair(params[i],values[i]));
System.out.println("Paramater------------------> "+params[i]+" Values-------------> "+values[i]);
}
UrlEncodedFormEntity entity = new UrlEncodedFormEntity(formparams, Consts.UTF_8);
return entity;
}
public static void setPost(HttpClient httpC) throws ClientProtocolException, IOException
{
HttpPost httppost = new HttpPost("http://demo.studip.de/dispatch.php/admin/courses");
//String[] params = {"loginname", "password"};
//String[] values = {"test_admin", "testing"};
//HttpEntity entity = setParam(2, params, values );
HttpResponse response = httpC.execute(httppost);
System.out.println("POST Response Status:: "
+ response.getStatusLine().getStatusCode());
showEntity(response, response.getEntity());
}
public static void showEntity(HttpResponse httpResp, HttpEntity httpClient) throws IOException
{
httpClient = httpResp.getEntity();
if (httpClient != null)
httpClient = new BufferedHttpEntity(httpClient);
System.out.print(EntityUtils.toString(httpClient));
}
public static void main(String[] args) throws InterruptedException, IOException {
CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
credentialsProvider.setCredentials(AuthScope.ANY,
new UsernamePasswordCredentials("test_admin", "testing"));
CloseableHttpClient hc =
HttpClientBuilder.create().setDefaultCredentialsProvider(credentialsProvider).build();
setGet(hc);
// HttpClient httpclient = HttpClients.createDefault();
setPost(hc);
setGet(hc);
}
The problem now ist that i get everytime the same answer from the server i only see the login page in the response, where the server asks me to login with username and password.

Which code you get from the server 401,403,301,302 or 200?