Overview: I am going to use RestTemplate to invoke a get request from external REST webservice.
My code is as follows:
@Slf4j
@Component("AccMemberDetailsApiControllerImpl")
public class AccMemberDetailsApiControllerImpl implements MemberDetailsApiController {
private static final String CONTENT_TYPE_HEADER_NAME = "Content-Type";
private static final String AUTHORIZATION_HEADER_NAME = "Authorization";
private static final String USERID_PARAMETER_NAME = "userId";
private static final String VEHICLEID_PARAMETER_NAME = "vehicleId";
private static final ObjectMapper mapper = new ObjectMapper();
/**
* This constant is used to check whether or not the response from ACC is an empty JSON string
*/
private static final String EMPTY_RESPONSE = "{}";
@Value("${com.blss.memberServices.provider.posServiceURL}")
private String accPosServiceURL;
@Autowired
private RestTemplate restTemplate;
@Autowired
private AccTokenUtility accTokenUtility;
@Autowired
private ResourceMessage resourceMessage;
void setAccTokenUtility(AccTokenUtility accTokenUtility) {
this.accTokenUtility = accTokenUtility;
}
void setResourceMessage(ResourceMessage resourceMessage) {
this.resourceMessage = resourceMessage;
}
/**
* @see MemberDetailsApiController#getMemberDetails(String, String)
*/
@Override
public MemberDetailsModel getMemberDetails(String storeId, String membershipIdentifier) {
/**
* Getting CAD token
*/
String token = accTokenUtility.getCadToken();
/**
* Preparing the request
*/
HttpHeaders headers = new HttpHeaders();
// headers.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));
headers.set(CONTENT_TYPE_HEADER_NAME, MediaType.APPLICATION_JSON_VALUE);
headers.set(AUTHORIZATION_HEADER_NAME, token);
HttpEntity<String> entity = new HttpEntity<>(headers);
/**
* Creating the dispatch URL by means of userId and vehicleId
*/
String dispatchURL = accPosServiceURL + "DispatchedEvent/{userId}/{vehicleId}";
/**
* Creating the URL variables and being valued by corresponding method parameters
*/
Map<String, String> parameters = new HashMap<>();
// parameters.put(USERID_PARAMETER_NAME, storeId);
parameters.put(USERID_PARAMETER_NAME, "mr2");
// parameters.put(VEHICLEID_PARAMETER_NAME, membershipIdentifier);
parameters.put(VEHICLEID_PARAMETER_NAME, "VEH1");
/**
* Calling the rest webservice and returning response with body of type {@link AccMemberDetails}
*/
ResponseEntity<String> response;
MemberDetailsModel memberDetailsModel = null;
AccMemberDetails accMemberDetails;
try {
response = restTemplate.exchange(dispatchURL, HttpMethod.GET, entity, String.class, parameters);
if (response == null || StringUtils.isBlank(response.getBody()) || EMPTY_RESPONSE.equals(response.getBody())) {
throw new ResourceNotFoundException(resourceMessage.getMessage(MEMBER_ERROR_NOT_FOUND, storeId, membershipIdentifier));
} else {
accMemberDetails = deserialize(response.getBody(), AccMemberDetails.class);
String accErrorMessage = accMemberDetails.getUserMessage();
if (!StringUtils.isBlank(accErrorMessage)) {
throw new InternalServerException(resourceMessage.getMessage(MEMBER_ERROR_MESSAGE_FROM_API, "ACC", accErrorMessage));
}
memberDetailsModel = convert(accMemberDetails);
}
} catch (RestClientException e) {
handleExceptions(e, storeId, membershipIdentifier);
}
return memberDetailsModel;
}
/**
* This method is responsible for deserializing string REST response into an object of type {@link AccMemberDetails}
*/
<T> T deserialize(final String response, final Class<T> responseClass) {
try {
return mapper.readValue(response, responseClass);
} catch (IOException e) {
throw new InternalServerException(resourceMessage.getMessage(MEMBER_ERROR_MAP_RESPONSE_OBJECT), e);
}
}
/**
* This method is responsible for converting an instance of type {@link AccMemberDetails} to an instance of type
* {@link MemberDetailsModel}
*
* @param accMemberDetails an instance of type {@link AccMemberDetails}
* @return an instance of type {@link MemberDetailsModel}
*/
MemberDetailsModel convert(AccMemberDetails accMemberDetails) {
MemberDetailsModel memberDetailsModel = new MemberDetailsModel();
memberDetailsModel.setEventId(accMemberDetails.getEventId());
memberDetailsModel.setMemberName(accMemberDetails.getMemberName());
memberDetailsModel.setMembershipNumber(accMemberDetails.getMembershipNumber());
memberDetailsModel.setMembershipLevel(accMemberDetails.getPricingLevel());
return memberDetailsModel;
}
/**
* This method is responsible for handling Exceptions may be thrown by ACC REST webservice
*
* @param e an instance of type {@link RestClientException}
* @param storeId an instance of type {@link String} and used in building exception messages
* @param membershipIdentifier an instance of type {@link String} and used in building exception messages
*/
private void handleExceptions(RestClientException e, String storeId, String membershipIdentifier) {
if (e instanceof HttpStatusCodeException) {
HttpStatusCodeException httpStatusCodeException = (HttpStatusCodeException) e;
HttpStatus httpStatusCode = httpStatusCodeException.getStatusCode();
if (404 == httpStatusCode.value()) {
throw new ResourceNotFoundException(resourceMessage.getMessage(MEMBER_ERROR_NOT_FOUND, storeId, membershipIdentifier), e);
} else if (500 == httpStatusCode.value()) {
throw new InternalServerException(resourceMessage.getMessage(MEMBER_SERVER_ERROR, "ACC"), e);
} else {
throw new InternalServerException(resourceMessage.getMessage(MEMBER_HTTP_STATUS_CODE_ERROR, "HttpStatusCodeException", "ACC"), e);
}
} else {
throw new InternalServerException(resourceMessage.getMessage(MEMBER_REST_CLIENT_ERROR, "RestClientException", "ACC"), e);
}
}
Problem
However I got UnhandledHttpStatusException after calling "restTemplate.exchange(dispatchURL, HttpMethod.GET, entity, String.class, parameters);" in the code snippet. the exception stack trace is as follows:
Caused by: org.springframework.web.client.UnknownHttpStatusCodeException: Unknown status code [443] null
at org.springframework.web.client.DefaultResponseErrorHandler.getHttpStatusCode(DefaultResponseErrorHandler.java:60)
at org.springframework.web.client.DefaultResponseErrorHandler.hasError(DefaultResponseErrorHandler.java:50)
at org.springframework.web.client.RestTemplate.handleResponse(RestTemplate.java:629)
at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:597)
at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:565)
at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:484)
at com.blss.retailServices.memberServices.controllers.impl.acc.AccMemberDetailsApiControllerImpl.getMemberDetails(AccMemberDetailsApiControllerImpl.java:110)
Now I would be grateful if anyone could suggest me a solution.
I called this webservice with curl by using "-v" in order to get more info in response. As a result, I got the same exception (443) from their side. So, It sounds like they should have a better exception handler to return meaningful exception messages.