From 21719bb0417c9347a12036c0072a73646d396bd3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christian=20B=C3=BChler?= <christian.buehler@flightright.de>
Date: Wed, 3 Jan 2018 14:24:49 +0100
Subject: [PATCH] #686 - Support whitespace in Links header (RFC 5988).

RFC 5988 (https://tools.ietf.org/html/rfc5988#section-5.5) has clear examples of whitespace in link headers. This commit introduces support (and tests) to support these spec cases.
---
 .travis.yml                                              | 2 --
 pom.xml                                                  | 1 +
 src/main/java/org/springframework/hateoas/Links.java     | 2 +-
 .../java/org/springframework/hateoas/LinksUnitTest.java  | 9 +++++++++
 4 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index 0e0047ab..8465b006 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,8 +4,6 @@ jdk:
 env:
   matrix:
     - PROFILE=non-existant
-    - PROFILE=spring43-next
-    - PROFILE=spring5
     - PROFILE=spring5-next
 addons:
   apt:
diff --git a/pom.xml b/pom.xml
index 360495f1..3711d60a 100644
--- a/pom.xml
+++ b/pom.xml
@@ -88,6 +88,7 @@
 			<id>spring5-next</id>
 			<properties>
 				<spring.version>5.0.2.BUILD-SNAPSHOT</spring.version>
+				<jackson.version>2.9.2</jackson.version>
 			</properties>
 			<repositories>
 				<repository>
diff --git a/src/main/java/org/springframework/hateoas/Links.java b/src/main/java/org/springframework/hateoas/Links.java
index 8ba46929..a8afb751 100644
--- a/src/main/java/org/springframework/hateoas/Links.java
+++ b/src/main/java/org/springframework/hateoas/Links.java
@@ -35,7 +35,7 @@ import org.springframework.util.StringUtils;
  */
 public class Links implements Iterable<Link> {
 
-	private static final Pattern LINK_HEADER_PATTERN = Pattern.compile("(<[^>]*>(;\\w+=\"[^\"]*\")+)");
+	private static final Pattern LINK_HEADER_PATTERN = Pattern.compile("(<[^>]*>(;\\s*\\w+=\"[^\"]*\")+)");
 
 	static final Links NO_LINKS = new Links(Collections.emptyList());
 
diff --git a/src/test/java/org/springframework/hateoas/LinksUnitTest.java b/src/test/java/org/springframework/hateoas/LinksUnitTest.java
index 813a4965..78c30bc2 100755
--- a/src/test/java/org/springframework/hateoas/LinksUnitTest.java
+++ b/src/test/java/org/springframework/hateoas/LinksUnitTest.java
@@ -34,6 +34,7 @@ public class LinksUnitTest {
 	static final String FIRST = "</something>;rel=\"foo\"";
 	static final String SECOND = "</somethingElse>;rel=\"bar\"";
 	static final String WITH_COMMA = "<http://localhost:8080/test?page=0&filter=foo,bar>;rel=\"foo\"";
+	static final String WITH_WHITESPACE = "</something>; rel=\"foo\"," + SECOND;
 
 	static final String LINKS = StringUtils.collectionToCommaDelimitedString(Arrays.asList(FIRST, SECOND));
 
@@ -93,4 +94,12 @@ public class LinksUnitTest {
 		assertThat(twoWithCommaInFirst.getLink("foo")).hasValue(withComma);
 		assertThat(twoWithCommaInFirst.getLink("bar")).hasValue(new Link("/somethingElse", "bar"));
 	}
+
+	/**
+	 * @see https://tools.ietf.org/html/rfc5988#section-5.5
+	 */
+	@Test
+	public void parsesLinksWithWhitespace() {
+		assertThat(Links.valueOf(WITH_WHITESPACE)).isEqualTo(reference);
+	}
 }