feat: support route pattern /categories/{categorySlug}/{postSlug} for post access (#7331)

#### What type of PR is this?
/kind feature
/milestone 2.20.x

#### What this PR does / why we need it:
文章访问路径支持设置 `/categories/{categorySlug}/{postSlug}` 的形式

#### Which issue(s) this PR fixes:

Fixes #7330

#### Does this PR introduce a user-facing change?

```release-note
文章访问路径支持设置 `/categories/{categorySlug}/{postSlug}` 的形式
```

application/src/main/java/run/halo/app/content/PostService.java

@@ -1,8 +1,10 @@
 package run.halo.app.content;
 
+import java.util.List;
 import org.springframework.lang.NonNull;
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
+import run.halo.app.core.extension.content.Category;
 import run.halo.app.core.extension.content.Post;
 import run.halo.app.extension.ListResult;
 
@@ -52,4 +54,6 @@ public interface PostService {
     Mono<ContentWrapper> deleteContent(String postName, String snapshotName);
 
     Mono<Post> recycleBy(String postName, String username);
+
+    Flux<Category> listCategories(List<String> categories);
 }

application/src/main/java/run/halo/app/content/impl/PostServiceImpl.java

@@ -4,9 +4,11 @@ import static run.halo.app.extension.index.query.QueryFactory.in;
 
 import java.time.Duration;
 import java.time.Instant;
+import java.util.Comparator;
 import java.util.List;
 import java.util.Objects;
 import java.util.function.Function;
+import java.util.function.ToIntFunction;
 import java.util.function.UnaryOperator;
 import lombok.extern.slf4j.Slf4j;
 import org.apache.commons.lang3.StringUtils;
@@ -161,13 +163,17 @@ public class PostServiceImpl extends AbstractContentService implements PostServi
         return client.listAll(Tag.class, listOptions, Sort.by("metadata.creationTimestamp"));
     }
 
-    private Flux<Category> listCategories(List<String> categoryNames) {
+    @Override
+    public Flux<Category> listCategories(List<String> categoryNames) {
         if (categoryNames == null) {
             return Flux.empty();
         }
+        ToIntFunction<Category> comparator =
+            category -> categoryNames.indexOf(category.getMetadata().getName());
         var listOptions = new ListOptions();
         listOptions.setFieldSelector(FieldSelector.of(in("metadata.name", categoryNames)));
-        return client.listAll(Category.class, listOptions, Sort.by("metadata.creationTimestamp"));
+        return client.listAll(Category.class, listOptions, Sort.unsorted())
+            .sort(Comparator.comparingInt(comparator));
     }
 
     private Flux<Contributor> listContributors(List<String> usernames) {

application/src/main/java/run/halo/app/content/permalinks/PostPermalinkPolicy.java

@@ -12,6 +12,7 @@ import java.util.Map;
 import java.util.Properties;
 import lombok.RequiredArgsConstructor;
 import org.springframework.stereotype.Component;
+import run.halo.app.content.PostService;
 import run.halo.app.core.extension.content.Constant;
 import run.halo.app.core.extension.content.Post;
 import run.halo.app.extension.MetadataUtil;
@@ -27,12 +28,14 @@ import run.halo.app.infra.utils.PathUtils;
 @Component
 @RequiredArgsConstructor
 public class PostPermalinkPolicy implements PermalinkPolicy<Post> {
+    public static final String DEFAULT_CATEGORY = "default";
     public static final String DEFAULT_PERMALINK_PATTERN =
         SystemSetting.ThemeRouteRules.empty().getPost();
     private static final NumberFormat NUMBER_FORMAT = new DecimalFormat("00");
 
     private final SystemConfigurableEnvironmentFetcher environmentFetcher;
     private final ExternalUrlSupplier externalUrlSupplier;
+    private final PostService postService;
 
     @Override
     public String permalink(Post post) {
@@ -62,6 +65,13 @@ public class PostPermalinkPolicy implements PermalinkPolicy<Post> {
         properties.put("month", NUMBER_FORMAT.format(zonedDateTime.getMonthValue()));
         properties.put("day", NUMBER_FORMAT.format(zonedDateTime.getDayOfMonth()));
 
+        var categorySlug = postService.listCategories(post.getSpec().getCategories())
+            .next()
+            .blockOptional()
+            .map(category -> category.getSpec().getSlug())
+            .orElse(DEFAULT_CATEGORY);
+        properties.put("categorySlug", categorySlug);
+
         String simplifiedPattern = PathUtils.simplifyPathPattern(pattern);
         String permalink =
             PROPERTY_PLACEHOLDER_HELPER.replacePlaceholders(simplifiedPattern, properties);

application/src/main/java/run/halo/app/core/reconciler/CategoryReconciler.java

@@ -8,18 +8,22 @@ import java.util.Map;
 import java.util.Set;
 import lombok.AllArgsConstructor;
 import org.springframework.context.ApplicationEventPublisher;
+import org.springframework.data.domain.Sort;
 import org.springframework.stereotype.Component;
 import org.springframework.util.CollectionUtils;
 import run.halo.app.content.CategoryService;
 import run.halo.app.content.permalinks.CategoryPermalinkPolicy;
 import run.halo.app.core.extension.content.Category;
 import run.halo.app.core.extension.content.Constant;
+import run.halo.app.core.extension.content.Post;
 import run.halo.app.event.post.CategoryHiddenStateChangeEvent;
 import run.halo.app.extension.ExtensionClient;
 import run.halo.app.extension.ExtensionUtil;
+import run.halo.app.extension.ListOptions;
 import run.halo.app.extension.controller.Controller;
 import run.halo.app.extension.controller.ControllerBuilder;
 import run.halo.app.extension.controller.Reconciler;
+import run.halo.app.extension.index.query.QueryFactory;
 
 /**
  * Reconciler for {@link Category}.
@@ -43,6 +47,7 @@ public class CategoryReconciler implements Reconciler<Reconciler.Request> {
                 if (ExtensionUtil.isDeleted(category)) {
                     if (removeFinalizers(category.getMetadata(), Set.of(FINALIZER_NAME))) {
                         refreshHiddenState(category, false);
+                        updateCategoryForPost(category.getMetadata().getName());
                         client.update(category);
                     }
                     return;
@@ -118,4 +123,18 @@ public class CategoryReconciler implements Reconciler<Reconciler.Request> {
         category.getStatusOrDefault()
             .setPermalink(categoryPermalinkPolicy.permalink(category));
     }
+
+    private void updateCategoryForPost(String categoryName) {
+        var posts = client.listAll(Post.class, ListOptions.builder()
+            .fieldQuery(QueryFactory.equal("spec.categories", categoryName))
+            .build(), Sort.by("metadata.creationTimestamp", "metadata.name")
+        );
+        for (Post post : posts) {
+            var categoryNames = post.getSpec().getCategories();
+            if (!CollectionUtils.isEmpty(categoryNames)) {
+                categoryNames.remove(categoryName);
+            }
+            client.update(post);
+        }
+    }
 }

application/src/main/java/run/halo/app/theme/router/ThemeCompositeRouterFunction.java

@@ -55,7 +55,9 @@ public class ThemeCompositeRouterFunction implements RouterFunction<ServerRespon
     @NonNull
     public Mono<HandlerFunction<ServerResponse>> route(@NonNull ServerRequest request) {
         return Flux.fromIterable(cachedRouters)
-            .concatMap(routerFunction -> routerFunction.route(request))
+            .concatMap(routerFunction -> routerFunction.route(request)
+                .filterWhen(handle -> handle.handle(request).hasElement())
+            )
             .next();
     }
 

application/src/main/java/run/halo/app/theme/router/factories/PostRouteFactory.java

@@ -4,6 +4,7 @@ import static org.apache.commons.lang3.ObjectUtils.defaultIfNull;
 import static org.apache.commons.lang3.StringUtils.isNotBlank;
 import static org.springframework.web.reactive.function.server.RequestPredicates.GET;
 import static org.springframework.web.reactive.function.server.RequestPredicates.accept;
+import static run.halo.app.content.permalinks.PostPermalinkPolicy.DEFAULT_CATEGORY;
 
 import com.google.common.cache.Cache;
 import com.google.common.cache.CacheBuilder;
@@ -33,11 +34,11 @@ import org.springframework.web.reactive.function.server.ServerResponse;
 import org.springframework.web.server.i18n.LocaleContextResolver;
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
+import run.halo.app.content.PostService;
 import run.halo.app.core.extension.content.Post;
 import run.halo.app.extension.MetadataUtil;
 import run.halo.app.extension.ReactiveExtensionClient;
 import run.halo.app.extension.index.query.QueryFactory;
-import run.halo.app.infra.exception.NotFoundException;
 import run.halo.app.infra.utils.JsonUtils;
 import run.halo.app.theme.DefaultTemplateEnum;
 import run.halo.app.theme.ViewNameResolver;
@@ -69,6 +70,7 @@ public class PostRouteFactory implements RouteFactory {
     private final TitleVisibilityIdentifyCalculator titleVisibilityIdentifyCalculator;
 
     private final LocaleContextResolver localeContextResolver;
+    private final PostService postService;
 
     @Override
     public RouterFunction<ServerResponse> create(String pattern) {
@@ -151,9 +153,27 @@ public class PostRouteFactory implements RouteFactory {
                     && matchIfPresent(variable.getMonth(), labels.get(Post.ARCHIVE_MONTH_LABEL))
                     && matchIfPresent(variable.getDay(), labels.get(Post.ARCHIVE_DAY_LABEL));
             })
+            .filterWhen(post -> {
+                if (isNotBlank(variable.getCategorySlug())) {
+                    var categoryNames = post.getSpec().getCategories();
+                    return postService.listCategories(categoryNames)
+                        .next()
+                        .filter(category -> category.getSpec().getSlug()
+                            .equals(variable.getCategorySlug())
+                        )
+                        .map(category -> category.getSpec().getSlug())
+                        .switchIfEmpty(Mono.defer(() -> {
+                            if (DEFAULT_CATEGORY.equals(variable.getCategorySlug())) {
+                                return Mono.just(DEFAULT_CATEGORY);
+                            }
+                            return Mono.empty();
+                        }))
+                        .hasElement();
+                }
+                return Mono.just(true);
+            })
             .next()
-            .flatMap(post -> postFinder.getByName(post.getMetadata().getName()))
-            .switchIfEmpty(Mono.error(new NotFoundException("Post not found")));
+            .flatMap(post -> postFinder.getByName(post.getMetadata().getName()));
     }
 
     Flux<Post> postsByPredicates(PostPatternVariable patternVariable) {
@@ -196,6 +216,7 @@ public class PostRouteFactory implements RouteFactory {
         String year;
         String month;
         String day;
+        String categorySlug;
 
         static PostPatternVariable from(ServerRequest request) {
             Map<String, String> variables = mergedVariables(request);

application/src/main/resources/extensions/system-setting.yaml

@@ -180,6 +180,8 @@ spec:
               value: '/{year:\d{4}}/{month:\d{2}}/{slug}'
             - label: '/{year}/{month}/{day}/{slug}'
               value: '/{year:\d{4}}/{month:\d{2}}/{day:\d{2}}/{slug}'
+            - label: '/categories/{categorySlug}/{slug}'
+              value: '/categories/{categorySlug}/{slug}'
           name: post
           validation: required
     - group: codeInjection

application/src/test/java/run/halo/app/content/permalinks/PostPermalinkPolicyTest.java

@@ -1,6 +1,7 @@
 package run.halo.app.content.permalinks;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.lenient;
 import static org.mockito.Mockito.when;
 
@@ -10,6 +11,7 @@ import java.text.NumberFormat;
 import java.time.Instant;
 import java.time.ZoneId;
 import java.time.ZonedDateTime;
+import java.util.List;
 import java.util.Map;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
@@ -17,9 +19,13 @@ import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.Mock;
 import org.mockito.junit.jupiter.MockitoExtension;
 import org.springframework.context.ApplicationContext;
+import reactor.core.publisher.Flux;
+import run.halo.app.content.PostService;
 import run.halo.app.content.TestPost;
+import run.halo.app.core.extension.content.Category;
 import run.halo.app.core.extension.content.Constant;
 import run.halo.app.core.extension.content.Post;
+import run.halo.app.extension.Metadata;
 import run.halo.app.extension.MetadataUtil;
 import run.halo.app.infra.ExternalUrlSupplier;
 import run.halo.app.infra.SystemConfigurableEnvironmentFetcher;
@@ -44,12 +50,17 @@ class PostPermalinkPolicyTest {
     @Mock
     private SystemConfigurableEnvironmentFetcher environmentFetcher;
 
+    @Mock
+    private PostService postService;
+
     private PostPermalinkPolicy postPermalinkPolicy;
 
     @BeforeEach
     void setUp() {
         lenient().when(externalUrlSupplier.get()).thenReturn(URI.create(""));
-        postPermalinkPolicy = new PostPermalinkPolicy(environmentFetcher, externalUrlSupplier);
+        lenient().when(postService.listCategories(any())).thenReturn(Flux.empty());
+        postPermalinkPolicy =
+            new PostPermalinkPolicy(environmentFetcher, externalUrlSupplier, postService);
     }
 
     @Test
@@ -93,6 +104,24 @@ class PostPermalinkPolicyTest {
         assertThat(permalink).isEqualTo("/posts/test-post");
     }
 
+    @Test
+    void permalinkForCategory() {
+        Post post = TestPost.postV1();
+        post.getSpec().setCategories(List.of("test-category"));
+        Map<String, String> annotations = MetadataUtil.nullSafeAnnotations(post);
+        annotations.put(Constant.PERMALINK_PATTERN_ANNO, "/{categorySlug}/{slug}");
+        post.getMetadata().setName("test-post");
+        post.getSpec().setSlug("test-post-slug");
+        Instant now = Instant.now();
+        post.getSpec().setPublishTime(now);
+
+        var category = createCategory("test-category", "test-category-slug");
+        when(postService.listCategories(post.getSpec().getCategories()))
+            .thenReturn(Flux.just(category));
+        var permalink = postPermalinkPolicy.permalink(post);
+        assertThat(permalink).isEqualTo("/test-category-slug/test-post-slug");
+    }
+
     @Test
     void permalinkWithExternalUrl() {
         Post post = TestPost.postV1();
@@ -112,4 +141,18 @@ class PostPermalinkPolicyTest {
         permalink = postPermalinkPolicy.permalink(post);
         assertThat(permalink).isEqualTo("http://example.com/2022/11/01/%E4%B8%AD%E6%96%87%20slug");
     }
+
+    private Category createCategory(String name, String slug) {
+        Category category = new Category();
+        Metadata metadata = new Metadata();
+        metadata.setName(name);
+        category.setMetadata(metadata);
+        category.setSpec(new Category.CategorySpec());
+        category.setStatus(new Category.CategoryStatus());
+
+        category.getSpec().setDisplayName("display-name");
+        category.getSpec().setSlug(slug);
+        category.getSpec().setPriority(0);
+        return category;
+    }
 }