refactor: thumbnail endpoint

application/src/main/java/run/halo/app/theme/endpoint/ThumbnailEndpoint.java

@@ -0,0 +1,168 @@
+package run.halo.app.theme.endpoint;
+
+import static io.swagger.v3.oas.annotations.media.Schema.RequiredMode.REQUIRED;
+import static org.apache.commons.lang3.StringUtils.removeStart;
+import static org.springdoc.core.fn.builders.apiresponse.Builder.responseBuilder;
+import static org.springdoc.core.fn.builders.parameter.Builder.parameterBuilder;
+
+import io.swagger.v3.oas.annotations.enums.ParameterIn;
+import io.swagger.v3.oas.annotations.media.Schema;
+import java.io.IOException;
+import java.net.URI;
+import java.time.Instant;
+import lombok.RequiredArgsConstructor;
+import org.apache.commons.lang3.StringUtils;
+import org.springdoc.core.fn.builders.operation.Builder;
+import org.springdoc.webflux.core.fn.SpringdocRouteBuilder;
+import org.springframework.boot.autoconfigure.web.WebProperties;
+import org.springframework.context.annotation.Bean;
+import org.springframework.core.io.Resource;
+import org.springframework.http.CacheControl;
+import org.springframework.stereotype.Component;
+import org.springframework.util.MultiValueMap;
+import org.springframework.web.reactive.function.BodyInserters;
+import org.springframework.web.reactive.function.server.RouterFunction;
+import org.springframework.web.reactive.function.server.RouterFunctions;
+import org.springframework.web.reactive.function.server.ServerRequest;
+import org.springframework.web.reactive.function.server.ServerResponse;
+import org.springframework.web.server.ServerWebInputException;
+import reactor.core.publisher.Mono;
+import run.halo.app.core.attachment.LocalThumbnailService;
+import run.halo.app.core.attachment.ThumbnailService;
+import run.halo.app.core.attachment.ThumbnailSize;
+import run.halo.app.core.extension.endpoint.CustomEndpoint;
+import run.halo.app.extension.GroupVersion;
+
+/**
+ * Thumbnail endpoint for thumbnail resource access.
+ *
+ * @author guqing
+ * @since 2.19.0
+ */
+@Component
+@RequiredArgsConstructor
+public class ThumbnailEndpoint implements CustomEndpoint {
+    private final LocalThumbnailService localThumbnailService;
+    private final WebProperties webProperties;
+    private final ThumbnailService thumbnailService;
+
+    @Override
+    public RouterFunction<ServerResponse> endpoint() {
+        var tag = "ThumbnailV1alpha1Public";
+        return SpringdocRouteBuilder.route()
+            .GET("/thumbnails/-/via-uri", this::getThumbnailByUri, builder -> {
+                builder.operationId("GetThumbnailByUri")
+                    .description("Get thumbnail by URI")
+                    .tag(tag)
+                    .response(responseBuilder()
+                        .implementation(Resource.class));
+                ThumbnailQuery.buildParameters(builder);
+            })
+            .build();
+    }
+
+    private Mono<ServerResponse> getThumbnailByUri(ServerRequest request) {
+        var query = new ThumbnailQuery(request.queryParams());
+        return thumbnailService.generate(query.getUri(), query.getWidth())
+            .defaultIfEmpty(query.getUri())
+            .flatMap(uri -> ServerResponse.permanentRedirect(uri).build());
+    }
+
+    static class ThumbnailQuery {
+        private final MultiValueMap<String, String> params;
+
+        public ThumbnailQuery(MultiValueMap<String, String> params) {
+            this.params = params;
+        }
+
+        @Schema(requiredMode = REQUIRED)
+        public URI getUri() {
+            var uriStr = params.getFirst("uri");
+            if (StringUtils.isBlank(uriStr)) {
+                throw new ServerWebInputException("Required parameter 'uri' is missing");
+            }
+            return URI.create(uriStr);
+        }
+
+        @Schema(requiredMode = REQUIRED)
+        public ThumbnailSize getWidth() {
+            var width = params.getFirst("width");
+            if (StringUtils.isBlank(width)) {
+                throw new ServerWebInputException("Required parameter 'width' is missing");
+            }
+            // Remove the 'w' prefix
+            return ThumbnailSize.fromWidth(removeStart(width, 'w'));
+        }
+
+        public static void buildParameters(Builder builder) {
+            builder.parameter(parameterBuilder()
+                    .in(ParameterIn.QUERY)
+                    .name("uri")
+                    .description("The URI of the image")
+                    .required(true))
+                .parameter(parameterBuilder()
+                    .in(ParameterIn.QUERY)
+                    .name("width")
+                    .description("The width of the thumbnail")
+                    .required(true));
+        }
+    }
+
+    @Bean
+    RouterFunction<ServerResponse> localThumbnailResourceRouter() {
+        return RouterFunctions.route()
+            .GET("/upload/thumbnails/{year}/w{width}/{fileName}", request -> {
+                var width = request.pathVariable("width");
+                var year = request.pathVariable("year");
+                var fileName = request.pathVariable("fileName");
+                var size = ThumbnailSize.fromWidth(width);
+                var thumbnailUri = localThumbnailService.buildThumbnailUri(year, size, fileName);
+                return localThumbnailService.getThumbnail(thumbnailUri)
+                    .flatMap(resource -> getResourceResponse(request, resource))
+                    .switchIfEmpty(Mono.defer(
+                        () -> localThumbnailService.getOriginalImageUri(thumbnailUri)
+                            .flatMap(this::fallback))
+                    );
+            })
+
+            .build();
+    }
+
+    @Override
+    public GroupVersion groupVersion() {
+        return new GroupVersion("api.storage.halo.run", "v1alpha1");
+    }
+
+    private Mono<ServerResponse> getResourceResponse(ServerRequest request, Resource resource) {
+        var resourceProperties = webProperties.getResources();
+        final var useLastModified = resourceProperties.getCache().isUseLastModified();
+        final var cacheControl = getCacheControl(resourceProperties);
+        var bodyBuilder = ServerResponse.ok().cacheControl(cacheControl);
+        try {
+            if (useLastModified) {
+                var lastModified = Instant.ofEpochMilli(resource.lastModified());
+                return request.checkNotModified(lastModified)
+                    .switchIfEmpty(Mono.defer(() -> bodyBuilder.lastModified(lastModified)
+                        .body(BodyInserters.fromResource(resource))
+                    ));
+            }
+            return bodyBuilder.body(BodyInserters.fromResource(resource));
+        } catch (IOException e) {
+            return Mono.error(e);
+        }
+    }
+
+    private Mono<ServerResponse> fallback(URI imageUri) {
+        return ServerResponse.temporaryRedirect(imageUri).build();
+    }
+
+    private static CacheControl getCacheControl(WebProperties.Resources resourceProperties) {
+        var cacheControl = resourceProperties.getCache()
+            .getCachecontrol()
+            .toHttpCacheControl();
+        if (cacheControl == null) {
+            cacheControl = CacheControl.empty();
+        }
+        return cacheControl;
+    }
+}

application/src/main/resources/extensions/role-template-anonymous.yaml

@@ -45,4 +45,7 @@ rules:
     verbs: [ "get", "list" ]
   - apiGroups: [ "api.notification.halo.run" ]
     resources: [ "subscriptions/unsubscribe" ]
+    verbs: [ "get", "list" ]
+  - apiGroups: [ "api.storage.halo.run" ]
+    resources: [ "thumbnails/via-uri" ]
     verbs: [ "get", "list" ]