Fix HalLinkExtractor's extraction of link hrefs

Closes gh-220

Author: wilkinsona

spring-restdocs-core/src/main/java/org/springframework/restdocs/hypermedia/HalLinkExtractor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2015 the original author or authors.
+ * Copyright 2014-2016 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -54,9 +54,9 @@ private static List<Link> convertToLinks(Object object, String rel) {
 List<Link> links = new ArrayList<>();
 if (object instanceof Collection) {
 @SuppressWarnings("unchecked")
-Collection<Object> hrefObjects = (Collection<Object>) object;
-for (Object hrefObject : hrefObjects) {
-maybeAddLink(maybeCreateLink(rel, hrefObject), links);
+Collection<Object> possibleLinkObjects = (Collection<Object>) object;
+for (Object possibleLinkObject : possibleLinkObjects) {
+maybeAddLink(maybeCreateLink(rel, possibleLinkObject), links);
 }
 }
 else {
@@ -65,9 +65,12 @@ private static List<Link> convertToLinks(Object object, String rel) {
 return links;
 }
 
-private static Link maybeCreateLink(String rel, Object possibleHref) {
-if (possibleHref instanceof String) {
-return new Link(rel, (String) possibleHref);
+private static Link maybeCreateLink(String rel, Object possibleLinkObject) {
+if (possibleLinkObject instanceof Map) {
+Object hrefObject = ((Map<?, ?>) possibleLinkObject).get("href");
+if (hrefObject instanceof String) {
+return new Link(rel, (String) hrefObject);
+}
 }
 return null;
 }

spring-restdocs-core/src/test/java/org/springframework/restdocs/hypermedia/LinkExtractorsPayloadTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2015 the original author or authors.
+ * Copyright 2014-2016 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -53,7 +53,7 @@ public class LinkExtractorsPayloadTests {
 
 private final String linkType;
 
-@Parameters
+@Parameters(name = "{1}")
 public static Collection<Object[]> data() {
 return Arrays.asList(new Object[] { new HalLinkExtractor(), "hal" },
 new Object[] { new AtomLinkExtractor(), "atom" });

spring-restdocs-core/src/test/resources/link-payloads/atom/wrong-format.json

@@ -1,5 +1,9 @@
 {
-"_links": {
-"alpha": ["http://alpha.example.com/one", "http://alpha.example.com/two"]
+"links": {
+"alpha": [{
+ "href": "http://alpha.example.com/one"
+}, {
+ "href": "http://alpha.example.com/two"
+}]
 }
 }

spring-restdocs-core/src/test/resources/link-payloads/hal/multiple-links-different-rels.json

@@ -1,6 +1,10 @@
 {
 "_links": {
-"alpha": "http://alpha.example.com",
-"bravo": "http://bravo.example.com"
+"alpha": {
+"href": "http://alpha.example.com"
+},
+"bravo": {
+"href": "http://bravo.example.com"
+}
 }
 }

spring-restdocs-core/src/test/resources/link-payloads/hal/multiple-links-same-rels.json

@@ -1,5 +1,9 @@
 {
 "_links": {
-"alpha": ["http://alpha.example.com/one", "http://alpha.example.com/two"]
+"alpha": [{
+ "href": "http://alpha.example.com/one"
+}, {
+ "href": "http://alpha.example.com/two"
+}]
 }
 }

spring-restdocs-core/src/test/resources/link-payloads/hal/single-link.json

@@ -1,5 +1,7 @@
 {
 "_links": {
-"alpha": "http://alpha.example.com"
+"alpha": {
+ "href": "http://alpha.example.com"
+}
 }
 }