Allow configuration of external access url (#2385)

#### What type of PR is this?

/kind feature
/area core
/milestone 2.0

#### What this PR does / why we need it:

Many permanent links will be generated in the system, in order to ensure accessiblity, we will allow users to configure external access links instead of internal url.

#### Special notes for your reviewer:

Before starting the application, we need to modify the following configuration into the configuration file(application.yaml):

```yaml
halo:
  external-url: https://halo.run
```

Then, after booting the application, check for permalinks of attachments.

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

```release-note
支持在配置文件中修改博客访问链接
```

src/main/java/run/halo/app/config/ExtensionConfiguration.java

@@ -46,6 +46,7 @@ import run.halo.app.extension.controller.Controller;
 import run.halo.app.extension.controller.ControllerBuilder;
 import run.halo.app.extension.controller.ControllerManager;
 import run.halo.app.extension.router.ExtensionCompositeRouterFunction;
+import run.halo.app.infra.ExternalUrlSupplier;
 import run.halo.app.infra.properties.HaloProperties;
 import run.halo.app.plugin.HaloPluginManager;
 import run.halo.app.plugin.resources.JsBundleRuleProvider;
@@ -173,9 +174,10 @@ public class ExtensionConfiguration {
         }
 
         @Bean
-        Controller attachmentController(ExtensionClient client, PluginManager pluginManager) {
+        Controller attachmentController(ExtensionClient client, PluginManager pluginManager,
+            ExternalUrlSupplier externalUrl) {
             return new ControllerBuilder("attachment-controller", client)
-                .reconciler(new AttachmentReconciler(client, pluginManager))
+                .reconciler(new AttachmentReconciler(client, pluginManager, externalUrl))
                 .extension(new Attachment())
                 .build();
         }

src/main/java/run/halo/app/core/extension/attachment/endpoint/AttachmentEndpoint.java

@@ -5,14 +5,12 @@ import static org.springdoc.core.fn.builders.content.Builder.contentBuilder;
 import static org.springdoc.core.fn.builders.schema.Builder.schemaBuilder;
 import static org.springframework.web.reactive.function.BodyExtractors.toMultipartData;
 import static org.springframework.web.reactive.function.server.RequestPredicates.contentType;
-import static run.halo.app.core.extension.attachment.Constant.FINALIZER_NAME;
 import static run.halo.app.extension.ListResult.generateGenericClass;
 import static run.halo.app.extension.router.QueryParamBuildUtil.buildParametersFromType;
 import static run.halo.app.extension.router.selector.SelectorUtil.labelAndFieldSelectorToPredicate;
 
 import io.swagger.v3.oas.annotations.media.Schema;
 import java.util.Optional;
-import java.util.Set;
 import java.util.function.Predicate;
 import lombok.extern.slf4j.Slf4j;
 import org.pf4j.PluginManager;
@@ -125,8 +123,6 @@ public class AttachmentEndpoint implements CustomEndpoint {
                                     // validate the group name
                                     spec.setGroupRef(Ref.of(groupName));
                                 }
-                                // set finalizers mandatory
-                                attachment.getMetadata().setFinalizers(Set.of(FINALIZER_NAME));
                             }))
                         .next()
                         .switchIfEmpty(Mono.error(

src/main/java/run/halo/app/core/extension/reconciler/attachment/AttachmentReconciler.java

@@ -1,9 +1,9 @@
 package run.halo.app.core.extension.reconciler.attachment;
 
-import java.nio.charset.StandardCharsets;
+import java.util.HashSet;
+import java.util.Set;
 import lombok.extern.slf4j.Slf4j;
 import org.pf4j.PluginManager;
-import org.springframework.web.util.UriUtils;
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
 import run.halo.app.core.extension.attachment.Attachment;
@@ -16,6 +16,7 @@ import run.halo.app.extension.ConfigMap;
 import run.halo.app.extension.ExtensionClient;
 import run.halo.app.extension.controller.Reconciler;
 import run.halo.app.extension.controller.Reconciler.Request;
+import run.halo.app.infra.ExternalUrlSupplier;
 import run.halo.app.infra.exception.NotFoundException;
 
 @Slf4j
@@ -25,9 +26,13 @@ public class AttachmentReconciler implements Reconciler<Request> {
 
     private final PluginManager pluginManager;
 
-    public AttachmentReconciler(ExtensionClient client, PluginManager pluginManager) {
+    private final ExternalUrlSupplier externalUrl;
+
+    public AttachmentReconciler(ExtensionClient client, PluginManager pluginManager,
+        ExternalUrlSupplier externalUrl) {
         this.client = client;
         this.pluginManager = pluginManager;
+        this.externalUrl = externalUrl;
     }
 
     @Override
@@ -43,22 +48,25 @@ public class AttachmentReconciler implements Reconciler<Request> {
                         .orElseThrow();
                 var deleteOption = new DeleteOption(attachment, policy, configMap);
                 Flux.fromIterable(pluginManager.getExtensions(AttachmentHandler.class))
-                    .concatMap(handler -> handler.delete(deleteOption))
+                    .concatMap(handler -> handler.delete(deleteOption)).next().switchIfEmpty(
-                    .next()
+                        Mono.error(() -> new NotFoundException(
-                    .switchIfEmpty(Mono.error(() -> new NotFoundException(
+                            "No suitable handler found to delete the attachment")))
-                        "No suitable handler found to delete the attachment")))
+                    .doOnNext(deleted -> removeFinalizer(deleted.getMetadata().getName())).block();
-                    .doOnNext(deleted -> removeFinalizer(deleted.getMetadata().getName()))
-                    .block();
                 return;
             }
+            // add finalizer
+            addFinalizerIfNotSet(request.name(), attachment.getMetadata().getFinalizers());
+
             var annotations = attachment.getMetadata().getAnnotations();
             if (annotations != null) {
                 String permalink = null;
                 var localRelativePath = annotations.get(Constant.LOCAL_REL_PATH_ANNO_KEY);
                 if (localRelativePath != null) {
                     // TODO Add router function here.
-                    permalink = "http://localhost:8090/upload/" + localRelativePath;
+                    permalink = externalUrl.get()
-                    permalink = UriUtils.encodePath(permalink, StandardCharsets.UTF_8);
+                        .resolve("/upload/" + localRelativePath)
+                        .normalize()
+                        .toASCIIString();
                 } else {
                     var externalLink = annotations.get(Constant.EXTERNAL_LINK_ANNO_KEY);
                     if (externalLink != null) {
@@ -85,14 +93,29 @@ public class AttachmentReconciler implements Reconciler<Request> {
     }
 
     void removeFinalizer(String attachmentName) {
-        client.fetch(Attachment.class, attachmentName)
+        client.fetch(Attachment.class, attachmentName).ifPresent(attachment -> {
-            .ifPresent(attachment -> {
+            var finalizers = attachment.getMetadata().getFinalizers();
-                var finalizers = attachment.getMetadata().getFinalizers();
+            if (finalizers != null && finalizers.remove(Constant.FINALIZER_NAME)) {
-                if (finalizers != null && finalizers.remove(Constant.FINALIZER_NAME)) {
+                // update it
-                    // update it
+                client.update(attachment);
-                    client.update(attachment);
+            }
-                }
+        });
-            });
+    }
+
+    void addFinalizerIfNotSet(String attachmentName, Set<String> existingFinalizers) {
+        if (existingFinalizers != null && existingFinalizers.contains(Constant.FINALIZER_NAME)) {
+            return;
+        }
+
+        client.fetch(Attachment.class, attachmentName).ifPresent(attachment -> {
+            var finalizers = attachment.getMetadata().getFinalizers();
+            if (finalizers == null) {
+                finalizers = new HashSet<>();
+                attachment.getMetadata().setFinalizers(finalizers);
+            }
+            finalizers.add(Constant.FINALIZER_NAME);
+            client.update(attachment);
+        });
     }
 
 }

src/main/java/run/halo/app/infra/ExternalUrlSupplier.java

@@ -0,0 +1,13 @@
+package run.halo.app.infra;
+
+import java.net.URI;
+import java.util.function.Supplier;
+
+/**
+ * Represents a supplier of external url configuration.
+ *
+ * @author johnniang
+ */
+public interface ExternalUrlSupplier extends Supplier<URI> {
+
+}

src/main/java/run/halo/app/infra/HaloPropertiesExternalUrlSupplier.java

@@ -0,0 +1,25 @@
+package run.halo.app.infra;
+
+import java.net.URI;
+import org.springframework.stereotype.Component;
+import run.halo.app.infra.properties.HaloProperties;
+
+/**
+ * Default implementation for getting external url from halo properties.
+ *
+ * @author johnniang
+ */
+@Component
+public class HaloPropertiesExternalUrlSupplier implements ExternalUrlSupplier {
+
+    private final HaloProperties haloProperties;
+
+    public HaloPropertiesExternalUrlSupplier(HaloProperties haloProperties) {
+        this.haloProperties = haloProperties;
+    }
+
+    @Override
+    public URI get() {
+        return haloProperties.getExternalUrl();
+    }
+}

src/main/java/run/halo/app/infra/properties/HaloProperties.java

@@ -1,10 +1,14 @@
 package run.halo.app.infra.properties;
 
+import jakarta.validation.Valid;
+import jakarta.validation.constraints.NotNull;
+import java.net.URI;
 import java.nio.file.Path;
 import java.util.HashSet;
 import java.util.Set;
 import lombok.Data;
 import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.validation.annotation.Validated;
 
 /**
  * @author guqing
@@ -12,10 +16,15 @@ import org.springframework.boot.context.properties.ConfigurationProperties;
  */
 @Data
 @ConfigurationProperties(prefix = "halo")
+@Validated
 public class HaloProperties {
 
+    @NotNull
     private Path workDir;
 
+    @NotNull
+    private URI externalUrl;
+
     private Set<String> initialExtensionLocations = new HashSet<>();
 
     /**
@@ -25,7 +34,9 @@ public class HaloProperties {
      */
     private boolean requiredExtensionDisabled;
 
+    @Valid
     private final ExtensionProperties extension = new ExtensionProperties();
 
+    @Valid
     private final SecurityProperties security = new SecurityProperties();
 }

src/main/resources/application.yaml

@@ -14,6 +14,7 @@ spring:
       platform: h2
 
 halo:
+  external-url: "http://${server.address:localhost}:${server.port}"
   security:
     oauth2:
       jwt:

src/test/java/run/halo/app/PathPrefixPredicateTest.java

@@ -2,13 +2,10 @@ package run.halo.app;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
-import java.util.List;
 import org.junit.jupiter.api.Test;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.method.HandlerTypePredicate;
-import reactor.core.publisher.Flux;
-import reactor.core.publisher.Mono;
 
 /**
  * Test case for api path prefix predicate.
@@ -37,14 +34,4 @@ public class PathPrefixPredicateTest {
 
     }
 
-    @Test
-    void test() {
-        Flux.fromIterable(List.of(1, 2, 3))
-            .flatMap(i -> {
-                if (i == 2) {
-                    return Mono.empty();
-                }
-                return Mono.just(i);
-            }).subscribe(System.out::println);
-    }
 }

src/test/java/run/halo/app/infra/HaloPropertiesExternalUrlSupplierTest.java

@@ -0,0 +1,29 @@
+package run.halo.app.infra;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.net.URI;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.Mockito;
+import org.mockito.junit.jupiter.MockitoExtension;
+import run.halo.app.infra.properties.HaloProperties;
+
+@ExtendWith(MockitoExtension.class)
+class HaloPropertiesExternalUrlSupplierTest {
+
+    @Mock
+    HaloProperties haloProperties;
+
+    @InjectMocks
+    HaloPropertiesExternalUrlSupplier externalUrl;
+
+    @Test
+    void get() {
+        URI fakeUri = URI.create("fake-url");
+        Mockito.when(haloProperties.getExternalUrl()).thenReturn(fakeUri);
+        assertEquals(fakeUri, externalUrl.get());
+    }
+}

src/test/resources/application.yaml

@@ -14,6 +14,7 @@ spring:
 
 halo:
   work-dir: ${user.home}/halo-next-test
+  external-url: "http://${server.address:localhost}:${server.port}"
   security:
     initializer:
       disabled: true