How to use Spring RestTemplate instead of Apache Httpclient? - java

I want to use Spring RestTemplate instead of Apache HttpClient for working with a remote API
With HttpClient
// build request JSON
JSONObject json = new JSONObject();
json.put("username", username);
json.put("serial", serial);
json.put("keyId", keyId);
json.put("otp", otp);
String json_req = json.toString();
// make HTTP request and get response
HttpPost request = new HttpPost(AuthServer);
request.setHeader("Content-Type", "application/json");
request.setEntity(new StringEntity(json_req));
response = client.execute(request);
With RestTemplate
Map<String, String> paramMap = new HashMap<String,String>();
paramMap.put("username", userName);
paramMap.put("serial", serial);
paramMap.put("keyId", keyId);
paramMap.put("otp", otp);
String mapAsJson = new ObjectMapper().writeValueAsString(paramMap);
HttpHeaders requestHeaders = new HttpHeaders();
requestHeaders.setContentType(MediaType.APPLICATION_JSON);
HttpEntity<String> request = new HttpEntity<String>(mapAsJson,requestHeaders);
try {
ResponseEntity<String> response = restTemplate.exchange(AuthServer, HttpMethod.POST, request, String.class);
return response.getHeaders();
} catch (HttpClientErrorException e) {
return null;
}
}
The code with HttpClient works but that with RestTemplate does not. I don't know how to use StringEntity in RestTemplate.
Spring version is 3.0.0, and JVM is 1.6.

RestTemplate is better suited to working with objects. As an example:
AuthenticationRequest.java
class AuthenticationRequest {
private String username;
private String serial;
private String key;
private String otp;
}
AuthenticationResponse.java
class AuthenticationResponse {
private boolean success;
}
AuthenticationCall.java
class AuthenticationCall {
public AuthenticationResponse execute(AuthenticationRequest payload) {
HttpEntity<AuthenticationRequest> request = new HttpEntity<AuthenticationRequest>(payload, new HttpHeaders());
return restTemplate.exchange("http://www.domain.com/api/endpoint"
, HttpMethod.POST
, request
, AuthenticationResponse.class).getBody();
}
}
These classes can be used as follows:
if(new AuthenticationCall().execute(authenticationRequest).isSuccess()) {
// Authentication succeeded.
}
else {
// Authentication failed.
}
All of this requires there to be a JSON library such as Jackson or GSON on the classpath.

Related

How to sent Http POST request with application/x-www-form-urlencoded

I'm trying to generate a token from an external website, the post request must be application/x-www-form-urlencoded but I'm getting errors. I assume that I'm not making the right call for the content type application/x-www-form-urlencoded but I can't figuer out how!!
PS: I'm using springboot with java 8
here is the code:
public String getNewAccesToken() {
//Initilazing variabels
try {
JsonObject properties = new JsonObject();
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.APPLICATION_FORM_URLENCODED);
headers.set("Cookie", cookie);
properties.addProperty("client_id", clientId);
properties.addProperty("client_secret", clientSecret);
properties.addProperty("grant_type", grantType);
HttpEntity<String> requestEntity = new HttpEntity<>(properties.toString(), headers);
log.debug(requestEntity);
ResponseEntity<String> response = restTemplate.exchange(requestUrl, HttpMethod.POST, requestEntity,
String.class);
log.debug("---------------------------------");
log.debug(response);
if (Util.isJSONValid(response.getBody())) {
JsonParser parser = new JsonParser();
JsonObject jsonString = (JsonObject) parser.parse(response.getBody());
return jsonString.get("accessToken").getAsString();
} else {
error.setCode(ConstantGateway.JSON_ERROR_CODE);
error.setMessage(ConstantGateway.JSON_ERROR_STATUS);
return error.toString();
}
} catch (HttpStatusCodeException e) {
error.setCode(String.valueOf(e.getStatusCode().value()));
error.setMessage(e.getResponseBodyAsString());
return error.toString();
} catch (Exception e) {
// TODO: handle exception
error.setCode(ConstantGateway.IL_INTERNAL_ERROR_CODE);
error.setMessage(e.getMessage());
return error.toString();
}
}
and here is what I get when calling this function:
org.zwz.vas.internal.api.model.ErrorModel#16dd359c
However when I make the call from Postman I get the right response which is :
{
"access_token": "RdWt3DNIfxmihnubGX0Fgfcb0KNHLZV79OfN9Y6Ky6Z3fxAfF_Pm7uP0jnFrG1fHplyBMZ74BIKleQ8jmswdGy4e87NV-uZsMzgS1nQAONc2nBxgU1_jkMBhL4vvIniJNd99oYNzGeanCYYki0yorrrlLrOGTncusv1BgFFHU_CBGuUtGmZYLfJAJW4XcZLhXMC9xpT2aWAvgRXZW69pOhfU1Fgs7aVwou85UVI2b4j1GfX0pCtJtluiTgXsuWqdck7_at1dqfopHpjWAywYrweStMXGm8T59nyQi_oXWmo",
"token_type": "bearer",
"expires_in": 1199
}
THANK YOU IN ADVANCE
I find the mistake I did, I was sending a wrong request format which is not compatibale with application/x-www-form-urlencoded type. The right code is below:
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.APPLICATION_FORM_URLENCODED);
headers.set("Cookie", cookie);
MultiValueMap<String, String> properties= new LinkedMultiValueMap<String, String>();
properties.add("client_id", clientId);
properties.add("client_secret", clientSecret);
properties.add("grant_type", grantType);
HttpEntity<MultiValueMap<String, String>> request = new HttpEntity<MultiValueMap<String, String>>(properties, headers);
ResponseEntity<String> response = restTemplate.postForEntity( requestUrl, request , String.class );

How to fetch data from http response entity?

I am using SpringBoot to fetch access Token from my client. I could not separate the Access Token from the responseEntity. Is there a way to Fetch the AccessToken data alone?
Here is the code:
public ResponseEntity generate_Access_token() {
String url = "https://zoom.us/oauth/token";
RestTemplate restTemplate = new RestTemplate();
HttpHeaders headers = new HttpHeaders();
final Gson gson = new Gson();
headers.setContentType(MediaType.APPLICATION_FORM_URLENCODED);
MultiValueMap<String, String> map= new LinkedMultiValueMap<String, String>();
map.add("grant_type", "account_credentials");
map.add("client_id", "XXX");
map.add("client_secret", "XXX");
map.add("account_id", "XXX");
HttpEntity<MultiValueMap<String, String>> request = new HttpEntity<MultiValueMap<String, String>>(map, headers);
ResponseEntity<String> response = restTemplate.postForEntity( url, request , String.class );
//ResponseEntity<String> response_data=new ResponseEntity<String>(response.toString(), HttpStatus.CREATED);
ResponseEntity<AccessTokenResponse> response_data = restTemplate.postForEntity( url, request , AccessTokenResponse.class );
return response_data.getAccessToken();
}
class AccessTokenResponse{
#JsonProperty("access_token")
String accessToken;
//other props you are interested in
//+ getters/setters
public String getAccessToken() {
return accessToken;
}
public void setAccessToken(String accessToken) {
this.accessToken = accessToken;
}
}
}
The response:
{
"access_token": "eyJhbGciOiJIUzUxMiIsInYiOiIyLjAiLCJraWQiOiJlNDI1NDFkYi0zMTllLTRiMGYtOWIwMC04YTVlZmY4NTI2NTAifQ.eyJ2ZXIiOjcsImF1aWQiOiJjNWFjZThhNGRiNDY0NTJhM2YxNGNkZjcyZjY1MjU2NSIsImNvZGUiOiIxYldicXNVNVR3V1hDUEY5M2ZTbjdBR21xT1NKOXBUS0kiLCJpc3MiOiJ6bTpjaWQ6NjFtN2ppSXFUM2VMWDRuS0xZVUdGZyIsImdubyI6MCwidHlwZSI6MywiYXVkIjoiaHR0cHM6Ly9vYXV0aC56b29tLnVzIiwidWlkIjoianYwWWZyUDlRLWFLTlctTFVlSXRDZyIsIm5iZiI6MTY1NjMxNzM2MiwiZXhwIjoxNjU2MzIwOTYyLCJpYXQiOjE2NTYzMTczNjIsImFpZCI6IkJ4MnVOWHpHUWwtSHVDN3BITWF2NWciLCJqdGkiOiJlYTYwMDkwYS0wMWY1LTQwODctODgxMi0wNmQ2Mzk1NTI2ZGUifQ.nKiYXxCDbhQRsyR2pTu0nwegQKBHsSR9JT7CBnad5pPfBi4pVBISjGp6icRv2Nyv_L7lNzVBK8clW7Z5zM9TUg",
"token_type": "bearer",
"expires_in": 3599,
"scope": "meeting:read:admin user:master user:read:admin user:write:admin"
}
Make your life easier, not harder - use plain DTO
class AccessTokenResponse{
#JsonProperty("access_token");
String accessToken
//other props you are interested in
//+ getters/setters
}
and then
AccessTokenResponse response = restTemplate.postForObject( url, request , AccessTokenResponse.class );
response.getAccessToken(); //here you have it

Authorization for Google Drive Push Notifications for Java

I am trying to get push notifications from a resource on Google Drive to my server. I have been looking at this example:
https://developers.google.com/drive/v3/web/push
And I have tried translating that to Java into something like this:
RestTemplate restTemplate = new RestTemplate();
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.APPLICATION_JSON);
MultiValueMap<String, String> map = new LinkedMultiValueMap<String, String>();
map.add("id", "36d00d08-000d-4723-91bc-a1a6ec302e59");
map.add("type", "web_hook");
map.add("address", "https://mydomain.appspot.com/rest/drive");
HttpEntity<MultiValueMap<String, String>> request = new HttpEntity<MultiValueMap<String, String>>(map, headers);
ResponseEntity<String> response = restTemplate.postForEntity(uri, request, String.class);
I have previously been using Googles libs for Drive to access files. In those cases I didn't need to create the request in such a "manual" way. I have used the class GoogleAuthorizationCodeFlow with a token to authorize my requests. I'm not sure how I should do that with RestTemplate. I am guessing that I need to do something like:
headers.set("Authorization", X);
What should X be here? Is that even the right way to approach authorization?
Edit:
Here is my attempt by reading a secret. The result is HTTP 401:
#Override
public String startListening() throws IOException {
final String fileId = "omitted";
String uri = "https://www.googleapis.com/drive/v3/files/" + fileId + "/watch";
HttpHeaders headers = getHeaders(getSecret());
HttpEntity<MultiValueMap<String, String>> request = new HttpEntity<MultiValueMap<String, String>>(getProperties(), headers);
RestTemplate restTemplate = new RestTemplate();
ResponseEntity<String> response = restTemplate.postForEntity(uri, request, String.class);
return response.getStatusCode() + " " + response.getBody() + " " + response.getHeaders();
}
private static HttpHeaders getHeaders(String theString) {
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.APPLICATION_JSON);
headers.set("Authorization", "Bearer " + theString);
return headers;
}
private static MultiValueMap<String, String> getProperties() {
MultiValueMap<String, String> map = new LinkedMultiValueMap<String, String>();
map.add("id", "some uid");
map.add("type", "web_hook");
map.add("address", "https://mydomain.appspot.com/rest/drive");
return map;
}
private static String getSecret() throws IOException {
InputStream in =
ConcreteDriveListenerFactory.class.getResourceAsStream("/drive_secret.json");
StringWriter writer = new StringWriter();
IOUtils.copy(in, writer, "UTF-8");
return writer.toString();
}
As #DalmTo has mentioned, X is for token. With regard to sample POST request for Drive API try this code snippet from this SO thread. It also uses a POST method.
public static void main(String argv[]) throws Exception {
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost post = new HttpPost(
"https://www.googleapis.com/drive/v2/files");
post.addHeader("Content-Type", "application/json");
post.addHeader("Authorization",
"Bearer XXXXXXXXXXXXXXXXXXXXXXXXX");
JsonObject jsonObject = new JsonObject();
jsonObject.addProperty("title", "Test folder");
jsonObject
.addProperty("mimeType", "application/vnd.google-apps.folder");
post.setEntity(new StringEntity(jsonObject.toString()));
httpClient.execute(post);
}

How Do I make a HTTP Delete/Update Request?

Right Now I have a Restful Web service called Users.java, That fake adds a user to a fake database
#Path("/users")
public class UsersService {
#POST
public Response handlePost(String requestBody) {
addUserToDatabase(requestBody);
Map<String, Object> jsonMap = new HashMap<>();
jsonMap.put("status", "success");
jsonMap.put("resource-uri", "/users/12"); // assume 12 is the ID of the user we pretended to create
Gson gson = new Gson();
return Response.status(200).entity(gson.toJson(jsonMap)).build();
}
private boolean addUserToDatabase(String requestBody) {
Gson gson = new Gson();
Map<String, String> user = gson.fromJson(requestBody, new TypeToken<Map<String, String>>() {
}.getType());
for (String key : user.keySet()) {
System.out.println(key + ": " + user.get(key));
}
return true; // lie and say we added the user to the database
}
}
it is called using the Post request here, these are examples
public HttpResponse postRequest(String relativePath, Map<String, String> map){
try {
String fullPath = buildURL(relativePath);
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost getRequest = new HttpPost(fullPath);
Gson gson = new Gson();
String postEntity = gson.toJson(map);
getRequest.setEntity(new StringEntity(postEntity));
getRequest.addHeader("accept", "application/json");
HttpResponse response = httpClient.execute(getRequest);
httpClient.getConnectionManager().shutdown();
return response;
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
// POST
Map<String, String> map = new HashMap<>();
map.put("username", "Bill");
map.put("occupation", "Student");
map.put("age", "22");
map.put("DOB", "" + new Date(System.currentTimeMillis()));
HttpResponse response = client.postRequest("/api/users", map);
client.printResponse(response);
Now I want to do something similar with Delete and Update but dont know where to start any help would be great
Use appropriate #Path, #Delete and #Putannotations and implement the methods in a similar way you did for #Post.

Spring restTemplate issue in getting response

My rest server is generating response when I called it with rest client software. When I call it with resttemplate code mentioned above, then server generates response(print logs) but resttemplate does nothing(no next line executes after call) and prints internal error.
This is the method in my server
#ResponseBody
public ResponseEntity<Map<String, Object>> name(){......
...
return new ResponseEntity<Map<String, Object>>(messagebody, HttpStatus.OK);
}
This is the way I am calling it through restTemplate
ResponseEntity<Map> response1 = restTemplate.getForEntity(finalUrl.toString(), Map.class);
Try to use ParameterizedTypeReference instead of wildcarded Map.
It should looks like this.
ParameterizedTypeReference<Map<String, Object>> typeRef = new ParameterizedTypeReference<Map<String, Object>>() {};
ResponseEntity<Map<String, Object>> response = restTemplate.exchange(finalUrl.toString(), HttpMethod.GET, null, typeRef);
this is a example that works for me
#RequestMapping(value = "/getParametros/{instancia}", method = RequestMethod.GET, produces = MediaType.TEXT_PLAIN_VALUE)
public ResponseEntity<String> getParametros(#PathVariable String instancia)
{
LOG.debug("REST. Obteniendo parametros del servidor " + instancia);
Map<String, String> mapa = parametrosService.getProperties(instancia);
HttpHeaders headers = new HttpHeaders();
headers.add("Content-Type", "application/json; charset=UTF-8");
headers.add("X-Fsl-Location", "/");
headers.add("X-Fsl-Response-Code", "302");
ObjectMapper mapper = new ObjectMapper();
String s = "";
try
{
s = mapper.writeValueAsString(mapa);
} catch (JsonProcessingException e)
{
LOG.error("NO SE PUEDE MAPEAR A JSON");
}
if (mapa == null)
return new ResponseEntity<String>(HttpStatus.BAD_REQUEST);
return new ResponseEntity<String>(s, headers, HttpStatus.OK);
}
you can Catch the HttpStatusCodeException from which you can get response in String .
below code works for me.
restTemplate.postForObject( url, jsonRequest, ResponseData.class );
catch( HttpStatusCodeException codeException )
{
String payload = codeException.getResponseBodyAsString();
System.out.println( payload );
}

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