added retry for the send otp

src/main/java/com/billpaymentservice/bbps/exception/GlobalExceptionHandler.java

@@ -6,6 +6,7 @@ import java.util.stream.Collectors;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.http.*;
+import org.springframework.http.converter.HttpMessageNotReadableException;
 import org.springframework.validation.FieldError;
 import org.springframework.web.bind.MethodArgumentNotValidException;
 import org.springframework.web.bind.annotation.*;
@@ -75,6 +76,35 @@ public class GlobalExceptionHandler {
         return ResponseEntity.status(HttpStatus.BAD_REQUEST).body(resp);
     }
 
+    // ------------------------- MALFORMED/INVALID JSON ------------------------
+    @ExceptionHandler(HttpMessageNotReadableException.class)
+    public ResponseEntity<ResponseModel<?>> handleInvalidJson(
+            HttpMessageNotReadableException ex,
+            HttpServletRequest request,
+            HandlerMethod handlerMethod) {
+
+        String endpoint = (request != null) ? request.getMethod() + " " + request.getRequestURI() : "unknown";
+        // prefer the root Jackson message if present
+        String rootMsg = ex.getMostSpecificCause() != null ? ex.getMostSpecificCause().getMessage() : ex.getMessage();
+        String shortMsg = (rootMsg != null && rootMsg.length() > 200) ? rootMsg.substring(0, 200) + "..." : rootMsg;
+
+        logger.warn("Invalid JSON received for endpoint {}: {}", endpoint, shortMsg);
+
+        Map<String, Object> data = Map.of(
+                "exception", ex.getClass().getName(),
+                "message", shortMsg
+        );
+
+        ResponseModel<?> resp = new ResponseModel<>(
+                "[" + endpoint + "] Invalid JSON received",
+                "FAILED",
+                HttpStatus.BAD_REQUEST.value(),
+                data
+        );
+
+        return ResponseEntity.status(HttpStatus.BAD_REQUEST).body(resp);
+    }
+
     // ------------------------- NO HANDLER (404 NOT FOUND) ------------------------
     @ExceptionHandler(NoHandlerFoundException.class)
     public ResponseEntity<ResponseModel<?>> handleNotFound(NoHandlerFoundException ex) {
@@ -121,14 +151,17 @@ public class GlobalExceptionHandler {
         String context = buildErrorContext(ex, request, handlerMethod);
         logger.warn("CustomException → {}", context);
 
-        ResponseModel<?> resp = new ResponseModel<>(
+        // Use the ResponseModel carried by CustomException so callers get the original status/code/data
-                ex.getMessage(),
+        ResponseModel<?> resp = ex.getResponseModel();
-                "FAILED",
-                HttpStatus.BAD_REQUEST.value(),
-                null
-        );
 
-        return ResponseEntity.status(HttpStatus.BAD_REQUEST).body(resp);
+        HttpStatus httpStatus = HttpStatus.BAD_REQUEST;
+        try {
+            httpStatus = HttpStatus.valueOf(resp.getStatusCode());
+        } catch (Exception e) {
+            // fallback
+        }
+
+        return ResponseEntity.status(httpStatus).body(resp);
     }
 
     // ------------------------- GENERIC EXCEPTION ------------------------

src/main/java/com/billpaymentservice/bbps/serviceImpl/AuthServiceImpl.java

@@ -46,7 +46,7 @@ public class AuthServiceImpl implements AuthService {
 
 	@Autowired
 	public AuthServiceImpl(UserRepository userRepository, OtpClient otpClient, Helper helper,
-			UsersDetailsRepository userRepo, JwtUtil jwtUtil) {
+					UsersDetailsRepository userRepo, JwtUtil jwtUtil) {
 		this.userRepository = userRepository;
 		this.otpClient = otpClient;
 		this.helper = helper;
@@ -56,21 +56,18 @@ public class AuthServiceImpl implements AuthService {
 
 	@Override
 	public ResponseModel<?> sendOtp(LoginRequest request) {
-		try {
+		// validate minimal inputs
-			OtpSendResponse resp = otpClient.sendOtp(request.getMobile());
+		if (request == null || request.getMobile() == null || request.getMobile().isBlank()) {
-			if (resp == null) {
+			throw new CustomException("Mobile number is required", "FAILED", 400, "missing mobile");
-				return ResponseModel.builder().message("OTP send service returned null").status("Failure")
-						.statusCode(500).data(null).build();
-			}
-			String status = resp.isSuccess() ? "Success" : "Failure";
-			int code = resp.isSuccess() ? 200 : 400;
-			return ResponseModel.builder().message(resp.getMessage()).status(status).statusCode(code).data(resp)
-					.build();
-		} catch (Exception ex) {
-			LOGGER.error("Error in sendOtp: {}", ex.getMessage(), ex);
-			return ResponseModel.builder().message("An unexpected error occurred while sending OTP").status("Failure")
-					.statusCode(500).data(null).build();
 		}
+
+		// Delegate attempts to helper — it will throw CustomException on unrecoverable issues
+		OtpSendResponse resp = attemptSendOtpWithRetry(request.getMobile(), 1);
+
+		// If the downstream returned a response indicating failure, return that as a ResponseModel
+		String status = resp.isSuccess() ? "Success" : "Failure";
+		int code = resp.isSuccess() ? 200 : 400;
+		return ResponseModel.builder().message(resp.getMessage()).status(status).statusCode(code).data(resp).build();
 	}
 
 	@Override
@@ -121,6 +118,40 @@ public class AuthServiceImpl implements AuthService {
 		}
 	}
 
+	/**
+	 * Helper that attempts to send OTP and retries up to `retryCount` times on null/unsuccessful responses.
+	 * Throws CustomException when the OTP service returns null after retries or when unexpected errors occur.
+	 */
+	private OtpSendResponse attemptSendOtpWithRetry(String mobile, int retryCount) {
+		int attempts = 0;
+		OtpSendResponse resp = null;
+		while (attempts <= retryCount) {
+			attempts++;
+			try {
+				LOGGER.info("Attempt #{} to send OTP to {}", attempts, mobile);
+				resp = otpClient.sendOtp(mobile);
+				if (resp != null && resp.isSuccess()) {
+					LOGGER.info("OTP send succeeded on attempt #{} for {}", attempts, mobile);
+					return resp;
+				}
+				// If response is non-null but indicates failure, we still may not want to retry for logical errors
+				if (resp != null && !resp.isSuccess()) {
+					LOGGER.warn("OTP service responded with failure on attempt #{} for {}: {}", attempts, mobile, resp.getMessage());
+					// Do not retry for application-level failures (invalid number etc.)
+					return resp;
+				}
+			} catch (Exception ex) {
+				LOGGER.error("Exception while sending OTP on attempt #{} for {}: {}", attempts, mobile, ex.getMessage(), ex);
+				// continue to retry if attempts remain
+			}
+			// loop continues to retry if attempts <= retryCount
+		}
+
+		// After retries, if resp is null (no response received), treat as unrecoverable and let global handler handle it via exception
+		LOGGER.error("OTP service returned null after {} attempts for {}", attempts - 1, mobile);
+		throw new CustomException("OTP send service returned null", "FAILED", 500, "OtpClient returned null after retries");
+	}
+
 	@Override
 	@Transactional
 	public ResponseModel<?> registerUser(RegisterRequest request) {
@@ -188,7 +219,7 @@ public class AuthServiceImpl implements AuthService {
 //				
 //				if (user != null) {
 //					userDetailsDTO = UserDetailsDTO.builder().id(user.getId()).userEmailId(user.getUserEmailId())
-//							.userMobNo(user.getUserMobNo()).userName(user.getUserName()).build();
+//						.userMobNo(user.getUserMobNo()).userName(user.getUserName()).build();
 //				}
 //				AuthResponses authResp = new AuthResponses(token, "Success", "Login Done", 200, userDetailsDTO);
 //				return ResponseModel.builder().message("Login Done").status("Success").statusCode(200).data(authResp)