Merge pull request #98 from xenit-eu/curie-provider

Add custom CurieProvider

contentgrid-spring-boot-autoconfigure/src/main/java/com/contentgrid/spring/boot/autoconfigure/data/web/ContentGridSpringDataRestAutoConfiguration.java

@@ -1,8 +1,11 @@
 package com.contentgrid.spring.boot.autoconfigure.data.web;
 
 import com.contentgrid.spring.data.rest.affordances.ContentGridSpringDataRestAffordancesConfiguration;
+import com.contentgrid.spring.data.rest.hal.ContentGridCurieConfiguration;
+import com.contentgrid.spring.data.rest.hal.CurieProviderCustomizer;
 import com.contentgrid.spring.data.rest.webmvc.ContentGridSpringDataRestProfileConfiguration;
 import org.springframework.boot.autoconfigure.AutoConfigureAfter;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.hateoas.HypermediaAutoConfiguration;
 import org.springframework.boot.context.properties.ConfigurationProperties;
@@ -15,8 +18,11 @@
 
 @Configuration
 @ConditionalOnClass({ContentGridSpringDataRestConfiguration.class, RepositoryRestMvcConfiguration.class})
-@Import({ContentGridSpringDataRestConfiguration.class, ContentGridSpringDataRestProfileConfiguration.class,
-        ContentGridSpringDataRestAffordancesConfiguration.class})
+@Import({
+        ContentGridSpringDataRestConfiguration.class,
+        ContentGridSpringDataRestProfileConfiguration.class,
+        ContentGridSpringDataRestAffordancesConfiguration.class
+})
 @AutoConfigureAfter(HypermediaAutoConfiguration.class)
 public class ContentGridSpringDataRestAutoConfiguration {
 
@@ -26,4 +32,10 @@ ContentGridRestProperties contentGridRestProperties() {
         return new ContentGridRestProperties();
     }
 
+    @ConditionalOnBean(CurieProviderCustomizer.class)
+    @Import(ContentGridCurieConfiguration.class)
+    static class CurieAutoConfiguration {
+
+    }
+
 }

contentgrid-spring-boot-autoconfigure/src/test/java/com/contentgrid/spring/boot/autoconfigure/data/web/ContentGridSpringDataRestAutoConfigurationTest.java

@@ -2,14 +2,19 @@
 
 import static org.assertj.core.api.Assertions.assertThat;
 
+import com.contentgrid.spring.data.rest.hal.CurieProviderCustomizer;
 import org.junit.jupiter.api.Test;
 import org.springframework.boot.autoconfigure.AutoConfigurations;
 import org.springframework.boot.autoconfigure.data.rest.RepositoryRestMvcAutoConfiguration;
+import org.springframework.boot.context.annotation.UserConfigurations;
 import org.springframework.boot.test.context.FilteredClassLoader;
 import org.springframework.boot.test.context.runner.WebApplicationContextRunner;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
 import org.springframework.data.rest.webmvc.ContentGridSpringDataRestConfiguration;
 import org.springframework.data.rest.webmvc.DelegatingRepositoryPropertyReferenceController;
 import org.springframework.data.rest.webmvc.config.RepositoryRestMvcConfiguration;
+import org.springframework.hateoas.mediatype.hal.CurieProvider;
 import org.springframework.hateoas.mediatype.hal.HalConfiguration;
 import org.springframework.hateoas.mediatype.hal.forms.HalFormsConfiguration;
 
@@ -26,6 +31,7 @@ void checkContentGridSpringDataRest() {
         contextRunner.run(context -> {
             assertThat(context).hasSingleBean(DelegatingRepositoryPropertyReferenceController.class);
             assertThat(context).hasBean("repositoryPropertyReferenceController");
+            assertThat(context).doesNotHaveBean(CurieProvider.class);
             assertThat(context).hasNotFailed();
         });
     }
@@ -62,4 +68,23 @@ void when_springDataRestWebmvc_isNotOnClasspath() {
                     assertThat(context).hasNotFailed();
                 });
     }
+
+    @Test
+    void when_curieProviderCustomizer_isPresent() {
+        contextRunner
+                .withConfiguration(UserConfigurations.of(CurieCustomizerConfiguration.class))
+                .run(context -> {
+                    assertThat(context).hasSingleBean(CurieProvider.class);
+                    assertThat(context).hasNotFailed();
+                });
+    }
+
+    @Configuration(proxyBeanMethods = false)
+    private static class CurieCustomizerConfiguration {
+        @Bean
+        CurieProviderCustomizer myCurieProviderCustomizer() {
+            return CurieProviderCustomizer.register("test", "https://test.invalid/{rel}");
+        }
+
+    }
 }

contentgrid-spring-data-rest/src/main/java/com/contentgrid/spring/data/rest/hal/ContentGridCurieConfiguration.java

@@ -0,0 +1,22 @@
+package com.contentgrid.spring.data.rest.hal;
+
+import org.springframework.beans.factory.ObjectProvider;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.hateoas.mediatype.hal.CurieProvider;
+
+@Configuration(proxyBeanMethods = false)
+public class ContentGridCurieConfiguration {
+
+    @Bean
+    CurieProvider contentGridCurieProvider(ObjectProvider<CurieProviderCustomizer> customizers) {
+        CurieProviderBuilder curieProvider = new ContentGridCurieProvider();
+
+        for (CurieProviderCustomizer customizer : customizers) {
+            curieProvider = customizer.customize(curieProvider);
+        }
+
+        return curieProvider.build();
+    }
+
+}

contentgrid-spring-data-rest/src/main/java/com/contentgrid/spring/data/rest/hal/ContentGridCurieProvider.java

@@ -0,0 +1,95 @@
+package com.contentgrid.spring.data.rest.hal;
+
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
+import lombok.RequiredArgsConstructor;
+import org.springframework.hateoas.IanaLinkRelations;
+import org.springframework.hateoas.IanaUriSchemes;
+import org.springframework.hateoas.Link;
+import org.springframework.hateoas.LinkRelation;
+import org.springframework.hateoas.Links;
+import org.springframework.hateoas.UriTemplate;
+import org.springframework.hateoas.mediatype.hal.CurieProvider;
+import org.springframework.hateoas.mediatype.hal.HalLinkRelation;
+
+@RequiredArgsConstructor
+class ContentGridCurieProvider implements CurieProvider, CurieProviderBuilder {
+
+    private final Map<String, UriTemplate> curies;
+
+    public ContentGridCurieProvider() {
+        this(Map.of());
+    }
+
+    @Override
+    public HalLinkRelation getNamespacedRelFrom(Link link) {
+        return getNamespacedRelFor(link.getRel());
+    }
+
+    @Override
+    public HalLinkRelation getNamespacedRelFor(LinkRelation rel) {
+        assertRegisteredCurie(rel);
+        return HalLinkRelation.of(rel);
+    }
+
+    @Override
+    public Collection<?> getCurieInformation(Links links) {
+        return curies.entrySet().stream()
+                .map(it -> createCurieLink(it.getKey(), it.getValue()))
+                .toList();
+    }
+
+    private Link createCurieLink(String name, UriTemplate template) {
+        return Link.of(
+                template,
+                HalLinkRelation.CURIES
+        ).withName(name);
+    }
+
+    @Override
+    public CurieProviderBuilder withCurie(String prefix, UriTemplate template) {
+        if(curies.containsKey(prefix)) {
+            throw new IllegalArgumentException("CURIE prefix '%s' is already registered with template '%s' and can not be re-registered with template '%s'.".formatted(
+                    prefix,
+                    curies.get(prefix),
+                    template
+            ));
+        }
+        if(IanaUriSchemes.isIanaUriScheme(prefix)) {
+            throw new IllegalArgumentException("CURIE prefix '%s' can not be an IANA-registered URI scheme.".formatted(prefix));
+        }
+        var curies = new HashMap<>(this.curies);
+        curies.put(prefix, template);
+        return new ContentGridCurieProvider(curies);
+    }
+
+    @Override
+    public CurieProvider build() {
+        return this;
+    }
+
+    private void assertRegisteredCurie(LinkRelation rel) {
+        var relation = rel.value();
+        int firstColonIndex = relation.indexOf(':');
+
+        String curie = firstColonIndex == -1 ? null : relation.substring(0, firstColonIndex);
+
+        if(curie == null) {
+            // Not curie -> need to check if it's a registered link relation
+            if(!IanaLinkRelations.isIanaRel(relation)) {
+                throw new IllegalArgumentException("Relation '%s' is not an IANA-registered relation".formatted(relation));
+            }
+            return;
+        }
+
+        if(IanaUriSchemes.isIanaUriScheme(curie)) {
+            // Not a curie, but a RFC 5988 #4.2a extension relation type
+            return;
+        }
+
+        if(!curies.containsKey(curie)) {
+            throw new IllegalArgumentException("Relation '%s' uses CURIE that is not registered".formatted(relation));
+        }
+    }
+}

contentgrid-spring-data-rest/src/main/java/com/contentgrid/spring/data/rest/hal/CurieProviderBuilder.java

@@ -0,0 +1,24 @@
+package com.contentgrid.spring.data.rest.hal;
+
+import org.springframework.hateoas.UriTemplate;
+import org.springframework.hateoas.mediatype.hal.CurieProvider;
+
+/**
+ * Fluent builder for {@link CurieProvider}
+ */
+public interface CurieProviderBuilder {
+
+    /**
+     * Adds a mapping from CURIE prefix to a {@link UriTemplate} for resolving the CURIE against
+     * @param prefix CURIE prefix
+     * @param template Template to use to resolve the CURIE
+     * @return Copy with new curie mapping applied
+     */
+    CurieProviderBuilder withCurie(String prefix, UriTemplate template);
+
+    /**
+     * Builds a {@link CurieProvider} with the mappings specified in the builder
+     * @return An immutable {@link CurieProvider} instance
+     */
+    CurieProvider build();
+}

contentgrid-spring-data-rest/src/main/java/com/contentgrid/spring/data/rest/hal/CurieProviderCustomizer.java

@@ -0,0 +1,47 @@
+package com.contentgrid.spring.data.rest.hal;
+
+import org.springframework.hateoas.UriTemplate;
+
+/**
+ * Customizer interface for {@link CurieProviderBuilder}.
+ * <p>
+ * By implementing this interface and exposing them as beans, they will automatically be applied to the default {@link org.springframework.hateoas.mediatype.hal.CurieProvider}
+ */
+@FunctionalInterface
+public interface CurieProviderCustomizer {
+
+    /**
+     * Customize the {@link CurieProviderBuilder}
+     * @param builder current builder
+     * @return builder with the desired customizations applied
+     */
+    CurieProviderBuilder customize(CurieProviderBuilder builder);
+
+    /**
+     * Register a mapping between CURIE prefix and a URI template
+     *
+     * @param curiePrefix The CURIE prefix
+     * @param template The URI template to use
+     * @return customizer that registers a CURIE prefix mapping
+     *
+     * @see CurieProviderBuilder#withCurie(String, UriTemplate) for the builder method
+     * @see #register(String, String) for a shortcut that does not require a {@link UriTemplate} instance
+     */
+    static CurieProviderCustomizer register(String curiePrefix, UriTemplate template) {
+        return builder -> builder.withCurie(curiePrefix, template);
+    }
+
+    /**
+     * Register a mapping between CURIE prefix and a URI template
+     *
+     * @param curiePrefix The CURIE prefix
+     * @param template The URI template to use
+     * @return customizer that registers a CURIE prefix mapping
+     *
+     * @see CurieProviderBuilder#withCurie(String, UriTemplate) for the builder method
+     * @see #register(String, UriTemplate) for passing a {@link UriTemplate} directly
+     */
+    static CurieProviderCustomizer register(String curiePrefix, String template) {
+        return register(curiePrefix, UriTemplate.of(template));
+    }
+}

contentgrid-spring-data-rest/src/test/java/com/contentgrid/spring/data/rest/affordances/AffordanceInjectingSelfLinkProviderTest.java

@@ -95,7 +95,7 @@ void templatesAddedOnCollectionResource() throws Exception {
                 .andExpect(MockMvcResultMatchers.content().json("""
                         {
                             _embedded: {
-                                customers: [
+                                "d:customers": [
                                     {
                                         _links: {
                                             self: {
@@ -137,7 +137,7 @@ void templatesAddedOnCollectionResource() throws Exception {
                 // No top-level _templates are present
                 .andExpect(MockMvcResultMatchers.jsonPath("$.keys()", Matchers.not(Matchers.contains("_templates"))))
                 // The templates of the embedded object only contain a default and a delete template
-                .andExpect(MockMvcResultMatchers.jsonPath("$._embedded.customers[0]._templates.keys()", Matchers.containsInAnyOrder("default", "delete")));
+                .andExpect(MockMvcResultMatchers.jsonPath("$._embedded.['d:customers'][0]._templates.keys()", Matchers.containsInAnyOrder("default", "delete")));
         ;
     }
 

contentgrid-spring-data-rest/src/test/java/com/contentgrid/spring/data/rest/hal/ContentGridCurieConfigurationTest.java

@@ -0,0 +1,52 @@
+package com.contentgrid.spring.data.rest.hal;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import com.contentgrid.spring.data.rest.hal.ContentGridCurieConfigurationTest.CurieProviderCustomizers;
+import org.assertj.core.api.InstanceOfAssertFactories;
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.boot.test.context.TestConfiguration;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.annotation.Bean;
+import org.springframework.hateoas.Link;
+import org.springframework.hateoas.Links;
+import org.springframework.hateoas.UriTemplate;
+import org.springframework.hateoas.mediatype.hal.CurieProvider;
+import org.springframework.hateoas.mediatype.hal.HalLinkRelation;
+import org.springframework.test.context.ContextConfiguration;
+
+@SpringBootTest
+@ContextConfiguration(classes = {
+        ContentGridCurieConfiguration.class,
+        CurieProviderCustomizers.class
+})
+@AutoConfigureMockMvc(printOnlyOnFailure = false)
+class ContentGridCurieConfigurationTest {
+
+    @TestConfiguration(proxyBeanMethods = false)
+    static class CurieProviderCustomizers {
+        @Bean
+        CurieProviderCustomizer curieProviderTestCustomizer() {
+            return builder -> builder.withCurie("test", UriTemplate.of("https://example.com/rels/{x}"));
+        }
+
+        @Bean
+        CurieProviderCustomizer curieProviderExtCustomizer() {
+            return builder -> builder.withCurie("ext", UriTemplate.of("https://ext.invalid/{rel}"));
+        }
+    }
+
+    @Test
+    void customizersApplied(ApplicationContext context) {
+        var curies = context.getBean(CurieProvider.class).getCurieInformation(Links.NONE);
+
+        assertThat(curies).asInstanceOf(InstanceOfAssertFactories.list(Link.class)).containsExactlyInAnyOrder(
+                Link.of("https://example.com/rels/{x}", HalLinkRelation.CURIES).withName("test"),
+                Link.of("https://ext.invalid/{rel}", HalLinkRelation.CURIES).withName("ext")
+        );
+    }
+
+
+}