edited retry after calculation, check for requestid is not empty

Author: Nakul Sabharwal

src/main/java/com/microsoft/graph/content/MSBatchRequestStep.java

@@ -12,6 +12,8 @@ public class MSBatchRequestStep {
 	public MSBatchRequestStep(String requestId, Request request, List<String> arrayOfDependsOnIds) {
 		if(requestId == null)
 			throw new IllegalArgumentException("Request Id cannot be null.");
+		if(requestId.length() == 0)
+			throw new IllegalArgumentException("Request Id cannot be empty.");
 		if(request == null)
 			new IllegalArgumentException("Request cannot be null.");
 

src/main/java/com/microsoft/graph/httpcore/RetryHandler.java

@@ -81,17 +81,24 @@ && checkStatus(statusCode) && isBuffered(response, request)
 		return shouldRetry;
 	}
 
+	/**
+	 * Get retry after in milliseconds
+	 * @param response Response
+	 * @param delay Delay in seconds
+	 * @param executionCount Execution count of retries
+	 * @return Retry interval in milliseconds
+	 */
 	long getRetryAfter(Response response, long delay, int executionCount) {
 		String retryAfterHeader = response.header(RETRY_AFTER);
-		long retryDelay = RetryOptions.DEFAULT_DELAY;
+		double retryDelay = RetryOptions.DEFAULT_DELAY * DELAY_MILLISECONDS;
 		if(retryAfterHeader != null) {
-			retryDelay = Long.parseLong(retryAfterHeader);
+			retryDelay = Long.parseLong(retryAfterHeader) * DELAY_MILLISECONDS;
 		} else {
-			retryDelay = (long)((Math.pow(2.0, (double)executionCount)-1)*0.5);
-			retryDelay = executionCount < 2 ? retryDelay : retryDelay + delay + (long)Math.random(); 
+			retryDelay = (double)((Math.pow(2.0, (double)executionCount)-1)*0.5);
+			retryDelay = (executionCount < 2 ? delay : retryDelay + delay) + (double)Math.random();
 			retryDelay *= DELAY_MILLISECONDS;
 		}
-		return Math.min(retryDelay, RetryOptions.MAX_DELAY);
+		return (long)Math.min(retryDelay, RetryOptions.MAX_DELAY * DELAY_MILLISECONDS);
 	}
 
 	boolean checkStatus(int statusCode) {

src/test/java/com/microsoft/graph/httpcore/RetryHandlerTest.java

@@ -122,4 +122,37 @@ public void testRetryRequestWithExponentialBackOff() {
 
 		assertTrue(retryhandler.retryRequest(response, 1, httppost, new RetryOptions()));
 	}
+	
+	@Test
+	public void testGetRetryAfterWithHeader() {
+		RetryHandler retryHandler = new RetryHandler();
+		long delay = retryHandler.getRetryAfter(TestResponse().newBuilder().addHeader("Retry-After", "60").build(), 1, 1);
+		assertTrue(delay == 60000);
+		delay = retryHandler.getRetryAfter(TestResponse().newBuilder().addHeader("Retry-After", "1").build(), 2, 3);
+		assertTrue(delay == 1000);
+	}
+	
+	@Test
+	public void testGetRetryAfterOnFirstExecution() {
+		RetryHandler retryHandler = new RetryHandler();
+		long delay = retryHandler.getRetryAfter(TestResponse(), 3, 1);
+		assertTrue(delay > 3000);
+		delay = retryHandler.getRetryAfter(TestResponse(), 3, 2);
+		assertTrue(delay > 3100);
+	}
+	
+	@Test
+	public void testGetRetryAfterMaxExceed() {
+		RetryHandler retryHandler = new RetryHandler();
+		long delay = retryHandler.getRetryAfter(TestResponse(), 190, 1);
+		assertTrue(delay == 180000);
+	}
+	
+	Response TestResponse() {
+		return new Response.Builder()
+				.code(429)
+				.message("message")
+				.request(new Request.Builder().url("https://localhost").build())
+				.protocol(Protocol.HTTP_1_0).build();
+	}
 }