Support attachment query by media type.

src/main/java/run/halo/app/model/params/AttachmentQuery.java

@@ -15,4 +15,6 @@ public class AttachmentQuery {
      * Keyword.
      */
     private String keyword;
+
+    private String mediaType;
 }

src/main/java/run/halo/app/repository/AttachmentRepository.java

@@ -1,13 +1,23 @@
 package run.halo.app.repository;
 
 import org.springframework.data.jpa.repository.JpaSpecificationExecutor;
+import org.springframework.data.jpa.repository.Query;
 import run.halo.app.model.entity.Attachment;
 import run.halo.app.repository.base.BaseRepository;
 
+import java.util.List;
+
 /**
  * Attachment repository
  *
  * @author johnniang
  */
 public interface AttachmentRepository extends BaseRepository<Attachment, Integer>, JpaSpecificationExecutor<Attachment> {
+
+    /**
+     * Find all attachment media type.
+     * @return list of media type.
+     */
+    @Query(value = "select distinct a.mediaType from Attachment a")
+    List<String> findAllMediaType();
 }

src/main/java/run/halo/app/repository/PostRepository.java

@@ -1,9 +1,8 @@
 package run.halo.app.repository;
 
-import run.halo.app.model.entity.Post;
-import run.halo.app.repository.base.BasePostRepository;
 import org.springframework.data.jpa.repository.JpaSpecificationExecutor;
 import org.springframework.data.jpa.repository.Query;
+import run.halo.app.model.entity.Post;
 import run.halo.app.repository.base.BasePostRepository;
 
 

src/main/java/run/halo/app/service/AttachmentService.java

@@ -10,6 +10,8 @@ import run.halo.app.model.entity.Attachment;
 import run.halo.app.model.params.AttachmentQuery;
 import run.halo.app.service.base.CrudService;
 
+import java.util.List;
+
 
 /**
  * Attachment service.
@@ -54,4 +56,10 @@ public interface AttachmentService extends CrudService<Attachment, Integer> {
      */
     @NonNull
     AttachmentOutputDTO convertToDto(@NonNull Attachment attachment);
+
+    /**
+     * List all media type.
+     * @return list of media type
+     */
+    List<String> listAllMediaType();
 }

src/main/java/run/halo/app/service/impl/AttachmentServiceImpl.java

@@ -69,6 +69,10 @@ public class AttachmentServiceImpl extends AbstractCrudService<Attachment, Integ
         return (Specification<Attachment>) (root, query, criteriaBuilder) -> {
             List<Predicate> predicates = new LinkedList<>();
 
+            if (attachmentQuery.getMediaType() != null) {
+                predicates.add(criteriaBuilder.equal(root.get("mediaType"), attachmentQuery.getMediaType()));
+            }
+
             if (attachmentQuery.getKeyword() != null) {
 
                 String likeCondition = String.format("%%%s%%", StringUtils.strip(attachmentQuery.getKeyword()));
@@ -151,6 +155,11 @@ public class AttachmentServiceImpl extends AbstractCrudService<Attachment, Integ
         return attachmentOutputDTO;
     }
 
+    @Override
+    public List<String> listAllMediaType() {
+        return attachmentRepository.findAllMediaType();
+    }
+
     /**
      * Get attachment type from options.
      *

src/main/java/run/halo/app/web/controller/admin/api/AttachmentController.java

@@ -100,4 +100,10 @@ public class AttachmentController {
 
         return result;
     }
+
+    @GetMapping("mediaTypes")
+    @ApiOperation("List all of media types")
+    public List<String> mediaTypes(){
+        return attachmentService.listAllMediaType();
+    }
 }