Add documentation for configuring a StoreResolver

#201

spring-content-rest/src/main/asciidoc/rest-index.adoc

@@ -38,15 +38,4 @@ include::rest-cors.adoc[leveloffset=+1]
 include::rest-baseuri.adoc[leveloffset=+1]
 include::rest-linkrel.adoc[leveloffset=+1]
 include::rest-fullyqualifiedlinks.adoc[leveloffset=+1]
-//[[appendix]]
-//= Appendix
-
-//:numbered!:
-// :leveloffset: +1
-// include::{spring-data-commons-docs}/repository-namespace-reference.adoc[]
-// include::{spring-data-commons-docs}/repository-populator-namespace-reference.adoc[]
-// include::{spring-data-commons-docs}/repository-query-keywords-reference.adoc[]
-// include::{spring-data-commons-docs}/repository-query-return-types-reference.adoc[]
-// include::faq.adoc[]
-// include::glossary.adoc[]
-// :leveloffset: -1
+include::rest-storeresolver.adoc[leveloffset=+1]

spring-content-rest/src/main/asciidoc/rest-storeresolver.adoc

@@ -0,0 +1,33 @@
+== Store Resolver
+Every REST request must map to one store and one store only.  However, it is entirely possible to define an application
+with multiple stores that make this impossible.
+
+For these situations you need to provide a `StoreResolver` that, based on runtime context, can resolve these conflicts.
+
+.Configuring a StoreResolver
+====
+[source, java]
+----
+@Configuration
+@EnableS3Stores
+public static class ApplicationConfig {
+
+    @Bean
+    public ContentRestConfigurer contentRestConfigurer() {
+        return new ContentRestConfigurer() {
+            @Override
+            public void configure(RestConfiguration config) {
+                config.addStoreResolver("examples", new StoreResolver() {           <1>
+                    @Override
+                    public StoreInfo resolve(StoreInfo... stores) {
+                        /* your resolver implementation */
+                    }
+                });
+            }
+        };
+    }
+}
+----
+<1> This store resolver resolves conflicts for stores exported through the path "examples"
+====
+

spring-content-rest/src/test/java/internal/org/springframework/content/rest/storeresolver/Application.java

@@ -115,8 +115,8 @@ public FileSystemResourceLoader fileSystemResourceLoader() throws IOException {
            return new FileSystemResourceLoader(Files.createTempDirectory("").toFile().getAbsolutePath());
        }
 
-		@Bean
-		public ContentRestConfigurer contentRestConfigurer() {
+       @Bean
+       public ContentRestConfigurer contentRestConfigurer() {
            return new ContentRestConfigurer() {
                @Override
                public void configure(RestConfiguration config) {

spring-content-rest/src/test/java/internal/org/springframework/content/rest/storeresolver/StoreResolverRestConfigurationIT.java

@@ -53,7 +53,7 @@ public class StoreResolverRestConfigurationIT {
                     tEntity = new Application.TEntity();
                     tEntity = repo.save(tEntity);
                 });
-                It("should return the content with 200 OK", () -> {
+                It("should return the content from the correct store", () -> {
 
                     assertThat(jpaStore, is(not(nullValue())));
                     assertThat(fsStore, is(not(nullValue())));