From d76af8c2aa54061c77ccc450dec86c5355612218 Mon Sep 17 00:00:00 2001
From: Artem Bilan <abilan@pivotal.io>
Date: Wed, 1 Nov 2017 12:44:47 -0400
Subject: [PATCH] Fix HTTP module for proper RFC date formats

* Copy data format algorithm from the Spring Web `HttpHeaders` into the
`DefaultHttpHeaderMapper`
* Fix `HttpProxyScenarioTests` for proper zoned date formatting
---
 .../http/support/DefaultHttpHeaderMapper.java | 20 ++++++++++++-------
 .../http/HttpProxyScenarioTests.java          | 20 +++++++++++--------
 2 files changed, 25 insertions(+), 15 deletions(-)

diff --git a/spring-integration-http/src/main/java/org/springframework/integration/http/support/DefaultHttpHeaderMapper.java b/spring-integration-http/src/main/java/org/springframework/integration/http/support/DefaultHttpHeaderMapper.java
index afd0c16658..d7a0f4b009 100644
--- a/spring-integration-http/src/main/java/org/springframework/integration/http/support/DefaultHttpHeaderMapper.java
+++ b/spring-integration-http/src/main/java/org/springframework/integration/http/support/DefaultHttpHeaderMapper.java
@@ -257,11 +257,14 @@ public class DefaultHttpHeaderMapper implements HeaderMapper<HttpHeaders>, BeanF
 
 	public static final String HTTP_RESPONSE_HEADER_NAME_PATTERN = "HTTP_RESPONSE_HEADERS";
 
+	// Copy of 'org.springframework.http.HttpHeaders#GMT'
+	private static final ZoneId GMT = ZoneId.of("GMT");
+
 	// Copy of 'org.springframework.http.HttpHeaders#DATE_FORMATS'
 	protected static final DateTimeFormatter[] DATE_FORMATS = new DateTimeFormatter[] {
-			DateTimeFormatter.ofPattern("EEE, dd MMM yyyy HH:mm:ss zzz", Locale.US).withZone(ZoneId.of("GMT")),
-			DateTimeFormatter.ofPattern("EEE, dd-MMM-yy HH:mm:ss zzz", Locale.US).withZone(ZoneId.of("GMT")),
-			DateTimeFormatter.ofPattern("EEE MMM dd HH:mm:ss yyyy", Locale.US).withZone(ZoneId.of("GMT"))
+			DateTimeFormatter.RFC_1123_DATE_TIME,
+			DateTimeFormatter.ofPattern("EEEE, dd-MMM-yy HH:mm:ss zz", Locale.US),
+			DateTimeFormatter.ofPattern("EEE MMM dd HH:mm:ss yyyy", Locale.US).withZone(GMT)
 	};
 
 	static {
@@ -1069,22 +1072,25 @@ public class DefaultHttpHeaderMapper implements HeaderMapper<HttpHeaders>, BeanF
 	// Utility methods
 
 	protected long getFirstDate(String headerValue, String headerName) {
-		for (DateTimeFormatter dateFormat : DATE_FORMATS) {
+		for (DateTimeFormatter dateFormatter : DATE_FORMATS) {
 			try {
-				return dateFormat.parse(headerValue, ZonedDateTime::from)
+				return ZonedDateTime.parse(headerValue, dateFormatter)
 						.toInstant()
 						.toEpochMilli();
 			}
-			catch (DateTimeParseException e) {
+			catch (DateTimeParseException ex) {
 				// ignore
 			}
 		}
+
 		throw new IllegalArgumentException("Cannot parse date value '" + headerValue + "' for '" + headerName
 				+ "' header");
 	}
 
 	protected String formatDate(long date) {
-		return DATE_FORMATS[0].format(Instant.ofEpochMilli(date));
+		Instant instant = Instant.ofEpochMilli(date);
+		ZonedDateTime zonedDateTime = ZonedDateTime.ofInstant(instant, GMT);
+		return DATE_FORMATS[0].format(zonedDateTime);
 	}
 
 	/**
diff --git a/spring-integration-http/src/test/java/org/springframework/integration/http/HttpProxyScenarioTests.java b/spring-integration-http/src/test/java/org/springframework/integration/http/HttpProxyScenarioTests.java
index 8d6afa320f..03a7a3e3ac 100644
--- a/spring-integration-http/src/test/java/org/springframework/integration/http/HttpProxyScenarioTests.java
+++ b/spring-integration-http/src/test/java/org/springframework/integration/http/HttpProxyScenarioTests.java
@@ -23,11 +23,11 @@ import static org.junit.Assert.assertThat;
 import static org.mockito.ArgumentMatchers.isNull;
 
 import java.net.URI;
-import java.text.DateFormat;
-import java.text.SimpleDateFormat;
+import java.time.Instant;
+import java.time.ZoneId;
+import java.time.ZonedDateTime;
+import java.time.format.DateTimeFormatter;
 import java.util.Calendar;
-import java.util.Locale;
-import java.util.TimeZone;
 
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -89,18 +89,22 @@ public class HttpProxyScenarioTests {
 
 	@Test
 	public void testHttpProxyScenario() throws Exception {
-		DateFormat dateFormat = new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss zzz", Locale.US);
-		dateFormat.setTimeZone(TimeZone.getTimeZone("GMT"));
+		DateTimeFormatter dateTimeFormatter = DateTimeFormatter.RFC_1123_DATE_TIME;
+		ZoneId GMT = ZoneId.of("GMT");
 
 		Calendar c = Calendar.getInstance();
 		c.set(Calendar.MILLISECOND, 0);
 
 		final long ifModifiedSince = c.getTimeInMillis();
-		String ifModifiedSinceValue = dateFormat.format(ifModifiedSince);
+		Instant instant = Instant.ofEpochMilli(ifModifiedSince);
+		ZonedDateTime zonedDateTime = ZonedDateTime.ofInstant(instant, GMT);
+		String ifModifiedSinceValue = dateTimeFormatter.format(zonedDateTime);
 
 		c.add(Calendar.DATE, -1);
 		long ifUnmodifiedSince = c.getTimeInMillis();
-		final String ifUnmodifiedSinceValue = dateFormat.format(ifUnmodifiedSince);
+		instant = Instant.ofEpochMilli(ifUnmodifiedSince);
+		zonedDateTime = ZonedDateTime.ofInstant(instant, GMT);
+		final String ifUnmodifiedSinceValue = dateTimeFormatter.format(zonedDateTime);
 
 		MockHttpServletRequest request = new MockHttpServletRequest("GET", "/test");
 		request.setQueryString("foo=bar&FOO=BAR");